Transformation and removal pathways of four common PPCP/EDCs in soil

Pharmaceutical and personal care products (PPCPs) and endocrine disrupting chemicals (EDCs) enter the soil environment via irrigation with treated wastewater, groundwater recharge, and land application of biosolids. The transformation and fate of PPCP/EDCs in soil affects their potential for plant uptake and groundwater pollution. This study examined four PPCP/EDCs (bisphenol A, diclofenac, naproxen, and 4-nonylphenol) in soil by using C-14-labeling and analyzing mineralization, extractable residue, bound residue, and formation of transformation products. At the end of 112 d of incubation, the majority of C-14-naproxen and C-14-diclofenac was mineralized to (CO2)-C-14, while a majority of C-14-bisphenol A and C-14-nonylphenol was converted to bound residue. After 112 d, the estimated half-lives of the parent compounds were only 1.4-5.4 d. However a variety of transformation products were found and several for bisphenol A and diclofenac were identified, suggesting the need to consider degradation intermediates in soils impacted by PPCP/EDCs. (C) 2014 Elsevier Ltd. All rights reserved.