All Posts by Jennifer Faul

Actinobacteria: Another danger lurking in Water Damaged Buildings

Avoiding mold and mycotoxins has taken a major share of the spotlight in healthy home discussions, and for good reason, because they can elicit major allergic responses in many people and disabling immune responses in very sensitive people.  However, there is another organism that grows right along with mold in moist environments, and it’s often overlooked even though it can produce the same types of reactions.  Some types of bacteria are unique enough to be in a class of their own, called actinobacteria.  

Here’s a short refresher from an article about bacteria, endotoxins and exotoxins:  bacteria can be classed into two different groups: “Gram-negative” or “Gram-positive”.  These classes are based on a test developed by scientist Christian Gram in 1884, which differentiates the bacteria using a purple stain.   According to webmd.com, bacteria either have a hard, outer shell, or a thick, mesh-like membrane called peptidoglycan.  The hard outer shell will resist the purple stain, and show up as a red color.  These are called “gram negative” because the purple stain did not show.  Bacteria with the peptidoglycan absorb the purple stain much more easily and are called “gram positive”.  The stain also tells many more characteristics about the bacteria and the way it interacts with treatment. 

Going back to actinobacteria (also called actinomycetes), they are a diverse group of gram-positive bacteria, meaning they have that mesh-like membrane called peptidoglycan. However, they resemble molds (fungi) because they are adapted to life on solid surfaces and they can produce mycelium (branching structures) and dry spores like most fungi. Actinomycete spores are known to be important air contaminants in occupational environments, such as agriculture and waste composting facilities, and have recently gained special attention as indicators of mold problems in buildings. They do not belong to the normal microbial flora in indoor air but have been found in buildings suffering from moisture and mold problems. (Characteristics of Airborne Actinomycete Spores)  One class of actinobacteria, called mycobacteria, include the types of bacteria responsible for tuberculosis and leprosy.   These actinobacteria require iron for growth, and in the human body, will destroy red blood cells in order to acquire the iron it needs.

Actinobacteria, which occur in both terrestrial and aquatic habitats, are among the most common groups of gram-positive microorganisms in nature.  Living in soil, actinobacteria decompose organic matter and display antagonism against other bacteria and fungi, with which they compete for nutrients. Actinobacteria have incredible abilities to survive under extreme conditions in their natural environment and have been found in strongly saline soils, soils with a high content of exchangeable sodium and/or magnesium ions, and heavy clay soil which is submerged by water.  (Discovery of Actinomycetes from Extreme Environments with Potential to Produce Novel Antibiotics).  If they can live in these extreme environments, it’s not too much of a stretch to find them indoors in water-damaged buildings (WDB) and indeed, they thrive there too.  In a 2017 study of an office building in the northeast US which had a history of water incursions via roofs, walls, and pipes, actinobacteria were detected in 74% of dust samples, and thermophilic actinomycetes (unique high-temperature aerobic bacteria) were most predominant (81%) among the three types.   In analysis of building occupants who participated (105 participants out of 136 occupants), the increasing thermophilic actinomycetes levels in floor dust were significantly associated with decreased pulmonary function and increased odds of having symptoms reflecting possible granulomatous disease, particularly shortness of breath on exertion, flu-like achiness, and fever and chills.  Prevalences of the three granulomatous disease-like symptoms among the occupants were similar to those reported in another study of a large office building with eight hypersensitivity pneumonitis and six sarcoidosis cases, a long history of moisture incursions, and high fungal and bacterial contamination.   

Dr. Ritchie Shoemaker, an expert on mold illness and CIRS, published the paper Exposure to Actinobacteria resident in water-damaged buildings and resultant immune injury in Chronic Inflammatory Response Syndrome in 2021.  In it, he details some of the interesting facts about actinobacteria that many people do not know:

• Geosmin is a VOC that accounts for the characteristic musty smell found in many WDB, and many actinobacteria also produce this VOC, creating the logical fallacy that the smell found in WDB buildings is only due to mold growth.  
• Certain species of actinobacteria live on humans: on our skin and in mucous membranes and genitourinary tracts.  He denoted these HH actinobacteria (for human habitat), as opposed to SH actinobacteria (for soil habitat).   The interior of WDB are usually colonized by HH actinobacteria much more than SH actinobacteria; this is not the same for fungi, because WDB are easily colonized by outdoor (SH) fungi.  (Airborne Bacterial Communities in Residences: Similarities and Differences with Fungi)  
• Dr. Shoemaker developed indices for exposure to actinobacteria showing differences in subsequent immunoreactivity in Chronic Immune Response Syndrome (CIRS) patients for actinobacteria from human skin carriage, HH, as opposed to SH actinobacteria.  
• He theorized that the “toxin” that causes the immunoreactivity is not exotoxins, like normal gram-positive bacteria, but extracellular vesicles of 20-150 nanometer size that carry potentially inflammatory molecular signaling compounds from inside the cell wall to the outside. Vesicles are known to contain a variety of charges including nucleic acids, lipoproteins, enzymes, and toxins.  

“Better Health Guy” Scott Forsgren, Functional Diagnostic Nutrition Practitioner interviewed Dr. Larry Schwartz, an indoor air expert with a specialty area is assessing, testing, and creating solutions to make homes and workplaces environmentally safe for patients with inflammatory illnesses, about actinobacteria.  According to Dr. Schwartz, one can get treated for symptoms of CIRS (of which there are 37), but not necessarily get to the root cause.  However, if their blood is tested by GENIE (Genomic expression: Inflammation Explained), root causes for CIRS can be discovered.  “We found over 2,000 patients that have taken the GENIE test. About 42% of them are being triggered by Actinomycetes. The next largest percentage was endotoxins. The least percentage was the mycotoxin.”   (podcast: Episode #171: Actinomycetes with Larry Schwartz, BSME, MBA, CIEC)  Some background on GENIE:  this test was developed by Dr. Shoemaker and Dr. James Ryan, a molecular biologist, who have collaborated on genetic testing since 2011. GENIE is a gene expression assay composed of 188 genes that is performed on a single blood specimen. It reveals gene expression abnormalities found most often in patients facing CIRS illnesses. Typically it's done repeatedly, once before treatment for CIRS, after the first eleven steps of the treatment protocol, during or after VIP treatment. (vasoactive intestinal polypeptide). VIP is a naturally occurring human neuropeptide which affects multiple pathways in the brain and throughout the body, and it’s given as a low-dose nasal spray to benefit patients with severe CIRS.  GENIE results will show if the patient's metabolism is improving as their treatment progresses.

Dr. Schwartz’ research exposed that the major “factory” of actinobacteria (he calls them “actinos” for short) is the bedroom, because of the time we spend under covers (warm temperature) and the amount of skin cells that are deposited in the bed.  He also characterizes showers, crawlspaces and basements and drains as places where actinobacteria tend to multiply because of constant moisture.  He has a bedding protocol for cleaning bedsheets, and drain “protocol” on how to clean drains on a regular basis so that actinobacteria will not continue to proliferate in them.  (check out minute 59:17 of the podcast for these protocols).  Dr. Schwartz also advocates for use of HEPA filters, PCO devices (like the Air Angel Mobile) and bipolar devices (like the Mold Guard).  We would also add that the use of bathroom exhaust fans and humidity control are paramount for lowering relative humidity.  

Dr. Schwartz acknowledged that similar to the way pathogenic mold makes mycotoxins,  many pathogenic species of actinos often create a chemical called mycolic acid, which may be the allergy trigger for CIRS patients.  Dr. Ritchie Shoemaker also found that mycolic acids played a role in inducing T-cell responses (Exposure to Actinobacteria resident in water-damaged buildings and resultant immune injury in Chronic Inflammatory Response Syndrome)  According to the physicians with which Dr. Schwartz consults, although actinos can trigger inflammation and CIRS, they are not necessarily triggering histamines, and mast cell activation, because mast cell activation is primarily a histamine-driven effect. 

