WHAT IS ARSENIC?
Arsenic is a naturally occurring semi-metal found on the earth's crust. It is odorless and tasteless. It can be found in organic form, which is harmless to humans, and inorganic form, which can have big health impacts. Hand-washing, bathing, laundry, etc., with water that has high levels of inorganic arsenic do not pose a health risk.
WHY CARE ABOUT ARSENIC?
When exposed to inorganic Arsenic, people experience negative health impacts. The first changes usually observed after long-term exposure to arsenic are discoloration of skin or abnormal growths. Long-term exposure to arsenic has been linked to higher risks of lung, bladder, skin, liver, kidney, nasal passages, and prostate cancer. Other effects include thickening and discoloration of skin, nausea, stomach pain, vomiting, diarrhea, hands and feet numbness, partial paralysis, and blindness. Although ingesting arsenic is a health concern, absorbing arsenic through the skin is minimal.
WHAT IS CADMIUM?
Cadmium is a naturally occurring metal found in low concentrations. Cadmium is used in the manufacturing of batteries, pigments, plastic stabilizers, metal coatings, alloys and electronics. It can also be found in fairly high concentrations in sewage sludge.
WHY CARE ABOUT CADMIUM?
It is a non-essential element which means that it aquatic life doesn't utilize it and is harmed by the metal. It also has been shown to cause toxic effects to the kidneys, bone defects, high blood pressure, and reproductive effects.
WHAT IS CHROMIUM?
Chromium does not naturally occur in nature. Chromium compounds can only be found in waters in trace amounts (meaning that it is only found in small concentrations). The element and its compounds can be discharged in surface water through some industries like paints, metal refineries, and leather tanning.
WHY CARE ABOUT CHROMIUM?
Trivalent chromium is an essential trace element for humans. Together with insulin it removes glucose from blood, and it also plays a vital role in fat metabolism.
However, hexavalent chromium is extremely toxic and is known for its genotoxic carcinogens. It can cause allergic and asthmatic reactions, diarrhea, stomach and intestinal bleeding, cramps, and liver and kidney damage. Hexavalent chromium is mutagenic and toxic effects may be passed on to children through the placenta.
WHAT IS COPPER?
Copper is an abundant trace element that occurs naturally in the Earth’s crust and surface waters. Copper is a great conductor of electricity. Copper is commonly found in aquatic systems as a result of both natural sources like geological deposits, volcanic activity, and erosion of rocks and soils, and anthropogenic sources such as, mining activities, agriculture, metal and electrical manufacturing, sludge from publicly-owned treatment works, pesticide use are a few of the anthropogenic sources contributed to surface waters.
WHY CARE ABOUT COPPER?
Copper is an essential nutrient at low concentrations, however at higher concentrations copper is toxic to aquatic life. It can lead to adverse effects on survival, growth, reproduction as well as alterations of brain function, enzyme activity, blood chemistry, and metabolism.
WHAT IS LEAD?
Lead is a toxic heavy metal that can be found on earth's crust. Lead does not usually naturally occur in drinking water, but it can be present in household plumbing or water service lines and contaminate drinking water through corrosion of plumbing materials.
WHY CARE ABOUT LEAD?
Children have the highest health risk from exposure to lead. Exposure to lead can lead to premature birth, reduce birth weight, delayed physical and mental development in babies and toddlers and cause learning disabilities and slight deficits in attention span in children. Accumulation of lead in adults can cause high blood pressure and kidney problems. Long-term exposure of high levels of lead may also potentially cause anemia, stroke, damage to the nervous system, and cancer.
WHAT IS MERCURY?
Mercury is a naturally occurring, highly toxic metal and potent neurotoxin. It impacts the function and development of the central nervous system in both people and wildlife. Scientists have found alarming levels of mercury accumulation in a wide range of wildlife species, causing dangerous reproductive and neurological problems.
WHY CARE ABOUT MERCURY?
Human activity has significantly increased mercury levels in the environment over the past several centuries. When mercury falls to the earth from the air it builds up in surface water and transforms into methylmercury--a highly potent form of mercury that accumulates in the tissues of wildlife and people. Methylmercury bioaccumulates, which means that it increases in concentration with each step up in the food chain. When people consume large amounts of fish that contain mercury, they may experience neurological and gastrointestinal problems. In severe cases, people may even develop Chisso-Minamata disease.
WHAT IS SELENIUM?
Selenium is a naturally occurring element present in sedimentary rocks, phosphate deposits and soils. Selenium can enter into surface water through weathering and erosion, or it can also be released during mining related activities, coal fired plants, and irrigation for agriculture.
WHY CARE ABOUT SELENIUM?
In small amounts selenium is an essential element for animals, but at higher concentrations is toxic. Like mercury, it bioaccumulates in the aquatic food chain and chronic exposure in fish and aquatic invertebrates can cause larval deformity or mortality. When it combines with hemoglobin, selenium can damage a fish’s respiratory system. Selenium is also toxic to waterfowl and other birds that consume aquatic organisms containing excessive levels of selenium.