The research highlights high concentrations of polycyclic aromatic hydrocarbons (PAHs), which pose a significant threat to aquatic life, livestock, and human health.

Dr Mathapelo Seopela, a lecturer and researcher at the Department of Chemical Sciences at the University of Johannesburg, explained the severity of the findings. "The study reveals high concentrations of polycyclic aromatic hydrocarbons, which pose a significant threat to aquatic life, livestock, and human health. It is crucial for us to understand their distribution, the sources from which they originate, and the effects they have on the environment. This knowledge can guide measures to mitigate pollution and protect public health."

The research indicates that both high and low molecular weight PAHs were detected in the sediment, with the high molecular weight PAHs, which are more toxic, found in greater concentrations. These concentrations were notably higher during periods of low rainfall. "Our findings suggest that the Klip River is heavily contaminated with PAHs, particularly in areas near industrial activities, agricultural runoff, and human settlements. The levels we recorded exceeded the maximum permissible levels set by international guidelines, which underscores the serious risk posed to aquatic organisms and communities that depend on the river," Seopela said.

The study identified multiple sources of PAH contamination, including the combustion of materials, petroleum contamination, and petrogenic sources. These pollutants accumulate in sediments, impacting organisms differently based on where they live in the water. "If certain organisms spend more time in the surface water, they will be affected differently than those in the sediment. We have observed significant harm to fish embryos, such as the zebrafish test, which demonstrated serious developmental issues," she added.

The contamination of the Klip River raises urgent concerns about the potential health risks for local communities. "Yes, we should be worried," Seopela warned. "Previous studies already reported elevated levels of PAHs, and our research corroborates those findings, showing that the situation has worsened over time. Growing urbanisation, industrial activities, and domestic waste are exacerbating pollution levels, making this a critical environmental and public health issue. PAHs are known carcinogens, and prolonged exposure could have severe health consequences."

Addressing the pollution will require a multi-faceted approach, including stricter regulations, ongoing monitoring, and public education. "We need stringent regulations on industrial discharge into the river, as well as continuous monitoring of water quality. Policymakers and environmental agencies must use this research to develop targeted interventions. Additionally, educating communities about the health of their water sources and how they can contribute to clean-up efforts is essential," Seopela emphasised.

She also called for collaboration between government regulators, researchers, and industries to improve water management. "It is not just about policymakers; research institutions, environmental agencies, and industries need to come together to develop long-term solutions. We should also be expanding our monitoring efforts to include emerging pollutants, which are becoming an increasing concern globally."

Failure to take immediate action could have dire consequences. "If we do nothing, we are at risk of depleting our already scarce water resources, further lowering water quality, and exposing communities to long-term health issues," Seopela warned. She highlighted the need for innovative technologies such as wastewater treatment systems and biomonitoring tools to help mitigate the damage. "Long-term monitoring is necessary to track environmental trends and ensure that any mitigation measures implemented are effective. The data we gather will be crucial in informing evidence-based policy decisions to protect the Klip River and the communities that rely on it."

The study’s findings have intensified calls for urgent intervention to prevent further contamination and safeguard Gauteng’s water security. The future of the Klip River, and the people and wildlife that depend on it, hinges on decisive action from policymakers, industries, and local communities alike.

--ChannelAfrica--