An Environmental Assessment: Microplastics
Typically less than 5 mm in size, microplastics are minuscule plastic particles that infiltrate the environment via various sources including commercial products like cleaning agents, cosmetics, fertilizers, and pharmaceuticals, as well as the degradation of larger plastic items. Due to their inert chemical properties and light weight, microplastics can travel long distances — easily crossing air, land, freshwater, and the ocean.
However, with being pervasive in the environment, the heightened presence of these particles increases the potential risks to human health through exposure.
Ongoing Research
Microplastics’ pathophysiological effects are influenced by factors such as size, dose, duration of exposure, polymer type, surface chemistry, and hydrophobicity. The accumulation of microplastics can harm various organs and organ systems. While previous studies have highlighted the potential ecosystem threats posed by microplastics, recent research suggests toxic effects at the organ and tissue levels, leading to severe lung damage, hepatotoxicity, immunotoxicity, and reproductive toxicity.
Humans are perhaps the most exposed organism primarily because they are at the top of the food chain. Although the published literature indicates that human intake of microplastics is quite evident; entry points may be through ingestion, inhalation, or skin contact. However, the complete extent of exposure and associated health implications remain incompletely understood. There have been reports of the presence of microplastics in various parts of the human body, including feces, blood, placenta, lower airway, and lungs. Research on microplastics is still developing, and the lack of universal standards has resulted in a variety of sampling methods, quality control measures, and analysis techniques.
Current Regulations
Despite the wide-ranging sources of microplastics and growing awareness of their environmental impact, regulations addressing their presence have been slow to materialize on a comprehensive scale. While there are currently no federal laws that ban microplastics, existing legislation indirectly addresses the issue by focusing on mitigating plastic pollution.
The Microbead-Free Waters Act of 2015 is a federal law aimed at reducing the amount of plastic entering waterways by prohibiting the manufacture and introduction to interstate commerce of rinse-off cosmetic products that contain microbeads – a common form of microplastic in items like toothpaste and facial scrubs.
While the Clean Water Act (CWA) does not specifically mention microplastics, it provides a framework for controlling pollution in navigable waters that could indirectly target sources of microplastics. The Toxic Substances Control Act (TSCA) also does not directly mention microplastics, but its focus on regulating chemical substances could impact microplastics if they are deemed harmful to human health or the environment.
Multiple states have implemented regulations to address specific sources of microplastic pollution. While the details of each bill may vary, Colorado, California, Connecticut, Illinois, and Wisconsin have enacted measures concerning the use of microbeads in personal care products. Additionally, California and South Carolina have imposed stringent regulations on the storage and handling of plastic resin pellets or powdered coloring for plastics. However, 16 states currently have no microplastics regulation.
At present, there are no specific EPA regulations addressing microplastics. As of January 2024, the EPA’s research is centered on employing analytical chemistry instrumentation to establish the most accurate methodologies for characterizing and quantifying microplastics in sediment and water samples.
Conclusion
Regulatory responses to microplastics are emerging but remain fragmented. Federal laws indirectly target plastic pollution but do not comprehensively address microplastics. State regulations vary, with measures targeting specific sources of microplastic pollution. Despite some progress, challenges such as the lack of universal standards and gaps in EPA regulations persist.
Adopted measures, from product bans to research initiatives, showcase efforts to address microplastic pollution. However, the comprehensive impact of these particles on oceans, wildlife, and human health underscores the need for broader research and actions to effectively mitigate the risks posed by microplastics in the environment.
