Human HaCaT Cell Toxicity Associated with Oxidative Stress on the Polished Rice Grown Adjacent to Abandoned Mines and Potential Health Risk through Rice Intake

Human HaCaT cell viability, total antioxidants generation, and activities of antioxidant enzymes, i.e. superoxide dismutase (SOD) and catalase (CAT), were estimated on contaminated polished rice grown in abandoned mines. Potential health risk by intake of contaminated polished rice causing cytotoxicity on human HaCaT cell was assessed using the Monte-Carlo simulation. Results showed that the HaCaT cell viability in toxic elements (TEs)-contaminated polished rice was inhibited in a time-dependent manner, ranging from 5-25%. Likewise, time-dependent total antioxidants in contaminated polished rice were significantly decreased to 13-22 mM at 72 h post-incubation than in control demonstrating that the mine-impacted polished rice was associated with oxidative damage and decrement of the total antioxidants. The enzyme activities of scavenging reactive oxygen species, i.e. SOD and CAT were 2-4 folds induced compared to control. Assuming that TEs-contaminated polished rice inducing cytotoxicity on HaCaT cell was ingested by human population, no health risk is expected.