Neonicotinoid pesticides are [ prevalent in waterways in the US midwest and sometimes reach toxic levels ]( http://commondreams.org/news/2014/07/24/notorious-neonics-pervasive-midwest-waters-study ) . They also persist from previous years.
Ссылка: https://stallman.org/archives/2014-may-aug.html#29_July_2014_%28Neonicotinoid_pesticides_prevalent_in_waterways_in_the_US%29