§ Mr. John GarrettTo ask the Secretary of State for the Environment if he will provide in theOfficial Report the most recent sampling data for medium, mean and maximum values of mercury in fish and eels downstream of the Whitlingham sewage treatment works in the River Yare, Norfolk.
§ Mr. HowardThe most recent analyses of mercury in fish flesh carried out by Anglian water authority were in 1985 and 1986. The results were:
December 1985 December 1986 Sample Fish Eels Roach and Pike Number of Samples 28 17 Mean 0.48 0.43 Maximum (mg/Kg wet flesh) 1.21 2.35 The amount of mercury entering the river has been reduced considerably in recent years, and the concentrations in the water column of the river are now regularly below the limit of detection.
The improvement can be illustrated by the decline in the concentration of mercury in sediment samples:
265W
Year Mean (mg/Kg) 1986 6.5 1987 3.2 1988 0.5 A further survey of eels and fish is planned for later this year.