Aluminum is one of the most common metals found on earth. It is always found combined with other minerals and rocks. Aluminum has a wide variety of industrial and home uses. Aluminum compounds are used as food containers, food additives, medicines, and treatments for drinking water.

How Might I Be Exposed to Aluminum?
Since aluminum is found everywhere on earth, everyone is exposed to low levels of aluminum from food, air, and water. In general, most (about 95%) of exposure to aluminum occurs from food. About 5% of exposure to aluminum comes from water. Very little of the aluminum that is ingested or breathed in is actually absorbed into the body.

Possible routes of aluminum exposure are:

• The daily intake of aluminum from food is about 5-20 mg per day. Potatoes, spinach, and tea, and processed foods with aluminum additives have more aluminum than other foods.
• Aluminum is found in medications such as antacids and analgesics. People taking such medications may be ingesting up to 5 grams of aluminum per day.
• Aluminum levels in the air vary by region. In remote places such as Antarctica the levels are around .0005µg/m³, in industrial areas the levels are around 1 µg/m3. Aluminum dust is sometimes present in higher concentrations in the workplace.
• In drinking water levels of aluminum also vary by region.
• Very little enters your body from aluminum cooking utensils.

How Can Aluminum Affect My Health?
Exposure to aluminum from food, air, water, or skin contact at concentrations experienced by most people is not thought to harm your health. Very high levels of aluminum may be harmful. Exposure to high levels of aluminum affects breathing, the nervous system, and bones.  Aluminum has been linked to Alzheimer's disease because those patients have high levels of aluminum in their brains. We do not know whether aluminum causes the disease or whether the buildup of aluminum happens to people who already have the disease.

What Regulations Protect Human Health?
The Environmental Protection Agency (EPA) has established secondary (voluntary) limits on the level of aluminum in drinking water at 2 parts per million. The California Department of Health Services (CDHS) has established a mandatory limit of aluminum in drinking water of 1 part per million. The levels of aluminum found in drinking water supplied by San Francisco Public Utilities (SFPUC) are less than 0.05 parts per million, which is well below the regulatory limit of 1 part per million.

Arsenic is a naturally occurring element in rocks, soils, and the waters in contact with them.  Arsenic enters water supplies from natural deposits in the earth and from industrial and agricultural pollution.  Non-iron smelting, electronics manufacture, wood preservation, arsenic production, glass production, and production or application of pesticides that contain arsenic, are activities that can lead to arsenic pollution. Arsenic concentrations are generally highest in groundwater and in water polluted by acid mine drainage. Surface water concentrations are generally low, but may also be at levels of regulatory concern. 

How Might I Be Exposed to Arsenic?
Because trace amounts of arsenic are found in most food, food is the main route of exposure for most people. Non-smokers, who do not work in industries where they are exposed to high levels of arsenic in the air, inhale about 1 µg of arsenic per day. Smokers who smoke 40 cigarettes per day inhale about 10 µg of arsenic per day. Children can be exposed to arsenic by eating contaminated soil, and by playing on jungle gyms made from wood treated with arsenic.

Exposure to arsenic can occur through:

• Eating contaminated food or soil
• Drinking contaminated water
• Smoking cigarettes
• Breathing contaminated air at occupational or industrial sites
• Breathing sawdust or inhaling smoke from wood containing arsenic

How Can Arsenic Affect My Health?
Arsenic occurs in several different states and the severity of health effects depends on the type of arsenic. In general inorganic arsenic is more toxic that organic arsenic. In large doses arsenic can lead to multiple organ failure and death. Long-term exposure to smaller amounts of arsenic has been shown to cause skin and blood vessel disorders, a metallic taste in the mouth, and bladder, lung, kidney, and skin cancer.

What Regulations Protect Human Health?
The EPA has set a limit for arsenic in drinking water of 10 parts per billion or lower. The CDHS has set a standard of 50 parts per billion. The CDHS Office of Environmental Health Hazard Assessment has set a public health goal for arsenic in drinking water of 0.004 parts arsenic per billion parts water. The SFPUC has tested its drinking water for the presence of arsenic.  Arsenic levels of between 2 and less than 2 parts per billion have been detected in SFPUC’s regular water supply. During severe drought conditions the SFPUC may need to use its emergency water supply from the South Bay Aqueduct. Water from this source tested in the past has had a maximum arsenic level of 13 parts per billion and an average level of 4 parts per billion. SFPUC is working on a plan for treating this water if it becomes necessary to use it.

