Skip to Main Content View Text-Only

Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

1120 SW 5th Avenue, Suite 1000, Portland, OR 97204

Table of Contents
Metals
The descriptions below provide general information for each topic. Click on each topic to get subwatershed specific descriptions.

Arsenic
Arsenic is a naturally occurring element found in soil and rock. Inorganic forms of arsenic are used for wood preservation, while the organic forms have been used as crop pesticides. Human exposure to arsenic is from direct ingestion of exposed food or water or breathing contaminated air. Exposure can also come from breathing sawdust or burning smoke from wood treated with arsenic. Exposure to low levels of arsenic can cause nausea, abnormal heart rhythm, and damage to blood vessels; high level exposure can cause death. The EPA has determined that inorganic arsenic is a human carcinogen with links to lung, skin, bladder, liver, kidney, and prostate cancer.

The current water quality criteria for total arsenic, which are also indicated in (Table 3), are:
-Acute criteria for protection of aquatic life: 360 ug/L
-Chronic criteria for protection of aquatic life: 190 ug/L
-Water and fish ingestion criteria for protection of human health: 2.2 ng/L
-Fish consumption criteria for protection of human health: 17.5 ng/L
-Drinking water Maximum Contaminant Level: 0.05 mg/L



Cadmium
Cadmium is a naturally occurring element in soil and rock and is extracted during production of other metals like lead, copper and zinc. Wear of automobile tires can be a source of cadmium in urban areas. Cadmium also enters the air from mining, industry, and burning of coal. Cadmium enters the soil and water by atmospheric deposition, industrial spills and disposed waste. Cadmium is taken up from soil and sediments by plants. Animals are exposed to cadmium by consuming the contaminated plants. Because it does not easily degrade, it remains in the plants and animals for a long time and with continued intake, can accumulate over a long exposure period. Humans are exposed to cadmium by consuming contaminated plants, animals or fish, as well as by breathing in contaminated air or drinking cadmium containing water. Long-term exposure to low levels of cadmium in air, food or water can cause an accumulation of cadmium in the kidneys and lead to kidney disease. The Department of Health and Human Services had determined that cadmium “may reasonably be anticipated to be carcinogenic” however; insufficient data has been gathered at this point to make a definite link to cancer.

The current water quality criteria for total cadmium, which are also indicated in (Table 3), are as follows:

Acute criteria for protection of aquatic life: 1.8 ug/L*
Chronic criteria for protection of aquatic life: 0.066 ug/L*
Water and fish ingestion criteria for protection of human health: 10 ug/L
Drinking water Maximum Contaminant Level: 0.010 mg/L

*Criteria are hardness-dependent; 50 mg/L hardness assumed.


Chromium
Chromium is a naturally occurring element found in rocks, animals, plants, and in volcanic dust and gases. It is present in the atmosphere in many different forms with some forms being essential for the body to use sugars, proteins and fats and others being carcinogens. Exhaust from diesel-fueled vehicles can be a source of chromium in urban environments. Chromium of various forms is used for making steel, chrome plating, pigments, leather tanning and wood preservation. Human exposure comes from eating contaminated food, drinking contaminated water (predominantly well water), or breathing contaminated air in industrial areas. Human health effects of breathing certain forms of chromium are nose irritation or bleeding, ulcers and holes in the nasal septum and effects of ingestion of certain from are stomach ulcers, kidney and liver damage and even death. The EPA has classified certain forms of chromium as human carcinogens.

The current water quality criteria for total chromium, which are also indicated in (Table 3), are as follows:

Acute criteria for protection of aquatic life16 ug/L
Chronic criteria for protection of aquatic life: 11 ug/L
Water and fish ingestion criteria for protection of human health: 50 ug/L
Drinking water Maximum Contaminant Level: 0.05 mg/L



Copper
Copper is a metal that occurs naturally in rocks, water, and air, as well as in plant and animals. It is used in the U.S. penny, electrical wiring, and in water pipes. Copper is the primary metal component of brake pads and is present in exhaust of diesel-fueled vehicles. Copper compounds are also commonly used in treating mildew, for preservation of wood, leather and fabrics, as a water additive to control algae in swimming pools, and as a root killer in residential plumbing applications. Copper can enter the environment when rainfall runs off roofs, gutters, and downspouts made with copper. Human exposure can come from swimming in copper treated swimming pools, breathing air containing copper released from combustion of fossil fuels, or treated wood as well as breathing air from an industrial location which works with copper, or eating or drinking food or water contaminated with copper. Some amounts of copper are essential for good human health, however, long term exposure to high levels of it in the air can irritate the nose, mouth and eyes, as well as cause headaches, dizziness ad nausea. Drinking high levels of copper can lead to diarrhea and vomiting and even liver and kidney damage. Not enough data has been collected to determine if copper is a carcinogen, therefore, the EPA has not classified it for carcinogenicity. Copper is highly toxic to some aquatic species.

The current water quality criteria for total copper, which are also indicated in (Table 3), are as follows:

Acute criteria for protection of aquatic life: 9.2 ug/L*
Chronic criteria for protection of aquatic life: 6.5 ug/L*

*Criteria are hardness-dependent; 50 mg/L hardness assumed.


Iron
Iron is a relatively abundant, naturally occurring element in the environment. It is used in many industrial and manufacturing processes. In urban environments, sources of iron include rust from automobile bodies, steel highway structures such as guard rails, and moving engine parts. High iron concentrations can cause staining of riverbanks and flood plains.

