Effects of Advanced Treatments of Wastewater Effluents on Estrogenic and Reproductive Health Impacts in Fish

Abstract

Whether the implementation of additional treatments for the removal of estrogens from wastewater treatment works (WwTWs) effluents will eliminate their feminizing effects in exposed wildlife has yet to be established, and this information is crucial for future decisions on investment into WwTWs. Here, granular activated carbon (GAC), ozone (O(3)), and chlorine dioxide (ClO(2)) were investigated for their effectiveness in reducing steroidal estrogen levels in a WwTW effluent and assessments made on the associated estrogenic and reproductive responses in fathead minnows (Pimephales promelas) exposed for 21 days. All treatments reduced the estrogenicity of the standard-treated (STD) effluent, but with different efficacies; ranging between 70-100% for total estrogenicity and 53-100% for individual steroid estrogens. In fish exposed to the GAC- and ClO(2)- (but not O(3)-) treated effluents, there was no induction of plasma vitellogenin (VTG) or reduction in the weight of the fatpad, a secondary sex character in males, as occurred for fish exposed to STD effluent. This finding suggests likely benefits of employing these treatment processes for the reproductive health in wild fish populations living in rivers receiving WwTW discharges. Exposure of pair-breeding minnows to the GAC-treated effluent, however, resulted in a similar inhibition of egg production to that occurring for exposure to the STD effluent (34-40%). These data, together with a lack of effect on egg production of the estrogen, ethinylestradiol (10 ng/L), alone, suggest that chemical/physical properties of the effluents rather than their estrogenicity were responsible for the reproductive effect and that these factor(s) were not remediated for through GAC treatment. Collectively, our findings illustrate the importance of assessing integrative biological responses, rather than biomarkers alone, in the assessment and improvement of WwTW technologies for the protection of wild fish populations.

Contaminantes emergentes em matrizes aquáticas do Brasil: cenário atual e aspectos analíticos, ecotoxicológicos e regulatórios

“…108 Com relação aos ftalatos, Singh e Li reportaram vinte doenças associadas à exposição a três principais compostos (DnOP, BBP e DEHP), incluindo disfunções no sistema endócrino, genital e uroló-gico, complicações no fígado e doenças cardiovasculares. 139 Outros estudos mostraram que a exposição de diferentes organismos frente aos interferentes endócrinos levaram à ocorrência de efeitos como a feminização de peixes, [140][141][142][143][144][145][146][147][148][149] alterações no desenvolvimento de moluscos e anfíbios, [150][151][152][153][154] disfunções no metabolismo da testosterona em Daphnias 155,156 e o desenvolvimento anormal de órgãos em diferentes organismos aquáticos. 19,146,149,150,157,158 Na Índia, após observarem o declínio de cerca de 95% da quantidade de uma espécie de urubus (Oriental white-backed vulture) na década de 90, Oaks e colaboradores apresentaram fortes evidencias de que as doenças renais que afetaram os animais foram decorrentes da ingestão de resíduos de diclofenaco presentes nas carcaças de búfalos e cabras tratados com o fármaco.…”

“…Esses bioensaios podem empregar diferentes mecanismos de detecção incluindo: proliferação de células; LBA (do inglês, Ligand Binding Assay); indução de vitelogenina, proteína produzida no fígado de peixe fêmea em resposta aos estrógenos, que pode ser extraída do plasma e quantificada (a produção de vitelogenina em organismos machos é um indicativo de interferência endócrina que tem sido explorado em diversos estudos); 70,123,141,148 indução de luciferase (termo genérico empregado para diferentes enzimas oxidativas que produzem bioluminescência durante a reação enzimática) e interações antígeno-anticorpo como os bioensaios YES (do inglês, Yeast Estrogen Screen), 194 BLYES (do inglês, BioLuminesce Yeast Estrogen Screening), CALUX (do inglês, Chemical Activated LUciferase gene eXpression). 123 O bioensaio denominado YES, desenvolvido por Routledge e Sumpter em 1996, 194 vem sendo largamente utilizado para a avaliação da atividade estrogênica 195 de amostras ambientais tais como efluentes de ETE, [196][197][198][199] águas superficiais 9,51,93,200 e água tratada, 19,20 bem como para avaliar a eficiência de diferentes tipos de tratamento de efluentes.…”

Use of a Battery of Chemical and Ecotoxicological Methods for the Assessment of the Efficacy of Wastewater Treatment Processes to Remove Estrogenic Potency

“…In vivo studies using fish (e.g., roach or fathead minnow) exposed to wastewater show female germ cells or oocytes in the testis of male fish (e.g., as seen in Figure 5). Intersex or male VTG is absent or significantly reduced in fish following advanced treatment such as GAC 7 or ozone 22 . These studies show that transformation products produced during ozonation are not estrogenic, however this does not address the toxicity of the effluent produced.…”

“…However, there has been some success with producing estrogen responsive transgenic glowing fish embryos 30 , which could have future applications. Fathead minnows (used in this protocol) are a common laboratory species and VTG induction in male fish is a well-documented bio-marker of estrogenic exposure and a quantifiable measure of wastewater effluent estrogenicity 22 or other estrogenic compounds or mixtures 31 . OECD test guidelines for endocrine disrupting chemicals have been validated using adult fathead minnow, Japanese medaka and zebrafish 32,33 , with VTG being a sensitive biomarker of estrogen exposure in all three species.…”

Ecotoxicological evaluation of three tertiary wastewater treatment techniques via meta-analysis and feeding bioassays using Gammarus fossarum

“…Afterwards, wastewaters were aerated for another 12 h. Gammarids were exposed to river water from the Hainbach (=control), ozone treated, PAC treated, TiO 2 and UV treated and secondary treated (=biology) wastewater. For the experiment conducted with wastewater from WWTP Vidy respective treatments were supplemented by PAC treated wastewater amended with nutrients according to the concentrations described by Borgmann [23] for the SAM-S5 medium, as literature suggests that essential trace-elements may be removed by PAC [24,25].…”