Trace Chemicals / Microconstituents Update:
Biosolids and POPs & PFASs
NEBRA has just released an Information Update on perfuorinated alkyl substances (PFASs) in biosolids. These chemicals, the most famous of which are PFOS and PFOA, have been in the headlines, as they have been found contaminating groundwater in several locales in New York, Vermont, and New Hampshire where there were past releases around manufacturing facilities that used them. These chemicals were designed to repel spills, for non-stick surfaces, and for fire-fighting foams and have been used for decades in a variety of consumer products.
The concern with PFASs is that their unique, engineered chemistry makes them quite persistent, leachable, and can be air transported, so they are now found around the world in a variety of media, from rain to soils to groundwater. Biosolids, which reflect our community environments, contain traces of PFASes. Research to date indicates that “Land application of biosolids may release trace levels of PFCs into the agricultural soils but it doesn’t seem to be a major source of human exposure” (Hundal et al., 2011). Download this new document from the NEBRA website -> Resources section -> Microconstituents.
Bill Toffey of the Mid-Atlantic Biosolids Association (MABA), a sister non-profit to NEBRA, provides a nice update of current understanding of trace chemicals in biosolids.
The MABA blog includes mention of researchers at AZ State University. Rolf Halden and colleagues have been analyzing biosolids for many years, including looking closely at samples collected through the U. S. EPA Targeted National Sewage Sludge Survey, of which they have frozen samples. Recently, Halden's lab has focused on analyzing wastewater solids to understand city community health.
NEBRA's Resource page on Microconstituents / Trace chemicals has additional information on this "hot" topic.