We all know that toxic substances have been introduced to the natural environment through pollution and haphazard waste disposal practices, contaminating our air, water resources and soils. Buildings also contribute to the quality of our health and our environment in a number of ways. Many of you have already become familiar with allergy problems associated with indoor air quality, including pollutants, excess moisture and stale air. But few of us think about the connection between the increasing toxicity of these environments and our long- term health.
Toxins
The Industrial Revolution enabled mass production and exponentially increased our ability to produce man-made products, as well as make improvements to existing products. While many of these developments were made possible due to the invention of chemicals, it has not been until recently, with public scrutiny and liability litigation regarding the safety of many of these substances, that there has been much activity on limiting their use. Studies by Environmental Defense Fund and the US Environmental Protection Agency (EPA) have found that the vast majority of chemicals in widespread commercial use do not have basic toxicity data published in public records. Reports indicate that there are 2,863 chemicals (excluding polymers and inorganic chemicals) that the US either produces or imports in quantities of over one million pounds per year. The Toxic Substances Control Act (TSCA), passed into law in 1976, basically grandfathered the existing 62,000 chemicals in use at that time from being banned by the Environmental Protection Agency (EPA). Since that law was enacted, the EPA has only been able to require testing on a few hundred chemicals, yet the total number of chemicals has increased to over 85,000 today. Of the 16,000 chemicals that have been identified as cause for concern, the study concluded that only 7 percent (just 203 chemicals) had publicly available results for all eight of the standard basic screening tests, and over 43 percent had no data in any test category.
The majority of chemicals currently used in manufacturing have never been tested to determine their toxicity to humans or the environment. And under the TSCA, the EPA has mostly failed to exercise what little ability it has to restrict the use of even the most dangerous chemicals. Furthermore, the agency lacks the resources needed to provide any evaluation of chemical combinations and mixtures. The very few tests that have looked at the typical chemical combinations used today have found that the combinations are far more toxic than were their components when tested alone.
Unfortunately we are finding out too late that current research reflects that our past years of exposure to some of these substances may have contributed to the explosion of cancer, Alzheimer’s, autism and other catastrophic illnesses, as well as learning disabilities and infertility. These toxins, commonly referred to as volatile organic compounds (VOCs) are off-gassed by products made with those same uncontrolled or untested chemicals, including many building materials used in construction of our homes, work places and other commercial and public buildings. Breathing these toxins into our lungs can lead to respiratory issues. Many adults now suffer from allergies and chemical sensitivities. And what about our children? They spend much more time indoors since the inventions of computers, cell phones with texting and video games. This directly relates to the fact that the incidence of asthma is 3 times greater than it was just 25 years ago, now affecting 1 in 10 children. Autism now affects one in 88 children, a 20-fold increase in the last 20 years. Numerous research studies indicate that exposure to certain common chemical substances have been linked to these conditions.
Chemical vapors are also absorbed through our skin, making their way into our bloodstream. Ultimately, continued exposure impacts our organs, down to the cell level, compromising our overall health and leading to increased incidence of illness and weakening our immune systems’ ability to fight disease. Unfortunately, often those most affected by these harmful chemicals are innocent third parties. These include indigenous people in remote areas of the world, those most closely tied to the natural environment for their food, water and shelter. Many of these areas have been devastated by mining and unsustainable forestry practices, and many of these people work in these operations with little or no protections from exposure. Additionally, these populations have little, if any, access to healthcare capable of addressing those issues. A vast majority of all manufactured products contain some inherent risks to workers, both in factories where the products are made and those installing the products on jobsites. These workers are more likely to have frequent or continued exposures, often during critical off- gassing curing periods of these chemical compounds. In many instances, these are low-income workers who often do not have healthcare coverage, so this also represents a significant burden on publicly funded healthcare systems.
