Research led by PHF Science on behalf of the Ministry for the Environment, highlights the growing presence of microplastics and nanoplastics in the environment and the need for improved monitoring to better understand their potential impacts on ecosystems and human health.
Microplastics and nanoplastics (MNPs) have been identified throughout the world’s environment, from oceans and freshwater systems to soils, sediments, the air we breathe and inside plants and animals.
These tiny plastic particles include small plastic particles such as glitter and fragments of larger plastic products that break down and wear over time. Their persistence, small size and resulting mobility mean their distribution is large and extends far beyond their source, with exposure routes including food, water and air.
A growing body of international research identifies MNPs as an emerging concern for ecological integrity and human health. While the report does not establish direct evidence of adverse health outcomes in humans, it identifies microplastics and nanoplastics as a credible emerging risk that warrants further research and monitoring.
Studies have identified a range of potential biological effects, including physical impacts on organisms, chemical toxicity from plastic additives and contaminants attached to plastic particles, and changes associated with interactions between plastics and microorganisms. However, understanding the full scale of these impacts remains challenging.
“The challenge with micro and nanoplastics is that they are not a single, uniform pollutant. These particles vary widely in their size, shape, chemical composition, age and the substances they carry with them. As a result, their effects can differ depending on the organism, environment and conditions of exposure,” says the report’s author, Olga Pantos, a Science Leader at PHF Science.
While evidence of MNP exposure and potential biological effects continues to grow, important knowledge gaps remain, particularly around the extent and significance of impacts on human health. Current research suggests that the evidence base is substantial but incomplete, with further work needed to determine the magnitude of risks and the mechanisms involved.
A key priority identified is the establishment of coordinated, routine monitoring of MNPs across environmental systems, including air, water and soils, as well as important sources such as wastewater discharges. Better monitoring would provide a clearer picture of real-world exposure, improve consistency between studies and support research that reflects actual environmental conditions.
With plastics persistent in the environment and few practical options available to remove MNPs once released. The report identifies reducing plastic sources and strengthening monitoring as important considerations for managing potential future risks.
Understanding where microplastics and nanoplastics are found, how they move through the environment and what impacts they may have will be important for informing future responses.