Avaliação ecotoxicológica do entecavir em Aliivibrio fischeri, Microcystis novacekii, Artemia salina, Biomphalaria glabrata e seu tratamento por processo oxidativo avançado e microbiológico.

Abstract

The presence of drugs routinely released into the environment, from production activities, services or even therapeutic use, is a potential pollutant of ecosystems, especially aquatic ones. The impact of drugs on the environment, in addition to the possibility of behavioral changes or death, can lead to gene or enzyme alterations, or both at the same time. Entecavir (ETV) is an antiviral used to treat hepatitis B virus (HBV) infection and is available from the Unified Health System (SUS). Around 68 to 73% of the drug is eliminated in unchanged form by the kidneys. The possible environmental impacts of ETV were assessed through ecotoxicological studies using Aliivibrio fischeri, Microcystis novacekii, Artemia salina and Biomphalaria glabrata as biological models. In addition, possible proposals for aqueous phase removal were proposed by means of the Fenton-like reaction and biodegradation using M. novacekii. A review of the literature regarding estimates of pharmaceuticals in the environment, with a focus on antiretrovirals and genotoxic alterations in A. salina in the presence of various pollutants, was also carried out in accordance with the PRISMA guidelines. It has been estimated that approximately 112 tons of antiretrovirals (ARVs) are released into the environment through human excretion, as well as inadequate disposal and failures in pharmaceutical effluent treatment. For the ecotoxicological studies with ETV, the biological models were exposed to a concentration gradient of the drug, for defined periods, and bioluminescence (A. fischeri), cell growth (M. novacekii), immobility (A. salina), behavior and death (B. glabrata) were evaluated as outcomes. The ecotoxicological results of ETV showed no acute toxicity at concentrations below 100 mg/L in the aquatic models studied. However, the failure to confirm acute toxicity in the biological models exposed to ETV cannot be seen as an absence of toxicity of this drug, and chronic toxicity studies should be carried out to complement the results. The application of the Fenton-like reaction to remove ETV proved to be effective and promising. After 90 seconds of reaction, the concentration of 300 mg/L reached an undetectable level. However, biodegradation by M. novacekii showed a low rate of ETV removal (maximum 28.9%) for direct use in the remediation of aquatic environments. The compilation of all these studies shows the pressures on the environment from antiviral drugs. Even though acute toxicity has not been verified for some biological models, as in the case of ETV, there is a potential for the development of resistance mechanisms in viruses, bacteria and even other higher organisms. In these cases, Artemia has proved to be a promising model for assessing the ecotoxicity of different types of chemical substances through genotoxicity tests. The possibility of monitoring organisms at lower trophic levels through metabolites and enzymatic activities can broaden the assessment of environmental impacts, especially in coastal ecosystems.