Presentations
Download PDFs of the ECEC22 conference presentations.
Keynote Presentations
Abigail Hendershott – Michigan PFAS Action Response Team
Biography: Abigail (Abby) Hendershott, a 30-year veteran of the Michigan Department of Environment, Great Lakes, and Energy (EGLE), is the Executive Director of the Michigan PFAS Action Response Team (MPART). MPART is a multi-agency task force charged with investigating PFAS contamination, overseeing clean-up and other response activities aimed at protecting Michigan’s drinking water.
Ms. Hendershott has focused on PFAS response activities since 2017 and led the team responsible for Michigan’s largest PFAS contamination response to-date, the investigation into the former Wolverine Worldwide tannery in Rockford. In that role, her team was responsible for a $113 million legal settlement establishing clean-up plans and municipal water connections for thousands of residents in northern Kent County.
She supervised the Remediation and Redevelopment Division’s Grand Rapids district office and has more than 25 years of project management experience for complex environmental remediation projects.
Michigan’s Wholistic Approach to PFAS collaboration
Why is it so important to collaborate on PFAS issues? PFAS research, science and public policies represent some of the most complex issues that environmental regulators and scientists have faced in the last 30 years. Michigan’s creation of the Michigan PFAS Action Response Team in 2017 has led to Michigan being leaders in the nation on proactive PFAS investigations, sampling and coordinated public health responses. This team is made up of 7 different agencies within the state of Michigan that diligently work to collaborate on all the complex and interconnected PFAS issues. Ranging from public drinking water, fish sampling, surface water and foam sampling, deer, and mallard sampling to biosolids, groundwater and crop sampling.
Scott Coffin – California State Water Resources Control Board
Biography: Dr. Scott Coffin holds a PhD in environmental toxicology and serves as a Research Scientist at the California State Water Resources Control Board. Since 2014, Dr. Coffin’s research has focused on microplastics toxicity and characterization.
Currently, Dr. Coffin is leading California’s development of drinking water regulations for microplastics and advising management strategies in aquatic ecosystems. Dr. Coffin has recently led international expert groups to assess risks of microplastics to humans and aquatic ecosystems and harmonize analytical methods for microplastics.
Assessing and Managing Risks of Microplastics in Ecosystems and Drinking Water
Concerns regarding widespread contamination of microplastics prompted the California legislature in 2018 to pass legislation aimed at monitoring and managing the human health impacts in drinking water and impacts to coastal ecosystems. These laws (Senate Bills 1422 and 1263) require the State Water Resources Control Board (State Water Board) and the Ocean Protection Council to develop standardized analytical monitoring methods, assess risks to humans and aquatic ecosystems, perform monitoring to determine exposure to humans and contamination in the environment, and recommend policy strategies to reduce further contamination. Fulfilling these policy and regulatory goals requires research to fill scientific gaps in this rapidly emerging field.
To develop standardized analytical methods for monitoring microplastics, the State Water Board collaborated with the Southern California Coastal Water Research Project and 40 laboratories to conduct an inter-laboratory method validation study and determine the strengths and weaknesses of microplastics analytical methods. This study determined that spectroscopic methods including Raman and infrared can provide accurate and precise enumeration of microplastic particle counts in drinking water for particles as small as 20 microns. Standardization of analytical methods is an important first step to reliably monitoring and assessing risks.
While the health impacts of microplastics in aquatic organisms have been relatively well-documented, evidence for impacts to humans are limited and rapidly emerging. We convened an expert workshop to develop frameworks for assessing microplastics’ risks to humans and ecosystems and applied this framework to the available literature. Hazard studies were screened for quality criteria prior to undergoing additional expert evaluation and studies passing minimum criteria were deemed fit-for-purpose.
Of the 29 in vivo mammalian toxicity studies on microplastics, twelve were deemed fit-for-purpose, of which seven reported adverse effects on male and female reproductive systems. Although no single study met all quality criteria necessary for risk assessment, consistent trends were observed between studies, with inflammation and oxidative stress identified as likely mechanisms of toxicity. While we were able to derivate a human health-based threshold for microplastics, the value is highly uncertain due to incomplete exposure information and unknown differences in toxicity between polymers and shapes.
Our expert workshop identified 167 toxicity studies for microplastics in aquatic organisms, of which 21 were deemed fit-for-purpose. Multiple risk-based thresholds were developed that correspond to increasing certainty in adverse ecosystem impacts and suggest increasing levels of response from governments. Comparisons of thresholds to monitoring data in San Francisco Bay suggest early signs of ecosystem impairment with a moderate degree of certainty.
Informed by the State Water Board’s findings of contamination and risks of microplastics to humans and ecosystems, the Ocean Protection Council will convene inter-sector workshops with industry, academia, and governments to develop strategies to address plastic pollution along their entire lifecycle. A range of policy interventions will be considered, from upstream solutions such as reduction mandates and product re-design, to downstream solutions such as capture and treatment in significant contamination and exposure pathways.