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Home Lead Screen

Lead poisoning can cause severe health problems, including damage to the liver, kidneys, brain, nerves, bones and blood. Children are especially at high risk because they routinely ingest non-food items contaminated with lead. Toxic levels of lead can cause permanent learning disabilities, retardation and even brain damage in young children. Documentation reveals that serious behavioral problems and learning disabilities are seven times more likely to occur in children exposed to low levels of lead over an extended period of time (The New England Journal of Medicine-January 11, 1990). In adults, lead poisoning can cause high blood pressure and reproductive problems. In pregnant women, the fetus is particularly vulnerable to the toxic effects of lead.

Symptoms of lead poisoning can include fatigue, pallor, loss of appetite, irritability, sleep disturbance, sudden behavioral change and developmental regression.

Lead poisoning can occur through contact with plastic or vinyl miniblinds, vertical blinds, toys, painted surfaces, chipped paint, ceramic tile, porcelain fixtures, dinnerware, pottery, crystal, food containers, lead foils (wine and champagne bottles), soil and water (through solder in piping).
Inexpensive and easy to use, disposable LeadCheck Swabs work on any surface- ceramics, crystal, metals, paint, dust and soil- instantly turning bright pink when lead is present. There is even a test confirmation card to ensure that instructions have been followed to the letter!

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Blood  or Urine  Mercury Screen

People in the U.S. are mainly exposed to methyl mercury, an organic compound, when they eat fish and shellfish that contain methyl mercury. Whether an exposure to the various forms of mercury will harm a person's health depends on a number of factors (below). Almost all people have at least trace amounts of methyl mercury in their tissues, reflecting methyl mercury's widespread presence in the environment and people’s exposure through the consumption of fish and shellfish. People may be exposed to mercury in any of its forms under different circumstances. The factors that determine how severe the health effects are from mercury exposure include these:

• the dose -- how much

• the duration of exposure -- how long                   

• the route of exposure -- eating, breathing, injecting, touching

•  the age and health of the person

• the chemical form of mercury - elemental (metallic), inorganic compounds, or organic compounds

Mercury exists in three chemical forms. They each have specific effects on human health.

• Methyl mercury
• Elemental mercury
• Other mercury compounds (inorganic and organic)
   

Methyl mercury effects
 

For fetuses, infants, and children, the primary health effect of methyl mercury is impaired neurological development. Methyl mercury exposure in the womb, which can result from a mother's consumption of fish and shellfish that contain methyl mercury, can adversely affect a baby's growing brain and nervous system. Impacts on cognitive thinking, memory, attention, language, and fine motor and visual spatial skills have been seen in children exposed to methyl mercury in the womb.
Outbreaks of methyl mercury poisonings have made it clear that adults, children, and developing fetuses are at risk from ingestion exposure to methyl mercury. During these poisoning outbreaks some mothers with no symptoms of nervous system damage gave birth to infants with severe disabilities, it became clear that the developing nervous system of the fetus may be more vulnerable to methyl mercury than is the adult nervous system.
For more information on fish consumption advisories across the country, visit EPA's fish consumption web pages.
In addition to the subtle impairments noted above, symptoms of methyl mercury poisoning may include; impairment of the peripheral vision; disturbances in sensations ("pins and needles" feelings, usually in the hands, feet, and around the mouth); lack of coordination of movements; impairment of speech, hearing, walking; and muscle weakness. People concerned about their exposure to methyl mercury should consult their physician.
 

Elemental mercury effects

Elemental (metallic) mercury primarily causes health effects when it is breathed as a vapor where it can be absorbed through the lungs. These exposures can occur when elemental mercury is spilled or products that contain elemental mercury break and expose mercury to the air, particularly in warm or poorly-ventilated indoor spaces. Symptoms include these: tremors; emotional changes (e.g., mood swings, irritability, nervousness, excessive shyness); insomnia; neuromuscular changes (such as weakness, muscle atrophy, twitching); headaches; disturbances in sensations; changes in nerve responses; performance deficits on tests of cognitive function. At higher exposures there may be kidney effects, respiratory failure and death. People concerned about their exposure to elemental mercury should consult their physician.
 