Some compounds continue to release toxic VOCs for years, though, so we are exposed to low levels but over much longer periods of time, and this exposure can cause just as devastating conditions. It is of great importance that we know how to read the Material Safety Data Sheet (MSDS) for the chemicals that will be used in the construction of our homes. By federal law, every outlet that sells a chemical must be able to provide the MSDS sheet to the public. Ask and ye shall receive. Ask your builder for the MSDS sheets for the paint, glues, adhesives, caulks, varnishes and other products that he and his subs will be using in the construction of your home. You should receive them within a few days. Other building materials pose indirect risks to our health through their contamination of our environment, which is directly related to their life cycle processes. Human health suffers, again, from degradation of our soils, water and air, and also from the entire food chain and the delicate balance of life on our planet being disrupted. Over time, the cumulative damage ultimately threatens some species with extinction through poisoning or habitat destruction.
However, as a result of the recent increased awareness of the effects on our health of exposure to these chemicals in manufactured goods, we are seeing more development of “green chemistry.” Major chemical manufacturers are now supporting a new generation of safer ingredients, recycled content and less damaging processes. Make sure their claims are supported by researching the MSDS disclosures on their products and verifying the ingredients through credible third-party sources.
Sick Buildings Although the term “sick building syndrome” has been around for some time, mostly it has been associated with commercial office buildings, where workers sat in cubicles for eight hours each day in a highly toxic environment. Poor fresh air ventilation was compounded by years of off-gassing of commercial carpets glued down with toxic adhesives, full of accumulated pollutants and chemicals used in attempts to clean or sanitize them. Add to that the use of toxic materials in building products like asbestos (ceiling tiles, flooring and insulation), mold and mildews from past water leaks, off-gassing of toxins from laminated office furniture and commercial upholstery, high levels of electromagnetic energy, noise pollution and numerous other contributing factors, and it is not just the buildings that get sick. The syndrome itself refers to the higher incidence of workplace absenteeism, reduced productivity and higher insurance claims.
But how many of us ever dreamed that we would find similar situations in our homes? The very place that was supposed to be our safe haven may turn out to be the main source of our toxic exposure. The average American spends approximately 90 percent of their time indoors, where air quality can be 2 to 5 times (or sometimes up to 100 times) worse than outdoor air quality. In other words, we have a high exposure to these unseen contaminants. Sometimes odors or smells give us a clue, but our reaction has been to cover these up with air fresheners (more chemicals!) or scented candles (petroleum-based wax toxins plus more chemicals for fragrance!). How many of you reading this still think that that “new car smell” is a good thing?
What Are These Toxins and Where Do We Find Them?
The most important materials that affect indoor air quality are those within the walls of the structure, including interior finish products. Most interior wall construction is air and vapor permeable, so toxins within the walls can seep out, impacting indoor air quality. When insulation, subfloor materials, synthetic gypsum and even glu-lam or other engineered wood beams off-gas toxins from the binders used in their manufacturing processes, these toxins readily enter your living environment.
The National Toxicology Program of the US Department of Health and Human Services publishes a report that identifies substances and exposure circumstances that are “known or reasonably anticipated to cause cancer in humans.” A couple of the chemicals covered in the report are commonly found in building materials. Formaldehyde, specifically urea-formaldehyde, is used in the binders of many common building products, including plywood, particleboard and fiberglass insulation, and styrene (used in the manufacture of some carpets, carpet backings and carpet adhesives). Currently polystyrene-based foams dominate both the spray foam and the rigid foam board insulation markets. Additionally, the flame retardant used on spray foam products also off-gasses toxic VOCs.
These products are a combination of chemicals that must be mixed in proper ratios and applied under appropriate climate conditions by appropriately trained professionals for both performance and safety. Unfortunately, many times the crews doing the mixing and installation have not been properly trained. Sometime the weather doesn’t comply with their hurried work schedules. Chemicals not properly mixed and installed release toxic VOCs at much greater rates.
Even properly installed spray foam has at least a 12-hour curing period. Most of the toxic off-gassing will occur during this period, so it is best to cross the full day after the foam installation off your construction schedule and not allow any other work inside the house during that time. By manufacturer specifications, no one is to be inside the home during spray foam installation unless they have the required protective clothing and dual canister respirators. It’s best to open all the windows and allow the building to air out for the day. It is especially important that drywall not be hung during this period, as drywall is an air barrier and will trap off-gassed VOCs within the wall cavities.