As for testing, EnviroBiomics is the only lab known by Dr. Schwartz that does next generation sequencing (NGS) to determine levels of actinos in home samples. Using special lab equipment called NGS processors, they give the in-depth degree of data on the speciation of actinos and their concentrations.  Dr. Schwartz can analyze the results of these test reports, in conjunction with at-home or virtual visits, to determine what may be exacerbating CIRS symptoms.  In one case, a client who lived in a farmhouse on 3 acres had CIRS, but the cause was not in his home.  It turned out that a neighboring property had a dilapidated barn with rotting hay in it (“farmer’s lung” disease comes from the actinobacteria in rotting hay), and correction of the ventilation in his home significantly improved his symptoms.  

Now for the good: despite its ability to cause illness, scientists and researchers have discovered how to harness actinomycetes for healing purposes.  Antibiotics are a class of molecules used for the treatment and prevention of bacterial infections.  These bioactive compounds are produced naturally from different species of fungi and bacteria, but the most attractive class of microorganisms that are able to produce these secondary metabolites are actinobacteria, in particular, actinomycetes. The importance of this order is due to their abilities to produce different classes of antibiotics in terms of chemical structure and mechanisms of action. Moreover, different genera and species of actinomycetes are able to produce the same class of antibiotics and, in few cases, the same chemical compound.  Thanks to antibiotics and the research developed in this field, many infections are now treatable, and life-quality/life expectancy are better than in the past.  (Actinomycetes: A Never-Ending Source of Bioactive Compounds—An Overview on Antibiotics Production)  

In short, actinobacteria can be confused with mold because of many similarities: how they grow, the environmental conditions they prefer, what they smell like, and what symptoms they cause in humans.  The good thing is that regular cleaning of areas like the bedroom, bathroom and drains to remove dust and allergens also removes food for actinobacteria.  In addition, a whole-home approach also examines the ways that toxins from actinobacteria inside walls and even outside can enter the home via leaks and negative air pressure.  When cleaning protocols are introduced and these air pathways are addressed, actinobacteria numbers start to dwindle and the homeowner’s health increases.  Sometimes it takes a trained eye to discover where they are flourishing, but by knowing their preferred habitat and via testing, they are not completely “in the dark” anymore! 

Would you rent or subscribe for

clean air?

Ok, I’ve heard of all kinds of rentals and subscription plans. But, air is public domain, right?  How on earth does such a subscription get delivered?  Certain companies have air purifier machines that can be rented by the day or week, etc., which can be really helpful if you only need the equipment for a short time. 

Vacations:  Personally, I think the vacation rental option here is brilliant–how many times have you gone on vacation or to a conference, and the hotel room seems musty (of course, this happens in a hotel that is fully booked with no way to change rooms)?  Here are some options for renting air purifiers to trap the contaminants in the air while you work or play:

• Rents4baby.com:  This company rents a premium air purifier for only $15 a day in the Orange County area, with the option to upgrade to a medical grade filter for only $5 per day more.  They have many more baby products, as well as more pickup and delivery locations in the US.  They can deliver to airports and car rental places, making it easy to pick up an air purifier and have a great vacation with or without little ones!
• Lyft has teamed up with Wynd, an air purifier company, to add an air purifier option to rental cars.  At only $15 per day, you can add a Wynd purifier to your rental to get out those odors and unseen germs that cleaning did not remove.   If you plan on doing a lot of driving on your next trip, it’s worth checking out!

For parties and indoor events: 

• Sunbelt Rentals Portable Air Scrubbers:  This company has a large selection of units for many different uses–light commercial or residential units, medical grade, odor removal–you name it!  They had a super-fast response when I emailed for more rental info.  Their S-, M-, and L-Light purifiers feature H13 true HEPA and carbon filters.  The filters for these machines cost extra, but in general, the rental prices are very reasonable ($17-53 per day in the Orange County area). 

For remediation jobs (like moving into a house that had noxious pet or smoke odors, or remediating mold damaged areas):

• Home Depot Dri-Eaz HEPA Air Scrubber:  Near our Orange County, California location, there are several stores that have this machine, which will purify a 1000 square foot space with up to 500 cubic feet per minute air flow.  The carbon and HEPA filters are included for $159 per day or $318 per week.  (After this point, you would be better off buying one!)
• The same scrubber from Home Depot rents for less in Petaluma and San Rafael, CA from CalWest Rentals ($70 per day or $250 per week).

If you don’t live in California, try searching for “air purifiers for rent near me”.  Admittedly, renting purifiers is more expensive than buying them in the long run.  But if you have a trip, project, an event, or some other short-term need for clean air, you have options!

Do you need a really large quantity of clean air?  Enter pulsed electromagnetic field radiation, which has actually been around for a while.  It’s similar to wi-fi or the systems used by cellphone services.  It is broadcasted in short pulses and has been used since the early 1990’s in wastewater treatment applications.  The pulses of RF energy contact small particles in the air (it actually works best on particles less than 20 nm) and increases their negative charge, to accelerate the particles grouping together and falling out of the air.  These small particles will settle as dust, which if inside a building can be vacuumed, or if outside will be absorbed into the earth’s natural soil.

Devic-Earth is a company based in India that has designed a Clean Air Subscription, which utilizes their unique equipment under the name of “Pure Skies”.  Companies such as heavy industry, cities, or event halls can subscribe continuously or for only a month, depending on their needs. The process claims to  improve air quality by 33-90% over large areas at the lowest cost per unit area.   The equipment is usually installed in a matter of hours and can cover spaces inside with a minimum of 20,000 ft2 or outside with a minimum of 5 acres.  What’s most interesting is the way this technology can overcome many types of air pollution for organizations that had no control over pollution previously.  For example, one testimonial stated that the equipment was employed that Delhi (India) half-marathon in 2018, and another 25K (Tata Steel Kolkata) to achieve results of 30-54% improvements.  The results are measured from before the equipment is turned on, and monitored throughout deployment, by an air quality monitor.  The studies and testimonials also report the presence of rain, which can also drastically reduce air pollution because it causes particles to fall to the ground with the rain. 

This particular provider assures the safety of its equipment/process because it uses “ISM frequency band similar to the Wi-Fi spectrum (2.4-2.5 GHz) and power levels are maintained under standard regulations.”   The dangers of Wi-Fi are not generally agreed upon, with many governments and organizations taking the stance that Wi-Fi is safe, such as Canada.  Many studies are like this one, however: they have found that non-thermal EMF exposures have major impacts “on both of the most important intercellular regulatory systems in the body, the nervous system and the endocrine systems…major impacts on what may be the most important intracellular regulatory system, the calcium regulatory system… we also have non-thermal EMFs attacking the DNA of our cells, putting our biological inheritance at great risk. As living organisms, EMFs attack each of the most important functions that go to the heart of our human complexities.”  

I did note that on Devic-Earth’s website, the company claims that “Pulsed radio waves are periodic bursts of radio waves or radio frequency energy (RF). The pattern of these bursts depends on the desired effect.  This is unlike the radio wave transmission from telecommunications equipment such as Wi-Fi or mobile towers which are usually continuous in nature.” 

Wi-Fi by nature is a pulsed system.  The previously referenced study notes that “pulsed EMFs are usually much more biologically active than are non-pulsed (also known as continuous wave) EMFs of identical frequency and similar average intensity (study references from years 1965-2015). This pattern of action is particularly important because all wireless communication devices, including Wi-Fi (2015 studies) communicate via pulsations and are likely to be particularly dangerous as consequence of this. (One 2015 study) have argued that the more pulsed they are, the more damaging EMFs will be and while this may still be questioned, it may well be a roughly applicable generalization. It is also true that artificial EMFs are polarized and this makes artificial EMFs particularly dangerous (2005 and 2015 studies). Polarized EMFs put much larger forces of electrically charged chemical groups than do non-polarized EMFs (2015 study)”.  Because of their statement of being different from Wi-Fi, Devic-Earth’s Pure Skies may be at a slower pulse in comparison to Wi-Fi.  It’s not known if this pulse is less or more detrimental than Wi-Fi to cells and our nervous and endocrine system and DNA.  Most people are unaware of this potential damage and as such, don’t have a problem working and living in Wi-Fi zones (it’s a welcomed convenience), so that Pure Skies technology would probably also be acceptable and welcomed by most people.  It may not even need to be disclosed in many places.

