What's in Water? Types of Pollutants
First, let's divide our water pollutants into two categories.
Nuisance pollutants and life threatening pollutants.
Nuisance pollutants are those that cause discomfort. The water can look funny, smell funny or taste wrong. They also render soap and washing ineffective.
Types of Health Threatening Pollutants
- Toxic minerals or metals
- Organic Chemicals
- Radioactive substances
Microorganisms include harmful bacteria, viruses and parasites. They can cause such diseases as Typhoid, cholera, hepatitis and flu.
Bacteria is closely monitored in public water supplies, because they can be dangerous, and because their presence is easily detected. Tap water from a public water supply is generally free of dangerous concentrations of bacteria because they are killed when chlorine is added.
Viruses are very common in water. Research has shown that a teaspoon of unpolluted lake water contains over a billion viruses. Viruses are much smaller than bacteria and harder to detect. Although disinfecting tap water with chlorine probably kills the majority of viruses, no one knows for sure how many remain potent.
It is more difficult to test for the presence of viruses in water than it is for bacteria, and most water testing laboratories do not have the ability to do this. While most waterborne viruses appear to be harmless to humans, some are the cause of cold and flu epidemics. Harmful viruses can be present in tap water even though a water treatment plant is operating properly.
A third group of microorganisms commonly found in water is protozoan parasites. The two most common and troublesome of these are called giardia and cryptosporidium. In water, these parasites occur in the form of hard shelled cysts. Their hard covering protects them from the chlorine disinfectants that kills other microorganisms. Both of these parasites cause mild to severe gastrointestinal symptoms in healthy people. In people with impaired immune systems, they can be life threatening. Parasites can be present in tap water even though a water treatment plant is operating properly.
In spite of the effective elimination of bacteria in public water supplies, other microorganisms in the water can be a serious health hazard.
Toxic minerals are the harmful inorganic substances that are found in water supplies. Inorganic means not derived from plants or animal matter. They include metals as well as common minerals in the form of rock, and sand clay.
It is important to distinguish between harmful minerals and minerals that are just a nuisance.
The main nuisance
- Calcium and magnesium, which cause hardness in water
- Iron and maganese, which cause staining
- Hydrogen sulfide gas, which causes a rotten egg-like odor.
The minerals that are actually harmful to health in water are:
- Aluminum - Arsenic - Asbestos - Barium
- Cadmium - Chromium - Copper - Floride
- Lead - Mercury - Nitrate - Nitrite
- Selenium - Silver
There are also 100,000 different manufactured, or synthetic, organic chemicals in commercial use today. They include synthetic fertilizers, pesticides, herbicides, paints, fuels, plastics, dyes, flavorings, pharmaceuticals and preservatives, to name a few. Many of these chemicals are toxic, and thousands of them have been found in public water supplies.
One type of organic chemical is particularly dangerous. Volitile organic chemicals or VOC's, are absorbed through your skin when you come in contact with water, as in a shower or bath. Further, hot water allows these chemicals to evaporate rapidly, and they are harmful if inhaled. VOC's can be in any tap water, reguardless of where you live or what your source of water is. If your tap water should contain significant levels of these kinds of chemicals, they will be a health threat from skin contact with the water even if you don't drink it.
In addition to these organic chemicals that could get into the water, new and dangerous ones are created in water itself. All US tap water has Chlorine, and combines with organic chemicals to form a category of toxic pollutants called THM's or trihalomethanes. THM's are known as carcinogens. They are substances that increase the risk of getting cancer, and they are present at varying levels in all tap water.
Radioactive substances in water are of two types, radioactive minerals and radioactive gas. If the source of your water is a reservoir, river or mountain that is near or downstream from either mining areas or nuclear facilities, you should pay special attention to finding out the level of radioactivity in your water.
Dangers of Radon
More importantly, there is a far more dangerous threat in the form of Radon. Radon is colorless, odorless, naturally occurring gas that is the by product of decay of radioactive materials. Radon is a known cancer causing agent.
When present in household water, it evaporates easily into the air and is inhaled. The effects of radon inhalation are now believed to be more dangerous than those of any other environmental hazard.