Estrogenic activity and reproductive effects of the UV-filter oxybenzone (2-hydroxy-4-methoxyphenyl-methanone) in fish (original) (raw)

UV Filters in the Aquatic Environment Induce Hormonal Effects and Affect Fertility and Reproduction in Fish

CHIMIA, 2008

UV-absorbing organic chemicals (UV filters) are being increasingly used in sunscreens, personal care products and in the protection of materials against UV irradiation. Environmental contamination originates from direct input from recreational activities and wastewaters. Concentrations in treated wastewaters are in the lower ?g/l range, whereas in rivers and lakes they are in the range of a few up to hundreds of ng/l. It is known that lipophilic UV filters accumulate in aquatic biota, but only little is known about their environmental fate. A large number of UV filters elicit hormonal effects in vitro. Estrogenic activity has also been demonstrated for some UV filters in fish in vivo. Benzophenone-1 (BP1), benzophenone-2 (BP2), 3-benzylidene camphor (3BC) and ethyl-4-aminobenzoate (Et-PABA) lead to induction of vitellogenin. 3BC and BP2 cause feminization in secondary sex characteristics of male fish, alteration of gonads in male and female fish and decrease in fertility and reprodu...

Contaminant effects on reproductive success in selected benthic fish

Marine Environmental Research, 1993

Field studies on ovarian development in English sole from urban and nonurban sites in Puget Sound, Washington, USA, demonstrated that animals with elevated levels of fluorescent aromatic compounds (FACs) in bile were less likely to enter vitellogenesis and had lower plasma ...

Non lethal concentrations of pesticide impair ovarian function in the freshwater perch,Anabas testudineus

Environmental Biology of Fishes, 1993

Anabas testudineus were treated with non lethal levels of metacid-50 (0.106 ppb) and carbaryl(1.66 ppm) for 90 days covering the pre-spawning and spawning phases of the annual reproductive cycle. The main purpose of the present work was to identify the effects of metacid-50 and carbaryl on the gonado somatic index (GSI) and ovarian and plasma estrogen level. There was no alteration in GSI until 15 days, initiating the inhibition on day 20 which further intensified from 20 to 90 days of exposure. Plasma and ovarian estrogen level significantly increased up to 15 days of exposure followed by a decline till the end of the experiment. It is noteworthy that the effect of pesticides on GSI is reflected in the ovarian estrogen level. This highlights the fact that at short-term exposures the nonlethal levels of pesticides have no inhibitory effect while at long-term exposure, the pesticides have potent inhibitory effect on the reproduction of fish.

Effects of the UV filter benzophenone-3 (oxybenzone) at low concentrations in zebrafish (Danio rerio)

2012

Organic UV filters including benzophenone-3 (BP-3) are widely used to protect humans and materials from damage by UV irradiation. Despite the environmental occurrence of BP-3 in the aquatic environment, little is known about its effects and modes of action. In the present study we assess molecular and physiological effects of BP-3 in adult male zebrafish (Danio rerio) and in eleuthero-embryos by a targeted gene expression approach focusing on the sex hormone system. Fish and embryos are exposed for 14 days and 120 hours post fertilization, respectively, to 2.4-312 μg/L and 8.2-438 μg/L BP-3. Chemical analysis of water and fish demonstrates that BP-3 is partly transformed to benzophenone-1 (BP-1) and both compounds are accumulated in adult fish. Biotransformation to BP-1 is absent in eleuthero-embryos. BP-3 exposure leads to similar alterations of gene expression in both adult fish and eleuthero-embryos. In the brain of adult males esr1, ar and cyp19b are down-regulated at 84 μg/L BP-3. There is no induction of vitellogenin expression by BP-3, both at the transcriptional and protein level. An overall down-regulation of the hsd3b, hsd17b3, hsd11b2 and cyp11b2 transcripts is observed in the testes, suggesting an antiandrogenic activity. No histological changes were observed in the testes after BP-3 treatment. The study leads to the conclusion that low concentrations of BP-3 exhibit similar multiple hormonal activities at the transcription level in two different life stages of zebrafish. Forthcoming studies should show whether this translates to additional physiological effects.

Endocrine disrupting chemicals and sexual behaviors in fish – a critical review on effects and possible consequences

Critical Reviews in Toxicology, 2012

Endocrine disrupting chemicals (EDCs) enter aquatic ecosystems through discharged effluents, mainly from wastewater treatment works and diffuse run off from land, and affect a wide range of aquatic biota, including fish. Evidence for altered physiology in fish as a consequence of endocrine disruption is global, with some of the most widely reported effects on sexual development and function. In recent years research has shown that fish behaviors can also be affected by EDCs which potentially has wide implications for individual fitness and population level outcomes. This review presents a critical assessment on reported effects of EDCs on behavior in fish, focusing on behaviors associated with reproduction. We investigate commonalities and differences in sexual behaviors between fish species most commonly applied in ecotoxicology, drawing out common principles for impacts of EDCs and then reviewing the evidence for, and implications of, disruptions of these behaviors after exposures to EDCs. In an analysis of the reported effects of exposure to the estrogen, ethinylestradiol, we show that life-stage at exposure is a key factor determining behavioral responses of affected populations. EDC-induced changes in behavior occur at similar concentrations as for established biomarker responses (e.g. vitellogenin induction for estrogens), indicating behavior is equally sensitive (and non-invasive) as an indicator of EDC exposure. Adopting behaviors in fish as indicators of chemical exposure and effects, however, still has many technical and interpretation challenges and there is very little information available on how behaviors under laboratory conditions equate with those occurring in wild populations.

