By Dr. Mercola
Americans spend 87 percent of their time in enclosed buildings and 6 percent of their time in enclosed vehicles.1 That’s a total of 93 percent of your life spent inside, breathing indoor air.
Levels of many pollutants concentrate indoors, where levels are often 2 to 5 times higher than typical outdoor concentrations.2 A major source of such pollutants is household dust, which is often regarded as more of an aesthetic problem than a health-harming one.
However, once you learn what’s actually lurking in your household dust, you’ll never look at a dust bunny the same way again…
Dust Contains More Than 7,000 Species of Bacteria and Fungi
Your home, like your body, is filled with a vast variety of microbes, many of which live in your household dust. In a study of dust from 1,200 US homes, the dust in each home contained an average of more than 5,000 species of bacteria and 2,000 species of fungi.3
Study co-author Noah Fierer, associate professor in the Department of Ecology and Evolutionary Biology at the University of Colorado at Boulder, said:4
"Every day, we're surrounded by a vast array of organisms in our homes, most of which we can't see… We live in a microbial zoo, and this study was an attempt to catalog that diversity.”
What was perhaps most intriguing about the findings was that the microbial makeup of the dust could be used to predict information about the homes, such as which ones had cats and dogs, and how many females and males lived there.
Houses with only makes had a different microbial makeup than those with only female or a mix of genders, for instance.
There were also trends according to geography, as a great deal of the fungi in household dust is blown in from outdoors via soil and leaves.
The fungi in Midwest household dust therefore tended to be different from that in Southern homes. The findings might prove useful for future allergen research or even for helping forensic investigations.5
Keep in mind that while the vast quantities of bacteria and fungi in household dust may be surprising, this isn’t necessarily what makes it a health risk. While many of the bacterial and fungal microbes may be harmless, the chemicals and other pollutants that tend to collect in house dust decidedly are not.
Can Household Dust Make You Fat?
Researchers recently uncovered that certain materials in house dust can turn on a protein called PPAR-gamma (peroxisome proliferator-activated nuclear receptor gamma).
This protein triggers fat cells to grow and may be involved in obesity. In laboratory tests, PPAR-gamma was turned on after exposure to less than one milligram (mg) of dust, which is concerning because children are thought to ingest about 50 mgs of dust daily.6,7
Initially the researchers suspected that chemicals, such as flame retardants, may be responsible for the potential obesity link, but a more surprising cause was revealed. In a second study, the researchers found fats in the dust, including oleic acid from vegetable oils, could be responsible.
The fats may enter your home’s air and eventually settle into your dust, from regular cooking, or they may be part of hair and skin cells shed by people and pets.8
While more research is needed on this potential connection (you’re already probably exposed to far more oleic acid from the food you eat than you would be from household dust), it poses more avenues by which chemical contaminants in your home could be contributing to weight gain.
One of the studies published in Environmental Science & Technology even revealed that 28 of 30 semi-volatile compounds commonly found in indoor dust were PPAR-gamma antagonists.
This means they could bind to and activate PPAR-gamma, which is involved in regulating fat metabolism, cell proliferation, and cell death.9
“The researchers found signs of significant PPAR-gamma activation in more than half of the 25 dust samples collected from homes, offices, and gyms, at a level of exposure that would be similar to a child’s daily dose.”
What Other Chemicals Are Lurking in Your Household Dust?
There’s good reason to vacuum and/or wet mop your home regularly, and it’s not to pass a “white glove” inspection by a nosy relative… that dust is likely filled with toxic chemicals.
Unfortunately, when your home is filled with goods that contain potentially toxic chemicals, where do you think those chemicals end up when they come out of carpeting, couch cushions, and the like? Many of them end up in your home’s air from which they eventually settle into household dust.
Not only do products inside your home (such as furniture, electronics, plastics, etc.) “shed” chemicals over time, but pollutants may enter your home on your shoes or via open windows. So those dust bunnies accumulating in the corners can be among the most toxic concoctions of all! As noted by the Environmental Working Group (EWG):11
“Ordinary house dust is a complex mixture of generally yucky stuff – pet dander, fungal spores, tiny particles, soil tracked in on your feet, carpet fibers, human hair, and skin, you name it. It's also a place where harmful chemicals are found.
One recent study by the Silent Spring Institute identified 66 endocrine-disrupting compounds in household dust tests, including flame retardants, home-use pesticides, and phthalates.”
Flame Retardants Common in Household Dust
Exposure to contaminated household dust can potentially be dangerous. Take flame retardants for example. The Washington Toxics Coalition tested household dust and also found flame-retardant chemicals in all samples tested.12
Higher exposures to flame retardants called polybrominated diphenyl ethers, or PBDEs, have been linked to decreased fertility, which could be in part because the chemicals may mimic your thyroid hormones.13
Previous research has suggested PBDEs can lead to decreases in TSH (thyroid-stimulating hormone).14 When present with normal T4 levels, low TSH is typically a sign that you're developing hyperthyroidism, which can have significant ramifications both for you and your unborn child if you're pregnant.
One type of PBDE (decaBDE) is classified as a possible human carcinogen by the US Environmental Protection Agency (EPA), while the others remain largely untested.
A study by researchers at the University of California, Berkeley also revealed that both in utero and childhood PBDE exposures were associated with neurodevelopmental delays, including poorer attention, fine motor coordination, and cognition in school-age children15 – and these chemicals are probably lingering in your house dust right now, along with others, like phthalates.
What Are the Additional Health Risks of Exposure to Contaminated Dust?
