Society’s ability to solve problems through innovation is incredible and great benefits are enjoyed by many. Unfortunately sometimes innovation involves substances that can be toxic to human, animal and plant health. Some advances in pharmaceuticals, agriculture and industry may involve new chemicals or create new waste products. These substances may become an environmental contaminant if they accidentally or deliberately enter the environment through industrial and commercial facilities; oil and chemical spills; non-point sources such as roads, parking lots and storm drains; and wastewater treatment plants and sewage systems. 

The U.S. Environmental Protection Agency's defines a contaminant as "Any physical, chemical, biological, or radiological substance or matter in air, water, or soil that can have adverse health effects." Different contaminants can cause a variety of human health and environmental problems. Below are contaminants common in Missouri and new or unstudied contaminants, sometimes referred to as an emerging contaminant.

Cyanobacteria – Harmful Algal Blooms, Blue-Green Algae
Algal blooms can cause fish kills; blue-green algae can make people and animals sick
When present in high levels, lead presents a threat to human health and the environment
Mercury exposure can cause neurological and developmental disorders in humans
The national opioid crisis affects thousands of people every day
Per- and Polyfluoroalkyl Substances (PFAS)
Found in industry and consumer products, PFAS may cause harmful human health effects
Misuse of pesticides can cause health effects, including respiratory problems and cancer
Some pharmaceuticals appearing in drinking water are known endocrine disrupters