INCREASING numbers of male fish are being 'feminised' by hormones found in sewage effluent in rivers in the North West.

The latest research carried out by the Environment Agency has shown that oestrogenic steroids - hormones found in sewage effluent - have in some cases caused male fish to develop eggs within their reproductive organs, hindering their ability to reproduce.

Over the next two years the EA plans to identify which sewage treatment works discharge oestrogens at levels which affect fish.