Phthalates are a group of "gender-bending" chemicals causing males of many species to become more female. These chemicals have disrupted the endocrine systems of wildlife, causing testicular cancer, genital deformations, low sperm counts, and infertility in a number of species, including polar bears, deer, whales, and otters, just to name a few.
One 2002 study by the Environmental Working Group detected phthalates in nearly three-quarters of personal care products tested, which means when you spray one in your bathroom (or use a makeup powder that contains it), the chemicals can become airborne and accumulate in your dust.16 Even low levels of chemicals have the potential to cause health problems, especially in children. EWG explained:17
“When you're exposed to certain toxic chemicals – even at very low doses – your health can be adversely affected. Dust is simply another way for the toxic chemicals in your house to reach your body. Young children are of special concern because their developing bodies are more vulnerable to toxic exposures, and they ingest or inhale more dust than adults since they – and their toys – spend lots of time on or very near the floor.
They also put dusty hands and toys in their mouths often. Scientists once thought children got lead poisoning by literally chewing on windowsills. We've since learned that it's actually caused by their normal play behaviors because contaminants like lead stick around in house dust.
In the case of fire retardants, which are commonly found in household dust, scientists have found that exposure to minute doses of toxic PBDEs at critical points in a child's development can damage reproductive systems and cause deficits in motor skills, learning, memory, and hearing, as well as changes in behavior.”
Creating Less Toxic House Dust Starts with You
One of the best ways to reduce your exposure to toxic dust is to make your household dust less toxic to begin with. This involves bringing fewer toxic household goods into your home, from the food you eat to your shower curtain. Top tips include:
- As much as possible, buy and eat organic produce and free-range, organic meats to reduce your exposure to added hormones, pesticides, and fertilizers. Also avoid milk and other dairy products that contain the genetically engineered recombinant bovine growth hormone (rBGH or rBST).
- Rather than eating conventional or farm-raised fish, which are often heavily contaminated with PCBs and mercury, supplement with a high-quality purified krill oil, eat smaller fish, or fish that is wild-caught and lab tested for purity. Wild caught Alaskan salmon is about the only fish I eat for these reasons.
- Buy products that come in glass bottles or jars rather than plastic or canned, since chemicals can leach out of plastics and into the contents.
- Store your food and beverages in glass rather than plastic, and avoid using plastic wrap.
- Use glass baby bottles and avoid plastic sippy cups for your little ones.
- Eat mostly raw, fresh foods. Processed, prepackaged foods (of all kinds) are a common source of chemicals such as BPA and phthalates.
- Replace your non-stick pots and pans with ceramic or glass cookware.
- Filter your tap water — both for drinking and bathing. If you can only afford to do one, filtering your bathing water may be more important, as your skin absorbs contaminants. To remove the endocrine-disrupting herbicide Atrazine, make sure the filter is certified to remove it. According to the Environmental Working Group (EWG), perchlorate can be filtered out using a reverse osmosis filter.
- Look for products that are made by companies that are earth-friendly, animal-friendly, green, non-toxic, and/or 100% organic. This applies to everything from food and personal care products to building materials, carpeting, paint, baby items, upholstery, and more.
- Use a vacuum cleaner with a HEPA filter to remove house dust, which is often contaminated with traces of chemicals.
- When buying new products such as furniture, mattresses, or carpet padding, ask what type of fire retardant it contains. Be mindful of and/or avoid items containing PBDEs, antimony, formaldehyde, boric acid, and other brominated chemicals. As you replace these toxic items around your home, select those that contain naturally less flammable materials, such as leather, wool, and cotton.
- Avoid stain- and water-resistant clothing, furniture, and carpets to avoid perfluorinated chemicals (PFCs).
- Minimize your use of plastic baby and child toys, opting for those made of natural wood or fabric instead.
- Only use natural cleaning products in your home or make your own. Avoid products that contain 2-butoxyethanol (EGBE) and methoxydiglycol (DEGME) — two toxic glycol ethers that can damage fertility and cause fetal harm.18
- Switch over to organic brands of toiletries such as shampoo, toothpaste, antiperspirants, and cosmetics. You can replace many different products with coconut oil and baking soda, for example. EWG has a great database19 to help you find personal care products that are free of phthalates and other potentially dangerous chemicals. I also offer one of the highest quality organic skin care lines, shampoo and conditioner, and body butter that are completely natural and safe.
- Replace feminine hygiene products like tampons and sanitary pads with safer alternatives.
- Avoid artificial air fresheners, dryer sheets, fabric softeners, or other synthetic fragrances.
- Look for products that are fragrance-free. One artificial fragrance can contain hundreds –even thousands – of potentially toxic chemicals.
- Replace your vinyl shower curtain with one made of fabric.
How to Dust Like a Pro (and Keep Toxins to a Minimum)
House dust may be toxic, but the good news is that it’s very simple to remove from your home. As mentioned, you’ll want to vacuum frequently with a HEPA vacuum, which will be more efficient at trapping small particles and removing contaminants from your home than regular vacuums. There are other strategies as well, however, including these straightforward tips from EWG:20
Wet mop your hard floors regularly, which will prevent dust from accumulating. Wipe furniture with a wet or microfiber cloth. The small fibers of a microfiber cloth cause the dust to cling to it, while a wet cloth will attract and hold dust better than a dry one. Avoid chemical dusting sprays, which will only add to your home’s chemical load. Caulk and seal cracks and crevices where dust might otherwise accumulate. Use high-quality filters in your forced-air heating or cooling system and change them frequently. Damp dust your electronics frequently; these are a common source of flame-retardant chemicals in your dust. Pay special attention to dusting areas where young children crawl, sit, and play.