It is a homeowner's responsibility for testing their well for microbiological contaminants such as coliform bacteria. Additionally, many homeowners want to know what other minerals and/or contaminants may be dissolved in their water supply. Private testing labs can provide complete inorganic analyses. Listed below are the most common elements and parameters which will typically be tested and reported.

Aluminum
Aluminum, the most abundant metal on Earth, is found in soil, in water and in air. Its chemical and physical properties make it ideal for a wide variety of uses. For example, aluminum and its compounds are often used in food as additives, in drugs (e.g., antacids), in consumer products (e.g., cooking utensils, anti-perspirant and aluminum foil) and in the treatment of drinkingwater (e.g., coagulants).

Because aluminum is so pervasive in the environment, to the point of being unavoidable, researchers have long been studying its effects on humans. This research has revealed a link between aluminum intake and neurological dementia in kidney dialysis patients (dialysis encephalopathy). In recentyears, the public and the media have become concerned about other possible adverse effects of aluminum on human health, including its role in Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis (Lou Gehrig's disease). In addition, questions have been raised about the potential risks to infants who drink baby formula containing aluminum.

Arsenic
Most arsenic enters water supplies either from natural deposits in the earth or from industrial and agricultural pollution. Arsenic is a natural element of the earth's crust. It is used in industry and agriculture, and for other purposes. It also is a byproduct ofcopper smelting, mining and coal burning. U.S. industries release thousands of poundsof arsenic into the environment every year.

According to a 1999 study by the National Academy of Sciences, arsenic in drinking water causes bladder, lung and skin cancer, and may cause kidney and liver cancer. The study also found that arsenic harms the central and peripheral nervous systems, as well as heart and blood vessels, and causes serious skin problems. It also may cause birth defects and reproductive problems.

Barium
Barium is a lustrous, machinable metal which exists in nature only in ores containing mixtures of elements. It is used in making a wide variety of electronic components, in metal alloys, bleaches, dyes, fireworks, ceramics and glass. In particular, it is used inwell drilling operations where it is directly released into the ground. Short-term: EPAhas found barium to potentially cause the following health effects when people are exposed to it at levels above 2 ppm for relatively short periods of time: gastro-intestinal disturbances and muscular weakness. Long-term: Barium has the potentialto cause high blood pressure from a lifetime exposure at levels above the MCL.

Boron
Boron is a naturally occurring element. In the environment, boron is combined with oxygen and other elements in compounds called borates. Borates are widely found in nature, and are present in oceans, sedimentary rocks, coal, shale and some soils. There are several commercially important borates, including borax, and boric acid, and have many industrial uses in glass making, leather preservation, in welding and fertilizers.

Everyone is exposed regularly to small amounts of boron in food. Generally the amounts pose no harm because boron is regularly excreted in feces and urine over a period of several days. Children and infants on which boron compounds are used for medication can become acutely ill with nausea, vomiting, diarrhea, circulatory collapse, skin rash and confusion. Fatal poisonings often involve kidney failure.

It is beneficial to plants only within narrow limits, and excesses are injurious and even lethal to plants. Regular use of irrigation water with more than 1 ppm boron is harmful to most kinds of plants.

Cadmium
Cadmium is released into the environment from mining and metal processing operations, burning fuels, making and using phosphate fertilizers, and disposing of metal products. Cadmium is not mined, but it is a by-product of the smelting of other metals such as zinc, lead, and copper. Cadmium is used in nickel-cadmium rechargeable batteries and for metal plating. It also is used in some paints, plastics, and metal solders.

Cadmium is found naturally in small quantities in air, water, and soil. Since cadmium is a metal, it does not break down and can accumulate over time. Burning household or industrial waste and burning coal or oil may release cadmium into the air. Cadmium can enter the body from smoking tobacco, eating food and drinking water containing cadmium, and inhaling it from the air.

