The Sunday Mail
Senior health officials have warned that the continued discharge of chemicals and unknown substances into drinking water systems could in the long run lead to chronic ailments such as cancer and blood poisoning.
Concerns abound that some metal elements underground are also finding their way to the consumer as the available treatment methods do not screen such contaminants.
Reacting to the unfolding revelations of water pollution across the country, Harare City Health Services director Dr Prosper Chonzi challenged polluters, especially industries, to disclose all the chemicals they have been dumping into water sources.
Dr Chonzi said it would remain difficult to rid water of all contaminants if the full list of pollutants were unknown.
Chief among the known elements that can cause major health complications are zinc, magnesium, chromium, lead and iron.
Harare and Bulawayo top the list of urban centres whose water systems are being contaminated by raw sewage and industrial waste. It is estimated that 3 885 mega-litres of waste are being dumped into the capital’s water sources daily.
In Bulawayo, 13 mega-litres of effluent are being discharged into Mazai River, which feeds into Umguza River everyday.
Dr Chonzi said metals act on the human body system differently, depending on their composition.
“Our water treatment process can only purify water from infectious elements, leaving the water with other non-organic pollutants such as zinc, magnesium and industrial excrements that have not yet been established.
“Such elements may result in the water consumer developing cancerous cells and blood poisoning, among other chronic diseases.
“Our main worry is that we do not know what we are going to fight in the next 10 years as repercussions of consuming such water.”
Commenting broadly on the impact of chemical and metal contaminants, Government Analyst Laboratory director Mr Livingstone Musiyambiri said most effects are long-term.
Mr Musiyambiri said other non-organic matter such as lead and chromium could lead to metabolic poison, anaemia, slight abdominal discomfort and behavioural change in children.
“Human bodies require iron, which is part of haemoglobin. However, the continuous consumption of water characterised by too much iron (hard water) can cause common diarrhoea.
“Hard water can also cause rusty deposits on teeth, which lead to bleeding gums.
“These pollutants may not be directly consumed, but someone may eat food that contains the element, for instance, fish that survive in polluted water.
“In the long run, the elements will accumulate, eventually causing metabolic poisoning.”