All sources of drinking water contain some naturally occurring contaminants. As water flows in streams, sits in lakes, and filters through layers of soil and rock it dissolves or absorbs the substances that it touches. According to its exposure, water transforms in composition and in physical parameters.

Aluminum (Al) Low level exposure is not thought to harm your health. Aluminum, however is not a necessary substance for our bodies and too much may be harmful. (Federal Limit 0.05 – 0.2 mg/L)

Antimony (Sb) Above the EPA limit antimony may potentially cause nausea, vomiting, and diarrhea. Antimony is a known/potential drinking water human carcinogen. (Federal Limit 0.006 mg/L)

Arsenic (As) Arsenic is a known human carcinogen. (Federal Limit 0.010 mg/L)

Barium (Ba) Symptoms of barium poisoning include increased blood pressure, changes in heart rhythm, stomach irritation, and muscle weakness. (Federal Limit 2.0 mg/L)

Beryllium (Be) Beryllium is a probable human carcinogen. (Federal Limit 0.004mg/L)

Boron (B) Exceptionally toxic to some plants. If you have problems with growing plants, it could be the water and not your green thumb! (Toxic range for plants is 1.0-4.0 mg/L)

Cadmium (Cd) Symptoms of cadmium poisoning include cramps, nausea, vomiting, and diarrhea. Long term exposure to lower levels of cadmium leads to kidney disease, lung damage and fragile bones. (Federal Limit 0.005mg/L)

Calcium (Ca) Calcium is an important contributor to water hardness. (No Federal Limit)

Conductivity: Conductivity gives an approximate determination of the amount of dissolved minerals in the water. (No Limit)

Chromium (Cr) Above the EPA limit chromium may potentially cause skin irritation or ulceration. Long term exposures to chromium may cause damage to liver, kidney, circulatory, and nerve tissues. (Federal Limit 0.1 mg/L)

Copper (Cu) Causes staining of fixtures, hair, and fabrics and can impart a bitter taste to water. It can cause stomach irritation and vomiting. (Federal Limit 1.0 mg/L)

Fecal Coliform Bacteria and Escherichia coli (E. coli) Present in the intestines of mammals. In the laboratory, coliforms are used as indicators of fecal contamination of ground and surface waters. Water sources containing any coliforms must be treated before consumption.

Fluoride (F) Long term effects are a permanent brown staining of the teeth, destruction of tooth enamel, brittle and easily broken bones, painful and stiff joints. (Federal Limit 4.0 mg/L, Oregon limit 2.0 mg/L)

Hardness is usually attributed to the calcium and magnesium ions. These ions combine with soap, forming an insoluble precipitate visible as scum and rings around fixtures. (Federal Limit 250 mg/L)

Iron (Fe) When iron comes in contact with oxygen, it oxidizes to a visible reddish compound that settles out as a rust-like material that stains clothing and fixtures. (Federal Limit 0.3 mg/L)

Lead (Pb) Symptoms of lead poisoning include tiredness and aching bones. (Federal Limit 0.015 mg/L)

Lithium (Li) Occurs naturally in Southern Oregon and is currently being monitored by NRC. (No Limit)

Magnesium (Mg) Magnesium is an important contributor to water hardness. When water is heated, magnesium breaks down and precipitates out of solution, forming scale. Magnesium concentrations greater than 125 mg/L may have a laxative effect. (No Limit)

Manganese (Mn) Produces a brownish discoloration, which stains clothing and fixtures. High levels of manganese are toxic to expectant mothers and children. (Federal Limit 0.05 mg/L)

Molybdenum: Excessive molybdenum consumption can be associated with enlarged liver, gastrointestinal, and kidney disorders. (USEPA Lifetime Health Advisory: 40 ug/L)

Nickel (Ni) Relatively short exposures above the EPA Limit are not known to cause any health problems. Long term exposures can potentially cause decreased body weight, skin irritation, heart, and liver damage. (Federal Limit 0. 1 mg/L)

Nitrate/Nitrite (NO2/NO3) Affects infants under the age of 6 months. In this age group nitrates reduce the blood’s ability to carry oxygen and may cause death or permanent brain damage. (Federal Limit Nitrate 10 mg!L, Nitrite 1 mg/L)

Pesticides & Herbicides Enter surface and ground water primarily as runoff and can remain in sediment for years. Thousands of chemicals are currently regulated by the EPA and have various hazardous effects on humans. (Federal Limit Per Each Analyte)

pH: The ideal pH for drinking water is 7.5. When pH is below 7.0, the water is acidic and can cause corrosion of pipes and fixtures. When the pH is higher than 8.0, the water is alkaline. This can create mineral deposits on the interior surfaces of pipes.

Potassium (K) To lower blood pressure, blunt the effects of salt, and reduce the risk of kidney stones and bone loss, adults should consume 4.7 grams of potassium per day. (No Limit)

Selenium (Se) Is an essential nutrient at low levels. However, levels above 0.05 ppm may cause: hair and fingernail changes; damage to the peripheral nervous system; fatigue and irritability. Long term exposures to selenium may cause hair and fingernail loss, damage to kidney and liver tissue and the nervous and circulatory systems. (Federal Limit 0.05 mg/L)

Silica: Silica analysis provides useful information for systems that my require water treatment.  Not identified as a health hazard. (No Limit)

Silver (Ag) Silver poisoning causes a blue-gray discoloration of the skin, mucous membranes, and eyes. In high doses it is fatal to humans. (Federal Limit 0.1 mg/L)

Sodium & Chloride (Na/Cl2) If the sodium and chloride levels are near 100 mg/L, individuals may notice a salty taste. These levels also affect plant growth. (Sodium: No Limit) (Chloride: Federal Limit is 250 mg/L)

Sulfate (SO4) Sulfate is a substance that occurs naturally. It may be found in the form of hydrogen sulfide and is commonly identified by a “rotten egg odor.” Diarrhea may be associated with the ingestion of high levels of sulfate. (Federal Limit 250 mg/L)

Thallium (Tl) Above the EPA limit thallium may potentially cause gastrointestinal irritation and nerve damage. Long-term exposures to thallium may cause changes in blood chemistry, hair loss, damage to liver, kidney, intestinal, and testicular tissues. (Federal Limit 0.002 mg/L)

Turbidity: Turbidity is the lack of clarity or brilliance in water. This can affect water treatment systems such as UV lights for disinfection, reverse osmosis units, sediment removal systems, and ion exchange treatment systems. (Federal Limit 1 NTU)

Uranium: Naturally occurring substance that is mildly radioactive. Exposure to high levels of uranium can cause kidney disease. (Federal Limit 0.03 mg/L)

Vanadium: The health effects in humans has not been established. Studies in pregnant animals showed minor birth defects. Vanadium ingested over a long period of time also revealed minor kidney and liver changes. Vanadium is also used for arsenic removal in drinking water treatment systems. (No Limit)

Volatile Organics (VOCs) are found in gasoline, dry cleaning solvents, degreasing agents and other industrial solutions. The EPA and DEQ monitor thousands of chemicals that fall under this classification. (Federal Limit Per Each Analyte)

Zinc (Zn) High levels of zinc can cause stomach cramps, nausea, and vomiting. Over a long period of time it can cause anemia and pancreas damage. (Federal Limit 5.0 mg/L)

For a complete list of all regulated contaminants and the maximum levels as established by the EPA, see the following page:

https://www.epa.gov/dwstandardsregulations