May 15, 2024
In this issue of Trends, we provide several articles on emerging issues in toxicology.
Articles include:
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
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.
Ari Lewis Invited to Serve on the US EPA Science Advisory Board Environmental Justice Science & Analysis Review Panel
The United States Environmental Protection Agency (US EPA) recently announced appointments to its Science Advisory Board (SAB) Environmental Justice Science & Analysis Review Panel (EJSARP). The SAB EJSARP will review the US EPA’s revised Technical Guidance for Assessing Environmental Justice in Regulatory Analysis (EJTG) and develop a self-initiated commentary outlining recommendations on advancing environmental justice science in rulemaking. The EJTG provides broad guidance on how to assess adverse human health and environmental impacts of proposed rules on vulnerable and overburdened populations. Gradient scientist Ari Lewis, M.S., was selected to serve as one of 21 SAB EJSARP panel members.
See a list of the SAB EJSARP members here.
US EPA established the SAB in 1978 under the Environmental Research, Development, and Demonstration Authorization Act (ERDDAA). The SAB is tasked with reviewing “the quality and relevance of the scientific and technical information being used by the EPA or proposed as the basis for Agency regulations.” Members of SAB advisory panels are recognized leaders in their chosen fields with a demonstrated ability to examine and analyze environmental issues with objectivity and integrity.
Ari Lewis is a principal with expertise in toxicology and risk assessment. She has applied her toxicology expertise across a wide range of chemical stewardship issues and is especially interested in environmental justice and cumulative risk assessment, which includes the consideration of risk from non-chemical stressors (i.e., social factors) in vulnerable populations.
Please join us in congratulating Ari Lewis on this noteworthy service appointment!
Gradient’s recently published paper quantifies the potential impact of recall bias in talc and ovarian cancer epidemiology studies.
Recall bias is a familiar concept to epidemiologists. In case-control studies, people with (cases) and without (controls) a health condition are compared with respect to a potential risk factor. In these studies, recall bias can occur when cases and controls remember exposures, events, or experiences from the past differently. Recall bias can result in over- or underestimates of the true risk, though this bias is rarely quantified. The quantification of the potential impact of biases, including recall bias, in epidemiology studies has been getting more attention recently, and Gradient scientists conducted a case study in which they quantified recall bias; this case study is the subject of a newly published paper.
In this new study, the potential impact of recall bias on the results reported in case-control studies was evaluated in a quantitative recall bias analysis examining the relationship between talc exposure and ovarian cancer. Unlike cohort studies of talc exposure and ovarian cancer, which report no overall association, case-control studies have consistently observed small increased risks. Gradient used recently published data on the recall of talc use from the Sister Study, a National Institutes of Health (NIH) study of women with sisters with breast cancer, combined with data from the largest and most recent case-control study of talc and ovarian cancer, to simulate the impact of differential misclassification of talc-use recall on estimated risk estimates. They found that even a modest degree of recall bias could change the statistical significance of risk estimates. This work demonstrates how quantitative bias analyses can contribute to our understanding of disease risks.
Link to the article: “Quantitative recall bias analysis of the talc and ovarian cancer association”
If you have any questions about this analysis, or its implications, please visit our website or contact:
Denali Boon, Ph.D., M.P.H.
Senior Epidemiologist
Julie Goodman, Ph.D., DABT, FACE, ATS
Principal
US EPA lowered the guidance levels for lead in residential soil at CERCLA sites and RCRA Corrective Action facilities from 400 parts per million (ppm) to 200 ppm, or 100 ppm in areas with multiple sources of lead exposure.
On January 17, 2024, the US Environmental Protection Agency (US EPA) lowered the regional screening level (RSL) and regional removal management level (RML) for lead-contaminated soil in residential areas from 400 ppm to 200 ppm. Furthermore, US EPA proposed an RSL of 100 ppm in residential areas with additional sources of lead exposure, including lead water service lines, lead-based paint, and non-attainment areas where air lead concentrations exceed National Ambient Air Quality Standards (NAAQS). This updated guidance applies to Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) sites (more commonly known as “Superfund” sites) and Resource Conservation and Recovery Act (RCRA) Corrective Action facilities.
