Related Experiment Video
Updated: Aug 25, 2025
Long-term Behavioral and Reproductive Consequences of Embryonic Exposure to Low-dose Toxicants
Published on: March 6, 2018
Evaluation of Neurotoxicity in BALB/c Mice following Chronic Exposure to Polystyrene Microplastics
Haibo Jin1,2,3, Chen Yang4, Chengyue Jiang1,2,3
1Immunology and Reproductive Biology Laboratory, Medical School, Nanjing University, Nanjing, Jiangsu, China.
Background:
The toxicity of microplastics (MPs) has attracted wide attention from researchers. Previous studies have indicated that MPs produce toxic effects on a variety of organs in aquatic organisms and mammals. However, the exact neurotoxicity of MPs in mammals is still unclear.
Objectives:
We aimed to confirm the neurotoxicity of chronic exposure to polystyrene MPs (PS-MPs) at environmental pollution concentrations.
Methods:
In the present study, mice were provided drinking water containing and PS-MPs with diameters of 0.5, 4, and for 180 consecutive days. After the exposure period, the mice were anesthetized to gain brain tissues. The accumulation of PS-MPs in brain tissues, integrity of the blood-brain barrier, inflammation, and spine density were detected. We evaluated learning and memory ability by the Morris water maze and novel object recognition tests.
Results:
We observed the accumulation of PS-MPs with various particle diameters (0.5, 4, and ) in the brains of exposed mice. Meanwhile, exposed mice also exhibited disruption of the blood-brain barrier, higher level of dendritic spine density, and an inflammatory response in the hippocampus. In addition, exposed mice exhibited cognitive and memory deficits compared with control mice as determined using the Morris water maze and novel object recognition tests, respectively. There was a concentration-dependent trend, but no particle size-dependent differences were seen in the neurotoxicity of MPs.
Conclusions:
Collectively, our results suggested that PS-MPs exposure can lead to learning and memory dysfunctions and induce neurotoxic effects in mice, findings which have wide-ranging implications for the public regarding the potential risks of MPs. https://doi.org/10.1289/EHP10255.
Insights
Polystyrene microplastics (PS-MPs) accumulate in mouse brains, impairing learning and memory. This study confirms PS-MPs cause neurotoxic effects and disrupt the blood-brain barrier, highlighting potential public health risks.
Area of Science:
- Environmental toxicology
- Neuroscience
- Mammalian toxicology
Background:
- Microplastic (MP) toxicity is a growing concern, with known effects on aquatic organisms and mammals.
- The specific neurotoxic effects of MPs in mammals remain largely uncharacterized.
Purpose of the Study:
- To investigate the neurotoxicity of chronic exposure to polystyrene microplastics (PS-MPs) at environmentally relevant concentrations.
- To assess the impact of PS-MPs on brain tissue, blood-brain barrier integrity, and cognitive function in mice.
Main Methods:
- Mice were exposed to varying concentrations of PS-MPs (0.5, 4, and ) in drinking water for 180 days.
- Brain tissues were analyzed for PS-MP accumulation, blood-brain barrier integrity, inflammation, and dendritic spine density.
- Cognitive and memory functions were evaluated using the Morris water maze and novel object recognition tests.
Main Results:
- PS-MPs were detected in the brains of exposed mice, with particle accumulation observed.
- Exposure led to blood-brain barrier disruption, increased dendritic spine density, and hippocampal inflammation.
- Mice exposed to PS-MPs showed significant deficits in learning and memory compared to controls.
Conclusions:
- Chronic exposure to PS-MPs induces neurotoxic effects in mice, including cognitive and memory impairments.
- These findings suggest potential risks to public health associated with microplastic exposure.
- The study indicates a concentration-dependent neurotoxic trend, but no significant particle size-dependent effects were observed.
