Superfund Research Program
October 19, 2012
November 5, 2012
April 15, 2013
This webinar series coincides with the Superfund Research Program's 25th Anniversary and the 10th Anniversary of the Superfund Research Program (SRP) Risk e-Learning webinars. The SRP chose this opportunity to highlight the Program's accomplishments in the area of arsenic research. Since its inception, the SRP has funded work to understand the consequences of exposure to arsenic at the molecular and population levels. Equally important, these researchers have developed unique and effective methods to detect arsenic in the environment and to minimize human exposure to arsenic from drinking water and food sources.
Session I - Emerging Issues – Arsenic Exposures
October 19, 2012, 2:00 p.m. - 4:00 p.m. EDT
An archive of this webinar is available on the U.S. Environmental Protection Agency’s (EPA) Clu-in Training & Events Webpage
- Introduction by William Suk, Ph.D., director, Superfund Research Program
- Moderator/presenter: Joseph H. Graziano , Ph.D., program director Columbia University SRP Center
- Presenter: Margaret Karagas , Ph.D., Dartmouth College SRP Center
- Presentation title: Epidemiologic approaches to tracking human health effects of low-level arsenic exposure
- Presenter: A. Eduardo Saez , Ph.D., University of Arizona SRP Center
- Presentation title: Atmospheric transport of metal and metalloid contaminants by atmospheric dust and aerosol from mining operations.
In this session Joseph Graziano, Ph.D., presented a historical overview of the global human health issues related to drinking water. His presentation focused on the sources and prevalence of arsenic exposures and the evolution of our understanding of the spectrum of human health impacts and how arsenic imparts negative effects. Margaret Karagas, Ph.D., gave a brief overview of her epidemiology work that focuses on etiologic mechanisms and prevention of human cancers and other adverse health outcomes. She discussed recent findings from studies to develop biomarkers of arsenic exposure and susceptibility in a U.S. population that relies heavily on private drinking water systems where over 10% of the wells contain low to moderate levels of arsenic. She also presented information from her research, from her early studies investigating cancer risk to her more recent investigation into sources of arsenic exposure among pregnant women, e.g., via their consumption of rice and tap water, and the research translation activities that help raise awareness of the presence of arsenic in the drinking water supply. A. Eduardo Saez, Ph.D., focused on his and Co-PI’s (Eric Betterton, Ph.D.) latest research that involves the characterization of windblown dust from mine tailings and also touched on the University of Arizona SRP’s phytostabilization field study in the southwestern United States that uses native plants to successfully reduce the amount of dust coming off the tailings, thereby reducing potential aerial exposures.
Session II - Emerging Issues in Arsenic Exposure and Disease
November 5, 2012, 2:00 p.m. - 4:00 p.m. EST
An archive of this webinar is available on the EPA’s Clu-in Training & Events Web page.
- Moderator: Reeder Sams, Acting Deputy Director, National Center for Environmental Assessment, US EPA
- Presenter: Allan Smith, M.D., Ph.D., University of California, Berkeley
- Presentation title: The Astonishing Long-Term Effects of In Utero & Early Childhood Exposure to Arsenic
- Presenter: Josh Hamilton , Ph.D., Marine Biological Laboratory
- Presentation title: Mouse Models of Human In Utero and Adult Exposures to Low-Dose Arsenic in Drinking Water
In this session SRP researcher Allan Smith, M.D., Ph.D., discussed a unique arsenic exposure scenario that provides a rare opportunity to investigate the long-term mortality impact of early-life arsenic exposure. Smith’s research team explored the mortality rates in Antofagasta, Chile, which had a distinct period of very high arsenic exposure from 1958 to 1971 when an arsenic removal plant was installed. The research team compared mortality rates in Antofagasta in the period of 1989-2000 with those of the rest of Chile, focusing on subjects who were born during or just before the peak exposure period and who were 30-49 years of age at the time of death. The results of Smith’s research suggest that exposure to arsenic in drinking water during early childhood or in utero has major effects on subsequent mortality in young adults from both malignant (laryngeal cancer, lung cancer, and bladder cancer) and nonmalignant (acute myocardial infarction, chronic renal failure, and bronchiectasis) causes of death, beyond the effects attributable to any other human environmental exposure.
