0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Human Health Effects Sign in to save

Acute and chronic ingestion of polyethylene (PE) microplastics has mild effects on honey bee health and cognition

Environmental Pollution 2022 94 citations ? Citation count from OpenAlex, updated daily. May differ slightly from the publisher's own count. Score: 60 ? 0–100 AI score estimating relevance to the microplastics field. Papers below 30 are filtered from public browse.
Paride Balzani, Giorgia Galeotti, Sara Scheggi, Alberto Masoni, Giacomo Santini, David Baracchi

Summary

Researchers tested how ingesting polyethylene microplastics affected honey bee survival, feeding, and cognitive abilities at different concentrations and exposure lengths. The study found that high concentrations increased bee mortality and altered feeding behavior, but learning and memory remained largely intact. These results suggest that while bees are not completely unaffected by microplastic ingestion, the cognitive impacts appear relatively mild compared to other health effects.

Polymers

The massive use of plastic has contributed to huge quantities of hazardous refuse at a global scale and represents one of the most prominent issues of the Anthropocene. Microplastics (MPs) have been detected in almost all environments and pose a potential threat to a variety of plant and animal species. Many studies have reported a variety of effects, from negligible to detrimental, of MPs to aquatic organisms. Conversely, much less is known about their effect on terrestrial biota, and particularly on animal behavior and cognition. We assessed the oral toxicity of polyethylene (PE) MPs at three different concentrations (0.5, 5, and 50 mg L), and at different timescales (1 day and 7 days of exposure) and tested for their effects on survival, food intake, sucrose responsiveness, habituation to sucrose and appetitive olfactory learning and memory in the honey bee Apis mellifera. We found that workers were not completely unaffected by acute and prolonged ingestion of this polymer. A significant effect of PE on bee mortality was found for the highest concentration but not for lower ones. PE affected feeding behavior in a concentration-dependent manner, with bees consuming more food than controls when exposed to low concentration PE. Regarding our behavioral and cognitive experiments, the high concentration PE was found to affect only bees' ability to respond consistently to sucrose but not sucrose sensitivity, habituation to sucrose or learning and memory abilities, even for prolonged exposure to PE. While these last results may look somewhat encouraging, we discussed why caution is warranted before ruling out the possibility that PE particles at environmental concentrations are harmful to honey bees.

Sign in to start a discussion.

More Papers Like This

Article Tier 2

Microplastics reach the brain and interfere with honey bee cognition

Researchers found that microplastics reach honey bee brains and impair cognitive function, with bees exposed to mixed polymer combinations showing disrupted learning and memory abilities, demonstrating that plastic pollution poses a direct threat to pollinator health.

Article Tier 2

Microplastics reach the brain and interfere with honey bee cognition

Researchers found that polystyrene and plexiglass microplastics can reach the brains of honey bees and disrupt their cognitive function, impairing sucrose responsiveness and appetitive olfactory learning and memory at environmentally relevant concentrations.

Article Tier 2

Chronic Exposure to Polystyrene Microplastic Fragments Has No Effect on Honey Bee Survival, but Reduces Feeding Rate and Body Weight

Researchers chronically exposed honey bees with established gut microbiomes to polystyrene microplastic fragments over 15 days and found no effect on survival. However, bees exposed to higher concentrations showed reduced feeding rates and lower body weight. The study suggests that while microplastics may not directly kill bees, they could affect bee nutrition and energy balance over time.

Article Tier 2

Microplastics reach the brain and interfere with honey bee cognition

Scientists fed honey bees microplastics at concentrations found in the environment and discovered that the particles reached the bees' brains by crossing the blood-brain barrier. The microplastics impaired the bees' ability to taste sugar, learn, and form memories, with polystyrene having the most severe effects. This research is concerning because it shows microplastics can cross into the brain of a living organism and directly affect cognitive function, raising questions about similar effects in other species.

Article Tier 2

Acute toxicity of microplastic fibers to honeybees and effects on foraging behavior

Researchers tested the acute toxicity of polyester microplastic fibers on honeybees and their effects on foraging behavior. They found that while the fibers were not acutely lethal at tested concentrations, exposure significantly altered the bees' foraging patterns and food consumption. The study suggests that microplastic contamination in terrestrial environments may subtly impair pollinator behavior, potentially affecting ecosystem health.

Share this paper