Environmental contamination by fluoroquinolones

Abstract

Over the past few decades, a high number of pharmaceuticals have been detected in surface, ground and drinking waters. This contamination comes from domestic sewage, livestock, hospitals and chemicalpharmaceutical industries. Typical examples of these pollutants are the fluoroquinolones -powerful antibiotics used in human and veterinary medicine. The presence of fluoroquinolones in the environment can pose a serious threat to the ecosystem and to human health due to their high consumption globally: in 1998, around 120 tons were produced. Even at low environmental concentrations, antibiotics stimulate bacterial resistance. The consequences of the presence of fluoroquinolones in the environment are not fully understood, but are known to be toxic to plants and aquatic organisms. Approximately 85% of the fluoroquinolones present in influents can be removed by conventional wastewater treatment plants, but the removed fraction is frequently accumulated in the sludge, which is sometimes used as fertilizer, representing an additional input route into the environment. The removal of fluoroquinolones by biological treatment is ineffective, and it is believed that only advanced oxidation technologies are able to destroy these emerging pollutants.Uniterms: Fluoroquinolones/waste/environmental impact. Fluoroquinolones/waste/environmental contamination. Environmental contamination. Advanced oxidation processes/wastewater treatment.Nas últimas décadas, um grande número de fármacos tem sido identificado em águas superficiais, subterrâneas e potáveis. Tal contaminação advém do esgoto doméstico, hospitais, criação de animais e das indústrias químico-farmacêuticas. Exemplos típicos desses poluentes são as fluoroquinolonaspotentes antibióticos empregados na medicina humana e veterinária. A presença de fluoroquinolonas no meio ambiente pode representar uma séria ameaça para o ecossistema e para a saúde humana devido ao alto consumo mundial: em 1998 foram produzidas, aproximadamente, 120 toneladas. Mesmo em baixas concentrações, antibióticos podem estimular a resistência bacteriana. As consequências da presença de fluoroquinolonas no ambiente não são completamente compreendidas, mas sabe-se que são tóxicas para plantas e organismos aquáticos. Aproximadamente 85% das fluoroquinolonas presentes em efluentes podem ser removidos em estações de tratamento de efluentes convencionais, porém a fração removida é frequentemente acumulada no lodo, muitas vezes usado como fertilizante, o que representa uma rota adicional de entrada desses compostos no ambiente. A remoção de fluoroquinolonas por meio de tratamento biológico não é eficiente, e acredita-se que somente as tecnologias de oxidação avançada sejam capazes de degradar esses poluentes emergentes.Uniterms: Fluorquinolonas/resíduos/impacto ambiental. Fluorquinolonas/resíduos/contaminação ambiental. Contaminação ambiental. Processos oxidativos avançados/tratamento de águas residuais.

Implications of fluoroquinolone contamination for the aquatic environment—A review

“…The removal fraction accumulated higher concentrations of fluoroquinolones in the treated byproduct sludge (biosolids portion). The biological treatment used in some WWTPs was ineffective in fully degrading and deactivating fluoroquinolones because only advanced oxidation technologies are able to remove such compounds . This is cost prohibitive in most municipalities.…”

“…A wide range of concentrations is considered toxic to cyanobacteria, algae, and some invertebrate and vertebrate species (e.g., crustaceans, frogs, fish) . Rico et al evaluated the acute toxicity (48 h) of enrofloxacin to 5 invertebrate species within and around tilapia farms in Thailand—an aquatic oligochaete ( Limnodrilus hoffmeisteri ), 2 molluscs ( Physella acuta and Melanoides tuberculata ), an insect ( Micronecta sp.…”

Batch and Fed‐Batch Degradation of Enrofloxacin by the Fenton Process

“…Taking into account that the molecules of fluoroquinolones [13] and tetracyclines [19] basically have four rings in their structures and that the compounds belonging to both classes differ from one another in the peripheral functional groups, it can be inferred that tetracyclines are more easily attacked by hydroxyl radicals than fluoroquinolones.…”

“…Enrofloxacin [1-cyclopropyl-7-(4-ethylpiperazin-1-yl)-6fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid] is a synthetic second-generation fluoroquinolone used as an antimicrobial agent exclusively in veterinary medicine. It acts by inhibiting bacterial DNA gyrase, thereby preventing DNA supercoiling and synthesis, has a broad spectrum of action, and is recommended for the treatment of a large number of infectious diseases caused either by Gram-positive or Gram-negative bacteria, mycoplasmas, and spirochetes [10][11][12][13].…”

Degradation of Vancomycin Hydrochloride by Electrooxidation

“…However, soil fertilization with manure and effluents from the pharmaceutical industry cannot and should not be disregarded. Antidepressants [3], anti-inflammatories [4], contraceptives [5] and antibiotics [6] are found in wastewater treatment plants (WWTPs), surface waters and groundwater with concentrations in the ng and μg L -1 bands. Antibiotics occupy a prominent place among the classes of drugs spread in human and animal medicine.…”