Contaminants and Pathogens

What is in that water that you just drank? Is it just hydrogen and oxygen atoms? Is it safe for drinking? All water is of a certain "quality" (and you can't tell by just looking), but what does "water quality" really mean? It can be thought of as a measure of the suitability of water for a particular use based on selected physical, chemical, and biological characteristics. Here at the Water...

Mercury has got to be one of the most fascinating elements around. In looking at the bubbles of bright silver sitting on a flat surface, it is easy to see why mercury is also called "quicksilver." Mercury is the only metal that exists in liquid form. It may act somewhat like water, but it is nothing at all like water, especially in the potential harmful effects it can have on humans and ecosystems...

Mine drainage is metal-rich water formed from a chemical reaction between water and rocks containing sulfur-bearing minerals. Problems that can be associated with mine drainage include contaminated drinking water, disrupted growth and reproduction of aquatic plants and animals, and the corroding effects of the acid on parts of infrastructures such as bridges.

Commercial pesticide applicators, farmers, and homeowners apply about 1 billion pounds of pesticides annually to agricultural land, non-crop land, and urban areas throughout the United States. The use of pesticides has helped to make the United States the largest producer of food in the world and has provided other benefits, but has also been accompanied by concerns about their potential adverse...

Groundwater will normally look clear and clean because the ground naturally filters out particulate matter. But did you know that natural and human-induced chemicals can be found in groundwater even if appears to be clean? Below is a list of some contaminants that can occur in groundwater.

Collecting samples of water isn't the only way to test water quality. The USGS actually collects fish to see if and how they were affected by local pollution and chemicals in the water, such as pesticides. Read on to find out more.

Groundwater is crucial to millions of Americans as well as many more worldwide. Groundwater provides drinking water to many. Thus, having reliably clean groundwater is of concern for many throughout the world. But, groundwater can become contaminated with chemicals, biologic organisms, and other possibly-harmful agents.

There is a growing concern about the occurance of pharmaceuticals in water bodies and in drinking water. Pharmaceuticals get into the water supply via human excretion and by drugs being flushed down the toilet. You might think wastewater treatment plants would take care of the situation, but pharmaceuticals pass through water treatment.

Water, like everything else on Earth, including you, is full of bacteria. Some bacteria are beneficial and some are not. Escherichia coli ( E. coli ) bacteria, found in the digestive tract of animals, can get into the environment, and if contacted by people, can cause health problems and sickness. Find out the details here.