Heavy metals and arsenic concentrations in water, agricultural soil, and rice in Ngan Son district, Bac Kan province, Vietnam

Abstract

Due to the fast development in many industries such as metallurgical, mining, and chemical sectors in Vietnam, many issues related to environmental contamination have been raised. This study was conducted to briefly investigate the heavy metal levels in water, agricultural soil, and rice in Thuong Quan commune, Ngan Son district, Bac Kan province, Vietnam. The analytical results of 06 elements such as Arsenic (As), Cadmium (Cd), Copper (Cu), Lead (Pb), Nickel (Ni), and Zinc (Zn) showed the current status of agricultural soil, water, and rice quality in the vicinity of study area. For surface water and domestic water samples, the average level of six elements did not exceed the Vietnam standard. While the As levels in agricultural soil were 15.6 - 27.2 mg/kg which exceeded the Vietnam standard for agricultural soil. On the other hand, the total Arsenic (tAs) levels in rice were 0.18 - 0.40 mg/kg which not exceeded the Vietnam standard for polished rice. Throughout this study, tAs is the only element that needs to be further investigated from the relatively high concentration in agricultural soil samples. There were seven out of eight rice samples which had the As level exceeded the Codex standard for polished rice, the inorganic Arsenic (iAs) is also needed to be analyzed for further conclusion.