Whether by filter, EMF or other technology, now I know you can rent clean air for your room, house, car, convention center or even an outdoor event!

Testing out TotalClean: a breath of fresh air for anyone who cleans

TotalClean is our new powerhouse non-toxic cleaner and I’m very impressed!  Since it’s non-toxic to humans and pets and safe for most surfaces, there are unlimited uses for it in the home.  

Here's some helpful facts about it:

• You can use the pre-mixed 32 oz. spray bottle, or mix your own with the concentrate.  When mixing your own, I found it was useful to have several empty spray bottles available in plastic or glass (your preference) to make various strengths and keep them available (for instance, keep a spray bottle and some paper towels in the bathroom for deodorizing and cleaning whenever needed!) 
• TotalClean has no smell, yet it deodorizes the air and surfaces by eliminating odorous bacteria on contact.  
• TotalClean does not lose its effectiveness over time, unlike cleaners such as hydrogen peroxide and hypochlorous acid.
• TotalClean is safe to mix with other natural and non-toxic ingredients such as vinegar, baking soda or hydrogen peroxide to boost its efficacy.  For instance, I have a white synthetic cloth shower curtain that gets pink mildew around the hem after several months.  It's not super-easy to take down, so I used to soak the hem in a small container of bleach water to brighten it.  I had to leave the exhaust fan for over 4 hours until it dried!  This time, I used normal strength TotalClean mixed with 1/2 cup hydrogen peroxide, and the pink disappeared as if I had used bleach, with no smell or toxic fumes!  Here are the before and after photos:

• The industrial formulation for TotalClean is used in many wastewater treatment plants around the country, so we know it's safe for city wastewater and home septic systems.

Check out our video on getting started with the concentrate and keep reading to learn about its many uses!

Normal strength: that which comes pre-mixed in the 32oz. spray bottle (1:7 parts TotalClean to water)

• Windows and mirrors: For nice streak-free cleaning, spray the surface with TotalClean and use newspaper to wipe dry.  If mixing TotalClean from concentrate, using distilled water or zerowater leaves less residue/streaks because no minerals from the water remain on the glass.
• Counters: Spray non-greasy stone, tile, and wood countertops with TotalClean and wipe dry with a paper towel or clean cloth.  For greasy countertops, see concentrate solutions below.
• Bathroom sinks: Cleans off toothpaste spatters and dust easily
• Cabinets (except greasy cabinets: see concentrate below): spray and wipe with a clean cloth
• Dishwasher: White vinegar is highly acidic and although it cleans, it can damage gaskets and seals if used straight from the bottle. You can use TotalClean safely (even in concentrate form!) on all exterior and interior parts of a dishwasher including: door gaskets, filters, spray arms, drain, and anywhere visible food/waste buildup shows.
• Refrigerator: You can wipe down the exterior, interior and door seals with TotalClean, with no need to rinse unless you have a lot of food particles.  I loved the fact that I could clean shelf by shelf as I had the time, without the hassle of unloading the whole fridge for fear of contamination (as with toxic cleaners containing bleach).  Spray TotalClean on hard or sticky spills, wait a few minutes for it to soften, and wipe away.  Here is an example of before spraying and after spraying (not even wiping):

• Floors: Use this normal strength ratio (1 part TotalClean to 7 parts hot or warm water) to get tile and ceramic floors really clean!  If you have sealed wood floors, TotalClean is also a safe substitute for any water-based cleaner (just make sure to wring out your mop well and not flood the floor). 
• Laundry deodorizing: spray-soak extra-stinky clothing items with TotalClean before washing.  See note at end of post regarding optical brightening. 
• Shoes: Spray material and allow to soak for 30 min before washing in water and dish detergent and rinsing thoroughly, to kill odors
• Washing Machine cleaner: spray the seals and wipe on front-loading machines to keep them free of mold and mildew, and spray and wipe exterior surfaces to remove dust and laundry detergent
• Dusting: Make your dustcloth damp with TotalClean and wipe away dust
• Deodorizing: spray TotalClean into the air in and around kitchen garbage, pet litter trays, bathrooms, laundry rooms, into shoes, and anywhere odors linger
• Carpet cleaning: mist TotalClean lightly onto carpets, allow to dry, and vacuum. For deep cleaning, use this solution in a carpet cleaning machine and be sure to vacuum thoroughly to remove moisture. 
• Cleaning mold from tile grout: Since grout is porous, if possible start with dry grout so that it will absorb TotalClean deep into the grout.  Spray-soak the area and wait 5 minutes, then scrub with an old toothbrush or stiff brush and flush with water.  If this does not remove stains, go to the concentrate (see below)
• Car interiors: Dampen a cloth with TotalClean and wipe over dashboards, gauges and any solid surface, as well as vinyl or leather seats.   To freshen/clean upholstery and carpets, spray onto surface and use a wet-dry vacuum to remove moisture, or use TotalClean in an upholstery cleaning machine instead of toxic commercial cleaners (see our post on How to Clean your car’s interior to keep away mold)
• Cleaning mildew from exterior siding: Spray on mildew, wipe with a soft brush or rag, and spray with water to rinse clean. Here are some before and after photos of painted wood siding using minimal effort (I used a carwash brush, and in the 2nd photo you can see some of the untouched surface on the left side):

Uses for Concentrate:

Double (1:3 parts TotalClean to water):

• For deep carpet cleaning, use TotalClean at 1:3 or 1:1 ratio of cleaner to water in a carpet cleaning machine and be sure to vacuum thoroughly to remove moisture.  If using a wet-dry vacuum, spray the carpet with this solution using a spray bottle, agitate with a stiff brush (if it does not damage carpet) and vacuum out with the wet-dry vac.

Two to One: (2:1 parts TotalClean to water)

• Degreasing countertops: Grease spatters will wipe clean quickly with this solution.

Full-strength concentrate: 

• Cleaning greasy kitchen cabinets: The cabinets above cookstoves can get very tacky with residue from cooking oil vapors.  I found that full-strength concentrate will take off the tackiness and restore the smooth finish on the cabinets above my stove.  Use it in a spray bottle and wipe with clean towel or paper towel.
• Cleaning deeply stained mold areas from tile grout: Since grout is porous, if possible start with dry grout so that it will absorb TotalClean deep into the grout.  Soak the area and wait 10 minutes, then scrub with an old toothbrush or stiff brush and flush with water.  

What else do you think it can do?  If you have a specific question or comment about using TotalClean, contact us!

Power Outages and Air Quality

It’s not hard to imagine nowadays: hot weather, cold weather, storms, electrical grid system hacking, or just plain equipment failure are all reasons you could lose power to your house.  In that case, there are a number of things to consider and ways you can prepare. 

