Which agency is responsible for environmental policies and regulations concerning hazardous materials?

The Environmental Protection Agency (EPA) is the agency responsible for establishing and enforcing environmental policies and regulations related to hazardous materials. The EPA's primary mission is to protect human health and the environment by regulating the management, disposal, and cleanup of hazardous substances. This includes overseeing the safe handling of hazardous waste, controlling air and water pollution, and ensuring that public health standards are upheld regarding toxic chemicals.

In contrast, while the FBI focuses on federal law enforcement and national security, OSHA (Occupational Safety and Health Administration) is concerned with workplace safety and health regulations, which may include some aspects of hazardous materials in occupational settings. The CDC (Centers for Disease Control and Prevention) primarily focuses on public health and disease control rather than environmental regulation. Hence, the EPA stands out as the dedicated authority for environmental matters, particularly those involving hazardous materials, making it the correct answer.