Thursday, October 14, 2010

Is This The New PCB?

In a time when people are becoming more and more aware of the environmental impact of their daily lives, more and more questions are being asked. This enthusiasm and interest is helping move towards a healthier and more sustainable future, however much work and study remains to understand all of our effects on the world around us. There have been incidents set in the past, such as the widespread use of DDT and PCB’s (Ross, et al., 2009), which we have learned from and regulations have been strengthened and tightened.

Peter Ross and a team from all over Canada issued a recent study in the Marine Pollution Bulletin in 2009. The study was conducted concerning a chemical called polybrominated diphenyl ethers or PBDE’s and its effects on aquatic life. The chemical in question is commonly used as a flame retardant in industrial manufacturing of foam mattresses and furniture (Ross, et al., 2009). The chemical is generally sold in three forms: Penta, Octa and Deca. PBDE’s are structurally similar to PCB’s and have to potential to harm food chains and ecosystems in similar ways to PCB’s. The forms of Penta and Octa have been realized as a harmful and were removed from the market places in Europe in 1998 and from North America in 2004 (Ross, et al., 2009). The third form deca remains unregulated in Europe, Canada and the United States (Ross, et al., 2009).

source:(Ross, et al., 2009)

The main component in the deca-BDE is BDE-209 congener (a congener is one of many variants of a common chemical (Green Facts)). The article outlines the authors concerns about the effects of BDE-209 and its persistence, bioaccumulation, toxicity and the possibility of long-range environmental transport and its continued widespread use in North America (Ross, et al., 2009).

The study found that BDE-209 is persistent in the environment. The chemical is transported by means of water pathways, including wastewater, landfill leaching and atmospheric deposition (Ross, et al., 2009). The PBDE’s do not readily break down and their presence in the environment can be traced by depth profiling. From looking at samples taken, it is clear that the presence and concentrations of the chemical mirror its manufacturing history. As surface sediments are mixed with contaminants of PBDE there is a chance that it will re-enter the aquatic food webs and therefore continue to build up rather than being buried under more sediment (Ross, et al., 2009).

The concentration of PBDE in marine mammals can double within 3-4 years in some areas (Ross, et al., 2009). In other areas the contamination puts at risk species on the lower and upper levels of the trophic aquatic food chain (Ross, et al., 2009). The presence of the PBDE’s the body have very similar effects as the structurally similar PCB. PCB's were discontinued in the 1970’s and remain in the environment today. Exposure to PCB’s has been linked to cancer and complications with the immune, respiratory and nervous systems (Groc, 2005). Long-range environmental transport is also a major concern. The study found that PBDE’s are found in remote locations around the world including the Canadian arctic (Ross, et al., 2009).


PBDE is rapidly becoming the new PCB of the world. It reacts similar in the environment and increasing rapidly in concentration in biotic and abiotic materials (Ross, et al., 2009). The concentrations in sewage sediments and water near urban parts of Canada has surpassed the levels of PCB and is projected to become the highest contaminant in fish and marine mammals within ten years if something is not changed (Ross, et al., 2009). The most eye opening concept of the study is that even if production and distribution of deca-PBDE is put to a stop today, there is enough of it already in circulation to ensure the continued delivery to the environment, and therefore the unregulated flame retardants known as PBDE’s with continue to circulate through the environment and into the aquatic food chains for decades (Ross, et al., 2009).

Works Cited
Green Facts. (n.d.). Glossary. Retrieved from Green Facts: /glossary/abc/congener.htm
Groc, I. (2005, November 1). PBDE’s: From the household to the ocean. Retrieved October 12, 2010, from Wild Whales:
Ross, P. S., Couillard, C. M., Ikonomou, M. G., Johannessen, S. C., Lebeuf, M., Macdonald, R. W., et al. (2009). Large and growing environmental resevoirs of Deca-BDE present an emerging health risk for fish and marine mammals. Elsevier (58).

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