PPCPs consist of a wide range of compounds. Their adsorption
behaviors vary from compound to compound, and are difficult to
predict because their behavior is often controlled by interactions
with specific functional groups or complicated pH-dependent speciation. Their degradation studies were mainly
carried out in aqueous environments (for example biological degradation, photo degradation)in sewage sludge,or in sediments.Few researches were conducted in agricultural soils. This study examines sorptive and degradation properties of six selected PPCPs, namely
clofibric acid, ibuprofen, naproxen, triclosan, diclofenac and
bisphenol A in four US agricultural soils with various physicochemical characteristics. The selected PPCPs were detected in agricultural runoff samples with reclaimed wastewater irrigation (Xu
et al., 2009c), and in reclaimed wastewater irrigated turf grass field
(Xu et al., 2009a), suggesting their introduction from sewage to
soils. Degradation and adsorption as a function of soil types is also
considered here, trying to find out the correlations between the
adsorption/degradation and soil properties. Furthermore, the
mechanism of degradation was investigated through comparative
experiments using sterilized and nonsterile soils. Results from
the present study can help to assess the environmental risks of
PPCPs associated with reclaimed wastewater irrigation in agricultural soils.