The current water quality criteria for total iron, which are also indicated in (Table 3), are as follows:

Chronic criteria for protection of aquatic life: 1,000 ug/L Water and fish ingestion criteria for protection of human health: 0.3 mg/L


Lead
Lead is a metal found in small amounts in the earth’s crust. Much of the lead in air and water environments come from human activities such as burning fossil fuels, mining, and manufacturing. In urban areas, primary sources of lead can be transportation and construction related. Lead is used in automobile brake pads, filler material in tires, balancing weights for tires, and is present in diesel fuel. Lead enters the environment in fine particulate form from these transportation-related sources. Pipes, pipe solder, and lead-based paints can be sources of lead. Lead enters surface waters via runoff from impervious surfaces where deposition of particulates has occurred and through runoff from building walls coated with lead-based paint. Wet deposition (rain collecting lead particles from the air) can also occur. Human exposure comes from contact with lead-based paints, eating food or drinking water containing lead, or from occupational exposure. Lead can affect almost every organ and system in the body, the most sensitive being the nervous system. It can decrease reaction time, cause memory loss, and damage kidneys and damage the male reproductive system. The Department of Health and Human Services determined lead may “reasonably be anticipated” to be a carcinogen, however more data is needed for a conclusive determination.

The current water quality criteria for total lead, which are also indicated in (Table 3), are as follows:

Acute criteria for protection of aquatic life: 34 ug/L*
Chronic criteria for protection of aquatic life: 1.3 ug/L*
Water and fish ingestion criteria for protection of human health: 50 ug/L
Drinking water Maximum Contaminant Level: 0.05 mg/L

*Criteria are hardness-dependent; 50 mg/L hardness assumed.


Manganese
MManganese is a naturally occurring element in soil and rock. Manganese exists naturally in rivers and lakes. There are many different manganese compounds that have a wide variety of uses from pesticides to fuel additives to healthy ingredients in breakfast cereal. Moving automobile engine parts can be a source of manganese in urban areas. Manganese can enter the air from power plants, industry (coke ovens, steel plants) and mining operations. Long-term exposure to elevated manganese concentrations can cause mental and emotional disturbances and well as slow and clumsy body movements and sexual dysfunction. No human cancer data is available for manganese yet; therefore, the EPA had determined that it is not classifiable as a human carcinogen.

The current water quality criteria for total manganese, which are also indicated in (Table 3), are as follows:

Water and fish ingestion criteria for protection of human health: 50 ug/L
Fish consumption criteria for protection of human health: 100 ug/L


Mercury
Mercury is a naturally occurring metal than appears in the environment in many different forms. It enters the environment from natural deposits as well as from mining and coal burning operations, manufacturing plants, and municipal wastewater. Household products such as thermometers, thermostats, and light switches can be a source of mercury. Exhaust from diesel-fueled vehicles is also a source of mercury. Mercury builds up in the fatty tissue of fish and will continue to accumulate with continued exposure. Mercury will bioaccumulate at increasing concentrations up the food chain as larger animals feed on the smaller fish. Human exposure occurs from consumption of contaminated fish or other animals as well as releases of mercury from dental work and from breathing contaminated workplace air. Exposure to high levels of mercury can cause permanent brain and kidney damage as well as damage a developing fetus. There has not been enough data collected on mercury to determine if it is a carcinogen, however, the EPA had determined that it is a possible carcinogen.

The current water quality criteria for total mercury, which are also indicated in (Table 3), are as follows:

Acute criteria for protection of aquatic life: 2.4 ug/L
Chronic criteria for protection of aquatic life: 0.012 ug/L
Water and fish ingestion criteria for protection of human health: 144 ng/L
Fish consumption criteria for protection of human health: 146 ng/L
Drinking water Maximum Contaminant Level: 0.002 mg/L



Zinc
Zinc is one of the most common elements. Some level of zinc is found in all food products as well as in all watershed systems. There are some natural releases of zinc to the environment but most is released from human activities such as coal burning. Wear of automobile brake pads, wear of tires, motor oil, grease, and exhaust from diesel-fueled vehicles are transportation-related sources of zinc in urban environments. Human exposure comes from eating foods and drinking water containing zinc, from drinking beverages stored in metal containers coated with zinc, from breathing it from the air surrounding manufacturing sites, or from eating zinc vitamin supplements. Although zinc is essential to good health, excessive zinc exposure can cause nausea, vomiting and over the long-term anemia and pancreas damage. Insufficient data has been collected on the possible carcinogenic effects of zinc, therefore the EPA has not classified zinc for carcinogenicity at this time.

The current water quality criteria for total zinc, which are also indicated in (Table 3), are as follows:

Acute criteria for protection of aquatic life: 65 ug/L*
Chronic criteria for protection of aquatic life: 59 ug/L*

*Criteria are hardness-dependent; 50 mg/L hardness assumed.

Maps & Files

Questions & Comments
If you have any questions or comments on our web site, please contact our webmaster.

Heartbleed Security Notice

A serious security vulnerability known as "Heartbleed" was recently discovered in OpenSSL, a popular software library commonly used by many websites on the internet to encrypt communication between a user's computer and a web server.

PortlandOregon.gov is NOT affected by this vulnerability as it does not use the OpenSSL software library. Please rest assured we are dedicated to protecting your security on this website.