Effects of other mercury compounds (inorganic and organic)

High exposures to inorganic mercury may result in damage to the gastrointestinal tract, the nervous system, and the kidneys. Both inorganic and organic mercury compounds are absorbed through the gastrointestinal tract and affect other systems via this route. However, organic mercury compounds are more readily absorbed via ingestion than inorganic mercury compounds.
Symptoms of high exposures to inorganic mercury include: skin rashes and dermatitis; mood swings; memory loss; mental disturbances; and muscle weakness. People concerned about their exposure to inorganic mercury should consult their physician.

Blood levels of mercury should not exceed 3.6 ug/dL, while urine levels should not exceed 15 ug/dL. Symptoms of mercury poisoning may be seen when mercury levels exceed 20 ug/dL in blood and 60 ug/dL in urine. Mercury levels in hair may be used to gauge the severity of chronic mercury exposure.

EPA-FDA Joint Federal Advisory for Mercury in Fish: “What You Need to Know About Mercury in Fish and Shellfish” - The purpose of the advisory is to inform women who may become pregnant, pregnant women, nursing mothers and the parents of young children on how to get the positive health benefits from eating fish and shellfish, while minimizing their mercury exposure

                 http://www.epa.gov/waterscience/fish/

 

Blood or Urine Cadmium Screen

What is cadmium?
 

Cadmium is a natural element in the earth's crust. It is usually found as a mineral combined with other elements such as oxygen (cadmium oxide), chlorine (cadmium chloride), or sulfur (cadmium sulfate, cadmium sulfide).
All soils and rocks, including coal and mineral fertilizers, contain some cadmium. Most cadmium used in the United States is extracted during the production of other metals like zinc, lead, and copper. Cadmium does not corrode easily and has many uses, including batteries, pigments, metal coatings, and plastics.

What happens to cadmium when it enters the environment?
 

• Cadmium enters air from mining, industry, and burning coal and household wastes.

• Cadmium particles in air can travel long distances before falling to the ground or water.

• It enters water and soil from waste disposal and spills or leaks at hazardous waste sites.

• It binds strongly to soil particles.

• Some cadmium dissolves in water.

• It doesn't break down in the environment, but can change forms.

• Fish, plants, and animals take up cadmium from the environment.

• Cadmium stays in the body a very long time and can build up from many years of exposure to low levels

• How might I be exposed to cadmium?

• Breathing contaminated workplace air (battery manufacturing, metal soldering or welding).

• Eating foods containing it; low levels in all foods (highest in shellfish, liver, and kidney meats).

• Breathing cadmium in cigarette smoke (doubles the average daily intake).

• Drinking contaminated water.

• Breathing contaminated air near the burning of fossil fuels or municipal waste.
   

How can cadmium affect my health?
 

Breathing high levels of cadmium severely damages the lungs and can cause death. Eating food or drinking water with very high levels severely irritates the stomach, leading to vomiting and diarrhea. Long-term exposure to lower levels of cadmium in air, food, or water leads to a buildup of cadmium in the kidneys and possible kidney disease. Other long-term effects are lung damage and fragile bones.
Animals given cadmium in food or water had high blood pressure, iron-poor blood, liver disease, and nerve or brain damage.
We don't know if humans get any of these diseases from eating or drinking cadmium. Skin contact with cadmium is not known to cause health effects in humans or animals.

How likely is cadmium to cause cancer?
 

The Department of Health and Human Services (DHHS) has determined that cadmium and cadmium compounds may reasonably be anticipated to be carcinogens.

How does cadmium affect children?
 

The health effects in children are expected to be similar to those in adults (kidney, lung and intestinal damage).
We don't know if cadmium causes birth defects in people. Cadmium does not readily go from a pregnant woman's body into the developing child, but some portion can cross the placenta. It can also be found in breast milk. The babies of animals exposed to high levels of cadmium during pregnancy had changes in behavior and learning ability. Cadmium may also affect birth weight and the skeleton in developing animals.
Animal studies also indicate that more cadmium is absorbed into the body if the diet is low in calcium, protein, or iron, or is high in fat. A few studies show that younger animals absorb more cadmium and are more likely to lose bone and bone strength than adults.
 

How can families reduce the risk of exposure to cadmium?
 

