Effects of organochlorine pesticides (OCPs) on survival and edibility of loaches in the World Heritage Honghe Hani Rice Terraces, China

A study on the UNESCO-listed Honghe Hani Rice Terraces reveals that organochlorine pesticides (OCPs), though banned, persist in the environment and pose minimal risk to human consumption of loaches. Researchers found that while OCPs like DDTs and HCHs were present in water and sediment throughout the rice-loach co-culture season, they were not detected in the muscle tissue of loaches sent to market, suggesting low toxicity for consumers. The study also identified heptachlor as a significant contributor to OCP levels early in the season, potentially affecting loach survival. Sampling across three months showed a decline in total OCPs from May to October, with August and October samples clustering together, indicating environmental persistence. These findings provide critical insights for sustainable aquaculture practices and the preservation of this World Heritage Site.

Song, C., Zhang, J., Hu, G., Yin, Y., Qiu, L., Fan, L., Zheng, Y., Meng, S., Zhang, C., & Chen, J. (2019). Effects of organochlorine pesticides (OCPs) on survival and edibility of loaches in the World Heritage Honghe Hani Rice Terraces, China. Aquaculture Environment Interactions, 11, 239–247. https://doi.org/10.3354/aei00307