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The BIOSCAN project is studying the genetic diversity of 1,000,000 flying insects from across the UK over a five year period. Insects from 100 sites are actively being collected on a monthly basis by project partners and then analysed at the Sanger using DNA barcoding. The resulting sequence data will provide a baseline characterisation of insect species diversity over space and time and thus form a much needed resource for DNA-based biomonitoring in the UK. Visit the project website!

This project presents compelling new evidence challenging the current pesticide safety assessments and highlights the urgent need for updates. We advocate for the widespread integration of genomics and transcriptomics data in the development and testing of both existing and new pesticide compounds.

Pesticides are widely used in agriculture to combat pest insects and protect crops. However, these substances are not species-specific and act as general neurotoxins. This means that they may harm non-target insect species, including pollinators that play a crucial role in agriculture.
It’s well known that pesticides negatively impact pollinators, and some have been restricted in certain regions due to their severe effects. However, we still lack a detailed understanding of how exactly pesticides behave inside insect bodies, which biological processes they disrupt, whether these processes vary across different body parts, and how these effects differ between insect species.
This project aims to address these questions. We use transcriptomics, a method that allows us to study the changes in activity of all genes in an insect’s genome after pesticide exposure. Insects are incredibly diverse in their behavior, anatomy, and physiology, making direct comparisons between species challenging. However, genes are the fundamental building blocks of all organisms, enabling us to compare their responses across species more effectively.
In addition to studying the diversity of pesticide effects, we aim to improve the current assumptions in pesticide safety assessments, which have been criticised for their simplicity and reliance on assumptions.

The current pesticide safety assessment process has three main flaws:
1. Testing is limited to mesaurements of survival of individual insects. However, intoxication by pesticides can significantly reduce an insect's ability to pollinate, reproduce, and survive in the wild, even if the insect is still alive.
2. Testing uses high doses of insecticides over short periods of time, which does not accurately reflect the long-term, chronic exposure to small doses of insecticides that often occurs in agricultural landscapes.
3. Testing only focuses on the honey bee (Apis mellifera) or a few other species, and toxicity measurements are then extrapolated to thousands of other wild pollinators. This ignores the complex differences in life histories and physiologies among pollinating insects.

So far, our research has established that pesticides induce varying effects across different insect tissues. We found that each of the three organs we studied - the brain, legs, and Malpighian tubules (the insect equivalent of kidneys) - reacted differently to pesticide exposure, experiencing disruptions to processes critical to each organ’s function. These findings help explain why pesticide exposure can have such severe impacts on insects.
Moreover, when we exposed one species to two different pesticides (sulfoxaflor and clothianidin), we observed overlapping biological responses, despite the differences in the pesticides' chemical structures. This suggests that different compounds target similar biological processes within an insect species. This is significant because current pesticide regulations are based on chemical composition rather than the biological effects they cause. Furthermore, we observed vast differences in the effects of these pesticides between species, challenging the assumption that pesticide impacts on honey bees can be extrapolated to other species.
We also investigated the impact of different exposure regimes on bumble bees. In nature, insects are likely exposed to minute doses of pesticide residue over much of their lifespan. However, lab testing typically involves extremely high doses over short periods (24–48 hours). We found that the molecular processes affected by these two exposure types differed significantly, and that the exposure regime, rather than the specific pesticide, was the primary driver of the bees’ response.

Visit the project website!