Generators:  If you are going to keep a generator as a backup power source, have a plan on where you will run it.  It’s NOT OK to run a gas-powered generator in an attached garage, or even next to an attached garage.   According to the U.S. Centers for Disease Control and Prevention, CO poisoning sends more than 20,000 Americans to the emergency room and kills upwards of 400 during a typical year. (USNews.com) Gas-powered generators need to be placed at least 20 feet from the house, so that exhaust fumes can dissipate. To plan for this, make sure you can roll the generator to a safe operating place (preferably a fenced yard) and have a dedicated extension cord of the proper gauge wire to run to your home.  Inside your home, you should have a working CO monitor on each floor so that you can be alerted should the CO level rise. Change the batteries in the CO monitors once a year when you change smoke alarm batteries.  CO doesn’t even need open doors or windows to enter your home, so don’t circumvent these guidelines!  Other safety tips for generator operation: (redcross.org)

• Keep fuel in approved safety cans
• Be sure to shut off the generator and let it cool down before refueling
• Don’t operate it in wet conditions; you can install a tarp or other temporary cover over it to keep it and the ground it’s standing on, dry.

Window screens:  Of course, ventilation sans electricity requires planning too.  It’s hard to keep the windows open for ventilation without proper-fitting screens.  If you don’t normally open the windows, now is the time to plan for having to do so. 

1. Get windows working (here’s a video on how to unstick painted windows using a variety of tools and techniques). 
2. If your windows are missing screens, plan to order at least one screen per side of the house, per floor.   You’ll want to allow cross-ventilation, so this means if you have a traditional four-sided, two-story house, you’ll need at least eight screens if you keep the interior doors open for cross-ventilation.  For bedrooms with multiple windows, it’s helpful to have an additional screen (2 total) in the bedroom so that you can get cross ventilation in the bedroom, even with the door closed.  Here’s a page that will help you order the right size screens and the right hardware.  Or, order adjustable window screens that will fit many different size windows.   
3. For existing screens, consider having them re-screened in new material like AllergyGuard or PollenTec.  These screen materials are actually fine filters that block way more pollen, dust, and particles than traditional screens.  AllergyGuard boasts that it blocks particles from 0.3 to 10 microns, more than 69% of UV Light and 50% of Infrared Light, and over 95% of water and rain spray (allergyguard brochure). 

Cookstoves:  Electrical outages don’t necessarily mean eating cold canned food if you have a gas grill.  The grill could be standard or mini size ($89 at Amazon); the key is having the proper fuel ahead of time.  This mini grill is designed to run on small propane tanks (about 5 lb cylinders), but with a connective hose you can connect it to a larger cylinder.  As with any unvented gas appliance, it has to be placed outside!  Open carports with a cross-breeze are an ideal place to grill and stay protected from the weather.  Another option is to go old-school and have a small charcoal grill and bag of charcoal on hand.  Charcoal grilling takes a little practice; the key is building a hot bed of coals before starting to cook.  In order to eliminate the use of lighter fluid (the fumes of which go right into your food and cause photochemical smog), use a chimney starter like this one to get the coals nice and hot for a great grilled meal.  Alternatives to using a chimney starter are placing a charcoal briquet in each compartment of a cardboard egg carton, closing it and lighting each end of the carton, or placing wadded up newspaper below a pile of charcoal briquets, and lighting the newspaper.  These methods allow the cardboard or newspaper to burn slowly and allow time for the charcoal to catch fire.

Avoiding mold:  Without air conditioning and dehumidification, it's only a matter of time before mildew and mold will start to grow.  

• Ventilation is the first key to prevention in this case.  If possible, open windows on opposite sides of the home to get cross-ventilation going.  
• Use safe cleaning products that kill mold and odors: 
  • TotalClean uses iodine to safely kill mold and bacteria.  It even eliminates odors when sprayed in the air near trashcans and pet litter.
  • Concrobium Mold Control Spray uses a non-toxic trio of salts to kill mold and prevent future mold from growing.   You can spray it on draperies (test on a small area first), wood, and other furnishings to prevent mold when you’re not able to prevent high humidity. 

Staying cool:  Sleep is essential but it’s no fun trying to sleep when it’s hot.  Fans provide evaporative cooling (moving air that causes moisture to evaporate from your skin, taking heat with it).  Here are some innovative products to get cool and get some z’s:

• Portable battery fan: This model from Treva is lightweight and runs an amazing 65 hours (source: camping review) on one set of 6 D-cell batteries.   It also has an AC adapter for use when the power is on.
• Got an old-fashioned hot water bottle?  Fill it with one layer of ice cubes to chill down your bedding and keep you cool.  Or, strap small ice packs to your body’s pulse points (wrists, ankles, back of knees, armpits) using sports bandages or long socks.
• Sleep out in the open.  Before modern air conditioning existed, the concept of a “sleeping porch” was used in the summer.  If it’s very hot, you can try sleeping on a covered porch with some protection from bugs.  You’ll need: 
  • A portable bed, cot or hammock so the bed is elevated off the floor for more ventilation
  • A mosquito net to protect from biting bugs:  there are many to choose from!  Try a single net for one person, or an outdoor screen house for several people

It’s an unpredictable world, so a little preparation will help you not to “sweat” the inconvenience of losing power.  Let us know what innovations you come up with to stay safe and cool during summer outages. 

Air-Sealing your Home

Wow, the revelation that Ultrafine Particles (UFPs) from outdoor pollution can easily penetrate a home’s interior through cracks and leaks has really stirred our thinking.  Specifically, a 2018 study on UFPs from airport traffic during prevailing winds caused indoor pollutants to rise by 1.7 fold (170%), and HEPA filtration inside the homes only lowered them by 33%.  What does this mean?  Our homes are leaky, and no amount of indoor air filtration can keep up when outdoor pollutants are raging!  This could be wildfires, oil refineries, a major highway, a major port, or any heavy industry or power plant.  Basically, the only way to keep outdoor pollutants outside is to either seal the building envelope better, or use a positive pressure system where the inside of the building stays pressurized, so that airflow is always inside to outside.  

Before we get into the specifics, home builders in the past usually only concerned themselves with one barrier, a vapor barrier.  This was the felt paper, housewrap or other system installed under the cladding that prevented rain and moisture from entering the building.  A vapor barrier is not the same as an air barrier, and air barriers are much less common in residential and even commercial construction.  We’re talking about air barriers in this post, as air barriers are one way to block UFPs from entering your home.  

Here are some options for making an air barrier (sealing the building envelope):

From the outside: this is best accomplished during construction or major renovation:

• Applying a membrane air barrier like Delta Vent SA over sheathing involves primer, tape and the barrier; this video shows how it is installed and the tape is preferred to caulking in preventing air leaks.

• Spray Wrap MVP from Prosoco can be used as the primary air barrier over above-grade wall assemblies prepared with joint and seam filler.

From the inside: there are 3 ways to seal the inside: Before drywall, using the drywall itself as an air barrier, and after drywall. 

• Before drywall: 

• Use a product like Knauf Insulation EcoSeal, a waterbased elastomeric sealant.  First the exterior sheathing is installed and taped.  Then the sealant is applied to all interior seams and cracks with an airless sprayer at 1700 to 2200 psi, which really forces the sealant into any cracks. It fills gaps from 1/16” to ⅜”.  Here is a description of how it’s installed. 

• OwensCorning EnergyComplete is a two part insulation and air-sealing system.  First a latex sealant is sprayed on the interior of sheathing (like Knauf Insulation Ecoseal), then the wall cavities are filled with either blown-in insulation (by using netting to retain the insulation) or with spray foam. 

• You can apply an air barrier like Intello Plus (ceiling video, wall video, penetrations video) on the underside of ceiling joists, all along walls, sealing it to the subfloor.  Again, run a blower door test before installing drywall so that large leaks can be corrected. 

• Use spray foam: spray foam is seen as a one stop shop that insulates AND seals, but it requires careful installation and checking through a blower-door test.  This article shows how an older house that is renovated with sprayfoam insulation can be surprisingly leaky.  The application of the foam is incredibly important in creating the seal, as small gaps between the spray foam and the back of the drywall can make a highway between penetrations.  The air barrier needs to be tested before the drywall is installed so that foam imperfections can be corrected.

• Use AeroBarrier: This is a waterborne acrylic sealant that is sprayed into a pressurized space, using the pressure to guide the sealant into any cracks or crevices.  The process can be applied pre- or post-drywall with any type of insulation.

