ARVs in rivers: People, nature at risk

A study has found that lopinavir and efavirenz are the top pollutants in water bodies, many associated with wastewater treatment plants

- Sheree Bega

Significant concentrations of antiretroviral drugs (ARVs) have been detected in South Africa's water sources, particularly downstream of wastewater treatment plants, new research has found.

The drugs most frequently detected were lopinavir and efavirenz, with concentrations at some sites far exceeding global norms. This is attributed to South Africa's HIV treatment programme, the most extensive of its kind in the world.

The research, by North-West University's unit for environmental sciences and management and its Africa unit for transdisciplinary health research, included professors Suranie Horn, Rialet Pieters, Henk Bouwman and Petra Bester.

The study found that aquatic ecosystems and wastewater management systems were affected. Freshwater snails exposed to ARVs exhibited altered embryonic development, while bacteriophages — viruses critical to controlling bacteria in wastewater treatment — were significantly affected. Such disruptions could lead to bacterial blooms and reduced water quality, the authors said.

"The consumption of any type of exogenous drug by any organism in sufficient quantities may intervene with the regulation of metabolic systems and bring about adverse effects," said the study, warning that the presence of antiretrovirals in water "can be considered a hidden or latent risk".

The potential risks for human health were also red-flagged.

"Humans are also exposed to these compounds via drinking water, and at concentrations exceeding calculated hazard quotients," the authors said. "Although not found in this study, humans and other organisms may potentially ingest antiretrovirals and their breakdown products via aquatic organisms such as fish."

Concentrations of ARVs in some water sources exceeded acceptable thresholds. Current wastewater treatment processes are inadequate for removing these bioactive compounds, underlining the need for technological advancements.