Abstract:

In order to explore the pollution status and health risks of heavy metals in rice grains in a county of southern Henan, 68 rice grain samples were collected in the area in September 2021. The contents of chromium, arsenic, cadmium, lead, and mercury were determined by inductively coupled plasma mass spectrometry (ICP-MS-TQ) and direct mercury detection. The risk degree of heavy metals in rice was evaluated by single factor and Nemerowcomprehensive pollution index method, and the potential health risk of heavy metals from rice grains was evaluated by target hazard quotient (THQ) promoted by US EPA. The results showed that the average content of heavy metals in 68 rice grains did not exceed the Chinese Food Hygiene Standards, but the arsenic and cadmium contents in some samples exceeded the standards. The comprehensive pollution index (P_N) of heavy metals in rice grain was 0.49, which was safe. ADD of adults and children was higher than RfD, and hazard quotients (HQ) of As were 3.11 and 4.80, which indicated that there was a certain risk of arsenic content in rice grains. The total hazard index (HI) of heavy metals to the exposed population was greater than 1, indicating that the long-term consumption of the rice by local residents may cause adverse health effects. In summary, the rice grain samples in the research area have been contaminated with arsenic, posing certain health risks. The local government needs to strengthen dynamic monitoring of the rice planting process, pay attention to the changes in the form and effective state of arsenic, ensuring food security.

Key words: rice grain, heavy metal pollution, pollution assessment, health risk assessment, food safety