Arsenic speciation and heavy metal distribution in polished rice grown in Guangdong Province, Southern China

- As(III) was found to be the predominant As species in rice from Guangdong Province.
- Uptake of As(III) was restricted when total As levels were elevated.
- Cd, Cu and Ni in rice were derived from industrial and commercial activities.
- As and Pb in rice were primarily controlled by geogenic source.
- Intake of rice in Guangdong Province could cause health risk to local inhabitants.

Arsenic speciation and heavy metal distributions have been investigated in locally grown rice grains from Guangdong Province, Southern China. A total of 41 polished rice grain samples were collected throughout Guangdong Province. Arsenite (As(III)), as the predominant form found in the rice, was positively correlated (p < 0.01) with total As (tAs) concentration. However, the percentage of As(III) reduced while tAs concentration increased (r = −0.361, p < 0.05), due to restricted accumulation and translocation of As(III) in rice grains at high level of tAs. Statistical and geostatistical analyses were applied to investigate potential origins of heavy metals in rice. Only Cd, Cu and Ni were identified as influenced by anthropogenic sources such as industrial and commercial activities. As and Pb were primarily controlled by natural occurrence. The results of health risk assessment implied that continuous intake of rice grown in Guangdong Province could cause considerably non-carcinogenic and carcinogenic risk to local inhabitants.