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Contaminants are substances that make water unfit for use. Some contaminants can be easily identified by assessing the taste, odor, and turbidity of the water. Most, however, cannot be easily detected and require testing to reveal whether or not water is contaminated. If left unchecked, contaminants can cause a whole host of water-related diseases which exact a terrible toll on human health.

Contaminants are either man-made or naturally occurring. Some contaminants are organisms that include pathogens like bacteria, viruses, and parasites such as microscopic protozoa and worms. These living organisms can be spread by human and animal waste. Good sanitation and hygiene can help to stop the spread of these organisms.

Other contaminants are the man-made byproducts of industry and agriculture including heavy metals like lead and mercury, and hazardous chemicals and compounds like insecticides and fertilizers.

Naturally occurring elements can contaminate water as well. Toxins such as the highly poisonous metal arsenic may be naturally present at unacceptable levels.

Contaminated water must be treated before it can be used for human consumption. Water treatment can occur in two distinct places: at a centralized water treatment facility and at the point of use.

Wherever treatment takes place, a diverse range of technologies is used to purify drinking water. Treatment technologies are selected and applied using several determining factors including water source, type of contaminant, and cost.

For the most effective treatment, a combination of technologies is used to insure water is fully decontaminated.


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