Atmospheric Deposition of PCBs in Northern New Mexico
Courtney A. Perkins1, Donald J. Carlson, III2 and Armand Groffman3
Polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) that are observed globally in environmental media, even in regions that do not have anthropogenic development or industrial activity. PCBs, which have the potential to cause a variety of adverse health effects, have been detected in surface water and storm water runoff in northern New Mexico, a landscape with sparse industry and urban development. Northern New Mexico has a mild, semiarid, continental climate characterized by low precipitation totals dominated by summer monsoons, low relative humidity, and relatively large diurnal and annual temperature ranges. The elevation ranges from 4,000 to just above 13,000 feet. In order to quantify and understand the PCB source term, wet atmospheric deposition (precipitation) samplers were deployed in 2009 and samples have been collected sporadically since then. The automated samplers were deployed at elevations between 6,500 feet on the Pajarito Plateau and 8,700 feet in the Valles Caldera in the Jemez Mountains. Forty-eight wet deposition samples were analyzed for PCBs using the PCB congener method (EPA Method 1668A). Total PCB values for precipitation, summed from congener results, range from a minimum of 0.002 nanograms/Liter (ng/L) to 4.100 ng/L with an average value of 0.656 ng/L, a median value of 0.358 ng/L, and a standard deviation of 0.876 ng/L. Samplers have been retrofitted to include passive dry atmospheric deposition (i.e., particulate and dust) collection, and two dry deposition samples have been collected to date. The data from this project inform on the probable linkage between PCB concentrations in atmospheric deposition and PCB concentrations observed in surface/storm water in Northern New Mexico.
1New Mexico Environment Department, DOE Oversight Bureau, email@example.com 2New Mexico Environment Department, DOE Oversight Bureau, firstname.lastname@example.org 3Los Alamos National Laboratory, Surface Water Program, email@example.com