Presented on April 27, 2022, by Lynda Peter - Purdue University - at the 2022 Emerging Contaminants in the Environment Conference (ECEC22)
Biosolids are widely used as soil amendments due their high nutrient contents and ability to improve soil physio-chemical properties; however, not without some environmental concerns. More recently, there have been rising concerns about potential groundwater contamination with per- and polyfluoroalkyl substances (PFAS) leaching from lands receiving biosolids. This study compared PFAS leaching between biosolids applied to an artificially constructed soil in its natural state and biosolids blended with mulch. Leachates were collected over the period of 2 years from zero-tension drainage lysimeters installed 15 cm below the soil surface. They were spiked with isotopically labeled PFAS, and then processed through a solid-phase extraction for quantification using liquid chromatography MS/MS. Concentrations of quantifiable PFAS in leachates corresponded with PFAS levels in treatments. Blending biosolids with mulch at a 0.75:1 ratio reduced PFAS loads in leachates by approximately 30%. Conversely, temporal trends and distribution of PFAS species were similar between both treatments with short chain perfluoro acids (less than C7) dominating in both instances. The overall result suggests that sustainable strategies that dilute PFAS loads in biosolids should be explored for the beneficial reuse of biosolids.
Download slides:
http://hdl.handle.net/2142/114137
…Read more
Less…