However Reuters claims that an executive summary of the unreleased report does not specifically address the controversial measure though it does confirm their probable toxicity. The EPA proposal is being contested by GE which will have to foot the bill for the dredging programme.

PCBs have been used in transformers, liquid-cooled electric motors and heat transfer systems. They have been identified as possible causes of a number of illnesses including cancer and reproductive and neurological diseases. The materials were manufactured in the USA between 1929 and 1977.

The EPA has identified former GE factories along the Hudson River near the New York State capital, Albany, as sources of contamination between the mid-1940s and 1977 when toxic waste was released into the river. The agency wants GE to spend $490 million on targeted dredging. However the company is resisting the move, which is not final but require further review by the public and businesses.

New York Republican politician John Sweeney has supported the company’s stand, claiming that the initial report from the Academy of Sciences does not support the dredging plan. He supports a more thorough review of the plan before it is implemented.