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ATSDR Studies How Chemicals Affect Our Health

Did you know that more than 80,000 chemicals are registered for use in the United States? Chemicals make our lives easier and are included in everyday items like foods, personal care products, prescription drugs, household cleaners, and lawn care products. However, we do not know the effects of many of these chemicals on our health. Though relatively few chemicals are thought to pose a major risk to human health, we may be exposed to chemicals when they become pollutants in our air, water, or soil. The Agency for Toxic Substances and Disease Registry (ATSDR) works to protect public health by understanding a chemical's toxicology. In other words, ATSDR identifies both the effects of these chemicals and at what levels of exposure they may become hazardous to humans.

Computational Toxicology is helping ATSDR scientists to get a better understanding of the public health impacts of exposure to chemicals for which little or no information is available. By using a scientifically credible, timely, and less expensive alternative to traditional toxicology testing, scientists learn important information about a chemical's health impact. ATSDR relies on the latest advances in computational toxicology to support its mission to protect the public's health by providing trusted health information to prevent harmful exposures and diseases related to toxic substances. Learn more about how ATSDR is using computational toxicology!

CompTox Lab Services

Photo: Chemical spill.Housed within ATSDR's Division of Toxicology and Environmental Medicine, the Computational Toxicology Laboratory (CompTox Lab) protects public health by developing and applying three state-of-the-art methods to determine and characterize risks from exposure to hazardous substances.

Quantitative structure-activity relationship (QSAR) techniques allow scientists to make scientifically sound estimates about how an unknown substance will interact with the body by looking at similar substances for which much information is already available.

Pharmacokinetic/pharmacodynamic (PBPK) models allow scientists to predict how a substance will interact with the body, especially which areas of the body (brain, liver, etc.) may be affected following exposure to hazardous substances. PBPK modeling is also helpful in predicting if a substance will be absorbed or expelled by the body.

Benchmark dose (BMD) modeling helps scientists determine the safest possible level of exposure for certain chemicals. This is done by identifying health effects of chemicals at doses that have not yet been tested.

ATSDR uses its CompTox Lab in a Variety of Ways

Emergency Response and Bioterrorism

  • After Hurricane Katrina, ATSDR's CompTox Lab used QSAR techniques to assess the dangers of approximately 200 chemicals that people in the affected areas were in danger of encountering in the days following the storm.
  • QSAR techniques are being done on a group of chemicals from the CDC/ATSDR Chemical Terrorism List. Early results show that QSAR may be useful for providing limited data for use in acute exposure scenarios for chemical terrorism substances that currently have no available toxicity data.
  • In response to an urgent congressional request for information on the toxicity of one of the chemicals spilled at a chemical factory in New York, QSAR analysis predicted the chemical to be mildly irritating to the skin, but revealed no threat of cancer-causing substances. ATSDR provided these results to the Bureau of Toxic Substance Assessment at the New York State Department of Health (DOH), and follow-up consultations were held shortly after.


  • Based on a QSAR analysis performed by CompTox Lab scientists, the National Toxicology Program (NTP) initiated a study of a drinking water contaminant in the Toms River area of New Jersey.
  • International collaborations with TNO Nutrition and Food Research, Netherlands used PBPK models developed in the ATSDR's CompTox lab to investigate interactions between trichloroethylene, benzene, lead, and methyl mercury.
  • CompTox Lab scientists recently collaborated with researchers at the University of Georgia to develop PBPK models to investigate polychlorinated biphenyls, or PCBs.

Children's Health

Child-based PBPK models for certain substances were developed to determine if younger age groups are more sensitive to chemical exposures than adults. Thus far, results of the modeling efforts show that very young children are more susceptible to chemical toxicity by inhaling or ingesting certain substances than adults exposed to identical environmental conditions.

More Information

  • Page last reviewed: August 9, 2010 (archived document)
  • Content source:
    • Office of the Associate Director for Communication, Digital Media Branch, Division of Public Affairs
    • Page maintained by: Office of the Associate Director for Communication, Digital Media Branch, Division of Public Affairs