The ManicaPost
Cletus Mushanawani
News Editor
ILLEGAL panning activities around Mutare’s water sources are threatening thousands of lives in the city as high levels of mercury have been detected in Lake Alexander Dam which supplies 25 percent of the city’s potable water, The Manica Post can reveal.
After Mutasa Rural District Council collected water samples from Lake Alexander and Small Bridge Dam on February 16, the Standards Association of Zimbabwe (SAZ) ran laboratory tests and picked high levels of mercury in the water.
According to a SAZ report dated March 9, 2022, referenced CFT-220218-00058 which this paper has in its possession, mercury levels stood at 0, 898 milligrammes per litre in the Lake Alexander water samples, while the chemical was not detected in Small Bridge Dam.
The results show that 0, 018 milligrammes of cyanide per litre were detected from the Lake Alexander samples, and 0, 016 milligrammes per litre in samples collected from Small Bridge Dam.
Samples picked by The Manica Post also showed high levels of sediments.
According to SAZ, the maximum limit of mercury allowed in water is 0, 02mg/l as the chemical is regulated as a primary drinking water standard, hence the presence of 0, 898mg/l of mercury in Lake Alexander is far above the standards and poses danger to humans and aquatic life.
Cyanide tanks have been constructed on several sites in Penhalonga. Cyanide is used to dissolve gold from the ore. Due to its harsh properties, cyanide is not supposed to interact with the environment. Recent tests of water samples collected from nearby water sources suggest that the cyanide solution is leaking into the environment
Both the Environmental Management Agency and SAZ confirmed the tests.
In industries where mercury and cyanide are used, there is a need for better and more expensive methods of recycling, cleaning and decontamination of the affected water.
In a telephone interview from Harare, SAZ acting manager (Chemical and Food Technology), Ms Joyce Mufara confirmed that they carried out tests on samples that were brought in by Mutasa Rural District Council.
“While we can only give further details with the consent of that local authority, if the report you have in your possession has our letterhead and date stamp, those results are genuine,” said Ms Mufara.
EMA’s Manicaland provincial manager, Mr Kingstone Chitotombe, said they were carrying out monthly tests up to December to determine the mercury and cyanide levels.
“We are carrying out monthly tests of water from tributaries that feed into Lake Alexander and Small Bridge Dam as well as in Mutare River to determine the cyanide and mercury levels. From the test results which we got from SAZ, they showed high levels of mercury in Lake Alexander. Lake Alexander supplies 25 percent of Mutare’s potable water, hence this poses a serious threat to the community.
“We have notified all the relevant stakeholders on the development, but there is no need to press the panic button as regular tests will be done. We have also contacted the police to intensify their raids and bring sanity in the gold mining areas. As the Government advisory agency, we will continue advising the public accordingly,” he said.
Mr Chitotombe, in his letter to the Officer Commanding Police in Manicaland which is dated April 7, 2022, called for the effective management of illegal mining activities.
“The panners use mercury to trap gold. Mercury is a heavy metal that will eventually find its way into the food web and may result in serious health related problems as in the case with the Minamata disease in Japan. So in order to manage mercury levels, there is need to effectively manage illegal mining activities,” he wrote.
The Minamata disease is a poisoning disease that affects mainly the central nervous system and is caused by the consumption of large quantities of fish and shellfish living in Japan’s Minamata Bay and its surroundings, the major causative agent being some sort of organic mercury compound in the water bodies.
In a report compiled by EMA’s Manicaland provincial environmental quality officer, Mr Victor Mudyiwa dated April 8, 2022, it is stated that mercury is a potent neurological poison that is easily absorbed easily into the food chain.
Part of the report reads: “Mercury is one of the most serious contaminants threatening our nation’s water bodies because it is a potent neurological poison in fish, wildlife and humans. It is a pollutant that makes its way into every aquatic ecosystem through point-source discharges and atmospheric deposition.
“Mercury is a major concern because it is absorbed easily into the food chain. The harmful methyl-mercury form of mercury readily crosses biological membranes and can accumulate to harmful concentrations in the exposed organism and become increasingly concentrated up the food chain.
“This bio-accumulation can cause high levels of mercury in top predator fishes (which people eat) and have a detrimental effect on humans and fish-eating wildlife.”
The report goes further to note: “Mercury’s health effects include impairment of hearing, speech, vision and gait. It also causes involuntary muscle movements, corrosion of skin and mucous membranes, as well as making chewing and swallowing difficult.
Illegal mining shafts are dotted across the Redwing Mine concession in Penhalonga, with plastic shacks erected to cover entrances in an effort to avoid flooding and mine collapses. − Pictures: Tinai Nyadzayo
“Like many contaminants in drinking water, this element is potentially hazardous at levels or concentrations that do not impart a noticeable taste, odour or appearance to the water,” reads Mr Mudyiwa’s report.
He attributed the main source of mercury in Lake Alexander to mining and the processing of gold using the chemical within the stream’s watershed.
According to the World Health Organisation (WHO), mercury is one the most harmful substances for human health. It can influence the nervous system, the development of the brain, and more. It is particularly harmful for children and can also be transmitted from a mother to a child during pregnancy.
Mutare medical practitioner, Dr Prudence Mhlanga, reiterated this.
“Mercury and cyanide are poisonous to people. High levels of cyanide affects metabolism and can lead to death. It can affect the heart and liver. Mercury can cause central nervous systems problems. People may suffer from sleeping disorders and bodily imbalances. Stakeholders should continuously test the water and advise residents accordingly,” he said.
Officials from Mutare City Council remained tight-lipped on the issue and had not responded to questions sent to them last week despite making endless promises to do so.
Manicaland provincial police spokesperson, Inspector Nobert Muzondo said they carry out frequent raids to flush out the illegal gold panners in Penhalonga.
Besides the contamination of water bodies, EMA also reported that the panning activities are causing severe land degradation along Nyakaunga Stream.
A recent field tour to the Sheba area revealed that about 15ha of land has been degraded along Nyakaunga Stream, all the way up to the panning area.
It was also noted that there is severe siltation along the river and in the dam.
