Water Contaminants 101

There are dozens of EPA-regulated water contaminants.

And their presence can have detrimental effects on both your health and home. Some of these contaminants have no color, taste or smell, which makes them difficult to detect without a professional water test.


Arsenic enters the water supply through its natural presence in bedrock, or as an industrial byproduct. The most concerning health risk posed by arsenic is low-level, long-term exposure via drinking water, and as a result, the possibility of increased occurrences of cancer and other health problems.

Chlorine Taste/Smell

The taste and smell of chlorine are unappealing and can also dry out your skin and hair. While municipalities use chlorine to disinfect the water supply, it should be filtered out before you use it to eliminate harmful/annoying effects.

Cloudy/Milky Water

Raw water comes into your home with any number of impurities that can cause turbidity. Tiny particles of clay can hang in suspension, giving the water an unpleasing cloudy appearance or cause your water to have a milky color.


Chromium-6, also known as hexavalent chromium, is a highly toxic contaminant. It may be released into groundwater as a result of certain industrial activities such as chrome plating, leather dying, wood preservation and stainless steel manufacturing process. Drinking water that has more than 0.02ppb of chromium-6 could cause cancer. Chromium-6 is too small to notice, even when it’s present in large amounts and affects 2 out of 3 every Americans.

Coliform and E. coli

Coliform bacteria include a group of 16 species comprising three groups: total coliform, fecal coliform, and E. coli. Bacterial contamination can be a result of septic system failure or agricultural runoff. Symptoms of infection can range from digestive problems such as diarrhea, vomiting, fatigue, and fever to severe conditions such as anemia and kidney failure. Advanced water filtration systems combining Reverse Osmosis and UV based deionization can get rid of most bacterial contaminants.


Lead seeps into the water supply from the lead pipes, solder and fixtures used extensively across the United States. There is no safe level of lead exposure, especially for children, who can suffer harmful and potentially chronic effects ranging from stomach pain to brain damage.


Magnesium is a mineral that enters water when rain soaks into the ground, running through sand, soil, and rock. The presence of magnesium creates hard water. Although this is not a direct health hazard, magnesium in water can cause buildup in pipes, shortened life spans for your appliances, increased soap and detergent use, dry skin, dull hair, and spotted dishes.


Nitrates are essential for food, flowers and greener lawns, which makes them a major ingredient in most fertilizers. Although nitrates are naturally occurring in soil, overuse of fertilizer is the largest cause of contamination. Nitrates spread on lawns and fields can move quickly through soil and grow more concentrated in groundwater, creating potential health risks for everyone, especially infants and pregnant women.


Radon is a colorless, odorless, tasteless gas that exists due to the radioactive decay of uranium, a common element in our bedrock that can cause cancer. Radon gas dissolves into groundwater and then is released into the air when a facet is turned on in your home or office.


Radium-226 is a highly radioactive chemical element. It is undetectable to human senses and can only be detected by professional testing. Long-term consumption of even low doses of radium at 5.0 pCi/L, the current EPA limit, can increase the likelihood of cancer, birth defects, and kidney damage. Up to 90 percent of radium can be removed from drinking water by Reverse Osmosis Water Systems.

Sulfur and Rotten Eggs

Hydrogen sulfide, a smelly, colorless gas that is produced by sulfur reducing bacteria sometimes found in groundwater. It causes a characteristic rotten egg smell that is prominent in hot water. Sulfur in drinking water can cause a laxative effect, leading to increased rates of diarrhea and dehydration, especially in infants and young children. It can also stain plumbing fixtures, toilets and sinks, while tarnishing silver and copper housewares. A Reverse Osmosis water filtration system is capable of removing most of the sulfur.

Culligan offers many water softening and drinking water solutions to solve a variety of water problems. Sign up for a free water analysis today to get softer, healthier water.