• Using drywall: if you skip an air barrier membrane, you can use the drywall itself to make an air barrier.  The most problematic areas are the joints and penetrations, which can be addressed using the right materials.  You’ll need special electrical boxes, gasket material, expanding foam, flexible caulk and adhesive; here are 2 articles on what to consider and how to hang airtight drywall. 

• After drywall: it’s not ideal, but you can still make major sealing improvements after your home is “finished”.   Start by doing a visual check for daylight or artificial lights around the door and window perimeters when they are closed.  You can use your hand or a candle to find air leaks and drafts as well.  Check under sinks and behind appliances like refrigerators and gas stoves for wall penetrations that have not been sealed.  Once you’ve sealed as much as you can with foam (be careful using expanding foam), caulk, and weatherstripping, call in an energy auditor to do a “blower door test” to see what you may be missing.  They should be able to tell you how leaky the home is in terms of “Air Changes per Hour” (ACH), and suggest and/or perform other remedies to lower the ACH, making the home tighter.

Because of the continued increase in interest for air-sealing homes and businesses, there is an Air Barrier Association of America (abaa.org).  The association is “committed to educating the public about air barrier systems and developing a professional air barrier specialty trade and industry dedicated to the installation of effective air barrier systems in buildings on a nationwide scale.”  Here are some of the resources they have:

• Here are some of the systems they’ve tested for air barriers.

• You can search for a specialist in your area here. 

• Courses for installers, auditors, and whole building airtightness technicians (with applicable fees but open for anyone to take)

Air-sealing your ducts for better air quality and energy savings 

In our post “How does indoor air pressure affect ventilation and air quality?” we show a photo of a room being aerosol sealed from the inside out.  This is a great way of closing up the small leaks (up to ½” diameter) that are overlooked by design flaws or construction crews, in order to seal the home’s thermal barrier before finish work on the home is completed.  Here’s how this innovation started: duct sealing.

Before rooms were sealed from the inside out by aerosol sealant, the process was developed for air ducts in 1993.  In one case study by AeroSeal, the innovator and major supplier for this technology, a homeowner had her ductwork expanded to cover previously unserved areas of her home.  After the new ductwork was installed, the system was pressure-tested and it was discovered that air of about 919 CFM (cubic feet per minute) was leaking through the ducts, which is the equivalent volume of about 551 refrigerators per hour(!).  According to energystar.gov, “about 20 to 30 percent of the air that moves through the duct system is lost due to leaks, holes, and poorly connected ducts.”  (To put this in perspective, the average system is 3.5 tons.  A system is required to have 400 cfm per ton of air across the evaporator coil for cooling, thereby 1400 cfm is the normal flow of the average system.  Twenty percent (280 cfm) to thirty percent (420 cfm) would normally leak from the ducts, so this homeowner either had a much larger home, or exceptionally leaky ducts.  In any case, after sealing the ductwork, a 91% reduction in leakage was realized.  Consequently her sinus issues were relieved and she felt more comfort in the home.  The system was previously drawing in dust and contaminants from outside the home and recirculating them in the HVAC system; apparently this problem was relieved by sealing the ducts.

The following diagram shows how air leaks into and out of ductwork (aeroseal.com):

The home is in heating mode shown by the orange ductwork coming out of the furnace in the bottom right.  Ductwork farther from the furnace turns blue (cooler) because pressurized, heated air is leaking from the ducts into the crawlspace and void spaces, before it even gets to to the farthest room.  For air quality purposes, the most important part of the system is the return areas, in the ductwork in the attic of this house.  Because the air pressure inside return ducts is negative (it is being “sucked” or drawn back to the furnace by the fan), any leaks in this area will cause dusty, unconditioned air from the attic or voids into the ductwork (see green arrows entering the ductwork in the top of the picture).  This is one major cause of excessive dust and poor air quality in many homes.  Even more leaky are the ducts in many multi family homes and apartment buildings.  AeroSeal has been successfully used in these buildings since 2007-8.  

The sealant used by AeroSeal is a “water-soluble organic compound” (AeroSeal FAQs) with an extremely low concentration of VOCs.  The sealant smells like Elmer’s glue when wet, but dries to be odorless. The safety data sheet reveals it to be a “vinyl acetate copolymer” (35% max weight) and “vinyl acetate monomer” (<0.01% when dried).  In accordance with California Prop 65, the product “does not contain any chemicals known to the State of California to cause cancer, birth, defects, or other reproductive harm.”  According to the EPA, vinyl acetate definitely has exposure limits due to irritation of upper respiratory tract as a result of acute or chronic exposure.  Due to this information, it’s possible that very sensitive individuals could have a reaction with the dried substance in their ducts, so it may be wise to ask for samples before it’s applied in the home of sensitive individuals. 

Aeroseal is not the only duct-sealing product on the market.  Here are some other options:

• Aluminum duct tape is available online and at most home improvement stores and can be used by anyone.  

• Ductwork mastic should be applied over the aluminum duct tape. It gives extra strength to the seal and encloses any seams of the tape.  It’s applied by paint brush and is usually water soluble (soap and water cleanup).

• Spray Mastic products: These are typically products for professionals because of the spray equipment needed to apply them. 

• Spray-Seal by Carlisle is a sealant applied to the exterior of ducts (especially hard ductwork) manually either after fabrication or as an upgrade to existing ductwork. 

• PROseal Spray by Ductmate Industries Inc. is a sprayable mastic sealer which is also applied by professional spray equipment.  

• Duct-EZ is a water-based zero-VOC mastic that is not only used to seal ductwork; it is also used to seal cracks in your foundation or basement to reduce seepage of radon into your home.  

Since dust is a major contributor to indoor air pollution, the dust may indeed be coming from the attics and crawlspace, and/or directly from the outside through building envelope cracks and crevices.  Before contracting for a duct-sealing service, it would be wise to have an energy audit on your home performed in order to discover the most economical ways to seal the largest leaks.  

These steps convert your HVAC into a whole house filter

Many people have central air conditioning/heating, yet they don’t know that this machine could be used year round to improve the air quality in their homes.  For such an expensive investment, it’s wise to get the most out of it–everyday!  Here are a number of tips to do just that.

1. Air-seal the return ductwork.  We’ve written extensively on air-sealing your home, attached garage and attic, but the return ductwork is super-important too.  A lot of contractors use wood or drywall to “frame” a duct but without sealing the corners, you are pulling dusty air from wall cavities, the attic and maybe even under your house, if the return air grille is near the floor.  Here is a great video on what to do and which products to use.  Air-sealing your ductwork is not a bad idea, either.

2. Make air filter changes top priority!

If you’ve finally gotten on a schedule of changing your HVAC filter, we applaud you!  You are protecting this expensive equipment by preventing an overly-dirty filter from damaging the fan or other components, because dirty filters increase the pressure drop, like trying to suck a Big Gulp through a coffee stirrer.  Try to use a higher MERV filter (like 11, 12 or 13), first by reading our article How can I get more filtration with my current HVAC system, then increasing the MERV if you have enough filter surface area.

3. Seal the filter in place.

There are several ways to make sure that air is not bypassing the filter.  

• This video shows how to seal a vent grille to the drywall using spray foam.  Although this can also be done from the attic (with less chance of dripping messy foam in your house, not all vents can be accessed from above.  

• For the return grille: caulk the filter grille to the drywall.  

• Use filter-sealing tape over the filter:  

• AllergyZone FilterLock Filter Slot Seal, $10, has a magnetic closure to stick securely to your filter slot opening, sealing gaps to maximize filter use.  The video on this page for the product shows how easy it is to install.

• Or, if you have a filter that lies flat in a filter grille, use masking tape or painter's tape to seal the edges of it to the filter grille like in this video (I prefer painter's tape because it removes more cleanly). 

