HC Deb 05 February 1990 vol 166 c444W
Mr. Alton

To ask the Secretary of State for the Environment what are the maximum levels of(a) mercury and (b) lead allowed in sewage sludge to be dumped at sea.

Mr. Curry

Current United Kingdom licences for disposal of sewage sludge to sea set a maximum total annual input of 2.7 tonnes of mercury and 248 tonnes of lead.

The quantities of these metals entering the North sea in sewage sludge dumping is only about 1 per cent, of the total inputs of these metals to the North sea, most of which result from river discharges from continental countries, atmospheric inputs and disposals of dredged spoil.