Another study has reported that the arsenic concentrations in the surface soils of farm lands surrounding
15 swine farms using ASA as feed additives in Guangdong
province were in the range of 26–56 mg kg1, far exceeding the
background levels of arsenic in surface soils (Wang et al., 2006).
These results consistently indicate that the widespread use of
organoarsenic feed additives in CAFO zones could cause arsenic
pollution of local agricultural soils, which deserves significant
attention