Cadmium has no beneficial effect on human health. Health effects caused by cadmium depend on how much has entered the body, how long you have been exposed to cadmium, and how the body responds. Some workers who breathe air with high levels of cadmium over a short time experience lung damage and even death. Breathing cadmium in air does not usually cause immediate breathing problems or any warning signs. Therefore, exposure may continue until serious lung damage has occurred.

Most cadmium levels found in the environment are not high enough to cause lung damage. Breathing lower levels of cadmium over several years can result in a buildup of cadmium in the kidneys and lead to kidney disease. It also can cause bones to become weaker. If you eat food or drink water that contains large amounts of cadmium, stomach irritation, vomiting, and diarrhea may result. Smallamounts of cadmium taken in over many years may cause kidney damage and fragile bones.

Chlorine
The experimental use of chlorine began in the 1890's to combat water-borne diseases such as cholera and typhoid. It quickly gained wide acceptance because of low cost and high efficiency in killing just about everything hazardous in the water. Chlorine allowed population centers to spring up and thrive without any epidemic outbreaks.

The problem with chlorine is that it is a known poison and the safety of drinking this poison over the long term (i.e. your lifetime) is highly uncertain. Also, chlorine reacts with water-borne decaying organic matter like leaves, bark, sediment, etc. to create a family of chemicals called trihalomethanes and other highly toxic substances. Trihalomethanes, or THM's, include chemicals such as chloroform, bromoform and dichlorobromethane, all of which are extremely carcinogenic even in minute amounts.

If you are on a municipal system with chlorination, theoretically you are protected against bacteria. However, if the level of chlorination isn't high enough from the municipal source to your tap, bacteria can re-infect the water anywhere along the distribution system. The piping system -- whether it's the public water mains or your house plumbing -- has bacterial growth in it happening all the time.

If you are on a spring or a well, with no chlorine, then you are very vulnerable to bacterial contamination. Even the most pure sources cannot prevent occasional contamination from animals either dying or defecating in the source, or from neighboring pollution (i.e. septic tanks) traveling from an adjoining watershed to contaminate the source. Also, the pipes are again a source of bacteria. Many people do periodic testing on their well or spring source and rely on this method to assure themselves that they have good water.

Copper
Copper rarely occurs naturally in water. Most copper contamination in drinking water happens in the water delivery system, as a result of corrosion of the copper pipes or fittings. Copper piping and fittings are widely used in household plumbing. Generally, naturally soft water is more corrosive than hard water because it is more acidic and has low TDS.

At very high levels, copper can cause a bitter metallic taste in water and result in blue-green stains on plumbing fixtures. At low levels, copper in drinking water may cause no health symptoms. At high levels, copper in drinking water may cause symptoms easily mistaken as flu or other illnesses. Thus health symptoms are not a reliable indication of copper in drinking water.

Although copper is an essential micronutrient and is required by the body in very small amounts, excess copper in the human body can cause stomach and intestinal distress such as nausea, vomiting, diarrhea and stomach cramps. The lowest level at which these adverse effects occur has not been well defined. People with Wilson's disease, a rare genetic disorder, are more sensitive to the effects of copper.

Fluoride
Waters with high fluoride content are found mostly in calcium-deficient waters in many basement aquifers, such as granite and gneiss, in geothermal waters and in some sedimentary basins. Fluorides in water can be detrimental or beneficial. It all depends on the concentration. Surface water supplies are normally low in fluorides (less than 0.5 ppm). Some have no fluoride at all. Well waters may contain excessive amounts of fluoride. There are some wells which contain the recommended amount (1 mg/L) for drinking water.