Copper

Copper is a common reddish metal that can be found in rocks, soil, water, and air. Copper can be easily molded or shaped. U.S. pennies, electrical wiring, and some water pipes contain copper. It is also found in many mixtures of metals, called alloys, such as brass and bronze.

How Might I Be Exposed to Copper?
Copper is common in the environment. You may be exposed to copper by breathing air, drinking water, eating food, and by skin contact with soil, water, and other copper-containing substances. People are primarily exposed to copper from food.

Exposure to copper can occur through:

• Ingesting water or food (especially organ meats, seafood, nuts,  and seeds), that contains copper
• Having skin contact with something containing copper
• Inhaling air that contains copper
• Using some types of fungicides

How Can Copper Affect My Health?
Copper is an essential mineral for humans and other organisms. The FDA recommends a daily intake of 2 mg of copper. Not ingesting enough copper can lead to anemia, osteoporosis, abnormal glucose tolerance, elevated cholesterol levels, arthritis, heart problems, loss of skin color and neurological problems. Ingesting too much copper can also lead to health problems. Ingesting large amounts of copper all at once can lead to nausea, vomiting, stomach pain, diarrhea, and kidney and liver problems. Long term exposure to excess copper can also lead to liver problems. Copper is not known to cause cancer.

What Regulations Protect Human Health?
The EPA has determined that drinking water should not contain more than 1.3 parts per million of copper. CDHS has set a standard of 1 part per million. The action level for copper in tap water in San Francisco is 1.3 parts per million. The SFPUC has tested copper levels in tap water from 53 San Francisco households and found that the levels of copper in tap water ranged from .011 to .35 parts per million.

Chromium is a metallic element, found in three states; chromium (0), chromium (VI), and chromium (III).  Trivalent chromium, or chromium (III), is the naturally occurring state, and is an essential nutrient. Chromium (0) and hexavalent chromium, also known as chromium (VI), form as a byproducts of the manufacture of stainless and hard-alloy steels and pigments.  Chromium (VI) is the toxic and carcinogenic form of chromium.

How Might I Be Exposed to Chromium?
Chromium (III) is naturally occurring, and is found at low levels in food such as brewer's yeast, beef, liver, chicken, eggs, wheat germ, green peppers, apples, bananas, and spinach. Hexavalent chromium is found in deep aquifers, and may also enter drinking water, soil, and air through the discharges of dye, paint pigments, wood preservatives, chrome plating liquid wastes, or through leaching from hazardous waste sites.  Concentrations of chromium (VI) in air vary depending on whether measurements are taken at a remote or urbanized location. Chromium (VI) poses the biggest risk to health when it is inhaled.

Exposure to chromium can occur through:

• Ingesting food or water contaminated with chromium
• Inhaling air that is polluted by chromium
• Skin contact with chromiumHow Can Chromium Affect My Health?

Chromium (III) is an essential trace nutrient, with an estimated daily requirement of 25 to 35 micrograms per day. Chromium (VI) ingested in low amounts is converted to chromium (III) in the stomach. However, ingesting large amounts of chromium (VI) can cause health problems such as stomach ulcers, and kidney and liver damage. Skin exposure to chromium (VI) can result in allergic reactions. Inhalation of chromium (VI) can cause ulcers and holes to appear in parts of the nose and has been linked to lung cancer.

What Regulations Protect Human Health?
State and federal drinking water standards are set for total chromium (a combination of chromium III and VI).   The EPA maximum contaminant level goal for total chromium is 100 parts of total chromium per billion parts of water.  The CDHS has set a standard for total chromium at 50 parts per billion parts water.  The SFPUC has tested its drinking water for the presence of chromium and chromium (VI).  No detectable levels of chromium or chromium (VI) have been found in the SFPUC source or treated water. 

Fluoride

Fluoride is the general name for a group of compounds made with fluorine. Fluorine is an element but because it is very reactive it is rarely found in its elemental form. It often reacts with other substances to form fluoride. Sodium fluoride is often added to toothpaste or mouth rinse to help prevent cavities. Other fluorides such as hydrogen fluoride are used in manufacturing applications. Many communities add fluorides to the drinking water to help prevent cavities.  Some skin medicines and cancer treatment drugs also contain fluorides.

How Might I Be Exposed to Fluoride?
Fluorides are common in the environment. Everybody is exposed to some levels of fluoride from air, water, and food. Fluorides occur in air as a result of natural causes, such as volcanoes, and as a result of industrial activity. Water often contains fluorides or is supplemented with fluorides. Fish contain higher levels of fluorides, as does food prepared with fluoridated water.

