A recent study reveals that exposure to neonicotinoid pesticides has different effects on various body parts of bumble bees, helping to explain the varied detrimental impacts of these pesticides and underscoring the necessity for more precise safety evaluations.
Researchers from Queen Mary University of London found that the neonicotinoid pesticide clothianidin disrupts different areas of bumble bee bodies in notably different ways. Their research indicates that the effects of pesticides are not uniform and that they alter the functions of crucial tissues such as the brain, legs, and kidney-like structures in unique manners.
Different effects on specific tissues
By subjecting bumble bees to a realistic field dose of clothianidin, the scientists observed significant variations in gene activity among body tissues, with 82% of changes being specific to individual tissues.
“Every tissue we studied was significantly impacted by the pesticide,” stated Professor Yannick Wurm. “The wide-ranging effects of pesticide exposure shed light on the complex issues bumble bees face, including mobility issues, impaired learning abilities, and weakened immune responses.”
Neonicotinoid pesticides like clothianidin are commonly used to protect crops from harmful pests. However, previous studies have highlighted that even minimal doses can jeopardize the survival of beneficial insect populations. In this investigation, the researchers employed advanced molecular diagnostic techniques, typically reserved for biomedicine, to identify the specific molecular pathways disrupted by pesticide exposure. For example, they noted changes in brain genes related to ion transport, alterations in muscle-specific genes vital for the hind femur (important for movement), and a reduction in the detoxification gene activity of Malpighian tubules (which function similarly to kidneys).
“These results indicate that traditional risk assessments for pesticides, which often neglect tissue-specific damage, do not adequately account for the sub-lethal effects on pollinators,” explained Dr. Federico López-Osorio, a co-author of the study.
Consequences of tissue-specific damage necessitate urgent action
The researchers stress that these alterations, reminiscent of changes associated with aging and cancer, represent a significant threat to bee health, impacting all tissues in detrimental ways.
“We use pesticides without fully grasping their effects on beneficial insect pollinators,” said lead author Dr. Alicja Witwicka. “Our research demonstrates that all tissues are affected in ways that jeopardize their essential functions, resulting in devastating and widespread consequences. This study serves as a crucial reminder to reassess how we evaluate, manage, and apply pesticides, not just to protect pollinators but also the ecosystems that rely on them.”
The research underscores an immediate need to rethink pesticide safety protocols to avoid further damage to essential pollinators—species that play a vital role in producing many of the fruits and nuts we consume and sustaining biodiversity. This comes at a time when people and governments globally are growing increasingly alarmed about biodiversity loss, aiming for ambitious goals to reverse declines and restore ecosystem health.
