Occurrence of phthalate acid esters (PAEs) in protected agriculture soils and implications for human health exposure

Abstract In order to understand the occurrence of phthalic acid esters (PAEs) in protected agriculture soils and assess their potential health risks to humans, this study explored six priority PAEs in representative protected agricultural soils, and conducted a health risk assessment of PAEs homologs in humans. Results showed that bis(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) were the most abundant PAEs congeners in the present study, with mean concentrations of 318.68 µg/kg and 137.56 µg/kg, respectively. Di-n-octyl phthalate (DOP) and butyl benzyl phthalate (BBP) concentrations were relatively low, and dimethyl phthalate (DMP) and diethyl phthalate (DEP) were not detected in all samples. DBP concentrations in soils were higher than the allowable concentration standard value. Additionally, soil pH and organic matter were key environmental parameters which may play the vital roles to the occurrence of organic pollutants. Heath risk assessment results indicated that dermal contact was the predominant human exposure route under non-dietary conditions. Furthermore, children obtained higher health risk scores than adults, suggesting that children may be more vulnerable to PAEs than adults. In summary, the overall health risk scores were at an acceptable level, which revealed PAEs in protected agricultural soils posed an insignificant health risk to neither adults nor children. These results provide insights for assessing soil environmental safety and ecological risks in protected agricultural soil.