4. If you have a BP-2400 Whole Home Ionizer, install it between the return air filter and evaporator coil, or before the fan, in order to get those ions circulating through your whole home.  Once a year, it helps to de-energize the ionizer and clean of any dust from the brush heads, which will maximize its efficiency.

5. Set the fan to “on”, not auto.  This ensures that the fan is always running even if the heat or AC is not on.  If you’re concerned about the cost of running the fan all year, you don’t have to be.  Check out our article on how to calculate this cost to see that it’s not a lot (~$10 per month or less), especially for the reward of cleaner home air.  The bonus is that circulating air with this fan redistributes air throughout your home, reducing moisture content in soft furnishings and mold growth.

You are ready to go!  Dust, cleaning and personal products, pets, cooking–they all contribute to less-than-stellar indoor air quality, so it’s wise to make the most of what you already have to improve it!

What are ultrafine particles and where do they come from? 

In our post “Which particles can get captured by a filter or by my lungs?”, we mentioned ultrafine particles, which are classified to be 0.1 micron or less in diameter.  They are called UFPs (ultrafine particles) or PM0.1 (Particulate matter 0.1 microns), and are dangerous to our bodies in a different way than PM2.5 (Particulate matter 2.5 microns) , because they can migrate from the lungs or respiratory pathways to the rest of our bodies.  Their movements and concentrations are also different.  Learning about them is a good defense for avoiding them, though, so here’s some of what we know.

• PM2.5 consists of a mixture of particles of varying sizes from a variety of sources, with the most numerous particles by count usually falling within the ultrafine size range (<100 nm).  
• UFPs are mainly composed of organic compounds, elemental carbon, trace metal oxides, sulfates, and nitrate ions (2012 and 2016 studies). 
• Among the sources of emission, heavy industries are considered one of the largest anthropogenic sources of trace metals (2012, 2014 and 2017 studies)
• UFPs are unstable.  They have positive, negative and neutral charges,  and become larger particles through coagulation (when two or more particles combine) and condensation (when additional vapors can condense on the particles) (Jan 2022 overview). 

UFPs can be emitted by a number of sources.  

Source: overview study of UFPs

Since Natural Sources are largely not controllable, let’s focus on the anthropogenic sources (originating from human activity). 

Vehicular, aerial and sea traffic:

Airports: it’s estimated that in the United States ∼40 million people live near 89 major airports (i.e., within areas with ≥45 dB noise levels near airports) (study).

Aircraft exhaust is the #1 pollutant at major airports, and neighborhoods surrounding the airports even 10 miles away have higher ultrafine pollution levels.  According to a 2014 study, the “level of pollution at LAX (Los Angeles International Airport) was equivalent to the emissions generated by nearly 500 vehicles stalled in freeway traffic every day.”  Another study in 2018 in the Boston area measured particle numbers (PN) indoors and outdoors.  PN overall indoors was compared during times of impact-sector winds (during prevailing NW or SW winds) to calmer conditions; during impact-sector winds, the indoor measurements were about 1.7 times that of calm conditions.  We know that particles infiltrate homes via cracks in the building envelope, open windows, or forced-air ventilation, and this was shown through the study because outdoors and indoor PN levels usually increased and decreased in tandem, except for indoor events like cooking or cleaning.  Unlike road emissions, aviation emissions do not dissipate with higher windspeeds because of the buoyant nature of the aviation emissions.  This is the reason that some ultrafine particles, like wildfire smoke, can be transported in upper-atmosphere winds for thousands of miles.  Interestingly, significantly higher UFP emission per kg fuel burned resulted under landing conditions as compared to takeoff conditions. (2021 study)

HEPA filtration inside the homes helped somewhat; it lowered indoor PN by approximately 33%.  This is good, however, it didn’t have the same effect as lower number of flights or no impact-sector winds.  This causes us at HypoAir to continue recommending sealing homes to the best of our ability, and using controlled fresh-air ventilation for homes (via filters).  Ultrafine particles from airports are not currently regulated by the EPA, so we need to protect against them!

Vehicle exhaust: In many urban areas, vehicle exhaust is a major health concern. The following pictorial representation is found in the study “Chemical Composition of Quasi-ultrafine Particles and their Sources in Elderly Residences of São Paulo Megacity”

In urban areas with both aircraft and ground vehicle pollution, vehicle exhaust can be identified by larger particle size and higher BC concentration. (2021 study). 

Likewise, roadway emissions can be characterized by the fuel type, lubricants used, thermodynamic conditions, ignition technology, and the number of vehicles running.  This is why large cities have performed emission inventories in order to reduce particulates in certain ranges by certain types of vehicles.  National and local governments have devised three categories of strategies to control PM emissions: (1) fuel-based strategies, which include reducing sulfur levels; (2) engine-based strategies, which could alter combustion to reduce emissions; and (3) exhaust emission control strategies, which include the use of modern technologies, such as DOCs, diesel particulate filters (DPFs), and SCR catalysts, focusing on reducing emissions after combustion has taken place but before they leave the tailpipe. (2020 article).  New engines, paradoxically, emit more UFPs than older engines (1996 Health Effects Institute), but with these exhaust emission control strategies, UFPs can be captured before they are released.

Marine traffic: According to noaa.gov, 76% of all trade in the US involves some sort of marine transportation, and marine transportation touches 90% of all trade internationally.  Barges are extremely efficient transporters; what other mode can transport a ton of cargo 647 miles on 1 gallon of fuel?  In comparison, trains move 1 ton at 477 miles per gallon, and trucks at 145 miles per gallon. (2017 article).  However, the sheer number of tons of cargo moved on ships and barges necessitates huge quantities of fuel and emissions.  The International Maritime Organization (IMO) mandated lower sulfur contents in marine fuels beginning in 2020, at max 0.5% sulfur down from 3.5% previously for heavy fuel oil (HFO).  This cap caused many ships to start using intermediate fuel oil (IFO) or other lighter fuels instead of HFO.  The sulfur cap is a step in the right direction for less sulfur in the environment, but it was not expected to reduce UFPs (in terms of Particle Number or PN) from shipping sources.  The total output of PN from marine shipping in 2016 was similar to the total anthropogenic emissions in continental areas.   Thus, marine traffic is a significant source of UFPs (2021 Environmental Science & Technology article).

A third major source of outdoor anthropogenic UFPs is from coal-fired power plants, which produce emissions that are particularly rich in metals. You can access a map of US power plants here (gas, oil and coal), that gives type of fuels, emissions, and demographic information of the surrounding area.   Many plants may filter their emissions to meet standards, however UFPs can form outside of the stack when SVOCs condense (gasses turn into solids and thus bypass the filter). (2020 article) This process is called nucleation.  The most persistent UFP sources in the low atmosphere near the surface are modern technology fossil fuel-burning power stations, refineries, and smelters, according to a 2018 study. 

A fourth major source of outdoor UFPs is from wildfire smoke and controlled burns, which can vary significantly depending on the type of wood burned and its moisture content.  Wildfires can also smolder for a long time after being “extinguished”, and this smoke contributes significantly to the total wildfire emissions. 

Indoor UFPs are a combination of what has leaked into the house from the outdoors, and what is generated indoors.  Cooking and cleaning are large contributors, as well as candles, incense, smoking and e-cigarettes, and (in unconditioned climates) mosquito coils.  The use of e-cigarettes by children and young adults is unfortunate because their lungs are more susceptible to damage from UFPs.  Also, if you have a laser printer, it is surprisingly one of the major contributors to UFPs in offices (and homes!).  

