Scientists working for the United Nations Environment Program are reviewing nine chemicals that could be added to the original "dirty dozen" list of banned toxic chemicals.
The Stockholm Convention on Persistent Organic Pollutants banned nine pesticides, as well as common chemicals like PCBs and dioxin. All were banned because they accumulate in the tissues of living things, including humans, because they are all but indestructible once released into the natural world, and because they can spread across the globe with weather patterns and migrating animals. Not to mention that they have been linked to a range of health issues, including cancer and reproductive and developmental problems.
“Chemicals have contributed to human well-being across a range of areas from medicine and foodstuffs to agriculture and industrial processes,” said Achim Steiner, executive director of the UN Environment Program. “However, as science gains greater insight into their effects, we are fast understanding that some substances now pose real risks to humans and the wider environment, often invulnerable communities such as can be found in parts of the Arctic. Eliminating, restricting and accelerating a switch to better alternatives must be our goal.”
The new candidates are used in consumer products, such as flame retardants in textiles and carpets, in fire-fighting foam, and in photo imaging.
Here's a look at the new candidates:
The Nasty Nine
This PBDE congener, sometimes referred to as "penta," was used as a flame-retardant in foam upholstery and furnishing. It was fist banned in Germany, Norway and Sweden in the 1980s and 1990s, then in the Europe Union in 2003. The last U.S. manufacturer stopped producing the chemical in 2005, and the Environmental Protection Agency subsequently banned its production in the U.S. It is still manufactured elsewhere, primarily in China, and can be imported to the U.S. Maine and Washington have banned it and nine other states have proposed bans.
The chemical may cause a range of health problems, including liver disease and reproductive and developmental problems. It has been found in human breast milk.
Like its sister "penta" this polybrominated diphenyl ether, or PBDE, has been linked to health issues and has largely been phased out in developed nations.
This insecticide, also known as Kepone, was used until 1978 in the United States on tobacco, ornamental shrubs, bananas, and citrus trees, and in ant and roach traps. It is chemically almost identical to Mirex, which was one of the original "Dirty Dozen" banned by the treaty.
Workers using chlordecone suffered damage to the nervous system, skin, liver, and male reproductive system. It may still be in use in developing nations, despite its being banned in the industrialized world.
An agricultural insecticide also used to treat headlice and scabies in people, lindane has been banned in 50 nations because the organochlorine pesticide can attack the nervous system. In the United States, it was used until 2007 on farms, and it is still used as a "second-line" treatment for head lice when other treatments fail.
Additionally, because Lindane is the only useful product in a family of chemicals generated to produce the pesticide, there is persistent chemical waste created by the process. For every ton of Lindane produced, six to 10 tons of waste are produced.
One of the persistent chemical waste products produced by making Lindane, alpha-hexachlorocyclohexane may cause cancer, and liver or kidney problems.
Another of the persistent chemical waste products produced by making Lindane, beta-hexachlorocyclohexane may cause cancer and reproductive problems.
The company 3M used PFOS to make Scotchgard fabric and other stain-resistant products until 2002. The chemical is found in the bodies of people around the world, and in relatively high concentrations in Arctic wildlife -- reflecting the global transport of persistent chemicals like these.
A polybrominated biphenyl, or PBB, hexabromobiphenyl is a flame retardant that has been linked to a range of health problems, including weight loss, skin disorders, nervous and immune systems effects, and effects on the liver, kidneys, and thyroid gland. While it is no longer used in developed nations, it may still be in use in developing nations.
Used in the manufacture of an insecticide, and as a flame retardant, Pentachlorobenzene may damage the nervous and reproductive systems, as well as the liver and kidneys. It is also used as a head lice treatment, and can be found in the waste streams of some paper mills, petroleum refineries, sewage treatment plants and incinerators.