Selenium speciation in crops from an endemic selenium poisoning area: A case study in Naore village, Shuang'an township, China.

The village of Naore in Shuang'an Township, China, is a unique area with high levels of selenium (Se) in the soil, which has led to incidents of Se poisoning among the local population. To better understand the relationship between Se levels in crops and the risk of Se poisoning, a study was conducted to analyze the content and speciation of Se in 95 crop samples from Naore Village and its surrounding areas. The study included 11 types of commonly consumed local crops and examined the levels of total Se (tSe), organic Se (orgSe), inorganic Se (inorgSe), and various enzyme-soluble Se species. The results showed that the tSe content in crops varied widely, ranging from 0.008 to 165.645 mg/kg, with an average of 5.362 mg/kg. The study also found that different types of crops had varying abilities to accumulate Se, with pakchoi showing the highest levels of Se accumulation, reaching up to 165.465 mg/kg at the Se poisoning site. Organic Se (orgSe) was the predominant form of Se in crops, accounting for over 50% of the total Se content in 95.88% of the samples. Furthermore, the predominant form of orgSe in crops was SeMet. The study's findings suggest that consuming locally produced grains and vegetables with high Se levels can lead to excessive daily Se intake, increasing the risk of Se poisoning. In fact, at the Se poisoning site, the intake of orgSe from locally produced grain and pakchoi exceeded the tolerable limit, highlighting the potential risks associated with orgSe consumption. The study's results are expected to contribute to a better understanding of the potential risks of orgSe and provide a basis for establishing reasonable dietary intake guidelines for orgSe. Overall, the study emphasizes the importance of monitoring Se levels in crops and promoting safe dietary practices to mitigate the risk of Se poisoning in areas with high Se levels. Link: https://pubmed.ncbi.nlm.nih.gov/40356088/