Investigating the effects of the ARV drug efavirenz in South African surface waters on fish health

This is a laboratory exposure study that aimed to investigated the effects of chronic (28-days) efavirenz exposure on the liver and kidney tissues of O. mossambicus (red strain variety). Two exposure concentrations were used, 10.3 ng/L and 20.6 ng/L, as per Robson et al. (2017). In total, 72 fish were exposed in a controlled environment using a static-renewal system, and standard histological techniques were used to assess the liver and kidney tissues. Steatosis and fibrosis in liver tissues were prevalent, confirming the hepatotoxicity of efavirenz. Additionally, high levels of efavirenz bioaccumulated in the liver (84 mg/kg). The kidney presented renal cysts, fibrosis, and tubular vacuolation showing potential renal toxicity of efavirenz.