Evaluation of the use of Leptodactylus ocellatus (Anura: Leptodactylidae) frog tissues as bioindicator of metal contamination in Contas River, Northeastern Brazil

Abstract

This paper presents a study on the viability of the use of tissues of the Leptodactylus ocellatus species (Anura Leptodactylidae) as a bioindicator of metal pollution. The study is based on the determination and correlation of the concentrations of manganese, chromium, zinc, nickel, copper and iron in sediments and tissues (skin, muscles and viscera) of the frog Leptodactylus ocellatus collected in the middle region of the Contas River in Bahia, Brazil. The highest levels of the metals studied were found in the viscera of this animal. In this tissue, a higher correlation of the concentration of these metals with those found in sediments was also observed. The concentrations of elements found in the skin and muscles of these amphibians have revealed no correlation with the sediment where they were collected. According to the results obtained, the viscera of the L. ocellatus species presents itself as a good bioindicator of contamination by the metals studied.

Neuroendocrine disruption of organizational and activational hormone programming in poikilothermic vertebrates

“…In amphibians embryogenesis is ex vivo, their skin is permeable and they go through metamorphosis. For these reasons, amphibians are considered highly sensitive test organisms for hormone-dependent development (Tata 2006) and employed in ecotoxicological assessments (Santos et al 2015; Correia et al 2014; Maselli et al 2010; da Rosa, 2016; Gardner et al, 2017), including standard methods such as the Amphibian Metamorphosis Assay (OECD), and the Frog Embryo Teratogenesis Assay-Xenopus (FETAX) (ASTM). Anuran metamorphosis, and in particular the neuroendocrine control of the process, may represent a reliable model system to examine NED; since it is a process dependent upon TH consisting of thyroxine (T4) and triiodothyronine (T3) (Ishizuya-Oka 2011; Sachs et al 2000), and considered equivalent to postembryonic organogenesis in mammals (Tata 2006).…”

>b<Alterações morfológicas em tecidos linfoide e endócrino de anuros sujeitos à contaminação ambiental em áreas cultivadas no estado do Ceará>/b<

“…Segundo D'Ávila et al(2020), em ampla revisão de estudos de associação de contaminantes químicos com o declínio global de anfíbios, as famílias Hylidae, Ranidae e Bufonidae têm sido as mais estudadas ao longo das últimas quatro décadas, principalmente na América do Norte. Somente nos últimos anos, os membros da família Leptodactylidae vem sendo utilizados como modelos e bioindicadores ambientais na América do Sul(VIANA, 2010;CORREIA et al, 2014).Revisando a literatura publicada sobre o tema na América do Sul, foram levantadas 85 publicações, através dos descritores "Leptodactylidae", "environment", "toxicity", "biomarker", "Brazil" no Google Scholar. A revisão compreendeu 63 artigos de periódicos científicos revisados por pares, 20 itens de literatura não revisada por pares (14 dissertações, 2 teses, 3 monografias e 1 resumo de evento), e dois capítulos de livro, realizados na Argentina, no Uruguai e no Brasil, publicados entre 2004 e 2020.No Brasil, dentre os trabalhos realizados com Leptodactilídeos como bioindicadores de contaminação química orgânica e inorgânica ambiental espontânea, publicados em periódicos revisados por pares, destacaram-seCorreia et al (2014),Moresco et al.…”