In the home, store substances that contain cadmium safely, and keep nickel-cadmium batteries out of reach of young children. If you work with cadmium, use all safety precautions to avoid carrying cadmium-containing dust home from work on your clothing, skin, hair, or tools.
A balanced diet can reduce the amount of cadmium taken into the body from food and drink.
Is there a medical test to show whether I've been exposed to cadmium?
Tests are available in some medical laboratories that measure cadmium in blood, urine, hair, or nails. Blood levels show recent exposure to cadmium, and urine levels show both recent and earlier exposure. The reliability of tests for cadmium levels in hair or nails is unknown.
Has the federal government made recommendations to protect human health?
The EPA has set a limit of 5 parts of cadmium per billion parts of drinking water (5 ppb). EPA doesn't allow cadmium in pesticides.
The Food and Drug Administration (FDA) limits the amount of cadmium in food colors to 15 parts per million (15 ppm).
The Occupational Safety and Health Administration (OSHA) limits workplace air to 100 micrograms cadmium per cubic meter (100 µg/m³) as cadmium fumes and 200 µg cadmium/m³ as cadmium dust.
Agency for Toxic Substances and Disease Registry
For more information, contact:
 

Agency for Toxic Substances and Disease Registry
Division of Toxicology
1600 Clifton Road NE, Mailstop F-32
Atlanta, GA 30333
Phone: 1-888-42-ATSDR (1-888-422-8737)
FAX: (770)-488-4178
Email: ATSDRIC@cdc.gov

 

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Heavy Metal Poisoning Panel 1&2

Preparation for this test requires to avoid seafood & red wine 72 hours prior to collection.

Definition

Heavy metal poisoning is the toxic accumulation of heavy metals in the soft tissues of the body.

Description

Heavy metals are chemical elements that have a specific gravity (a measure of density) at least five times that of water. The heavy metals most often implicated in human poisoning are lead, mercury, arsenic, and cadmium. Some heavy metals, such as zinc, copper, chromium, iron, and manganese, are required by the body in small amounts, but these same elements can be toxic in larger quantities.

Heavy metals may enter the body in food, water, or air, or by absorption through the skin. Once in the body, they compete with and displace essential minerals such as zinc, copper, magnesium, and calcium, and interfere with organ system function. People may come in contact with heavy metals in industrial work, pharmaceutical manufacturing, and agriculture. Children may be poisoned as a result of playing in contaminated soil.

Causes and symptoms

Symptoms will vary, depending on the nature and the quantity of the heavy metal ingested. Patients may complain of nausea, vomiting, diarrhea, stomach pain, headache, sweating, and a metallic taste in the mouth. Depending on the metal, there may be blue-black lines in the gum tissues. In severe cases, patients exhibit obvious impairment of cognitive, motor, and language skills. The expression "mad as a hatter" comes from the mercury poisoning prevalent in 17th century France among hat makers who soaked animal hides in a solution of mercuric nitrate to soften the hair.

Diagnosis

Heavy metal poisoning may be detected using blood and urine tests, hair and tissue analysis, or x ray.

Lead
 

Lead poisoning can cause severe health problems, including damage to the liver, kidneys, brain, nerves, bones and blood. Children are especially at high risk because they routinely ingest non-food items contaminated with lead. Toxic levels of lead can cause permanent learning disabilities, retardation and even brain damage in young children. Documentation reveals that serious behavioral problems and learning disabilities are seven times more likely to occur in children exposed to low levels of lead over an extended period of time (The New England Journal of Medicine-January 11, 1990). In adults, lead poisoning can cause high blood pressure and reproductive problems. In pregnant women, the fetus is particularly vulnerable to the toxic effects of lead.

Symptoms of lead poisoning can include fatigue, pallor, loss of appetite, irritability, sleep disturbance, sudden behavioral change and developmental regression.

In childhood, blood lead levels above 80 ug/dL generally indicate lead poisoning, however, significantly lower levels (>30 ug/dL) can cause mental retardation and other cognitive and behavioral problems in affected children. The Centers for Disease Control and Prevention considers a blood lead level of 10 ug/dL or higher in children a cause for concern. In adults, symptoms of lead poisoning are usually seen when blood lead levels exceed 80 ug/dL for a number of weeks.

