Read the special issue from the U.S. Geological Survey.
Natural toxins are toxic chemicals produced by living organisms and are present in many areas across the globe where humans, pets, livestock, and wildlife live. For example, there are natural toxins in some wild mushrooms, which are highly toxic upon ingestion, and in snake venom. The hazards posed by these and some other toxins are widely understood to cause serious illness or death to humans and other organisms upon exposure if the toxin is present in a high enough dose. Fortunately, even though these and other toxins commonly exist in the environment, most humans are never exposed and therefore the overall human-health risk is generally low in our everyday lives. U.S. Geological Survey (USGS) science helps understand the transport, fate, exposure pathways, and health effects of a variety of environmental toxins for which much less information is available.