The previous RSL of 400 ppm in residential areas, which was in effect for more than three decades, was based on a target blood lead level (BLL) of 10 μg/dL in children. To derive the revised lead soil guidance levels of 200 and 100 ppm, US EPA used a target BLL of 5 μg/dL and 3.5 μg/dL in children, respectively. A BLL of 5 μg/dL was the Centers for Disease Control and Prevention (CDC) blood lead reference value (BLRV) until 2021, at which time the BLRV was updated to 3.5 μg/dL. The current BLRV of 3.5 μg/dL means that the CDC estimates that 97.5% of US children aged 1 to 5 years have BLLs at or below 3.5 μg/dL. The CDC has stated that the BLRV is neither a health-based toxicity value nor a regulatory standard.
The updated soil lead guidance applies to all residential sites subject to CERCLA response and RCRA Corrective Action authorities, including sites previously addressed and/or deleted from the National Priorities List. Because a substantial number of properties are expected to undergo evaluation due to this updated guidance, US EPA does not expect all regions to be able to address all properties immediately. US EPA regions will continue to use the existing prioritization process to determine what sites will be evaluated and remediated.
US EPA noted that screening levels are not cleanup standards, and the impact of lower screening levels will depend on how this guidance is applied in specific states. Indeed, US EPA states in its guidance, “While this update will help EPA site teams make site-specific cleanup decisions to protect nearby communities, EPA makes cleanup decisions specific to each site, using site-specific factors, including risk factors and community input that can vary from site to site.” US EPA cautioned, however, that cleanup levels for lead-contaminated sites should not be set at values below natural background levels of lead in soil. According to US EPA, urban background soil lead concentrations can be as high as 2,500 ppm but vary greatly across cities.
For more information, refer to US EPA’s website and/or contact Gradient.
Steven R. Boomhower, Ph.D.
Senior Toxicologist
Kyle J. Colonna, Ph.D., M.P.H.
Epidemiologist
Rosemary L. Mattuck, M.S.
Senior Environmental Engineer
Gradient Receives Risk Assessment Specialty Section Award at the 2024 Society of Toxicology Annual Meeting
Gradient poster received the Risk Assessment Specialty Section Award at the Society of Toxicology 63rd Annual Meeting and ToxExpo
The Society of Toxicology (SOT) Risk Assessment Specialty Section has given an award to a poster authored by Gradient as part of the SOT 2024 Annual Meeting. The winning poster, “Evaluating the Potential for Reproductive Effects from Intermittent Lead Exposures Using Blood Lead Modeling Under Proposition 65,” was authored by Gradient scientists Steven Boomhower, Jiayang Chien, Rosemary Mattuck, and Barbara Beck. The poster was presented at SOT’s 63rd Annual Meeting and ToxExpo in Salt Lake City, Utah, earlier this week.
SOT has 29 Specialty Sections that “may propose sessions for the Annual Meeting, exchange information via newsletters, present awards, and participate in other scientific activities.” In particular, the Risk Assessment Specialty Section “provides opportunities for enhancing knowledge and recognition of current issues, challenges and tools for risk assessment, as well as facilitating discussions to advance the science of risk assessment.”
See a list of Gradient’s SOT posters and presentations here.
Gradient is an environmental and risk sciences consulting firm renowned for scientific excellence. We utilize scientific principles and a systematic study of the data, along with an independent perspective, to help our clients understand their issues. Since 1985, we have delivered work products that are responsive and protective, with the highest professional standards.
The SOT Weekly Update published an essay written by Barbara Beck titled, “My Circuitous Scientific Path through Academic, Industry, and Consulting” as part of a “series designed to celebrate SOT member diversity and showcase the diverse pathways and experiences of its members.”
The essay starts with, “I have a confession regarding my scientific and career journey to toxicology.” Read the essay.