Suffolk/Essex: Concerns over pesticides in Stour
09:00 26 June 2013
Environmentalists have raised concerns after record levels of a toxic pesticide were discovered in a Suffolk river.
A chemical found in slug pellets in quantities up to 100 times the EU limit for drinking water have been identified in the River Stour and Colne catchment area.
Natural England and the Environment Agency, which test the River Stour weekly at 13 sites, have warned farmers that significant rises in levels of the toxin metaldehyde – the active ingredient of slug pellets – were detected in all of the river’s catchment water courses between September last year and this March.
A record level was recorded last November at Langham water treatment works intake, where Essex and Suffolk Water extracts for its drinking water supply.
Last night, a spokesman for the water company said there was no risk to human health from the levels of metaldehyde detected in the Stour.
He said: “The average size person would have to drink more than 1,000 litres of water each and every day of their life for these levels to have any affect whatsoever.
“It is irresponsible to suggest that there was any form of health concern for customers. Our absolute priority is supplying water that our customers can be confident is completely safe to drink.”
An Environment Agency spokesman said slug pellets put down during heavy rainfall last year led to the high concentrations of metaldehyde being traced in the River Stour in November 2012, but that these levels had since fallen.
The exceptional weather conditions last winter also led to unusually high levels of other agricultural herbicides and pesticides in the Stour, including copyralid, propyzamide, carbetamide and bentazone.
But Environment Agency water resources manager Richard Thompson is confident no harm has been caused to wildlife as a result.
He said: “At its highest level, the concentration of metaldehyde (in the Stour) posed no risk to river ecology. Our scientists found that concentrations are several orders of magnitude less than required to cause ecological harm.”
Farmers have been urged to follow the voluntary EU guidelines laid down to minimise slug pellet use this autumn when crop sowing gets under way.
But environmental campaigners say the voluntary code is not sufficient and they are calling for stricter rules.
Robert Lindsay, of Babergh Green Party, said: “Essex and Suffolk Water no doubt believes that levels of this toxin in drinking water are not high enough to directly damage human health. But the EU has set high standards because nobody knows what harm these toxins will do if they build up in river ecosystems – in the bodies of fish, for example.”