Investigation into perfluoroalkyl substances (PFASs) in a cranberry bog: method development and sampling results.

The contamination of groundwater and surface water from previous uses of perfluoroalkyl substances (PFASs), particularly products containing the contaminants perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), has become a concern for drinking water and as a potential exposure route to the food supply. In 2016, the Food and Drug Administration (FDA) was asked to investigate a bog in Massachusetts where the surface water was believed to be contaminated with PFASs. As a result, a method was developed for the analysis of PFASs in cranberries, and water and fruit from the affected bog were evaluated. A QuEChERS method was developed and validated for PFOA, PFOS, and six additional shorter-chain PFASs. Method recoveries ranged from 60% to 115% for validation spikes performed at 10, 20 and 40 ng g-1 and method detection limits ranged from 0.2 to 5.6 ng g-1 . Bog water samples were analysed using Environmental Protection Agency (EPA) method 537 for PFOA, PFOS and four additional short-chain PFASs. Surface water concentrations for PFOS ranged from 16 to 122 ng L-1 and input water concentrations were 132 ng L-1 and 206 ng L-1 . Of the eight water samples, seven had water concentrations that exceeded the EPA health advisory level for PFOS of 70 ng L-1 . Of the 42 cranberry samples analysed, none had detects of PFOA or PFOS above their method detection limits (0.4 and 0.5 ng g-1 , respectively), nor any of the other short-chain PFASs.