Cyanide traced in Enkomeni streams
BARBERTON - A year ago, Lowvelder came into possession of a leaked water test report by ARC Onderstepoort Veterinary Institute, proving that drinking water from wells along an unnamed tributary of the Queens River near Enkomeni had tested positive for cyanide.
Onderstepoort’s toxicology tests on livestock that died near the wells warned of potential dangers to human health.
The report stated: “Both of the water samples tested negative for nitrates and positive for cyanide. If the rivers are also contaminated, we suggest that the matter be handed over to environmental affairs and that a comprehensive water quality analysis be done.”
The tests were conducted after the death of more than 20 livestock from suspected poisoning a year ago. The dead cattle and goats were found near wells that illegal miners use to process gold.
Lowvelder forwarded the toxicology results to the Inkomati-Usuthu Catchment Management Agency (IUCMA) a year ago and continued to put pressure on it to investigate the potential poisoning of Enkomeni’s water sources.
On November 21, the IUCMA’s spokesperson, Sylvia Mahimana, gave reassuring feedback.
“IUCMA monitors the levels of cyanide in the Queens River at a point downstream of the incident and the levels of cyanide in the river are lower than the detection limit of 0.07mg/L.”
According to the World Health Organisation, people should not drink or use water with a cyanide concentration above 0.5mg/L for more than five days.
The water samples taken in the tributary also showed elevated levels of sulphate, arsenic and electrical conductivity, compared to a point upstream of the cattle incident where illegal beneficiation of minerals was taking place.
“It is near impossible to determine if there is a causal link between cattle deaths and cyanide. While it is known that cyanide is toxic, there should also be proof beyond reasonable doubt that lethal levels have been exceeded, which at this stage is not possible due to detection limitations.”
Dr Tatenda Dalu, a University of Mpumalanga water management lecturer, said, “I believe further observations or checks need to be conducted on the local [human] population to see whether they are affected, checking for any potential symptoms.”
Mahimana said, “The municipality has a responsibility to provide clean [treated] potable water to its residents and to put in place a water safety plan and mitigation measures to address any identified risks that could compromise the quality of their potable water.
“It is our responsibility to investigate the source of pollution, especially if the activity has a potential to compromise fitness for water users’ consumption. Hence, the samples were taken and analysed accordingly, and the source of pollution identified as illegal beneficiation of minerals in proximity of water resources.”
The lethal dose of cyanide (CN) for an adult human is 1.5mg CN/kg of bodyweight. Prolonged exposure to cyanide by drinking or ingesting contaminated water can lead to hypothyroidism, kidney damage and miscarriages.
Dalu said cyanide ingestion could cause tremors, rapid breathing and other neurological effects if consumed above the recommended levels in drinking water.
Mahimana stressed, “It is necessary to clarify the fact that communities are not expected to drink raw untreated water coming out of streams, as this is indeed a high risk for contracting waterborne diseases.”