Over the past few years, there has been increasing concern about microplastic contamination. Annual global plastic production is currently estimated at 460 million tons and is expected to reach 736 million tons by 2040.
What are Microplastics and Nanoplastics?
According to the U.S. Food and Drug Administration (FDA), microplastics are very small pieces of plastic that are typically considered less than five millimeters in size in at least one dimension. Microplastics can be either primary (manufactured to be that size, such as resin pellets used for plastic production) or secondary (degraded to that size from larger plastics discarded into the environment). Nanoplastics are even smaller – typically considered to be less than one micron, in size. For reference, the diameter of a human hair is about 70 microns. Together, micro- and nanoplastics are often referred to as MNPs. They are comprised of many different chemical compositions and/or stages of degradation and can contain chemical additives such as antioxidants, UV stabilizers, fillers, colorants, lubricants, and antistatic agents.
Where are Microplastics and Nanoplastics Found?
MNPs are ubiquitous. They have been found in samples from the highest mountains to the deepest undersea trenches on earth. They have been detected in multiple components of the human food chain – including fish, shellfish, drinking water, fruits and vegetables, salt, sugar, tea bags, and baby bottles. Ingestion is considered the primary route of exposure. The inhalation of house dust containing polybrominated diphenyl ethers, which were used as fire retardants in older plastics and synthetic fabrics, also presents an exposure concern. The chemicals used in the manufacture of plastics, such as phthalates and bisphenols, have been found in biomonitoring samples, including samples from newborns and pregnant women (Zarus, et al, 2021, https://doi.org/10.1016/j.scitotenv.2020.144010). Other plastic-associated chemicals, including PFAS and various additives, have also been detected in human populations. Many of the plastic chemicals in use today have not been evaluated for toxicity in human health studies.
Why the Concern?
Apprehension about plastics, in general, is not new from an environmental perspective. With current production exceeding 400 million tons annually – less than 10% of which comes from recycled plastic waste, with the remainder derived from fossil fuels – the potential for pollution is substantial. Plastics enter the environment at all stages of their life cycle, including manufacture, fabrication, use, and waste management. Because plastics are highly durable, they degrade very slowly and consequently accumulate in oceans and landfills. As plastics degrade, they fragment into MNPs, which tend to be more environmentally mobile and may have greater potential for biological uptake.
The extent to which MNPs cause human harm remains uncertain, and research is constrained by analytical challenges. MNPs have been detected in human tissues – including placenta, blood, lung, arterial plaque, and brain – indicating exposure and systemic distribution. However, the health significance of these findings is not yet clear. Experimental studies suggest MNPs may activate biological pathways such as inflammation, oxidative stress, and endocrine disruption, but causal links to human disease have not been established. Limited human studies report associations with outcomes such as cardiovascular events and reproductive effects, while evidence for neurological and gastrointestinal conditions remains sparse and indirect.
At present, there is significant interest within the scientific community in investigating the synergistic toxicity relationship between MNPs and PFAS in both environmental systems and human cell lines. Some recent studies have linked MNPs with:
- Stroke
- Myocardial infarction
- Endocrine disruption
- Irritable Bowel Syndrome (IBS)
- Intrauterine growth restriction
- Dementia
- Alzheimer’s disease
Industries Contributing to MNPs in the Environment
A wide range of industrial sectors contribute to the release of micro- and nanoplastics into the environment through production processes, product use, and material degradation. Key contributors include:
- Plastic Manufacturing and Pellet Production– Loss of resin pellets and fragments during production, transport, and handling.
- Textile and Fashion Industries– Synthetic fabrics shed microfibers during laundering and routine wear.
- Automotive Sector– Tire abrasion during normal vehicle operation generates significant quantities of microplastic particles.
- Single-Use Plastic Packaging– Fragmentation and improper disposal of packaging materials introduce persistent plastic particles into ecosystems.
- Cosmetics and Personal Care Products– Some formulations, such as certain toothpastes and exfoliating products, contain microbeads that enter wastewater streams.
- Marine and Fishing Industries– Wear and degradation of nets, ropes, and other gear release plastic fibers and fragments into aquatic environments.
- Agriculture and Food Production – Application of sewage sludge, use of plastic mulch films, and irrigation practices can introduce microplastics into soils and waterways.
- Construction and Coatings – Paints, sealants, and other building materials release microplastics through weathering and surface erosion.
Recent Regulatory/Legal Developments
Some recent regulatory and legal events have the potential to impact insurance claims related to MNPs:
The U.S. Environmental Protection Agency (EPA) is currently developing the Sixth Unregulated Contaminant Monitoring Rule (UCMR 6). Scheduled for 2027-2031, the proposal includes monitoring for microplastics in public water systems.
As of January 2026, California’s SB 1053 bans all plastic checkout bags, providing a clearer legal floor for enforcement.
Improved source attribution science “chemical fingerprinting” and oceanographic drift modeling are allowing plaintiffs to link specific plastic waste back to individual producers. This is bridging the “accountability gap” that previously protected companies from liability in diffuse-source pollution cases.
Extended Producer Responsibility laws are scheduled to take effect in early 2026 requiring companies to fund and take responsibility for the entire lifecycle of their products.
As scientific research continues to evaluate potential associations of MNPs and the chemicals involved in their production with a range of disease outcomes, organizations face a heightened risk of environmental, property damage, and product liability claims.
HETI Technical Services
HETI has experienced professionals, assisting clients with environmental health & safety (EHS) support to help reduce risk exposures and costs. Our scientists, engineers, and other technical staff, with expertise in many different market sectors – including chemical, construction, manufacturing, mining, agriculture, retail, real estate, waste management, oil and gas, and transportation – are available for technical reviews, site assessments, and other EHS services.
HETI is also available to assist with loss control program review, engineering guideline development, market sector risk assessment, and other loss control services to help our clients reduce the possibility and severity of losses before they occur.
To learn more about HETI’s EHS And loss control services, please contact us.
Michael McClure, MS, CIH Senior Scientist