Lead and Copper in Drinking water
Lead is not naturally found in water, but mainly enters drinking water through corroded pipes, plumbing and lead solders. Old brass or chrome plated fittings are a common culprit. Strong tap velocity can also influence the amount of metal ions in water by lifting settled sediment.
Have you noticed the new plastic (PVC) pipes that are continually replacing the old metal cast iron and lead pipes? Changing the material water pipes are made from is a vitally important measure to reduce the amount of lead and copper in water.
Industrial use of lead (eg. battery, paint, alkyl lead manufacture) also contributes to the problem of lead in water, especially when factories do not take corrective measures before discharging waste water.
World-wide, there has been an increased focus on lead and copper in drinking water. In Europe, there is a new EC Directive – 80/778/EEC. In the US, the “Reduction of Lead in Drinking Water Act” became effective from January 2014. This Act is related to the usage of lead pipes, plumbing fittings or fixtures, solder and flux.
In South Africa, the previous standards (SANS 241: 2005) for lead in water were more lenient than international allowable limits. They have been revised in the SANS 241-1: 2011 Drinking Water Standards and are now stricter and in line with international standards.
A Helpful Measure:
If lead piping takes time to be replaced, especially in older houses, water should be allowed to run for 30 – 60 seconds through the system before drinking. This should be done first thing in the morning or when water has not been run for longer than 6 hours. Soft water in coastal regions etc. will allow more metal ions through the water, so extra care should be taken in these areas.
Addition of Phosphates to Water:With the increased focus on the content of lead in drinking water, phosphates are frequently added to to water, to reduce lead and copper levels. Phosphate levels need to be kept under control, as high phosphate levels lead to lower oxygen levels, which really disrupts the entire eco-system.
Why test for Lead and Copper?
Lead is a metal with no known benefit to animals or plants. It is toxic, especially with long term exposure
Babies and workers are most at risk. Low levels of lead can cause delayed development in foetuses and young children
In adults, high levels of lead can cause damage to the nervous system, reproductive system and kidneys. Lead collects in the bones and obstructs the use of calcium and vitamin D. Lead poisoning can lead to anaemia, kidney problems, high blood pressure and mental health problems – even convulsions and death at very high levels
Copper, on the other hand, is a metal that is required in very small amounts by humans and living organisms for life
High levels of copper can cause nausea, vomiting and stomach complaints
Children that are younger than one year old and people with Wilson’s Disease are very much more vulnerable to copper poisoning, as their bodies are not able to naturally regulate copper levels
Long term exposure can cause liver damage and kidney disease
Water containing high levels of copper is easy to pick up, as it is very unpleasant and bitter, thus copper poisoning is less likely than lead poisoning
Criteria in South Africa:
|0.1 mg / litre for discharge of effluent water to rivers 0.1 mg / litre for discharge of effluent water to other areas||0.02 mg / litre for discharge of effluent water to rivers 1.0 mg / litre – for discharge of effluent water to other areas|
|Drinking water:||Drinking water:|
|< 10 µg / litre||< 2000 µg / litre|