Mercury

Mercury is an extremely toxic element, however only occasional poisoning cases have been reported. It has been used in the past as the active ingredient in ointments, parasiticidals, antiseptics, disinfectants, diuretics and fungicides. Mercury can be a source of environmental contamination when present in seed dressing fungicides, anti-slime fungicides in pulp and paper industries, by-products of burning coal, mine tailings and wastes from chlorine-alkali industries. Whatever the source, mercury finds its way into water sources and accumulates in fish and fish-eating animals. Inorganic mercury which enters a water source is readily converted to methyl mercury by aquatic microorganisms and accumulates in the tissues of fish.
Ingested mercury is rapidly absorbed by the intestinal tract and stored in the kidney and liver. Once absorbed, mercury is slowly eliminated in the urine, feces, saliva, sweat and milk.

Depending upon the amount of mercury ingested, the clinical signs can either be acute or chronic. Ingestion of large amounts of mercury results in almost immediate death due to heart attack. Symptoms of acute poisoning include severe abdominal pains, vomiting and diarrhea. The intestinal mucosa is destroyed and if one survives this first stage, hemorrhagic gastroenteritis is followed by ulcerative colitis with destruction of the kidney tubules. Chronic exposure results in soreness, swelling, bleeding and ulceration of the gums, tongue and oral mucosa with anemia, edema, and body wasting ending in death. Chronic mercury poisoning may be accompanied by mental disturbances due to degeneration of nerve tracts and may result in blindness, weakness, lack of coordination and coma.
Blood levels of mercury should not exceed 3.6 ug/dL, while urine levels should not exceed 15 ug/dL. Symptoms of mercury poisoning may be seen when mercury levels exceed 20 ug/dL in blood and 60 ug/dL in urine. Mercury levels in hair may be used to gauge the severity of chronic mercury exposure.

Arsenic   

Arsenic occurs naturally in the environment as an element of the earth’s crust. Arsenic is combined with other elements such as oxygen, chlorine, and sulfur to form inorganic arsenic compounds. Exposure to higher-than-average levels of arsenic occurs mainly in workplaces, near or in hazardous waste sites, and areas with high levels naturally occurring in soil, rocks, and water. Exposure to arsenic at low levels for extended periods of time can cause a discoloration of the skin and the appearance of small corns or warts. Exposure to high levels of arsenic can cause death.
Since arsenic is rapidly cleared from the blood, blood arsenic levels may not be very useful in diagnosis. Arsenic in the urine (measured in a 24-hour collection following 48 hours without eating seafood) may exceed 50 ug/dL in people with arsenic poisoning. If acute arsenic poisoning is suspected, an x ray may reveal ingested arsenic in the abdomen (since arsenic is opaque to x rays). Arsenic may also be detected in the hair and nails for months following exposure.

Cadmium 

Cadmium is an extremely toxic metal commonly found in industrial workplaces, particularly where any ore is being processed or smelted. Due to its low Permissible Exposure Limit (PEL), overexposures may occur even in situations where trace quantities of cadmium are found in the parent ore or smelter dust. Cadmium is used extensively in electroplating, although the nature of the operation does not generally lead to overexposures. Several deaths from acute exposure have occurred among welders who have unsuspectingly welded on cadmium-containing alloys or working with silver solders. Cadmium is also found in industrial paints and may represent a hazard when sprayed. Operations involving removal of cadmium paints by scraping or blasting may similarly pose a significant hazard. Cadmium is also present in the manufacture of some types of batteries. Cadmium emits a characteristic brown fume (CdO) upon heating, which is relatively non-irritating, and thus does not alarm the exposed individual.
Cadmium toxicity is generally indicated when urine levels exceed 10 ug/dL of creatinine and blood levels exceed 5 ug/dL.

Treatment

The treatment for most heavy metal poisoning is chelation therapy. A chelating agent specific to the metal involved is given either orally, intramuscularly, or intravenously. The three most common chelating agents are calcium disodium edetate, dimercaprol (BAL), and penicillamine. The chelating agent encircles and binds to the metal in the body's tissues, forming a complex; that complex is then released from the tissue to travel in the bloodstream. The complex is filtered out of the blood by the kidneys and excreted in the urine. This process may be lengthy and painful, and typically requires hospitalization. Chelation therapy is effective in treating lead, mercury, and arsenic poisoning, but is not useful in treating cadmium poisoning. To date, no treatment has been proven effective for cadmium poisoning.

In cases of acute mercury or arsenic ingestion, vomiting may be induced. Washing out the stomach (gastric lavage) may also be useful. The patient may also require treatment such as intravenous fluids for complications of poisoning such as shock, anemia, and kidney failure.

Prognosis

The chelation process can only halt further effects of the poisoning; it cannot reverse neurological damage already sustained.