Exposure to fluorides can occur through:

• Breathing workplace air where fluorides are used or released
• Eating or soil with high fluoride levels
• Eating toothpaste that contains fluorides
• Drinking water that contains fluorides

How Can Fluorides Affect My Health?
Daily intake of 1 to 3 mg of sodium fluoride helps reduce tooth cavities, but high levels can harm your health. In children whose teeth are forming, high fluoride exposure can cause dental fluorosis. In adults, high fluoride intake (by ingestion or inhalation) over a long time can lead to weight loss, anemia, discoloration of teeth, and skeletal fluorosis. Large doses ingested or inhaled all at once can cause nausea, vomiting, stomach pain, heart problems, lung, kidney, and liver damage, irritation to eyes and throat, and death.

What Regulations Protect Human Health?
The EPA sets a maximum fluoride amount of 4 parts per million. The CDHS has specific fluoridation requirements for utilities that vary according to the average temperature in the area where the utility is located. For SFPUC the requirement is for a fluoride level of 1 part per million. SFPUC water has a natural fluoride level of about 0.2 parts per million. In 2002, SFPUC treated water in San Francisco had an average fluoride level of 1 part per million.

For Further information about fluoride:

Lead

Lead is a naturally occurring bluish-gray metal found in small amounts in the earth's crust. Lead can be found in all parts of our environment. Human activities like mining, manufacturing, and the burning of fossil fuels have increased environmental lead levels. In general, industrialized urban areas have higher levels of lead in the air, soil, and water than more remote locations.How

Might I Be Exposed to Lead?
Exposure to lead can occur though inhalation of contaminated air, or ingestion of contaminated soil, food, medication, water, or other objects. Routes of highest exposure vary among different populations, and locations. In areas where there are high amounts of lead in the air, the highest exposure to lead may occur through inhalation. Children living in homes built before 1978 are at highest risk for lead exposure through eating lead based paint chips, or dust and dirt covered in lead. People who live in homes with lead or brass plumbing may be most exposed to lead through their drinking water. Food can become contaminated with lead during the manufacturing process. People who work in industries that use lead may be exposed to high lead levels at work. Family members of these workers may also be exposed to elevated levels of lead if the workers bring home clothes or equipment that contains lead dust. Other exposures can occur through lead glazed pottery or glass.

Lead exposure can occur through:

• Eating contaminated food, paint chips, soil, or dust
• Breathing in air or dust that contains lead particles
• Drinking water that comes from lead or brass plumbing
• Smoking
• Cooking in containers that are glazed with lead
• Breathing fumes or ingesting lead from hobbies or industries that use lead

How Can Lead Affect My Health?
Lead can affect almost every organ and system in your body. The most sensitive is the central nervous system, particularly in children. Children are especially vulnerable to the effects of lead because they often eat paint chips, dirt, or toys that can be contaminated with lead. When children ingest lead they absorb more of the lead into their bodies than adults do and the lead can reach their nervous system and brain more easily than in adults. Lead can also cause kidney, liver, reproductive, circulatory, and the immune system damage.

The EPA has set an action level for lead in drinking water at the tap of 15 parts lead per billion parts water or below.  If more than 10% of tap water samples are above the action level, the EPA requires utilities to implement additional water quality monitoring, corrosion control, and public education measures.  SFPUC water consistently has lead levels below the action level.  Because of its good record, SFPUC has been approved by the CDHS to test for lead in tap water every three years.  During the last two testing periods in 2001 and 2004, SFPUC found that the tap water in San Francisco was within the limits of the EPA action level.  Levels can vary between residences due to plumbing differences. 


What Regulations Protect Human Health?
The EPA has set an action level for lead in drinking water at the tap of 15 parts lead per billion parts water or below. If more than 10% of tap water samples are above the action level, the EPA requires utilities to implement additional water quality monitoring, corrosion control, and public education measures. SFPUC water has consistently had lead levels that were below the action level. Because of its good record, SFPUC has been approved by the CDHS to test for lead in tap water every three years. During the last testing period in 2001, SFPUC found that the tap water in San Francisco was within the limits of the EPA action level. Levels can vary between residences due to plumbing differences. The next testing period will occur in Fall 2004.

The CDC recommends that children be routinely screened for lead poisoning. The Childhood Lead Prevention Program, in the San Francisco Department of Public Health provides medically related services for children who have elevated lead blood levels, provides public education, and advocates for policy changes that would reduce children’s exposure to lead. SFPUC offers lead-free faucets to the general public for $10; and at no cost to families in the Women, Infants and Children (WIC) Program. SFPUC also offers no cost tap water testing for WIC families.