Selected neonicotinoids and associated risk for aquatic organisms

Neonicotinoids are one of the newest groups of systemic pesticides, effective on a wide range of inverte-brate pests. The success of neonicotinoids can be assessed according to the amount used, for example, in the Czech Republic, which now accounts for ' of the insecticide market. The European Union (EU) has a relatively interesting attitude towards neonicotinoids. Three neonicotinoid substances (imidacloprid, clothianidin and thiamethoxam) were severely restricted in 2013. In 2019, imidacloprid and clothianidin were banned, while thiamethoxam and thiacloprid were banned in 2020. In 2022, another substance, sulfoxaflor, was banned. Therefore, only two neo-nicotinoid substances (acetamiprid and flupyradifurone) are approved for outdoor use in the EU. Neonicotinoids enter aquatic ecosystems in many ways. In European rivers, neonicotinoids usually occur in nanograms per litre. Due to the low toxicity of neonicotinoids to standard test species, they were not expected to significantly impact the aquatic ecosystem until later studies showed that aquatic invertebrates, especially insects, are much more sensitive to neonicotinoids. In addition to the lethal effects, many studies point to sublethal impacts -reduced reproductive capacity, initiation of downstream drift of organisms, reduced ability to eat, or a change in feeding strategies. Neonicotinoids can affect individuals, populations, and entire ecosystems.

Automated summary

Neonicotinoids, a new group of systemic pesticides effective against a wide range of pests, have faced severe restrictions and bans in the European Union due to their negative impact on aquatic ecosystems and aquatic invertebrates. Only two neonicotinoid substances are approved for outdoor use in the EU. These pesticides not only have lethal effects on organisms but also lead to sublethal impacts, such as reduced reproductive capacity and altered feeding strategies.