Mei found poisons in some fish in lakes and reservoirs

Nearly half of the lakes and reservoirs in the United States contain more metal mercury than the federal government has set, which may affect human health, according to a study released by the US Environmental Protection Agency on the 10th.

The Environmental Protection Agency investigated 500 lakes and reservoirs in the United States between 2000 and 2003, and fish samples were tested for metallic mercury and organic compounds polychlorinated biphenyls. The researchers found that 49% of the fish in lakes and reservoirs surveyed contained more metal mercury than the safety standards set by the EPA.

The results also showed that the content of PCBs in 17% of the fish in lakes and reservoirs exceeded the standard.

According to the researchers, excessive intake of metallic mercury can damage the nervous system and endanger human health. Polychlorinated biphenyls are carcinogens, which are easy to accumulate in human adipose tissue and affect the nervous, reproductive and immune systems.

Researchers believe that thermal power stations are the main source of mercury pollution in lakes and reservoirs.

The EPA says the results of the study show the importance of further reducing mercury pollution. The US government said earlier this year that it would start drafting new rules to control mercury emissions from power stations.