DD--Volatile Organic Compounds (VOCs)
Volatile Organic Compounds (VOCs)
Organic chemical compounds are everywhere in both indoor and outdoor environments because they have become essential ingredients in many products and materials1.
VOC means any compound of carbon, excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates and ammonium carbonate, which participates in atmospheric photochemical reactions, except those designated by EPA as having negligible photochemical reactivity.
VOCs are organic chemical compounds whose composition makes it possible for them to evaporate under normal indoor atmospheric conditions of temperature and pressure.
Indoors, VOCs are mostly released into the air from the use of products and materials containing VOCs.
The existence, or otherwise, of VOCs, and the total amount measured is not a proxy for the “healthiness” of a product. All VOCs are not “equal” (some are more toxic than others) and all chemicals in a product are not VOCs (and these non VOCs could be more toxic than the VOCs present). Because VOC regulations are based on ozone reduction, toxic chemicals that do not form ozone are excluded from the required VOC calculations, as are toxic metals. The only way to know which toxic chemicals are in a paint product, and therefore how “healthy” it is, is to know the full list of its ingredients.
Potential Health Effects from VOCs.
Health effects may include: eye, nose and throat irritation; headaches, loss of coordination and nausea; damage to liver, kidney and central nervous system. Some organics can cause cancer in animals, some are suspected or known to cause cancer in humans. Key signs or symptoms associated with exposure to VOCs include: conjunctival irritation; nose and throat discomfort; headache; allergic skin reaction; dyspnea; declines in serum cholinesterase levels; nausea; emesis; epistaxis; fatigue; dizziness. The ability of organic chemicals to cause health effects varies greatly from those that are highly toxic, to those with no known health effect. As with other pollutants, the extent and nature of the health effect will depend on many factors including level of exposure and length of time exposed. At present, not much is known about what health effects occur from the levels of organics usually found in homes.
There are several generally referenced measures for VOCs coming from materials.
EPA Method 24.
Currently, the United States Environmental Protection Agency’s (US EPA) Method 24 is used to test the VOC content of coatings. It is widely accepted that Method 24 is not reliable for the analysis of low VOC water-borne coatings. Method 24 is also not suitable for determining the VOC content of solvent-borne coatings containing high levels of exempt compounds. In both cases the reason for the unreliability of Method 24 results from its being an indirect method of measuring VOCs in these types of coatings. A California Air Resources Board (CARB) Method Survey states this clearly: “… the success in reducing the VOC content has created problems with Method 24 itself, due to the indirect way in which it calculates VOC content from other measurements”. In addition, Method 24 cannot determine the level of hazardous air pollutants (HAPs) in coatings.2
ASTM Method D 6886.
“Speciation of the Volatile Organic Compounds (VOCs) in Low VOC Content Waterborne Air-Dry Coatings by Gas Chromatography”, developed at Cal Poly and published as an ASTM standard method in 2003. This method gives a significant improvement in precision to that of Method 24. The method measures the VOC fraction in water-borne coatings directly, since it was determined that very low VOC levels in water-borne coatings were very difficult or impossible to measure by Method 24. According to the ASTM, the improvement in precision using D 6886 instead of Method 24 is approximately tenfold and improves further as the VOC content approaches zero. Negative VOC values are not obtained as is sometimes the case for low VOC coatings using Method 24.3
California Specification 01350.
Standard method for the testing and evaluation of volatile organic chemical emissions from indoor sources using environmental chambers.4 This test is performed on samples which have been allowed to “cure” for a period of fourteen days at which time they are tested for emissions – which are categorized as total VOCs, target VOCs (which are considered more harmful) and aldehydes (including formaldehyde). Performance requirements include a limit for the total VOCs measured, with specific upper thresholds for VOCs which are considered to be of concern. This test measure is better suited to new construction where buildings could remain unoccupied for several weeks following completion, and where VOCs would be able to disperse before the building was inhabited. For renovation projects, where a building will be occupied either during, or shortly after work is completed, emissions measured at fourteen days are less helpful – particularly as many products have peak emissions as they are applied and dry.
EPA Method 8260B.
Method 8260 is used to determine volatile organic compounds in a variety of solid waste matrices.5 This method is applicable to nearly all types of samples, regardless of water content, including polymeric emulsions. The test identifies sixty six specific compounds, including some of the most problematic chemicals commonly found in paints such as: benzene, chlorobenzene, methylene chloride, styrene, tetrachloroethene, toluene, vinyl acetate, vinyl chloride and xylene. In addition to these named compounds, Method 8260 can be used to quantitate most volatile organic compounds that have boiling points below 200oC. Using standard quadrapole instrumentation and the purge-and-trap technique, measurement limits are approximately 5 µg/kg and paint can be analyzed in its wet form.
The Oddy test6 is a procedure created in order to test materials for safety in and around art objects. Materials for construction are evaluated for safety. However, though materials may be safe for building purposes, they may emit trace amounts of chemicals that can harm art objects over time. Acids, formaldehyde, and other fumes can damage and even destroy delicate artifacts if placed too close. A wet paint sample is placed in an airtight container with three coupons of different metals and a small amount of de-ionized water to maintain a high humidity, then heated at 60 degrees Celsius for 28 days. If the metal coupons show no signs of corrosion, then the material is deemed suitable to be placed in and around art objects. The Oddy test is not a contact test, but is for testing off-gassing.
Toxicity Tests and Ingredient Declarations.
ASTM D-42367 is the standard practice of labeling art materials for chronic health hazards. The designation "conforms to ASTM D-4236" means all of the potentially hazardous components of the product have been clearly labeled on the product packaging. Some common components, such as solvents, cause allergic reactions or are dangerous if they touch the skin or the eyes, others can cause respiratory problems if over-inhaled. The ASTM D-4236 standard requires these components to be listed on packaging, and checks specifically for oral toxicity, eye irritation, skin irritation, respiratory tract irritation, sensitization, corrosion, and chronic toxicity.
Declare labels8 are issued to products disclosing ingredient inventory, sourcing and end of life options. In particular, they reference a “Red List” of harmful chemicals which must be declared if present in the material. Declare labels are based on the Manufacturers Guide to Declare, administered by the International Living Future Institute (ILFI) and certified for use in Living building Challenge projects. Accepted for LEED v4.
Health Product Declarations (HPDs).
The HPD Open Standard9 provides a consistent, and transparent format to accurately disclose the material contents, and associated health information of a building product. Accepted for LEED v4.
Juvenile Product Manufacturer’s Association.
The Juvenile Products Manufacturers Association (JPMA) is a non-profit association representing approximately 250 manufacturers who make 95 percent of the prenatal to preschool products in the U.S. market. Each of the JPMA Certification Programs is foundationally built on an ASTM standard with federal and state requirements layered on, as well as many of the major retailer requirements.10
British Allergy Foundation.
The British Allergy Foundation11 evaluates products through testing carried out by independent laboratories to protocols which have been created for the Seal of Approval by leading allergy specialists, specifically to benefit the sufferers of allergy, asthma, sensitivity, and intolerance.
The European Standard EN7112 specifies safety requirements for toys. EN71-3 relates to the total migration of toxic metals (Arsenic, Mercury, Selenium, Barium, Lead, Antimony, Chromium, and Cadmium) in a material to determine if it is safe for use in children’s toys – which could be chewed, or placed in a child’s mouth.