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Providing Practical Information on Chemical Hazards

Background and Purpose

HESIS staff member providing telephone advice

Information on the health hazards of chemicals is often published in scientific journals and technical documents that can be difficult to find and hard to understand. Although chemical manufacturers and distributors are required to include health hazard information on Material Safety Data Sheets, the information is often written in technical language and can be incomplete and inaccurate, especially for cancer, reproductive damage and other long-term effects.

The Hazard Evaluation System and Informaton Service (HESIS) was established to ensure that workers and employers have access to practical information on chemical hazards to help them prevent work-related illness and disease.  Over the years, HESIS has gained unique experience in evaluating complex, technical information on chemical hazards, determining what it means for people in real work situations, and communicating the health hazard in practical language.  This unique experience comes from answering questions and responding to concerns about workplace chemical exposures from all sectors that care about protecting worker health, including workers, employers, unions, government agencies and health care providers.

HESIS makes complex, technical information about chemical hazards available and more readily understood to help workers and employers protect against chemical exposures in the workplace.  The ultimate goals are more effective prevention efforts and better recognition and treatment of work-related illness.

Photo: HESIS staff member providing telephone advice


  • Review and evaluate scientific literature to determine the potential impact of toxic chemicals on workers’ health;
  • Identify workplace chemicals that pose health hazards risks for California workers;
  • Research and identify safer substitutes for hazardous chemicals;
  • Develop and disseminate educational publications on chemical hazards and other topics that impact large numbers of workers;
  • Respond to questions about workplace hazards from workers, employers, government agencies, and health care providers through our statewide telephone information line.
Related Health Information
Program Information
Last modified on: 8/5/2013 12:36 PM