The message is loud and clear: human activity and human invention are affecting negatively the planet and the general health of the world's population. This does not mean that significant improvements and advances in health and well-being have not occurred as a result of human activity and invention. But our tacit acceptance of these advances and conveniences left us vulnerable to the negative effects, now realized at a global scale as climate change and at a micro-scale as carcinogenic material, e.g., included in the manufacture of cellular phones.
The good news is that awareness of these problems is rising across the planet, and many significant changes are being made. In healthcare, for example, Boulder Community Foothills Hospital was the first facility to achieve a silver LEED certification in December 2003. A visit to the facility is refreshing. From groundhogs playing at the edge of sidewalks to operable windows in the patient rooms, this medical center for women and children welcomes staff, visitors, families and patients with stunning views of Boulder, day-lit interiors, gardens, local and, thus, familiar materials such as brick and sandstone, intimate seating areas, and a blend of interior finishes and furnishings that are low- to no-VOC and formaldehyde-free.
Designing such a place requires a team of professionals with expertise ranging from structural engineering to energy systems to the psychological effects of space. Importantly, to develop such a place also requires knowledge of sustainable design. Interior design educators understand this need of future designers of the built environment. But how do educators teach students what they need to know to design interior environments that are ecologically healthy? How do educators educate themselves about this? Various resources exist to advise product selection based on specific criteria, but until a clearinghouse for materials is developed, ill-advised decisions are made everyday by interior design students and practitioners. What is the fundamental information necessary to make informed decisions?
Before, specifying materials in a classroom assignment depended largely on factors such as familiarity with product lines or particular manufacturers, reasonable cost, good quality, appropriateness or fit with a specific project, and whatever short list a computer search generated. Now, additional layers are added to this process: Is it a local material? Is it recyclable? Does it contain recycled content? How does it get here from South America? Was it equitably produced? Is it a biological or technical nutrient? What energy was consumed in its manufacture? Does a recycling or composting infrastructure exist to receive this product at the end of its first useful life? … How do we begin to approach these questions?
One approach is to develop a basic understanding of the substances and materials contained in a product. If a carcinogen is revealed, then there is no need to investigate whether or not a process exists to compost or recycle the material—i.e., no need to recycle poison, so consider another product. Yet understanding even the basics may be complicated.
A strategy that has been fairly successful in the classroom is to introduce broad categories of chemicals. The Environmental Working Group published in 2005 eight general categories of substances found in the blood and urine of nine volunteers who neither worked with chemicals nor lived near an industrial site. This provides a place to begin that is compelling for two reasons. First, students recognize that the exposure levels of these nine individuals may not be very different from that of their own exposures. And second, if the presence of these chemicals is pervasive in our biology, then perhaps it also is pervasive in the interior environment:
Polychlorinated Biphenyls (PCBS) are mixtures of organic chemicals that are non-flammable, chemically stable, and have high insulating qualities, making them ideal in industrial and commercial applications including paints, plastics and rubber products. PCBs are considered to be persistent bioaccumulative and toxic (PBT) substances that build up in the food chain and accumulate to levels that are harmful to environmental health and carcinogenic to humans.
Dioxin describes a group of chemicals including 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD) that are endocrine disruptors, reproductive toxins, carcinogens and PBTs. They are formed as byproducts of industrial processes including incineration, bleaching paper and pulp with chlorine, and production of materials such as pesticides and polyvinyl chloride (PVC). PVC degrades air quality and is emitted from typical interior materials such as flooring, wallcovering, paint and a variety of interior products such as 3-ring binders, phone cords, toys and shower curtains.
Furans are comparable in toxicity and production to dioxins, although the chemical structure varies somewhat. The most toxic furan, parallel to TCDD is TCDF, 2,3,7,8-tetrachlorodibenzofuran. Like dioxin, furans also are PBTs.
Metals like arsenic, mercury, lead and cadmium all are PBTs known to affect the nervous system, liver and kidneys, and are associated with developmental delays, lowered IQ scores, and cancer. Mercury often is found in typical household items such as batteries, cameras, small appliances and electrical switches. Cadmium enters the environment from mining, industrial processes and incineration. Like mercury, cadmium has many household uses such as batteries, pigments and plastics, and is often used in solar collectors. For those involved with the built environment, most exposure to arsenic is through pressure-treated lumber and exposure to lead is through lead paint.
The most well-known Organochlorine Insecticide was exposed by Rachel Carson in her book, Silent Spring. DDT (dichloro-diphenyl-trichloroethane) and Organophosphate Insecticides, all PBTs, are most likely to enter our bodies through the food chain. However, knowledge of pesticides is important to those designing interior environments who look to natural fibers such as cotton to avoid the problems associated with synthetic materials. Cotton fields, e.g., are reported to receive 25 percent of all pesticides used in the United States. Whether these pesticides are absorbed in our bodies from cotton fabrics is perhaps not as important as the environmental hazard caused by the pervasive use of pesticides or the exposure of cotton farm workers to carcinogens.
Phthalates are a family of chemicals used to soften plastics such as children's toys, adhesives, and floor and wall covering. In healthcare, DEHP [Di(2-ethylhexyl) phthalate] is most often used to soften PVC medical devices including IV bags and tubing, catheters, and enteral nutrition feeding bags. "Plasticizers" in products such as these may be absorbed through the skin, inhaled or ingested, and are associated with reproductive and developmental harm, organ damage, immune suppression and cancer.
Volatile Organic Compounds (VOCs, e.g., formaldehyde) are released from products during use and often are found in pressed wood products and household products including paint and wood preservatives. Importantly, the EPA reports that levels of VOCs average two to five times higher in indoor environments than outdoor. Health effects are directly related to the amount of exposure, but range from allergies to nervous system disorders to cancer.
Asking interior design students, educators or practitioners to understand all this (and more) is a tall order. It is further complicated by questions of trace amounts of these chemicals in a particular material and by levels of exposure. Further, chemical companies are not required to report how their compounds are used or where they might appear in the environment. Yet for a profession bound to protect the health, safety and welfare of the public, there is little choice except to begin the process of knowing the dangers and responsibilities, perhaps even liabilities, of decisions involving the design and development of interior environments.
Anna Marshall-Baker, PhD, is an associate professor and undergraduate program coordinator of interior architecture at the University of North Carolina at Greensboro, and past president of IDEC. She can be reached at (336) 256-0307.