As Day Zero moves out and with dam levels still critically low, Capetonians now wonder about the quality of the drinking water that comes from their municipal taps. Scientists are also warning of the possibility of geosmins being present, which effects the taste of water. These geosmins, together with unwanted disinfectant by-products come from algae blooming in our dams and the chlorination process needed to remove such bacteria. As a result, more and more South Africans are purchasing water purifiers to personally ensure the quality of their drinking water.
In October last year Bill Harding, an internationally recognised algologist, warned that “the drought, seen in the main as a shortage of water – a quantity issue – also embodies a very real quality threat.”
He went on to say that “Theewaterskloof (the largest bulk supply for Cape Town) and Voelvlei (second largest) have long suffered from cyanobacterial (blue-green algal) blooms, and both feature increasingly in the ‘high risk’ end of the Water Research Commission developing project on satellite-monitored algal blooms.”
By early March 2018, both dams were designated “very high risk” on the Earth Observation National Eutrophication Monitoring Programme (EONEMP).
According to the World Health Organisation, “Disease due to cyanobacterial toxins varies according to the type of toxin and the type of water or water-related exposure (drinking, skin contact, etc.). Humans are affected with a range of symptoms including skin irritation, stomach cramps, vomiting, nausea, diarrhoea, fever, sore throat, headache, muscle and joint pain, blisters of the mouth and liver damage.” These symptoms can require “intensive hospital care”.
The dominant algae in the Western Cape dams is now thought to be Anabaena, the genus known to produce cyanotoxins such as anatoxin-a (known as Very Fast Death Factor). In 2015 researchers found an Anabaena strain containing microcystin-LR in Theewaterskloof Dam. Microcystin-LR is the most toxic of the microcystins produced by cyanobacteria.
So, while we are assured that our water is currently safe, there is certainly cause for concern about whether it will remain so, especially as the WHO warns that chlorine used inappropriately can rupture cell walls of cyanobacteria and release toxins into supposedly treated water. In 1995, this led to acute neurotoxicity in 120 patients on dialysis in Brazil, which proved fatal in 60 cases.
Capetonians and South Africans in other drought-stricken regions have been focusing on acquiring rain-water tanks and grey-water tanks, boreholes and well points. Now, even though we are told our taps will not run dry in April, many South Africans are looking to install water purifiers.
The correct water purifier can remove carcinogens, neurotoxins, hepatotoxins and chemicals from municipal tap water, confirms Tony Marchesini, managing director of H2O International SA. “The only way to be completely sure your tap water is safe is to purify it through a filter that removes all contaminants, including toxic bacteria, heavy metals, pharmaceuticals and chemicals,” says Marchesini. “The better the technology used to produce the purifier, and the larger the media bed, the more certain you can be that you are not subjecting yourself or your loved ones to the toxins that could be present.”
H2O was founded in South Africa in the early 1990s with a focus on providing the local market with water purifiers and coolers that utilise the advanced technology and materials to produce healthy drinking water.
“Try to avoid reverse osmosis if you’re looking to purify your tap water. This process is known to waste up to 3 litres for every 1 litre of purified water. Rather look for a filter like the H2O International water purifiers that use the world’s leading and unique GAC/ KDF®/Riolyte® technology and don’t waste any water. These days we can’t afford to waste a single drop!”
Marchesini offers one further warning: “Remember some of these blue-green algae will eventually clog water filters, so always follow the manufacturer’s instructions and replace filters as required.”
For more information on H2O International please visit www.h2o.co.za or call (021) 702-3262.