Metaldehyde is the most widely used pesticide for slug control. 

MSG Statement 

Metaldehyde In River Water

Please click on the links below for the current briefing notes from Water UK.

Water UK Briefing Note 1

Water UK Briefing Note 2 

While detailed catchment studies have yet to be conducted, there are various means by which metaldehyde can find its way into water.

Point sources such as spills during filling the spreader, or when moving bags or sacks of pellets can be washed off or simply run-off into water courses.  We know that this source can lead to around 40% of spray contamination of water courses.

Secondly, inaccurate spreading across field margins, ditches and water courses will also lead to contamination.

In addition, diffuse leaching of metaldehyde can also occur, particularly when pellets are spread onto saturated ground or when rain is imminent. Diffuse leaching into field drains was found to be the most serious mechanism of metaldehyde reaching surface water.