Prevention

Because exposure to heavy metals is often an occupational hazard, protective clothing and respirators should be provided and worn on the job. Protective clothing should then be left at the work site and not worn home, where it could carry toxic dust to family members. Industries are urged to reduce or replace the heavy metals in their processes wherever possible. Exposure to environmental sources of lead, including lead-based paints, plumbing fixtures, vehicle exhaust, and contaminated soil, should be reduced or eliminated.

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TOXIC ELEMENT EXPOSURE - HAIR TESTING

Hair is an excretory tissue for essential, nonessential and potentially toxic elements. In general, the amount of an element that is irreversibly incorporated into growing hair is proportional to the level of the element in other body tissues. Therefore, hair elements analysis provides an indirect screening test for physiological excess, deficiency or mal distribution of elements in the body. Clinical research indicates that hair levels of specific elements, particularly potentially toxic elements such as cadmium, mercury, lead and arsenic, are highly correlated with pathological disorders. For such elements, levels in hair may be more indicative of body stores than the levels in blood and urine.

All screening tests have limitations that must be taken into consideration. The correlation between hair element levels and physiological disorders is determined by numerous factors. Individual variability and compensatory mechanisms are major factors that affect the relationship between the distribution of elements in hair and symptoms and pathological conditions. It is also very important to keep in mind that scalp hair is vulnerable to external contamination of elements by exposure to hair treatments and products. Likewise, some hair treatments (e.g. permanent solutions, dyes, and bleach) can strip hair of endogenously acquired elements and result in false low values. Careful consideration of the limitations must be made in the interpretation of results of hair analysis. The data provided should be considered in conjunction with symptoms, diet analysis, occupation and lifestyle, physical examination and the results of other analytical laboratory tests.

Pubic hair and scalp hair are very different tissues with respect to protein and chemical composition, and rate of growth. The levels of most nutrients elements in pubic and scalp hair for a given individual are typically quite different. Although we do have reference ranges for nutrient elements in pubic hair specimens, there is a lack of clinical data to support sound interpretation at this time. For the potentially toxic elements, however, there appears to be good correlation between scalp and pubic hair. Some clinicians utilize pubic hair for toxic element, (a) to confirm results from scalp hair, and/or (b) when scalp hair has been recently treated with dye or permanent and bleaching reagents.

Toxic Elements Exposure Report

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What is childhood lead poisoning?
Childhood lead poisoning is defined by the Centers for Disease Control and Prevention as a blood lead level of 10 micrograms per deciliter (ug/dL) or above.
The long-term effects of childhood lead poisoning may include slow development of the child, reduced Intelligence Quotient (IQ), learning disabilities, hearing loss, reduced height and hyperactivity.

Who gets childhood lead poisoning?
All children are at risk for lead poisoning, though children living in older housing and in poverty are at the highest risk; these children should be screened more often, starting at an early age. In Virginia, children from 6 to 72 months of age are being targeted for screening efforts.
 

How does a child develop lead poisoning?
Lead may be found anywhere in the environment, but paint that contains lead is the biggest source for childhood lead poisoning. Children who eat paint chips or breathe dust from flaking or peeling lead-based paint are the most likely to develop a problem. Children may also develop high blood lead levels by drinking water contaminated with lead that may be in the plumbing system or by being exposed to contaminated soil or other lead hazards.
 

What are the symptoms?
Most children who have lead poisoning do not have any symptoms. Symptoms that do appear, such as stomach ache, poor appetite, and irritability, are often confused with other childhood illnesses. Very severe lead exposure (levels greater than 80 ug/dL) can cause coma, convulsions and even death.
 

How soon do symptoms appear?
This depends on the level of lead in the blood, but again, symptoms do not always occur with childhood lead poisoning.
 

How is lead poisoning detected?
The only way to find the problem is to test the blood. This is why it is important to test young children. Children who are at high risk for lead poisoning should be tested at 6 months of age. Other children should be tested at age 12-15 months.

Whole blood is required for screening. As with all other clinical tests, proper specimen collection is critical.
Collection via a finger stick procedure requires extreme care to ensure an uncontaminated and representative specimen is obtained. Such capillary samples may be useful for screening children up to 16 years old. The CDC does not recommend filter paper collection.

The Centers for Disease Control and Prevention recommends the following test schedule for children with elevated blood lead levels on a screening test.

