MARCH 2016 RESEARCH SUMMARY

MARCH 2016 RESEARCH SUMMARY

Let’s Get Real about PFOs

A great article in the New York Times magazine story is the lead piece and inspiration for this month’s library. The article reads like a detective story. It is a detective story. It describes the efforts of an attorney to get DuPont to own up to the environmental damage it caused in a town where it manufactured a range of perfluorinated organic chemicals. These are the same compounds that Kern County is arguing make land application of biosolids in that County an environmental liability.

Biosolids is not to blame. Too often in the biosolids world people that use and/or produce biosolids are considered to be the bad players because of the range of compounds that can be detected in the biosolids that are viewed as potential environmental hazards. These compounds, since the pretreatment regulations went into effect several decades ago, typically do not originate in industries that discharge into the municipal system. They typically originate in people’s homes.

PFOs or PFOAs or whatever initials you use for these compounds are no exception. While there was the famous case of the biosolids from the town in Alabama where these compounds were manufactured, in the vast majority of treatment works, these compounds can be traced back to people’s homes and the wide range of household products that they are used in. If the risk associated with using these compounds is greater than the benefits, then rather than questioning the safety of biosolids, it would be best to question the need for the product itself. It is also appropriate to task the manufacturer not the municipality with blame.

That is why I think everybody should read this first piece.

The second article is a review on these compounds, written by an excellent toxicologist in 2002. The article goes into the chemical structure of these compounds and why that makes them unique. It also explains why they are hard to degrade. They are the ‘new’ trendy contaminant in biosolids but have actually been produced for over 60 years. The article also talks about likely mechanisms for spread of the compounds, where they have been seen in animals (pretty much all over with the exception of livers from yellow fin tuna from the North Pacific). It also discusses potential toxicology associated with these compounds.

From here we go to the home. Or rather to an article that tracked occurrence and concentrations of these compounds in common household products in the US from 2007 to 2011. One of the figures shows how they sampled T shirts, popcorn bags, and mattress pads. Talk about ubiquitous. Concentrations have generally gone down over time with decreases seen in both the shorter chain and longer chain versions. Hopefully if the authors of the next study redid their work (study published in 2004) they would see that the decrease in household products would be reflected in a decrease in human blood. In 2004 they were able to measure concentrations in blood in people from the US and Poland (highest), Korea, Belgium, Malaysia, Brazil, Italy and Columbia (moderate) and India (lowest). Then again, microwave popcorn and shag rugs might be trending now in Mumbai.

For the last article we go to the treatment plant. This is an early paper that tracks the flows of different perfluorinated compounds through a wastewater plant in the Pacific Northwest. One of the authors, Chris Higgins, has published extensively on these compounds and the risks they pose in biosolids. They list the different types of compounds and their concentrations (typically in low ppb range) in biosolids. They also provide flow charts that track where each compound goes within the treatment plant including out with the treated effluent or to the solids. Dr. Higgins is an excellent scientist. I bet if he were to team with the lawyer from the first article and if they both were to go after the manufacturers of these and other compounds, we could really get somewhere.

Sally Brown, University of Washington