Superfund Research Program
Research Supported by NIEHS Informs Policy and Regulatory Discussion
NIEHS-funded researchers found themselves, this winter, at center stage in the national discussion concerning policy and regulatory issues related to environmental public health.
In an article released Dec. 24, 2013, underscoring the long-term effects of environmental exposure on major public health problems, former New Jersey Governor Christine Todd Whitman (1994-2001) pointed to three large-scale studies, two of them led by NIEHS in-house scientists and grantees. Whitman’s editorial, “Assessing the long-term costs of ignoring the environment,” appeared in NJ Spotlight, an online news service that features insights and information on issues critical to New Jersey.
A Dec. 16, 2013, New York Times feature story, “F.D.A. questions safety of antibacterial soaps,” looked behind the scenes of the new U.S. Food and Drug Administration (FDA) requirement that manufacturers demonstrate the safety of antimicrobial soaps, citing research by scientists supported by the NIEHS Superfund Research Program (SRP).
The story included an interview with SRP grantee Rolf Halden, Ph.D., director of the Center for Environmental Security at Arizona State University. Along with SRP grantees Bruce Hammock, Ph.D., and Isaac Pessah, Ph.D., of the University of California, Davis, and Robert Tukey, Ph.D., of the University of California, San Diego, Halden is one of several NIEHS-funded scientists who have conducted interdisciplinary studies on the extent of environmental pollution by the antimicrobials triclosan and tricloban, and their potential effects on human health.
To read more about the FDA decision and SRP research, visit the NIEHS Environmental Factor website.
High-throughput Screening Examines Multiple Effects of 1060 Compounds on Zebrafish
An investigation led by Oregon State University Superfund Research Program grantee Robert Tanguay, Ph.D., used high-throughput screening to analyze 1,060 unique compounds for 22 possible effects on zebrafish embryos.
Researchers said this is one of the largest systematic in vivo toxicological studies to date. The model system, zebrafish, can be used to test a large number of chemicals with known structures to look at a large number of biological effects, which can allow for the ability to identify groups of chemicals that may share the same mechanism of toxicity.
Those chemicals that show a response in zebrafish can then be verified and further studied using other systems, such as cell-based testing.
“Our study demonstrates that it is now possible to rapidly evaluate the bioactivity of a large number of chemicals in the whole animal,” said Tanguay. “The ability to screen more of the chemical space will help the field move closer to relevant whole animal chemical structure-response relationships for predictive toxicology.”
A comprehensive screening approach
Using their new approach, the researchers conducted developmental and neurotoxicity screening of 1,060 unique ToxCast chemicals. The U.S. Environmental Protection Agency (EPA) National Center for Computational Toxicology Toxcast program is assessing a large number of chemicals, using a diverse set of in vitro tests, with the goal of developing cost-effective ways to prioritize the thousands of chemicals for which there is no toxicity information.
Of the 1,060 unique chemicals evaluated, 487 showed significant biological responses. The scientists continue to refine their experimental approach and to expand the number of chemicals tested. They are working with the EPA, the National Toxicology Program, and others to compare their zebrafish findings with data collected from mammalian cells and whole animal models. The results will allow them to determine the chemical classes for which the zebrafish model is predictive, and to identify the limitations of the model.
The highly automated and streamlined screening approach developed by the researchers is detailed in a paper published in the January issue of Toxicological Sciences. Visit the NIEHS Environmental Factor website for more on the screening approach.
Smith Wins 2014 Alexander Hollaender Award for Environmental Exposure Research
Martyn Smith, Ph.D., professor of toxicology and Director of the University of California (UC) Berkeley Superfund Research Program, was awarded the 2014 Alexander Hollaender Award by the Environmental Mutagenesis and Genomics Society (EMGS) for his contributions to the field of environmental toxicology. The award recognizes outstanding contributions in the application of the principles and techniques of environmental mutagenesis and genomics to the protection of human health.
“Given the mission of the EMGS and Dr. Smith’s contributions to understanding the human health risks associated with environmental exposures, it is appropriate that Dr. Smith’s contributions be recognized with the Alexander Hollaender Award,” Ofelia Olivero, Ph.D., president of EMGS, wrote in a statement.
The EMGS is a scientific society whose mission is to foster scientific research and education on the causes and basic mechanisms of DNA damage and repair, mutations to DNA, heritable effects, alterations in genome function, and their relevance to disease. The society also promotes the application and communication of this knowledge to genetic toxicology testing, risk assessment, and regulatory policy-making to protect human health and the environment.
The award will be presented to Smith during the EMGS annual meeting in Orlando, Florida, on September 16, 2014.
Study Identifies Novel Compounds More Mutagenic than Parent PAHs
Researchers at Oregon State University (OSU) have discovered novel breakdown products that form when specific high molecular weight polycyclic aromatic hydrocarbons (PAHs) chemically interact with nitrogen. These nitrated-PAHs (NPAHs), which were not previously known to exist, are more mutagenic than their parent PAH compounds.
Mutagens are physical or chemical agents that change the genetic material of an organism, increasing the frequency of mutations. Because many mutations cause cancer, mutagens are likely to also be carcinogens, or agents directly involved in causing cancer.
“Some of the compounds that we’ve discovered are far more mutagenic than we previously understood and may exist in the environment as a result of heavy air pollution from vehicles or some types of food preparation,” said Staci Simonich, Ph.D. , professor of chemistry and toxicology in the OSU College of Agricultural Sciences and Superfund Research Program (SRP) researcher.
According to the OSU press release , NPAHs raise further concerns about the health impacts of heavily-polluted urban air and dietary exposure, although it has not yet been determined in what level the compounds might be present, and no health standards now exist for the compounds.
The study , led by Simonich, was published in January in the journal Environmental Science and Technology.