Here is an investigator, named Hazel, at a hazardous waste site. There has been a spill of something and it may be dangerous. What is it? Has anyone been harmed? Do people need to be evacuated? These are just some of the questions scientists at CDC and at our sister agency, the Agency for Toxic Substances and Disease Registry, face when they are called in to help. And for some fun brainteasers, riddles, jokes, and games from the National Institute of Environmental Health Sciences, click here.

Click on areas in the photo to learn more about hazardous waste sites.

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