Since 1950, plastics have quickly and quietly entered the lives and bodies of most people and ecosystems on the planet. In the United States alone, more than 45.5 billion kilos of resins are formed each year into food and beverage packaging, electronics, building products, furnishings, vehicles, toys, and medical devices. In 2007, the average American purchased more than 100 kilos of plastic, creating nearly US$400 billion in sales.
It is now impossible to avoid exposure to plastics. They surround and pervade our homes, bodies, foods, and water supplies, from the plastic diapers and polyester pyjamas worn by our children to the cars we drive and the frying pans in which we cook our food.
The ubiquitous nature of plastics is a significant factor in an unexpected side effect of 20th century prosperity - a change in the chemistry of the human body. Today, most individuals carry in their bodies a mixture of metals, pesticides, solvents, fire retardants, waterproofing agents, and by-products of fuel combustion, according to studies of human tissues conducted across the US by the Centers for Disease Control and Prevention. Children often carry higher concentrations than adults, with the amounts also varying according to gender and ethnicity. Many of these substances are recognised by the governments of the US and the European Union to be carcinogens, neurotoxins, reproductive and developmental toxins, or endocrine disruptors that mimic or block human hormones.
Significantly, these chemicals were once thought to be safe at doses now known to be hazardous; as with other substances, the perception of danger grew as governments tested chemicals more thoroughly. Such is the case with Bisphenol-A (BPA), the primary component of hard and clear polycarbonate plastics, which people are exposed to daily through water bottles, baby bottles, and the linings of canned foods.
Given the proven health threat posed by some plastics, the scattershot and weak regulation of the plastics industry, and the enormous environmental costs of plastics - the plastics industry accounts for 5 per cent of the nation’s consumption of petroleum and natural gas, and more than 0.45 trillion kilos of plastic wastes now sit in US garbage dumps - the time has come to pass a comprehensive national plastics control law.
One might assume the United States already has such a law. Indeed, Congress adopted the Toxic Substances Control Act (TSCA) in 1976 intending to manage chemicals such as those polymers used to form plastics. Yet TSCA was and is fundamentally flawed for several reasons that have long been obvious. Nearly 80,000 chemicals are now traded in global markets, and Congress exempted nearly 60,000 of them from TSCA testing requirements. Among 20,000 new compounds introduced since the law’s passage, the US Environmental Protection Agency (EPA) has issued permits for all except five, but has required intensive reviews for only 200. This means that nearly all chemicals in commerce have been poorly tested to determine their environmental behaviour or effects on human health. The statute’s ineffectiveness has been recognised for decades, yet Congress, the EPA, and manufacturers all share blame for the failure to do anything about it.
In contrast, the European Union in 2007 adopted a new directive known as “REACH” that requires the testing of both older and newly introduced chemicals. Importantly the new regulations create a burden on manufacturers to prove safety; under TSCA the burden rests on EPA to prove danger, and the agency has never taken up the challenge. Unless the US chooses to adopt similar restrictions, US chemical manufacturers will face barriers to their untested exports intended for European markets. Thus the chemical industry itself recognises the need to harmonise US and EU chemical safety law.
The most promising proposal for reform in the US is the “Kid-Safe Chemical Act”, a bill first introduced in 2008 that would require industry to show that chemicals are safe for children before they are added to consumer products. Such a law is needed because there is little doubt that the growing burden of synthetic chemicals has been accompanied by an increase in the prevalence of many illnesses during the past half-century. These include respiratory diseases (such as childhood asthma), neurological impairments, declining sperm counts, fertility failure, immune dysfunction, breast and prostate cancers, and developmental disorders among the young. Some of these illnesses are now known to be caused or exacerbated by exposure to commercial chemicals and pollutants.
Few people realise how pervasive plastics have become. Most homes constructed since 1985 are wrapped in plastic film such as Tyvek, and many exterior shells are made from polyvinyl chloride (PVC) siding. Some modern buildings receive water and transport wastes via PVC pipes. Wooden floors are coated with polyurethane finishes and polyvinyl chloride tiles.
Foods and beverages are normally packaged in plastic, including milk bottles made from high-density polyethylene. Most families have at least one “non-stick” pan, often made from Teflon, a soft polymer that can scratch and hitchhike on foods to the dinner table. Between 1997 and 2005, annual sales of small bottles of water - those holding less than one litre - increased from 4 billion to nearly 30 billion bottles.
The billions of video games, computers, MP3 players, cameras, and mobile phones purchased each year in the United States use a wide variety of plastic resins. And the almost 7.5 million new vehicles sold in the United States each year contain 1.14 billion kilos of plastic components, which have little hope of being recycled, especially if made from polyvinyl chloride or polycarbonate.
The chemical contents of plastics have always been a mystery to consumers. Under federal law, ingredients need not be labelled, and most manufacturers are unwilling or unable to disclose these contents or their sources. Indeed, often the only clue consumers have to the chemical identity of the plastics they use is the voluntary resin code designed to identify products that should and should not be recycled - but it offers little usable information.