Milken Institute School of Public Health Poster Presentations (Marvin Center & Video)
Predicting Long Term Risk Values from Short Term Chemical Exposure Tests
Poster Number
36
Document Type
Poster
Publication Date
3-2016
Abstract
Environmental and public health organizations including the World Health Organization (WHO) and the U.S. Environmental Protection Agency (USEPA) develop human health reference values (HHRVs) that set ‘safe’ levels of exposure to non-carcinogens. This research investigates whether the results of short-term animal studies can reasonably provide a quantitative estimate of a long term point-of-departure (POD) allowing faster development of chronic HHRVs. Currently the development of HHRVs can be slow and cumbersome, leaving chemicals unanalyzed and in the environment. The goal is a methodology to predict the doses associated with the long-term health effects of chemicals that have short-term data but do not have long-term data. Data from the National Toxicology Program’s (NTP) technical reports have been extracted and used to compare best fits for points of departure (PODs) for 41 chemicals tested both long-term and short-term between 2000 and 2012. The analysis focuses on non-neoplastic lesions, final mean body weight and mean organ weight. Using these data, statistical modeling techniques are being performed to determine the predictability of short-term data in determining long-term PODs. Comparisons will be made by chemical, within specific test animal groups (e.g., female mice) and by lesion site or type. The results are hypothesized to be models for estimation of long-term PODs from short-term data and an estimation of uncertainty in these relationships. Preliminary data suggest there are quantitative relationships between exposures causing non-neoplastic effects in short-term tests and those causing effects in long-term toxicity tests.
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Open Access
1
Predicting Long Term Risk Values from Short Term Chemical Exposure Tests
Environmental and public health organizations including the World Health Organization (WHO) and the U.S. Environmental Protection Agency (USEPA) develop human health reference values (HHRVs) that set ‘safe’ levels of exposure to non-carcinogens. This research investigates whether the results of short-term animal studies can reasonably provide a quantitative estimate of a long term point-of-departure (POD) allowing faster development of chronic HHRVs. Currently the development of HHRVs can be slow and cumbersome, leaving chemicals unanalyzed and in the environment. The goal is a methodology to predict the doses associated with the long-term health effects of chemicals that have short-term data but do not have long-term data. Data from the National Toxicology Program’s (NTP) technical reports have been extracted and used to compare best fits for points of departure (PODs) for 41 chemicals tested both long-term and short-term between 2000 and 2012. The analysis focuses on non-neoplastic lesions, final mean body weight and mean organ weight. Using these data, statistical modeling techniques are being performed to determine the predictability of short-term data in determining long-term PODs. Comparisons will be made by chemical, within specific test animal groups (e.g., female mice) and by lesion site or type. The results are hypothesized to be models for estimation of long-term PODs from short-term data and an estimation of uncertainty in these relationships. Preliminary data suggest there are quantitative relationships between exposures causing non-neoplastic effects in short-term tests and those causing effects in long-term toxicity tests.
Comments
Presented at: GW Research Days 2016