Volatile Organic Compounds: It more than just the smell

The Environmental Protection Agency (EPA) found that the concentration of volatile organic compounds (VOCs) — easily evaporating organic compounds with one or more carbon atoms — was up to 100 times higher indoors than outdoors. According to the EPA, indoor air pollution is one of the top five leading health risks in the United States. Paint, glues, and synthetic fabrics are among the leading contributors of VOCs in the home.

There is also a growing understanding of the health concern called multiple chemical sensitivity, which throws the immune system out of balance. This environmental illness can develop through massive exposure to toxic chemicals through industrial spills or occupational exposure. More often, however, people develop multiple chemical sensitivity through prolonged exposure to lower levels of some chemical or a mix of chemicals.

People who develop multiple chemical sensitivity must restrict their contact with chemicals including those in many paints.

Volatile Organic Compounds

In an attempt to improve air quality, the 1990 Clean Air Act required the EPA to set national limits on air pollutants, including VOCs, that could be released into the air.

VOCs are found in the solvents of all oil-based paints and in some additives in latex paint. The VOCs off-gas as the finish dries. They mix with nitrous oxide — a by-product of fossil fuel combustion — and sunlight to produce ground-level ozone, which is a component of smog. There are toxic chemicals that off-gas in many paints including acetone, formaldehyde precursors, and ammonia, but they don’t count as VOCs because they don’t react to produce smog.

There are two popular misconceptions about VOCs in paint: That they are the “stink factor” in paint and that dry paint no longer off-gases. In reality some VOCs give traditional paint its characteristic odor but many more VOCs have no detectable odor. And it is estimated that more than 50% of the VOCs in paint are still being emitted one year after application.

The terms “low-odor” or “low-VOC” paint can be used to identify the VOC content that meets the EPA standard of 250 grams per liter (g/L) for latex paints or 380g/L for oil-based paints.

This standard is confusing for a number of reasons, including:
• The 250g/L refers to flat latex paint but not higher sheens with higher VOCs.
• The standard applies to untinted paint. Universal tinting machines add VOCs.
• The standard refers to interior paint. Exterior paint would have more VOCs.
• The standard was set to address exterior air pollution, not interior air quality.
• The standard can be used by manufacturers to advertise paint as low-VOC and low-odor when it simply is in compliance with EPA regulations.
• The Green Building Industry has pushed companies to develop paints with much lower VOCs than the EPA regulation.

Green Seal, the non-profit organization that does independent third party certification for environmentally preferable products, sets a more stringent standard of 50g/L for flat interior paint or 150g/L for other paint.

Green Seal’s GS-11 standard for new paint also prohibits a host of EPA-allowed chemicals such as benzene, formaldehyde, and toluene. Green Seal also requires paints to meet stringent performance standards for abrasion resistance and washability.

Interior flat, un-tinted paint with VOCs in the range of 5 g/L or less can be called “Zero-VOC Paint” according to the EPA’s Reference Test Method 24.

While zero-VOC paint is a healthful trend, the toxics still remaining in paint promoted as low-odor or even zero-VOC paint can still make sensitive people sick. Even Green Seal’s GS-11 standard allows ammonia, which is a physical irritant. And many low-VOC paints contain such toxic ingredients as crystalline silica, fungicides, and bactericides.

Natural Paints

Natural paints are not produced from man-made petrochemical-based ingredients. They are specialty paints made from naturally obtained raw ingredients including citrus peel extracts, essential oils, seed and nut oils, tree resins, mineral fillers, tree and bee waxes, and natural — not chemically processed — pigments.

The binder in casein paint consists of milk solids. One product contains only milk products, hydrated lime, and natural earth pigments. The classic binder in natural oil paints was linseed oil, but contemporary versions may use castor oil with citrus or eucalyptus oils to speed drying and improve the aroma.

Water-based natural paints give off almost no odor, but oil-based natural paints are not odor-free, and chemically sensitive people may want to try samples to test for personal tolerance.

Manufacturers of natural paints believe that because their ingredients are not synthesized, they easily assimilate into the natural world without harmful effects.

They also point out that the product-to-waste ratio is greatly reduced by selecting raw natural ingredients that do not need extensive processing. Synthesizing ingredients for ordinary paint from petrochemicals can result in a waste ratio as high as thirty tons of waste to one ton of finished product.

Recycled Paint

Locally, MetroPaint is made up of all the useable latex paint that comes through Metro’s household hazardous waste facilities and community hazardous waste round-ups. Recycled paint inherently has a higher VOC number because it is a consolidation of paint that is already tinted, has a mixture of sheens, and is a blend of vinyl and acrylic resins. Untinted flat acrylic paint would have lower VOCs.

MetroPaint is periodically tested for a variety of potentially harmful compounds, including volatile and semi-volatile organic compounds and heavy metals including lead. Testing shows that levels of these compounds are well below all regulatory requirements, including EPA, Consumer Product Safety Commission, and the Green Seal Standard GS-43 for recycled paint.

In 2006 Metro tested 32 batches of its recycled paint, and the content averaged 149 g/L with no single batch over 200 g/L. This is well below Green Seal’s GS-43 standard of 250g/L for recycled paint.

While this is more VOCs than paint promoted as zero-VOC, the VOCs in recycled paint have already been manufactured, and when it is used instead of virgin paint this reduces the need to manufacture more synthetic VOC-emitting ingredients.

Precautionary Principle

Generations before us lived by the proverb “Better safe than sorry.” Recently this adage has grown into the “precautionary principle.” The 1998 Wingspread Statement on the Precautionary Principle summarizes the rule: “When an activity raises threats of harm to the environment or human health, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically.”

The greatest flaw in most toxics policies is that they are based on the belief that science must provide definitive proof of harm before protective action is taken.

Not knowing the long-term impacts of the combinations of ingredients off-gassing in paint, it is wise to for pregnant women or people with health problems to avoid painting and not go into a freshly painted room until it has ventilated for at least 72 hours.

Others should paint with proper ventilation. Provide cross-ventilation by keeping windows wide open during painting, for two to three days after painting, and longer if possible. Use a box fan secured to the window frame to blow paint fumes outward.

Air-conditioning units and most heating systems do not provide ventilation because they recirculate air even when the system is set to “vent.” They should not be substituted for the use of a window fan blowing outward and fresh cross air ventilation. Likewise, bathroom/kitchen exhaust fans do not always vent outside and should not be used.

While painting, take frequent fresh air breaks and if possible avoid newly painted rooms for several days.

Don’t paint when the temperature is low — for most paints that means below 55º F (surface temperature) — or when the humidity is high — 70% or above — because the paint will take longer to dry. Don’t even paint inside when it is raining because using a box fan during wet weather can be an electrical shock hazard.

Paint fumes rise as paint dries, so it takes the longest time to dissipate paint fumes from the ceiling because there is no fresh air above the fumes once they hit the ceiling. If the room has a ceiling fan turn it on as well as having the windows open to bring in fresh air.

Points to remember:
• Read label precautions.
• Never use exterior paint inside.
• Proper preparation makes paint last longer, and less frequent repainting means fewer VOCs released into the air.
•Dark, deep (highly saturated), or bright colors made from transparent tint bases usually have little titanium dioxide for hiding power. These colors will require multiple coats and that translates into more VOCs released.
• Lighter colors using less universal tint will release fewer VOCs.