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

Gradient will present at the Utility Solid Waste Activities Group (USWAG) 10th Annual CCR Workshop.  June 17-19, 2024. Nashville, TN.

Gradient will present at Battelle’s Chlorinated 2024 Conference.  June 2-6, 2024. Denver, CO.

• “Domestic Wastewater as a Potential Non-Point Source of PFAS Contamination in North America.” Patricia Clyde, Renee Hebert, Kathryn Zic, and James Rice.

The California Department of Toxic Substances Control draft 2024-2026 work plan continues to identify and updates broad product categories the agency will consider for potential Priority Products, and requires manufacturers of Priority Products to conduct alternatives analyses.

At the end of May, the California Department of Toxic Substances Control (DTSC) released a draft 2024-2026 Priority Product Work Plan for the Safer Consumer Products (SCP) program. The SCP program requires manufacturers of listed products (“Priority Products”) to conduct an alternatives analysis to determine whether safer product chemistries or designs are feasible. The draft work plan identifies broad product categories that DTSC will research and consider for potential Priority Products over the next few years. Note that these categories are not Priority Products and do not require any regulatory response until a specific Priority Product is identified and listed formally. Regardless, the draft work plan serves as notice that these product categories are on the DTSC’s radar, and manufacturers of these products are advised to monitor DTSC’s CalSAFER website for developments and opportunities to provide comment prior to product listing. Similarly, manufacturers of these products should review DTSC’s questions on the draft work plan and provide answers, if interested. Seven product categories will be the focus of DTSC’s efforts under the draft work plan, several of which have been carried forward from the 2020-2023 Work Plan. In addition, where work is already underway, DTSC indicates upcoming activities towards product listing. The seven categories are:

• Beauty, Personal Care, and Hygiene Products – DTSC is developing a Priority Product profile to list sodium hydroxide in hair straightening products as a Priority Product.
• Cleaning Products – DTSC plans to release documents in the next few months that will support future rulemaking concerning 1,4-dioxane in personal care and cleaning products. The agency also notes that laundry detergents containing nonylphenol ethoxylates are already in the process for listing as a Priority Product.
• Building Products and Materials Used in Construction and Renovation – Artificial turf and engineered stone are mentioned specifically as topics of interest.
• Children’s Products (two categories) – Phthalates, formaldehyde, styrene, bisphenols, and parabens are noted as chemicals of interest.
• Paints (new, formerly part of building products) – DTSC has created a specific category for paints to highlight its intention to evaluate these products, focusing particularly on per- and polyfluoroalkyl substances (PFAS) and microplastics in paints.
• Products That Contain or Generate Microplastics (new) – DTSC is in the process of adding product(s) that generate microplastics to the Candidate Chemicals list. It is not clear which product(s) DTSC will select; however, the draft work plan mentions potential products such as plastic packaging, synthetic clothing and textiles, cigarette filters, tires, and paints.

In addition, DTSC has indicated that it will begin researching several other product categories as resources allow, including:

• Food packaging;
• Motor vehicle parts, accessories, maintenance, and repair materials;
• Electronics, with a particular interest in PFAS and flame retardants;
• Products used or produced by metal plating and finishing facilities;
• Pet care products; and
• Sporting and athletic equipment.

Further, DTSC notes that in the Motor Vehicle Parts category, the designation of motor vehicle tires containing zinc as a Priority Product is expected to start in 2024. DTSC has already designated motor vehicle tires containing the antiozonant 6PPD as a Priority Product and it is unclear how these two efforts will interact.

Moreover, two notable changes in the SCP program are mentioned briefly in the draft work plan:

• California’s Senate Bill (SB) 502 provided DTSC enhanced authority to require manufacturers to submit available data on product chemical composition, consumer use, and sales. Failure to do so can result in administrative or civil penalties.
• Under SB 502, DTSC also was given the authority to move directly to regulatory response instead of requiring manufacturers to conduct an alternative analysis. In this case, DTSC will use publicly available studies or existing evaluations of alternatives. How DTSC will assess whether existing analyses meet all the requirements of the regulation remains to be seen.

Regarding the draft work plan, rather than accepting general comments, DTSC has developed nine specific questions to which experts and members of the public are invited to submit answers by July 1, 2024, via CalSAFER. In addition, DTSC will be hosting a virtual workshop to review the draft work plan and receive comments on June 18, 2024.

