As per researchers, banned chemical pollutants have been causing breeding problem in porpoises and protected-dolphins. The leading scientists have found high amount of polychlorinated biphenyls (PCBs) in the body fat of 329 harbor porpoises on UK beaches.

The researchers have especially pointed out that Cardigan Bay’s dolphin population is especially at greater risk. Director of the Sea Watch Foundation Dr Peter Evans was of the view that in comparison to porpoises, such chemical pollutants are present in higher amount in bottlenose dolphins.

The scientists think that the chemical, which has been banned in the UK for more than three decades, may be responsible for many stillbirths, miscarriages and instantaneous abortions. The experts affirmed that around a fifth of the sexually mature female porpoises have the signs of reproductive failure. Also, additional 16.5% were found to be having infections or tumors in reproductive organs.

Study’s lead researcher Dr Sinead Murphy, from the Zoological Society of London said that a decline in pregnancy rate was also estimated among healthy females. “Reproductive failure could have occurred in almost 40 per cent of mature females sampled in this study. PCBs may have reduced foetal or newborn survival, something which has also been observed in other mammals”, said Murphy.

There was a time when PCBs were once used in electrical parts and other certain paints. The study researchers said that the chemicals are banned, but are considered to be present in environment for many years.