Pesticides may drastically shorten fish lifespans, study finds

"Signs of ageing accelerated when fish were exposed to the chemicals, according to the study, which could have implications for other organisms. Chemical safety regulations tend to focus on short-term exposure to high doses of pesticides and other chemicals, but the study focused on long-term exposure. Low doses of pesticides are widespread in the environment, so their effects should be studied and understood, the authors said."

"Researcher Kai Huang, who also worked on the study, combined field observations of more than 20,000 lake skygazer fish from lakes in China with persistent low levels of the common pesticide chlorpyrifos. The research found that fish from pesticide-affected lakes showed shortened telomeres, the caps at the end of chromosomes that are known as the biological clock for ageing. When they shorten, it is a sign of cellular ageing and a decline in the body's regenerative capacity. The lake populations consisted of younger fish, indicating that the pesticides contributed to shortened lives."

"Laboratory experiments confirmed the findings and showed chronic low-dose exposure reduced fish survival and degraded telomeres. These effects were not seen with acute high-dose exposure. Rohr said: When we examined telomere length and deposition of lipofuscin in the livers of the fish well-established biological markers of ageing we found that fish of the same chronological age were ageing faster in the contaminated than clean lake"

Persistent low-dose exposure to common agricultural pesticides drastically reduces fish lifespan and accelerates biological ageing by shortening telomeres. Field observations of over 20,000 lake skygazer fish in chlorpyrifos-contaminated lakes revealed shortened telomeres and populations skewed toward younger individuals, indicating higher mortality. Chronic low-dose laboratory exposure reduced survival and degraded telomeres, whereas acute high-dose exposure did not produce these effects. Shortened telomeres and increased lipofuscin deposition indicate accelerated cellular ageing and reduced regenerative capacity. Conserved telomere biology across vertebrates suggests that chronic low-dose pesticide exposure could present similar ageing-related risks for other species, including humans.

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