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Falling eagles

Environmentalists in Japan have found high levels of hormone-disrupting chemicals, including polychlorinated biphenyls (PCBs) and Dichloro dimethyl-trichloro ethane (DDT), in dead Golden Eagle chicks and unhatched eggs around the country. Experts say that further tests are needed to find out if these chemicals are responsible for the plummeting breeding rates of the eagle over the past ten years. Some researchers say that recent findings suggest that adult birds, which ingest the chemicals, are passing the compounds on to their offspring.

Researchers measured the concentration of chemicals found in eight unhatched eggs and five birds who died young. The results show that the eggs contained high levels of PCBs and DDT. PCBs were found in the highest concentrations, ranging from 63 to 210 nanogrammes per gramme (ng/g) in the infants and 14 to 65ng/g in the eggs.

Although most of the chemicals detected are now banned in most countries, they are slow to decompose and can persist in the environment for a long time.

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