Endocrine Toxicants and Reproductive Success in Fish

Human and Ecological Risk Assessment: An International Journal, 2001

There is compelling evidence on a global scale for compromised growth and reproduction, altered development, and abnormal behaviour in feral fish that can be correlated or in some cases causally linked with exposure to endocrine disrupting chemicals (EDCs). Attributing cause and effect relationships for EDCs is a specific challenge for studies with feral fish as many factors including food availability, disease, competition and loss of habitat also affect reproduction and development. Even in cases where there are physiological responses of fish exposed to EDCs (e.g., changes in reproductive hormone titres, vitellogenin levels), the utility of these measures in extrapolating to whole animal reproductive or developmental outcomes is often limited. Although fish differ from other vertebrates in certain aspects of their endocrinology, there is little evidence that fish are more sensitive to the effects of EDCs. Therefore, to address why endocrine disruption seems so widespread in fish, it is necessary to consider aspects of fish physiology and their environment that may increase their exposure to EDCs. Dependence on aquatic respiration, strategies for iono-osmotic regulation, and maternal transfer of contaminants to eggs creates additional avenues by which fish are exposed to EDCs. This paper provides an overview of responses observed in feral fish populations that have been attributed to EDCs and illustrates many of the factors that need consideration in evaluating the risks posed by these chemicals.

Challenges and opportunities with the use of biomarkers to predict reproductive impairment in fishes exposed to endocrine disrupting substances

Aquatic Toxicology, 2010

Biomarkers are commonly used as signposts to evaluate the potential of contaminants to disrupt the endocrine system. However, the relationship between responses in these biomarkers and whole organism endpoints that directly affect population status is not clearly understood. In this study, the relationship between egg production (a whole-organism endpoint which has been directly linked to population-level responses) and biomarkers (sex steroids, vitellogenin (VTG) and gonad size) is examined. Data were collected from short-term reproductive tests in which a wide variety of fish species were exposed to a suite of contaminants with known or unknown modes/mechanisms of action (MOA). The potential to use biomarkers as signposts was evaluated by determining the occurrence of false negatives (i.e., an effect in egg production was not accompanied by a biomarker response) and false positives (i.e., an effect in biomarkers was not followed by an effect in egg production). The quantitative relationships between biomarkers and egg production, and the ability to use these quantitative relationships to predict population-level responses based on modeling was also assessed. A suite of female biomarkers resulted in a relatively low occurrence of both false positives and negatives, indicating the potential for their use as signposts for reproductive effects via endocrine disruption. Egg production in short-term adult fish reproductive tests showed significant relationships to 17␤-estradiol (E 2 ), changes in female VTG levels, and relative female gonad size (gonadosomatic index; GSI). Weaker significant relationships were found between egg production and both VTG levels and GSI in males. However, use of these quantitative relationships to predict population-level effects are cautioned because of high levels of uncertainty. This study demonstrates that there are qualitative and quantitative relationships among biomarkers, regardless of fish species used or the MOA of contaminants and concludes that a suite of female reproductive biomarkers can be used as effective signposts to screen chemicals and assess waste streams for endocrine disrupting substances with different MOA.

Environmental effect assessment for sexual endocrine-disrupting chemicals: Fish testing strategy

Integrated Environmental Assessment and Management, 2010

Current standard testing and assessment tools are not designed to identify specific and biologically highly sensitive modes of action of chemicals, such as endocrine disruption. This information, however, can be important to define the relevant endpoints for an assessment and to characterize thresholds of their sublethal, population-relevant effects. Starting a decade ago, compound-specific risk assessment procedures were amended by specifically addressing endocrine-disrupting properties of substances. In 2002, the Conceptual Framework, agreed upon by OECD's Task Force on Endocrine Disrupters Testing and Assessment, did not propose specific testing strategies, and appropriate testing methods had not yet been developed and approved. In the meantime, the OECD Test Guidelines Programme has undertaken important steps to revise established and to develop new test methods, which can be used to identify and quantify effects of endocrine-disrupting chemicals on mammals, birds, amphibians, fish, and invertebrates. For fish testing of endocrine-disrupting chemicals, the first Test Guidelines have recently been adopted by the OECD and validation of further test systems is under progress. Based on these test systems and the experience gained during their validation procedures, we propose a 3-step fish testing strategy: 1) Weight-of-evidence approach for identifying potential sexual endocrine-disrupting chemicals; even after advanced specification of systematic criteria, this step of establishing initial suspicion will still require expert judgment; 2) in vivo evaluation of sexual endocrinedisrupting activity in fish by applying in vivo fish screening assays; sufficient data are available to diagnose the aromataseinhibition and estrogen-receptor agonist mechanisms of action by indicative endpoints (biomarkers), whereas the ability of the respective biomarkers in the screening assay to identify the estrogen-receptor antagonists and androgen-receptor agonists and antagonists requires further validation; 3) characterization of sexual endocrine-mediated adverse effects including threshold concentrations; in cases when the most sensitive population-relevant endpoints and the most sensitive time window for exposure are known for the mechanisms of action, the fish full life-cycle or 2-generation test, which are the normal definitive tests, might be abbreviated to, e.g., the fish sexual development test. In the European Union, the measurement of indicative endpoints in the definitive test might be crucial for the authorization procedure under REACH and plant-protection products. The results of the definitive tests can be used in existing schemes of compound-specific environmental risk assessments. Integr Environ Assess Manag 2010;6:653-662. ß 2010 SETAC