Toxicological effects from exposure to UFPs; Jan 2022 overview

Here is what happens when our bodies encounter UFPs.  They are normally inhaled (effects via mucous membranes, skin and eyes are much smaller). The larger particles (10 microns and larger) can be trapped and removed via the mucous system, but smaller particles (2.5 microns and smaller) may be trapped in the alveoli and terminal bronchioles.   UFPs go into the deepest parts of the lung, and the body’s cellular defense system is activated.  This includes macrophages, various cytokines, chemotoxins and leukocytes, including neutrophils. Some of these are involved in the body’s inflammatory response, which not only damages the invading substance, but is also detrimental to the body in chronic doses.  

The UFPs can translocate to other organs such as the brain, liver, kidneys, and because they are fat-soluable, also deposit in adipose tissue. The body’s production of oxidizing species places oxidative stress on the body, which can cause damages to the DNA and mRNA, and lead to cancer.  Even transgenerational changes to DNA can (occur through inheritance!  

The toxicity of UFPs depends on a number of factors, including:  

• The age and health of the person affected (children are most affected, followed by the elderly and pregnant women). 
• The emission source, which determines the makeup, characteristics, size and concentration of the pollutants.  For example, black carbon (BC) is one combustion pollutant made up of PM2.5 and UFPs, but it is more harmful than other PM2.5 because of the body’s inflammatory response to it.  Black carbon can also adsorb other toxins before it is inhaled, like VOCs and PAHs (polycyclic aromatic hydrocarbons).  One study found that the smaller the particle size, the greater the inflammatory effects in the lungs, and the greater the DNA damage.  Another study found a positive correlation between the concentration of UFPs from motorcycle exhaust and the physical of damage to mice kidneys (neurological effects, memory loss,  behavioral problems and changes in brain tissues are other effects). 

With all the sources inside and outside, it seems that UFPs are unavoidable in daily life!  They are everywhere, but here are our top tips for keeping them out of your home and your body:

1. Seal up your home as tightly as possible, and use controlled fresh air ventilation through a MERV 13 filter* (see chart below) and your home’s HVAC system.  Balanced ventilation (as opposed to negative pressure ventilation) has less chance of suctioning combustion exhaust from gas appliances such as gas dryers, water heaters and furnaces.  
2. In addition, use a HEPA filter in your home to capture UFPs that are generated in the home or slip past the ventilation filter. 
3. Bipolar Ionizers like those in HypoAir’s Germ Defender, Air Angel or Whole-Home Polar Ionizer help to cluster ultrafine particles into larger particles that can fall out of the air or be captured in a HEPA filter.
4. Use stovetop ventilation during and after cooking and bathroom ventilation during and after showering.
5. Don’t smoke or vape (use e-cigarettes).
6. Use a HEPA mask (outdoors or in a separate ventilated building if possible) during high-risk activities like welding, spray painting, sanding or woodburning and 3D printers. 
7. Don’t allow vehicles or gas engines like generators or lawn mowers to idle in the garage.  
8. If you move, reconsider locations with high UFPs such as downwind of airports, refineries, power plants, bus stations, major highways, etc. 

*Here is the reason we recommend MERV 13 for ventilation filters:  it increases capture of small particles to include that of smog, tobacco smoke, and cooking fumes. 

Above diagram from pureairfiltersdirect.com

Which particles can get captured by a filter or by my lungs?

This is an incredibly important and somewhat complicated question.  I want to present the following graphic, which shows relative particle size.  I’d say it’s pretty surprising how large our hair is and how small those bacteria, smoke particles and viruses are, right?  The “µm” stands for micrometers, which is one-millionth of a meter.  Micrometers are also called “microns”, so the human hair is 50-180 microns.

In our FAQ on “What is HEPA?”, we explored how filters actually trap contaminants like these.  In order to start answering our original question, let’s review that!

“Sieving” is the most simple way a filter “strains” out the particles that are larger than the openings between the fibers of the filter.  

                  (image from classicfilters.com)

Then, there are three types of motion that particles experience in a stream of air, such as the airstream being drawn through a filter.  Filter design actually takes advantage of the size of particles and the way they move through the air, in order to capture them.  

• Obviously, some particles are larger than others.  Inertia acts on larger particles by causing them to continue in their original path of motion when entering the filter, thus colliding directly into fibers instead of sweeping around them with the accompanying airflow.  Particles 0.3 micron and larger (coronavirus size and larger) are affected by inertia. 

                (image from classicfilters.com)

• Air is made up of all kinds of molecules and particles, which are getting thrown about in erratic ways by collision with one another.  This is called Brownian motion.  Taking Brownian motion into consideration is filtering by diffusion, which occurs when smaller particles travel in an erratic fashion through the airflow and are impeded by fibers.  The particles trapped by diffusion are typically smaller than 0.1 micron.

                         (image from classicfilters.com)

• In direct interception, a particle follows the airstream but travels closer than its radius to the fiber, “brushing” it and becoming stuck.  This can happen for many different sizes of particles and just depends on where they are in the airstream relative to the fibers.  

                    (image from classicfilters.com)

So there you have it– four ways a filter uses to capture particles.  Interestingly, because of the gap between inertia and diffusion, particles around 0.3 microns in diameter are the most difficult to filter out of the air, because they are least affected by these methods.   This is called the most penetrating particle size (MPPS)--the size that is most likely to slip through the filter.  

HEPA filters are rated on their ability to remove this size particle—0.3 microns.   They do so with greater than 99.95% efficiency.   There are 2 ratings of HEPA: H13, which removes at least 99.95% of 0.3 micron particles, and H14, which removes at least 99.995% of 0.3 micron particles.  

Without a HEPA filter in your home, you are probably relying on furnace filters of various lower filtration ratings.  That means that more particles are getting through the filter, and remaining in the air for you to breathe.  Yikes!  Particles of 10 microns or less can be inhaled, and particles of 2.5 microns or less are more likely to deposit deep in the lungs.  (California Air Resource Board).  This size of particle is extremely lightweight, and once it’s in your lungs, it can move all the into the deepest part of your lungs and lodge there.  Without filters to capture particles from the air, unfortunately your airway and lungs will act as filters.  Here is how (Canadian Center for Health and Occupational Safety):

• The respiratory system can be divided into upper and lower regions.  The upper region starts at the nose and mouth, and goes down to the vocal cords in the larynx. The lower region starts at the larynx and extends through the trachea all the way to the bronchioles and aveoli (smallest air sacs).

• Particles 10 microns and larger are most likely to lodge in the upper respiratory region by inertia (also called impaction), because in this region, air is flowing at a higher velocities and during the twists and turns particles tend to continue in their original direction and “impact” a wall of the airway and stick there.

• Interception is likely to occur with fibers, like asbestos fibers.  In the range of 1 micron in diameter and 200 microns in length, if one end brushes an airway wall, it will lodge there.  These can make it into the bronchial tree.

• Sedimentation occurs when particles larger than 0.5 microns loose their momentum and gravity takes over, causing the particles to settle in the bronchi and bronchioles.  

• For particles smaller than 0.5 microns, diffusion is in effect (Brownian motion).  This can happen in the small airways and alveoli, when air has virtually slowed to stillness.  

• Although the mucous lining of our respiratory tracts was designed to clear airways by moving it up and out of the respiratory system, it does not always function well in older and diseased people, and the sheer number of ultrafine particles can clog airways. 

Fine particles (2.5 microns down to 0.1 micron) and ultrafine particles (0.1 micron and smaller) are shown to cause inflammation and inflammatory diseases.  Ultrafine particles can migrate from the alveoli to the bloodstream and to other organs, resulting in delayed sicknesses such as reactions to vehicular pollution, welding fumes and burning trash.  The danger of ultrafine particles is not just their size and number (much greater numbers PM2.5), it is also their charge, which can adsorb toxic chemicals onto their surface.    Fine particles have been shown to cause cardiovascular disease; they travel up the olfactory nerves to the brain; they are inhaled by electronic cigarettes, and have been shown to increase risk for hypertension and diabetes and cause cancer (animal studies) . (study)

For all these reasons, a HEPA filter is a great addition to your home, vacuum, and even a mask when you are performing high-risk activities like welding, spraying paint, or caring for a sick relative, so that the filter will do the work instead of your lungs and body!