A copy of the draft three-year work plan is available here. If you have any questions, please contact:

Tom Lewandowski, Ph.D., DABT, ERT, ATS
Principal
tlewandowski@gradientcorp.com

Jiaru Zhang, M.P.H., DABT
Principal Scientist
jzhang@gradientcorp.com

Gradient Hosting Webinar on ISO 18562:2024 – Chemical and Toxicological Strategies

Webinar Date:  Tuesday, June 25 • 1:00-2:00 PM (EST)

Register here

Join Gradient biocompatibility experts, Drs. Alex Gauthier and Rachel Chang, and special guest speaker Corey Campbell, from Legend Technical Services, Inc., in a free webinar that will provide an “Overview of ISO 18562:2024 – Chemical and Toxicological Strategies.”  Recent updates to the ISO 18562 series of standards introduce major changes to the chemical, biological, and toxicological evaluation of gas pathway devices (e.g., ventilators, anesthesia workstations, breathing systems).  This webinar will provide insights on key ISO 18562-1, -2, -3, and -4 standards and their resulting impacts on biocompatibility and related testing strategies.  Topics include:

• Preparing biological evaluation plans and reports for gas pathway medical devices;
• Designing testing strategies for evaluating potential patient exposures to particulate matter (ISO 18562-2), volatile organic substances (ISO 18562-3), and leachables in condensate (ISO 18562-4); and
• Conducting toxicological risk assessment of extractables and leachables, and assessment of particulate matter and volatile gas substances.

Alex G. Gauthier, Ph.D., is a Senior Toxicologist at Gradient who specializes in medical device biocompatibility, toxicological risk assessment, pharmaceutical non-clinical safety assessment, and large animal safety and efficacy studies.

Rachel Chang, Ph.D., DABT, is a Senior Toxicologist at Gradient with expertise in human health risk assessment and developmental toxicology.  She focuses primarily on toxicological risk assessment of extractables and leachables from medical devices, safety assessments of consumer products, and benchmark dose modeling.

Corey Campbell, CHMM, is an Industrial Hygienist at Legend Technical Services, Inc., who conducts design/set-up and testing of medical devices for any contribution of volatile organic compounds, PM_2.5/PM₁₀ particulate, and inorganic gases (carbon dioxide, carbon monoxide and ozone).

Register here

May 15, 2024

In this issue of Trends, we provide several articles on emerging issues in toxicology.

Articles include:

• Artificial Intelligence and Toxicology
• Evolving Chemical Risk Evaluation and Management Under the Toxic Substances Control Act:  Trichloroethylene as an Example
• Potential Health Effects of Plastic Additives
• Gradient Joins Geosyntec Consultants, Expanding Client Service for Health and the Environment
• What’s New at Gradient

Gradient Presenting at World of Coal Ash (WOCA), May 13-16, 2024

”Evaluating Surface Impoundment Closure Alternatives Using Relative Impact Assessment – Two Case Study Examples”
Gradient Authors: Andrew Bittner and Qian Zhang

”Corrective Action Sustainability: Holistic Decision Support Tool”
Gradient Authors: John Kondziolka, Ari Lewis, and Andrew Bittner

Congratulations to Egidio Tentori!

Environmental Business Council New England (EBC) has announced Egidio F. Tentori, Ph.D., E.I.T. – Senior Environmental Engineer with Gradient has joined the Leadership Team as an Ascending Professional Representative. In this role, Egidio will provide the Working Group with insight into EBC’s Ascending Professionals community and Committee, as well as thought leadership on the Emerging Contaminants industry.

Learn more here: https://lnkd.in/eeB-wMGy

https://lnkd.in/guknDnz9

Gradient will be presenting “A Refined Read-Across Approach to Support Environmental Assessment of Data-Poor Pharmaceuticals” at SETAC Europe 34th Annual Meeting during May 5-9, 2024 in Seville, Spain.  Authors include:  Ifeoluwa A. Bamgbose, M.S., DABT, Janet Vo, and Tim Verslycke, Ph.D.

Dr. Julie Goodman has been elected to the Academy of Toxicological Sciences (ATS) Board of Directors.

The Academy of Toxicological Sciences (ATS) is a nonprofit organization that exists to certify toxicologists who are recognized by their peers for their expertise and sound scientific judgment.  The purpose of this recognition and certification is to ensure, through peer review of credentials, the competence and experience of professionals whose work affects public welfare.  Candidates for certification must have demonstrated evidence of knowledge of toxicology and active involvement in toxicological activities.  A Fellow of the Academy must have an exemplary record of professional accomplishment, as well as extensive evidence of recognition by peers of competency and sound scientific judgment in toxicology as reflected by appointment or election to councils, committees, etc.