SRP researcher Josh Hamilton, Ph.D., discussed his recent research to develop unique mouse models of human fetal and early childhood exposure to arsenic (As) in order to determine both the adverse consequences of these exposures in controlled laboratory experiments and to investigate the underlying mechanisms for these effects. Hamilton presented the results of two mouse models. In the first model, young adult male and female C57BL6 mice were exposed to inorganic As+3 in drinking water at 10 or 100 parts per billion (ppb) – 10 ppb is the current U.S. EPA Maximum Contaminant Level (MCL) and 100 ppb is twice the previous MCL of 50 ppb. These experiments revealed profound effects on innate immune response of the lung to a viral (influenza) infection and on metabolic regulation by liver and adipose tissue. In the second model young adult female mice were exposed to 10 ppb As in drinking water during pregnancy and post-natal nursing, and effects were observed on the mothers and the offspring. This latter model was designed to mimic recent human epidemiology studies from Chile that investigated the long-term consequences of fetal and early childhood exposures to As in drinking water. The results of these mouse experiments demonstrated profound effects on metabolic regulation by the mothers and on growth and development by the offspring. These results support the hypothesis that exposure to As at very low levels equivalent to the U.S. MCL, particularly during pregnancy and during critical windows of fetal and neonatal development, can induce a number of adverse effects both in the adult mothers and their offspring, suggesting that such effects may occur in humans and may contribute to increased disease risks in exposed populations.
Session III - Arsenic – Interventions
April 15, 2013, 12:00 p.m. – 2:00 p.m. EDT
An archive of this webinar is available on the EPA's Clu-in Training & Events webpage.
- Moderator William Suk, Ph.D., director, Superfund Research Program
- Presenter: Joseph Calo , Ph.D., Brown University
- Presentation title: "Zero-valent Iron (ZVI) Removal of Arsenic in a Spouted Vessel"
- Presenter: Girish Srinivas , Ph.D., TDA Research, Inc.
- Presentation title: "System for Decontaminating Well Water for Drinking"
In the first presentation SRP Researcher Joseph Calo, Ph.D., will discuss his team’s latest research on developing a spouted vessel/fixed bed filter system for the removal of arsenic from water. The system uses zero-valent iron (ZVI) particles circulating in a spouted vessel that continuously generates active colloidal iron corrosion products. These corrosion products are generated by the "self-polishing" action between ZVI source particles rolling in the moving bed that forms on the conical bottom of the spouted vessel. This action also serves as a "surface renewal" mechanism for the particles and provides for maximum ZVI material utilization. The colloidal material produced in this fashion is continuously captured and concentrated in an internal fixed bed filter where arsenic complexation occurs. This system has been shown to reduce 100 µg/L of arsenic to below detectable levels in less than an hour. Calo’s presentation will focus on the spouted vessel/fixed bed filter system for removing arsenic from water, and he will share his most recent research results.
In the second presentation SRP Researcher Girish Srinivas, Ph.D., will discuss research being conducted by TDA Research, Inc. (TDA) to develop a cost effective, simple point-of-use (POU) water purifier. The purifier is based on capacitive deionization (CDI) for removing problematic toxic ionic contaminants from well water not attached to a large public water works. TDA’s CDI technology can effectively remove perchlorate, nitrate, arsenic, lead, and other harmful inorganic ions from well water to meet EPA drinking water specifications in a simple, DC powered device. The technology can be used for POU applications (e.g. under the sink) in homes that use well water or in developing countries at well sites, where, if power is unavailable, it can be operated using a simple photovoltaic system.
Individuals with disabilities who need accommodation to participate in this event should contact Heather Henry (email@example.com, 919 541-5330). TTY users should contact the Federal TTY Relay Service at 800-877-8339. Requests should be made at least 5 business days in advance of the event.