Environmental Toxicology is the multidisciplinary study of the effects of manmade and natural chemicals on health and the environment. This includes the study of the effects of chemicals on organisms in their natural environments and in the ecosystems to which they belong.Environmental toxicologists work in academia, companies, government agencies, and elsewhere. The work can include laboratory studies, computer modeling, and work "in the field." It is not unusual for an environmental toxicologist to also have training in other areas—for example, public health, environmental chemistry, and pharmacology.

Some examples of what Environmental Toxicologists study include: The effects of a chemical or other substance at various concentrations on various species.Whether a chemical or other substance can bioaccumulate (increase over time) in animals or other organisms. This is important for human exposures if the bioaccumulation occurs in animals that are part of the human food chain, such as fish. Emerging issues such as the study of the sources and effects of microplastics that could become part of the human food chain. Another emerging global issue is the health of bees. In the news in recent years are terms like the Colony Collapse Disorder (CCD), pesticides like the neonicotinic pesticides (also called neonicotinoids), and parasites that only reproduce in bee colonies. About 75% of all flowering plants rely on animal pollinators and about one-third of our food production is dependent on animal pollinators. The general declining health of honeybees and other bees is thought to be related to complex interactions among multiple stressors, including pesticides and parasites, and stressors like poor nutrition due to declining foraging habitats, bee management practices, and a lack of genetic diversity.