Fluorides are important because they have a definite relation to dental health. Research has shown that a concentration of 1 mg/L of fluoride in drinking water reduces tooth decay. On the other hand, some children under nine years of age exposed to levels of fluoride greater than about 2 mg/L may develop a condition known as "endemic dental fluorosis." Sometimes called "Colorado Brown Stain," this condition appears as a dark brown mottling or spotting of the permanent teeth. In certain cases, the teeth become chalky white in appearance. Further,federal regulations require that fluoride not exceed a concentration of 4 mg/L in drinking water. This is an enforceable maximum contaminant level standard, and it has been established to protect public health. Exposure to drinking water levels above 4 mg/L for many years may result in cases of crippling skeletal fluorosis, which is a serious bone disorder.

Lead
Lead rarely occurs naturally in water. Most lead contamination takes place at some point in the water delivery system. Lead pipes and lead solder in the distribution system are the main sources of lead pollution. Boston Globe estimates that 98% of all households have lead in their plumbing. Houses older than 20 years and less than five years are most at risk. Also, houses in areas of soft (low mineral levels) water tend to corrode the lead from the pipes more easily.

Lead is a cumulative toxin that stays in the tissue permanently, especially in brain tissue. It also affects a person in relation to their body weight. Therefore, an exposed adult can fend off the toxic effects for some time but in children, brain and developmental damage occur quickly and permanently.

Exposure to low levels of lead over an extended period of time can have severe health effects. Too much lead can damage your brain, kidneys, nervous system, and red blood cells. Those at the greatest risk, even with short-term exposure, are young children and pregnant women. According to the U.S. Environmental Protection Agency (EPA), lead dosage that would have little effect on an adult can harm a small child. Lead in drinking water can be a problem for infants whose diet consists of liquids -- such as baby formula made with water. Since they are growing, children absorb lead more rapidly than adults. That lead can then impair a child's development, resulting in learning disabilities or stunted growth.

Magnesium
Magnesium is present in all natural waters and enters the groundwater the same way as calcium by contact with rock formations. Magnesium is associated with calcium and is also a major contributor to hardness. As well, magnesium may contribute to undesirable tastes in your water if the concentration is high. When present in water with sulfates, magnesium may have a laxative effect or cause gastrointestinal irritation.

Manganese
Manganese is a mineral that naturally occurs in rocks and soil and is a normal constituent of the human diet. It exists in well water as a groundwater mineral, but may also be present due to underground pollution sources. You may suspect that manganese is in your water if the water is discolored (brownish-red), causes staining of plumbing fixtures or clothing or has an off-taste or odor. Exposure to high concentrations of manganese over the course of years has been associated with toxicity to the nervous system, producing a syndrome that resembles Parkinson Disease.

Sodium
Sodium is a naturally occurring mineral which is found in water sources. While sodium is not regulated as a contaminant in drinking water, it may have an effect on the consumer's health. In general, the sodium contributed to an individual's diet from drinking water is a small part of overall dietary intake. The American Heart Association's recommended standard for daily sodium intake is 3,000 milligrams. Persons on severely restricted sodium diets may want to consult their health professional regarding sodium levels in water. Water softeners can add sodium to your household water supply as well.

Zinc
Although zinc occurs naturally, most zinc finds its way into the environment because of human activities. Mining, smelting metals (like zinc, lead and cadmium) and steel production, as well as burning coal and certain wastes can release zinc into the environment. Zinc is frequently used as a protection to “galvanize” steel. When high levels of zinc are present in soils, such as at a hazardous waste site, the metal can seep into the groundwater. Zinc can enter the body if you eat foods or drink water or other beverages containing zinc, or if you breathe zinc dust or fumes from the air. Very small amounts of zinc enter the body through skin contact. Foods naturally contain zinc but vary greatly in their zinc content. Very small amounts of the zinc in food are absorbed by the body. Drinking beverages stored in metal cans or drinking water that flows through metal pipes coated with zinc also are sources of zinc exposure.

Zinc is an essential nutrient needed by the body for growth, development of bones, metabolism and wound-healing. Too little zinc in the diet also can cause adverse health effects such as loss of appetite, decreased sense of taste and smell,lowered ability to fight off infections, slow growth, slowwound-healing and skin sores.