Copper is a metal that can be found in environmental waters; it can occur naturally or through human activities. Copper is widely used in electrical equipment, such as wiring and motors, and in plumbing materials, such as household water pipes.
Copper at low doses is not damaging to human health and is an essential nutrient for the human body. However, high levels of copper in the body can cause depression, fatigue and other symptoms. Long-term copper exposure can cause anaemia and damage liver and kidney functions.
Copper in water can be classified as insoluble, dissolved (free and complexed), and total recoverable. All copper in solution is known as dissolved copper, including Cu+ (cuprous) and Cu2+ (cupric) ions and copper complexes such as Cu/EDTA.
Read below to find out why it is necessary to test for copper and to find out some of the latest guidelines and regulations surrounding copper in water.
Copper levels are closely monitored in drinking water networks. An increase in copper levels can indicate there is damage to the pipe network which is either causing leaching of copper from the pipes into the water, or alternatively that there is an ingress of water from somewhere else.
In 1991, the US EPA published the Lead and Copper Rule (LCR) to control lead and copper in drinking water. Since its publication the rule has undergone several revisions. The rule states that action must be taken if copper exceeds 1.3 µg/L in more than 10% of taps sampled. UK regulations, by the DWI, have set a limit for copper in drinking water at 2 µg/L.
Blue-green stains on plumbing fixtures can be an indication of increased levels of copper in the water.
The level of copper in surface and ground water is generally low. Higher levels of copper may get into the environment through mining, farming, manufacturing operations, and municipal or industrial wastewater releases into rivers and lakes. In surface water copper can travel large distances, either suspended on sludge particles or as free ions.
Copper should be monitored in surface and ground water because it can be toxic to aquatic organisms at higher concentrations. Prolonged exposure to high levels of copper can lead to adverse effects on survival of aquatic life.
Industries whose wastewater may contain significant concentrations of copper include mining, ammunition production, and most metal plating and finishing operations. It may occur in simple ionic form or as cyanide, chloride, or ammonia complexes. Because of the effect of copper on aquatic life it should be monitored in wastewater before being discharged.
In pools and spas, copper algaecide is often used to help control the growth of algae. It is used in addition to usual disinfection when there is a large concentration of algae in the pool. Copper algaecides work by disrupting the cellular processes in algae that are essential for survival.
The alkalinity of the water must be determined before adding copper algaecide to the pool or spa. This is important because using a copper algaecide increases alkalinity levels of the water.
Copper is a natural constituent of soil and can be carried into natural water via runoff. In soil copper strongly attaches to organic matter and minerals. It is a vital micronutrient for plants, but excessive concentrations can harm plant life.
Copper can interrupt the activity in soils; it negatively influences the activity of microorganisms and earthworms.