Top 20 Contaminants Identified in Drinking Water for
Southern Oregon and Northern California

This group has been identified after years of data collection by Neilson Research Corporation from water sources all over Southern Oregon and Northern California. This is the series of tests that will enable you to identify the presence of contaminants which generally cannot be seen, tasted, or smelled.

Aluminum: Federal Limit: 0.05 - 0.2 mg/L.  Highest Value Found: 16.3 mg/L
EPA recommends that the concentration of aluminum in drinking water not exceed 0.2 mg/L because of aesthetic effects, such as taste and odor problems.

Arsenic: Federal Limit: 0.010 - 0.050 mg/L  – Highest Value Found: 3.88 mg/L
The current EPA limit for Arsenic is 0.050 mg/L.  This will change to 0.010 mg/L on January 22, 2006. Symptoms of arsenic poisoning include weight loss, nausea, diarrhea, hair loss, depression, tiredness, and intestinal upsets. Long term effects are circulatory diseases, skin and other cancers. News about Arsenic.  EPA's Arsenic Rule

Barium: Federal Limit: 2 mg/L
EPA has established a limit of 2 mg/L in drinking water.

Boron: Federal Limit: No maximum drinking water limit, EPA is considering 0.6 mg/L.   Highest Value Found: 179 mg/L.
The recommend limits for agriculture is 1 - 4 mg/L. Boron is Included in this package because it is exceptionally toxic to plants and is commonly requested by homeowners. Plants can tolerate from 1.0 to 4.0 mg/L. If you have problems with growing plants, it could be the water and not your green thumb!

Cadmium: Federal Limit: 0.005 mg/L.
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. Cadmium can get into the water by corrosion of some types of galvanized piping, or by improper disposal of wastes from households, industries, and automotive repairs.

Calcium and Magnesium: No Federal Limits
They are essential nutritional elements. Calcium and Magnesium is commonly requested by homeowners. It is used to calculate Hardness.

Chloride: Federal Limit: 250 mg/L – Highest Value Found: 6,700 mg/L
Homeowners with a chloride level of 100 mg/L or more may complain of a salty taste after the installation of a water softener.

Conductivity: No Federal Limits - Highest Found: 24,500
The information from this test is used to give an approximate determination of an amount of dissolved minerals in the water suppy.

Copper: Federal Limit: 1.0 mg/L with an Action Level at 1.3 mg/L for Public Water Systems.
Highest Value Found: 5.27 mg/L
Can cause staining of fixtures, hair and fabrics. Also imparts a bitter taste to water. At high levels can cause stomach irritation and vomiting.

Fluoride: Federal Limit: 4 mg/L. Oregon limit 2.0 mg/L: - Highest Value Found: 15.56 mg/L
Long term effects are a permanent brown staining of the teeth, destruction of tooth enamel, brittle and easily broken bones, painful and stiff joints.

Hardness: Federal Limit: 250 mg/L – Highest Value Found: 5,000 mg/L
The term "hardness" is applied to the soap-neutralizing power of water. Hardness is usually attributed to the calcium and magnesium ions. These ions combine with soap to form an insoluble precipitate often seen as scum on the water and a ring around the bathtub. Iron and manganese can also contribute to the hardness of water.

Iron: Federal Limit: 0.3 mg/L – Highest Value Found: 88.07 mg/L
This is a common problem. In the aquifer (water bearing stratum) iron is usually present in the reduced form because of the absence of oxygen. In this form, iron is soluble in water and is not visible. However, when the iron comes in contact with oxygen, it oxidizes to the visible reddish compound that settles out as rust-like material which stains clothing and fixtures.

Lead: Federal Limit: 0.015 mg/L (Action Level) – Highest Value Found: 3.1 mg/L
This is a very protective standard and is aimed at protecting pregnant women and small children. Public water systems found to have levels of lead above this standard are required to install corrosion control treatment to reduce the aggressiveness of the water, preventing or reducing the leaching of lead into the water 

Manganese: Federal Limit: 0.05 mg/L – Highest Value Found: 11.4 mg/L
The chemistry of manganese in water is identical to that of iron, with the exception that manganese produces a brownish, rather than a red discoloration. In addition, a high level of manganese produces a very unpleasant odor/taste in water. High levels of manganese are toxic to expectant mothers and children.

Nitrate: Federal Limit: 10.0 mg/L – Highest Value Found: 48.74 mg/L
This chemical effects infants under the age of 6-9 months. In this age group nitrates reduce the blood's ability to carry oxygen and may cause death or permanent brain damage to the child. High nitrate levels also cause gastric and stomach cancers.

pH: Federal Limit: 6.5-8.5 pH Units – Range Found: 4.78 -11.4 pH Units
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 and the water will have a slippery feeling.

Sodium: No Federal Limit:  Advisory limit of 20 mg/L for those individuals on a 500 mg/day medical restriction.
Highest Natural Value Found: 2,841 mg/L.
There is not enforceable limit on sodium. If the sodium level approaches 100 mg/L and the chloride level is near 100 mg/L, individuals may notice a salty taste to the water. These levels also effect plant growth.

Sulfate: Federal Limit: 250 mg/L - Highest Value Found: 1630 mg/L
Sulfate is a substance that occurs naturally. Diarrhea may be associated with the ingestion of high levels of sulfate.

Zinc: Federal Limit: 5.0 mg/L – Highest Value Found: 32.3 mg/L
Gives the water a metallic taste. Can cause a greasy film on boiling. High levels give water a milky appearance. Zinc bearing water should not be used in acid drinks like lemonade because zinc citrate and other organic zinc compounds that will result may be poisonous.