The increased global use of antiviral and antiretroviral medication could have a detrimental impact on crops and potentially heighten resistance to their effects, new research has suggested.
Scientists from the UK and Kenya found that lettuce plants exposed to a higher concentration of four commonly-used drugs could be more than a third smaller in biomass than those grown in a drug-free environment.
They also examined how the chemicals transferred throughout the crop and found that, in some cases, concentrations were as strong in the leaves as they were in the roots.
The study – published in Science of the Total Environment – was conducted by environmental chemists from the University of Plymouth (UK), Kisii University (Kenya) and Jomo Kenyatta University of Agriculture and Technology (Kenya).
It is one of the first worldwide to examine the impact of pharmaceutical compounds on agriculture, and to consider the subsequent risks for consumers.
For it, scientists focused on the drugs nevirapine, lamivudine and efavirenz – which are used to treat and prevent HIV/AIDS – and oseltamivir, which stops the spread of the flu virus in the body.
However, they say it is also relevant in light of the current COVID-19 pandemic, with antiviral medications having been approved for use to treat those affected by the virus.
Such compounds get into soils when they are irrigated with contaminated surface water, treated or untreated waste water, sewage sludge and biosolids.
Through a series of analyses, they showed there were differing levels of uptake across the four drugs with lamivudine exhibiting the lowest bioaccumulation – a level similar to that shown previously with caffeine.
However, when exposed to a combination of the four drugs (as would be found in the wider environment) mean leaf and root mass was reduced by 34%.