July 25, 2024
Studies Evaluate “Real-Life” Exposures to Micro- and Nanoplastics (MNPs) Associated with Consumer Products
Micro- and nanoplastics (MNPs), i.e., plastic particles less than 5 millimeters and 1 micrometer in size, respectively, are ubiquitous in the environment and can be added intentionally to, or generated inadvertently by, a broad range of consumer products. In a June webinar, the European Commission-funded Research Cluster to Understand the Health Impacts of Micro- and Nanoplastics (CUSP) presented initial findings from two of its ongoing research projects: 1) the POLYRISK project and 2) the “Actionable eUropean ROadmap for early-life health Risk Assessment of micro- and nanoplastics” (AURORA) project. These studies are notable because they are some of the first to measure “real-life” consumer, environmental, and occupational exposures to MNPs in humans and evaluate potential health outcomes.
The POLYRISK project is evaluating effects on the immune system (e.g., inflammation) associated with MNPs as part of five “real-life” exposures:
1. Volunteers exposed for four hours at a busy road, an urban park, or a crossroad;
2. Workers in a textile factory;
3. Workers in a tire refurbishment factory;
4. Volunteers playing indoor soccer on artificial turf with or without rubber granulates; and
5. Eight different brands of bottled drinking water for sale in Norway.
According to the lead researcher of the POLYRISK project, Dr Hubert Dirven, the bottled drinking water study was terminated because the detected levels of MNPs greater than 1 micrometer in size were “so low that we thought it would not make any sense to do the study.” For the other POLYRISK studies, measurement of MNP levels in air samples and blood samples of volunteers is ongoing, as well as evaluation of markers of immune function in blood. The POLYRISK project will be completed in 2025.
The AURORA project focuses on early-life exposures to MNPs and associated effects on fetal growth and health outcomes in children. The researchers are analyzing MNP levels in over 800 historical samples of placenta and cord blood collected from subjects in a birth cohort in Spain. The study is also assessing placental function (i.e., placental blood flow) and molecular markers of inflammation, antioxidant response, and endocrine function. Since the enrolled children are now 12 years old, the researchers are evaluating child health outcomes. The researchers hope to complete collection of exposure data in 2024, and complete the project in 2026.
Overall, the CUSP research efforts seek to advance the understanding of potential effects associated with MNPs on human health, and develop a framework for risk assessment of MNPs. As noted by CUSP in its policy brief published in April 2024, MNPs are “a reasonable concern” for public health; however, “the health risks remain unclear and the hazards, exposures and risks of individual types of plastics and their specific chemical additives still need to be determined.”
The CUSP webinar recording and presentation slides are available here. If you have any questions, please contact:
Andrew Yeh, Ph.D., DABT
Senior Toxicologist
Jiaru Zhang, M.P.H., DABT
Principal Scientist/Toxicologist
Matt Tymchak, M.S.
Senior Hydrologist