The dietary risk assessment of perfluorooctanoic acid (PFOA) and perfluorosulfonic acid (PFOS) in the root crops from the survey of the residue in agricultural soil and the crops

Abstract

Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) are persistent organic pollutants (POPs) that are prohibited from being produced and used. However, they remain in the agricultural environment and are transferred to crops. In addition, PFOA is classified as possibly carcinogenic to humans. To fully understand the exposure and risk of PFOA and PFOS for human in crops, a residue survey and estimation of dietary exposure assessment are needed. Therefore, we investigated the residues of PFOA and PFOS in upland soil and cultivated root crops. The average residues of PFOA and PFOS in the soil were < 0.054-0.541 mu g kg(-1) and 0.024-0.111 mu g kg(-1), and 0.067-0.193 mu g kg(-1) and < 0.02 mu g kg(-1) in the crops, respectively. The average PFOA residues were higher than PFOS in the soil and crops. The estimated daily intakes of PFOA and PFOS in the crops were 0.284 ng kg(bw)(-1) day(-1) and 0.023 ng kg(bw)(-1) day(-1), and the estimated hazard quotients were 0.355 and 0.013, respectively. In addition, the excess cancer risk of PFOA was calculated to be 1.99 x 10(-8). Thus, the non-carcinogenic and carcinogenic risks of PFOA and PFOS were not notable from the surveyed residues in the crops. However, the risks may be higher when the residues in other food crops are considered.