EPA Partners with Unilever to Advance Chemical Screening
Published March 13, 2018
EPA, along with other Federal Agencies, State Environmental and Health Agencies, International Governmental Agencies and Industry groups, evaluates chemicals for potential health effects in an effort to protect people and the environment from unintended consequences of chemical use.
EPA’s Computational Toxicology (CompTox) researchers are developing and using new approaches to evaluate the potential health effects of chemicals. These approaches use laboratory technologies such as robotics, microfluidics, molecular biology and microscopy to evaluate chemical effects on human cells in rapid and efficient manner. Computational modeling is then used to analyze the data and integrate the information to predict potential health effects.
As part of this effort, EPA is collaborating with Unilever, a global consumer products company, to determine if these new approaches can be used to assess the risk of chemicals in consumer products. To make this determination, EPA and Unilever have identified case study chemicals and are using these new approaches to generate data for use in prototype risk assessments. The case study chemicals are common natural ingredients found in consumer products.
While EPA is providing expertise for development of assays and data generation for these chemicals, Unilever is providing exposure information from use of consumer products to help estimate exposures. EPA and Unilever are combining this information on each chemical to estimate the potential health risks. The approaches and tools being used for the prototype risk assessments are:
- Toxicity Forecaster: ToxCast screens chemicals using targeted chemical screening technologies (high-throughput screening). Living cells or isolated proteins are exposed to the case study chemicals. Readouts from these screens can identify potential biological changes that may suggest potential toxic effects.
- High-throughput Transcriptomics: Researchers are using automated chemical screening technology (high-throughput screening) to determine how the case study chemicals affect the expression of different genes inside cells. Based on how the chemicals affect gene expression, computational tools are used to identify the mechanism by which the chemical may cause toxicity.
- CompTox Chemistry Dashboard: This is a publicly available online tool which provides access to a variety of information on over 700,000 chemicals currently in use including the case study chemicals. The dashboard is a gateway to an array of related public domain databases.
- Read-Across: When performing a risk assessment on a new ingredient in a product, data gaps are common. In these cases, read-across approaches may be used. Read-Across identifies similar chemicals that have existing toxicological information and the data from these chemicals are used to inform the potential toxicity of the ingredients that lack data.
- Incorporating Metabolism into High-throughput Screening: Many automated chemical screening (high-throughput screening) technologies lack human relevant chemical metabolism. As a result, they may miss chemicals that are metabolized to a more toxic form. EPA and Unilever are attempting to retrofit these technologies to incorporate processes that reflect how chemicals metabolized in the body.
- Estimating Dose: Biologically effective doses can be estimated for the automated chemical screening technologies using computational modeling and measuring a few key parameters. The parameters include how much of chemical binds to proteins in the blood and how quickly the chemical is broken down by cells in the liver called hepatocytes. The computational modeling allows the results of the automated screening to be linked to a human equivalent dose in a typical consumer product exposure scenario.
This collaboration has the potential to provide better ways to evaluate the potential health effects of new ingredients and chemicals. These methods could be used by both industry and governmental agencies to reduce the costs associated with safety testing and ultimately address the thousands of untested chemicals in our environment.