Robuta

https://pubmed.ncbi.nlm.nih.gov/27054094/
The molluscicide metaldehyde (2,4,6,8-tetramethyl-1,3,5,7-tetraoxocanemetacetaldehyde) is an emerging pollutant. It is frequently detected in surface waters,...
for measuringsurface waterimprovedmethodmetaldehyde
https://www.gov.uk/government/news/outdoor-use-of-metaldehyde-to-be-banned-to-protect-wildlife
Restrictions on the use of metaldehyde
to beoutdoorusemetaldehydebanned