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EPA Says it is more dangerous than we thought!

Posted in Uncategorized by Administrator on the April 1st, 2012

Based upon new research from the EPA which has been reviewed by an independent team of scientists, the cancer causing potency of coal tar sealants may be going up–a lot! How much? Over 800% higher!

Basically the report seeks to update our understanding of the carcinogenic potential of polycyclic aromatic hydrocarbon (PAH) mixtures like coal tar sealants and other solutions (oils, products, smoke, etc.). The EPA sent it out for a draft review in Feb 2010. In March 2011 a review by leading non-EPA scientists was completed on the validity of the findings. In general they found the assumptions and approach adequate, but asked for more research. How or if EPA will address these recommendations is unclear.

The EPA recommends the addition of 18 more PAH chemicals to the relative potency factor (RPF) calculation. Some of these chemicals are not widely tested for and it is difficult to say the impact on the RPF, but there is enough information to estimate a minimum potential increase. Contrary to what the sealant industry has said in public, these factors are going up. The EPA scientists find that PAH mixtures are more toxic than was believed to be when they were proposed in 1993.

My calculations indicate the RPF for an average coal tar sealant will increase at a minimum over 800% over current potency estimations with the real chance of going higher with additional information! That’s big. How would this affect human health and sealants? They maybe more likely to cause cancer than was previously estimated, but there are additional questions that the independent scientists asked the EPA that may affect the cancer potential of specific exposure types.

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