All our fish are turning into girls?
It must be almost 10 years ago when experiments were carried out on fish kept in storage cages on the River Aire, just below the discharge from Esholt Sewage Works and the results showed that the fish, mainly roach, were changing their sex from male to female.
The reason for this phenomenon was all down to the increasing presence of the female hormones from the contraceptive pill and HRT treatment in the river.
Recently new research has been carried out by the Environment Agency on 51 rivers across the UK and they showed that almost a third of the male fish examined were developing female sex organs and producing poor quality sperm.
Experts at Exeter University, who carried out most of the tests, confirmed that the sewage treatment works were unable to remove the cause of the problem, the chemical oestrogen.
The long-term implications for the fish population does not look good if this situation continues and the Exeter boffins reckon that immediate action must be taken to filter out oestrogen at treatment level, otherwise there is a distinct possibility that fish will be unable to breed.
The problem will only occur on rivers, such as the Aire, where there is a discharge from the sewage works into the mainflow, so lakes, canals, ponds and other land-locked waters will be completely safe.
Even so, this is a serious problem and surely the solution should not be too difficult with the scientific resources now available.
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