Plastics In Oceans Decompose, but Release Hazardous Chemicals
Friday, 21. August 2009, 14:01:52
The good news is that plastics in Oceans decompose with surprising speed.
The bad news is that during these processes it releases toxic substances into the water.
Reporting - at the 238th National Meeting of the American Chemical Society (ACS) - a first study to look at what happens over the years to the billions of kilos of plastic waste floating in the world’s oceans, researchers came to the “surprising” discovery that plastics — reputed to be virtually indestructible — decompose with surprising speed. Scientists always believed that plastics in the oceans were unsightly, but a hazard mainly to marine animals that eat or become ensnared in plastic objects. Plastic in the ocean decomposes as it is exposed to the rain and sun and other environmental conditions.
The author described a new method to simulate the breakdown of plastic products at low temperatures, such as those found in the oceans. The process involves modeling plastic decomposition at room temperature, removing heat from the plastic and then using a liquid to extract the BPA (potentially toxic bisphenol A ) and PS oligomer. Typically, he said, Styrofoam is crushed into pieces in the ocean and finding these is no problem. But when the study team was able to degrade the plastic, it discovered that three new compounds not found in nature formed. They are styrene monomer (SM), styrene dimer (SD) and styrene trimer (ST). SM is a known carcinogen and SD and ST are suspected in causing cancer. BPA ands PS oligomer are not found naturally and, therefore, must have been created through the decomposition of the plastic, he said. Trimer yields SM and SD when it decomposes from heat, so trimer also threatens living creatures.
The bad news is that during these processes it releases toxic substances into the water.
Reporting - at the 238th National Meeting of the American Chemical Society (ACS) - a first study to look at what happens over the years to the billions of kilos of plastic waste floating in the world’s oceans, researchers came to the “surprising” discovery that plastics — reputed to be virtually indestructible — decompose with surprising speed. Scientists always believed that plastics in the oceans were unsightly, but a hazard mainly to marine animals that eat or become ensnared in plastic objects. Plastic in the ocean decomposes as it is exposed to the rain and sun and other environmental conditions.
The author described a new method to simulate the breakdown of plastic products at low temperatures, such as those found in the oceans. The process involves modeling plastic decomposition at room temperature, removing heat from the plastic and then using a liquid to extract the BPA (potentially toxic bisphenol A ) and PS oligomer. Typically, he said, Styrofoam is crushed into pieces in the ocean and finding these is no problem. But when the study team was able to degrade the plastic, it discovered that three new compounds not found in nature formed. They are styrene monomer (SM), styrene dimer (SD) and styrene trimer (ST). SM is a known carcinogen and SD and ST are suspected in causing cancer. BPA ands PS oligomer are not found naturally and, therefore, must have been created through the decomposition of the plastic, he said. Trimer yields SM and SD when it decomposes from heat, so trimer also threatens living creatures.
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http://portal.acs.org/portal/acs/corg/content?_nfpb=true&_pageLabel=PP_ARTICLEMAIN&node_id=222&content_id=CNBP_022763&use_sec=true&sec_url_var=region1&__uuid=9ca28f0a-5365-44be-9b67-34aa77382260
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http://www.sciencedaily.com/releases/2009/08/090819234651.htm
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