Increasing our bodies’ resistance to mold--naturally

There's no "silver bullet", but regarding exposure to mold, there’s a lot we can control, like humidity, water leaks that can be stopped and remediated, air purifiers, etc. Sometimes, though, there are things we just can’t control, like having a new work assignment in a moldy area, or having a scrape (literally) that infects us with mold.   That’s what happened to a young man traveling in Costa Rica, who developed a lesion in his brain due to a type of black mold after scraping his arm on a bike ride.  In India, doctors are facing an unprecedented spike in mucormycosis, an infection from another type of mold species that is very prevalent in the hot, humid country.  Indiscriminate use of steroids to stop inflammation from the virus that caused COVID-19 causes some patients to have weakened immune systems, making them susceptible to infestation of Mucorales, the group of fungi that includes molds responsible for mucormycosis. (Science News)  With Mucorales, the fungi tend to thrive in diabetics because of elevated blood sugar levels, which turn the blood more acidic, creating an ideal environment for it to spread.  Unfortunately, the virus that causes COVID-19 also damages the beta cell of the pancreas, decreasing insulin production needed to check high blood sugar.   

It doesn’t need to be far from home, as this can happen in your backyard.  Candida auris has been identified as a new global threat; it’s a type of fungus that is resistant to 2 out of 3 classes of antifungal drugs.  

Here is what we’re seeing cause susceptibility to fungi:

• Steroid medications, including artificial corticosteroids, which dampen immune function by lowering the number of lymphocytes 
• Stress releases natural corticosteroid in our bodies (decreasing immune function as above) and stress also alters a number of bodily functions like digestion activity, blood pressure, blood cholesterol levels, all of which lead to an increased risk of disease (simplypsychology.org)
• High blood sugar from diet, disease or inadequate medication management
• Other causes of more acidic blood: respiratory acidosis is the body’s response to having too much carbon dioxide in the blood (a common cause would be sleep apnea), metabolic acidosis which includes ketoacidosis, lactic acidosis, renal tubular acidosis and hyperchloremic acidosis (webMD)
• Pre-existing conditions such as AIDS: “According to the Centers for Disease Control and Prevention (CDC), fungi are among the leading causes of opportunistic infections affecting patients with HIV/AIDS [16].” (study)

The good news is that fungi have weaknesses we can exploit.  Here are some of them:

1. Copper: fungus has a small window of tolerable copper levels.  “the human immune system utilizes both copper toxicity and copper starvation in responding to fungal infections. “(Valeria Culotta, PhD) Drinking water stored in copper vessels may provide the excess copper needed to kill many pathogens (healthline.com)
2. Iodine: A lack of iodine has been shown to cause many different diseases and symptoms, including endemic goiter, hypothyroidism, cretinism, decreased fertility rate, increased infant mortality, and mental retardation (article). On the other hand, iodine has been shown to cure toenail fungus (study), and iodine is is rapidly effective against viruses, bacteria (both Gram negative and Gram positive), fungi and spores(oralhealthgroup.com). However, not all iodine preparations have high- germicidal properties.  Molecular iodine (I2) is the form that kills fungus and molds most quickly. Here are the positives about a new formulation of iodine, ioRinse: 

• Does not stain, unlike previous formulations of povidone-iodine
• does not induce resistance development in targeted microorganisms
• substantivity (ongoing residual effect) of iodine for up to 72 hours is well documented.
• Safe for chronic use as a mouthwash
• Affordable
• Molecular iodine is also available in a Nasal Spray (ioMist) to protect sinus passages.

3. Zinc is a metal that is needed for a healthy body and immune system, but it can be stolen by pathogenic fungi such as mold.  Our bodies attempt to withhold this essential vitamin from pathogens (a process called nutritional immunity), but certain pathogens have evolved highly sophisticated methods of acquiring it from hosts anyway. (study)  A 2017 US study carried out over six weeks found that taking just 4mg extra of zinc a day made a major difference to the health of cells, which in turn makes your body better able to fight infections and diseases. The team concluded that zinc reduces ‘oxidative stress and damage to DNA’ that helps protect against chronic diseases.

4. Glutathione: When our bodies are exposed to harmful fungus, they increase production of Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS).  ROS/RNS are helpful in that they signal an invasion of the body and trigger more immune responses, but they also can damage lipids, proteins and DNA (study), and overwhelm the natural antioxidant capacity of our cells, causing the imbalance that is known as oxidative stress. Normally ROS levels are kept in balance with antioxidants in our cells, which is known as cell redox homeostasis, but in the presence of pathogens, ROS increases dramatically, causing inflammation and other potentially damaging symptoms.  Glutathione (GSH), made of the three amino acids cysteine, glutamate, and glycine, is an important antioxidant in our bodies (webmd.com)  Our glutathione levels decrease naturally as we get older, but more acutely during diseases such as cancer, HIV, or Parkinson’s disease.  In a Korean study, it was shown that glutathione significantly increased a cell’s chances of surviving exposure to large amounts of ROS like hydrogen peroxide (H2O2).  Low levels of glutathione peroxidase are also coincident with conditions like vitiligo, multiple sclerosis, and Type 2 diabetes. (drcgolding.co.za).  Therefore, supplementing with this “superhero” antioxidant can significantly improve our outcome when faced with mycotoxins.  Here are some ways to supplement:

• Intravenous (IV) glutathione is the quickest and most effective form of supplementation, but its availability to the public is limited.  
• Although many companies offer glutathione in oral form, it’s generally not effective in raising free glutathione in the blood because digestive enzymes break it down into its three components.  Therefore,  two alternative forms of glutathione that translate to higher glutathione levels in the blood:
  • liposome-encapsulated glutathione, or
  • s-acetyl glutathione: this has been shown to have similar results to IV glutathione (clinicaleducation.org).  
• Whey protein contains free fatty acids that actually inhibit growth of C. albicans (study). C. albicans is the most prevalent form of fungal infections in people (medicalnewstoday.com), and knowing this, supplementation with a whey protein from grass-fed cows can be a good way to increase resistance to certain fungi (moldsafeinspections.com).  

5. Iron: Iron is essential for both humans to grow.  Iron is needed to produce red blood cells and hormones, as well as maintain our immune system response, particularly a level of lymphocytes (scientific article). Here is the conundrum however: fungus also needs iron, and will steal iron from our bodies or scavenge excess iron if it is supplemented.  In healthy people, iron supplements are a good way to make sure we have the iron we need.  (If normal iron supplements upset your stomach, try a “slow-release” formula). However, if you are diabetic, undergoing chemotherapy, or have any other major illness, you may want to consult your doctor before adding an iron supplement, to make sure that it does not feed an invasive pathogen like mucorales, which is particularly disfiguring and deadly in immune-compromised patients. 
6. Healthy gut:  According to ucdavis.edu, “A healthy gut contains healthy bacteria and immune cells that ward off infectious agents like bacteria, viruses and fungi.” In addition, a healthy gut microbiome trains immune cells for guarding the brain:  scientists have discovered that certain plasma cells from the intestines migrate to the brain, where they stand guard to release IgA antibodies to block the entry of pathogens to the brain. (Science News)  How to maintain a healthy gut?  This article discusses some excellent ways to maintain a healthy gut microbiome. 
7. Getting adequate sleep: During sleep, our bodies produce cytokines and T-cells, both of which are important to our immune response.  We’ve discussed how to get the most of your sleep time in a previous post, and this article from uchealth.com reviews the ways you can promote quality sleep.  

We’ve got the power to reduce the chance of acquiring nasty and life-threatening fungal infections, even in this world of ever-increasing dangerous microbes.  I hope this article gave you some new insights on some weapons in our immunity arsenal.