Venipuncture ( obtaining blood through a vein) provides the most reliable specimen and should be used for confirmation of abnormal finger stick results, clinical follow-up and occupational monitoring. Specimens should be collected in specimen tubes or plastic micro collection devices proven to be lead or trace element "free".
 

Why Lead and Zinc Protoporhyrins (ZPP)

Only two common reasons are known to cause elevated zinc protoporphyrin levels. Iron deficiency or elevated lead burden. Rare genetic disorders may cause elevated ZPP.

The detection of ZPP levels in blood has been shown to be an effective method of screening for chronic lead poisoning. In a subject with an appreciable lead burden, the lead ions interfere with the normal synthesis of hemoglobin by preventing the usual insertion of iron into protoporphyrin to make heme part of hemoglobin (which is heme plus a protein and which is the carrier of oxygen in the blood. The body contains 750 grams (1.6 pounds) of hemoglobin which is replaced every 120 days.
.
As a result of the lead ions interfering with the normal synthesis of hemoglobin, zinc is incorporated into the protoporphyrin and the resulting ZPP remains in the hemoglobin and the red blood cell for the life of the cell.
Chronically lead exposed children and adults with elevated blood lead levels always have high ZPP readings.
Erythrocyte protoporphyrin and whole blood lead levels are probably more sensitive indicators of excessive lead exposure
 

If a case is found, should family members be tested?       
A case of childhood lead poisoning indicates an environmental source of lead, often in the home. Brothers and sisters through age 6 should be tested. If the source stems from a renovation project, parents and older siblings may need a medical history taken to check for signs of acute exposure. If the source is found to be a day care center, other children using that facility should be tested.
 

How is childhood lead poisoning treated?
High levels of lead in the blood should be removed by a treatment called chelation. Chelation is needed at blood lead levels of 45 ug/dL and above. Doctors may decide to use this therapy at lower blood lead levels, too, depending on the child's age, housing situation and clinical signs and symptoms. While chelation used to require a hospital stay, a new medication called succimer can be taken by mouth and, therefore, used on an outpatient basis. Hospitalization may be needed in some cases.

Can a lead poisoned child return home?
If a child is to receive chelation therapy as an outpatient and the home is found to be the source of the lead, the child should live somewhere else until the source of the lead is removed from the home.

What can be done to prevent childhood lead poisoning?
Keeping the home clean, eating a good diet, and washing hands can help prevent lead poisoning. Adults can check the home for potential danger areas, looking for flaking paint, crumbling plaster, indoor dust and outdoor dirt that may have lead in it. Any peeling paint should be removed and the paint chips swept away. Children should not be present when scraping or cleaning up paint chips. Dust should be kept to a minimum by damp mopping and using a wet cloth to clean walls, window sills, and other surfaces. Painted wood should not be burned for heating.

Toxic metals, which include "heavy metals," are individual metals and metal compounds that negatively affect the health of people. Some semi-metallic elements (for example, arsenic and selenium) are considered in this Safety and Health Topic due to their toxicity. At trace levels, many of these elements are necessary to support life. However, at elevated levels they become toxic, may build up in biological systems, and become a significant health hazard.
 

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Water Contaminants

There is no such thing as naturally pure water.  In nature, all water contains some impurities.  As water flows in streams, sits in lakes, and filters through layers of soil and rock in the ground, it dissolves or absorbs the substances that it touches.  Some of these substances are harmless.  In fact, some people prefer mineral water precisely because minerals give it an appealing taste.  However, at certain levels minerals, just like man-made chemicals, are considered contaminants that can make water unpalatable or even unsafe. 

Some contaminants come from erosion of natural rock formations.  Other contaminants are substances discharged from factories, applied to farmlands, or used by consumers in their homes and yards.  Sources of contaminants might be in your neighborhood or might be many miles away.  Your local water quality report tells which contaminants are in your drinking water, the levels at which they were found, and the actual or likely source of each contaminant. 

Some ground water systems have established wellhead protection programs to prevent substances from contaminating their wells.  Similarly, some surface water systems protect the watershed around their reservoir to prevent contamination.  Right now, states and water suppliers are working systematically to assess every source of drinking water and to identify potential sources of contaminants.  This process will help communities to protect their drinking water supplies from contamination, and a summary of the results will be in future water quality reports.