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Endocrine Disrupting Compounds:

General Overview and Impact on Freshwater Biology. Endocrine Disrupting Compounds:. Photo by Judy Gibson From: Jenkins et al ., 2009 P. SCAP Water Issues Committee Meeting May 5, 2011. All vertebrates possess an endocrine system which consists of Glands : Secrete hormones

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Endocrine Disrupting Compounds:

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  1. General Overview and Impact on Freshwater Biology Endocrine Disrupting Compounds: Photo by Judy Gibson From: Jenkins et al., 2009 P SCAP Water Issues Committee Meeting May 5, 2011

  2. All vertebrates possess an endocrine system which consists of • Glands: Secrete hormones • Receptors: Detect and react to hormones The Endocrine System

  3. All vertebrates possess an endocrine system which consists of • Glands: Secrete hormones • Receptors: Detect and react to hormones • The endocrine system is responsible for biochemical signals that insure proper function of the body throughout the life cycle. The Endocrine System

  4. All vertebrates possess an endocrine system which consists of • Glands: Secrete hormones • Receptors: Detect and react to hormones • The endocrine system is responsible for biochemical signals that insure proper function of the body throughout the life cycle. • Endocrine disrupting compounds (EDCs) mimic natural hormones and can bind with hormone receptors – disrupting normal endocrine function The Endocrine System 17b-Estradiol Natural hormone Nonylphenol Degradation product of nonionic surfactants (detergents)

  5. Exogenous Compounds-compounds (molecules) that originate outside of living organisms • Encompass a variety of chemical classes including pesticides, pharmaceuticals, plastisizers, flame retardents, hormones, cleaning products, personal care products • Many are organic wastewater contaminants (OWCs) and some are contaminants of emerging concern (CECs) • Primary focus has been on the EDCs “estrogenic effects”-where EDCs mimic the hormone estrogen • Estrogen receptors are essentially the same among most vertebrates Endocrine Disrupting Compounds

  6. EDCs Widespread in the Environment

  7. Primary release mechanisms: • Discharge from wastewater treatment plants (WWTPs)APEs, Hormones (e.g. EE2), Triclosan, BPA, Pharmaceuticals • Agricultural wastewater dischargesHormones • Urban and agricultural runoffPAHs, OCPs • Industrial dischargesAPEs, BPA, Phthalates EDC Release to Freshwater Systems

  8. Abnormally high incidence of intersex fish observed downstream from WWTPs in late 1970s Observations led to years of research to determine cause of abnormalities Field studies: Impacts on Freshwater Biology • Confirmed correlation between proximity to treated effluent and sexual disruption • Measured concentrations of EDCs in rivers and treated wastewater effluent-detected at parts per billion (mg/L) to parts per trillion (ng/L) Laboratory studies: • Examined estrogenic effects of individual EDCs on fish and other biota • Determined potency (i.e. estrogenic activity) of individual EDCs (e.g. EE2 found to cause feminization at 1.2 ng/L)

  9. Evidence of sexual disruption includes: • Possession of both male and female germ cells • Males in possession of “female-like” gonadal tissue and reproductive ducts • Increased levels of female-specific protein vitellogenin (VTG) • Reduced sperm density Impacts on Freshwater Biology Rodgers-Gray et al. 2001

  10. Evidence of sexual disruption includes: • Possession of both male and female germ cells • Males in possession of “female-like” gonadal tissue and reproductive ducts • Increased levels of female-specific protein vitellogenin (VTG) • Reduced sperm density Impacts on Freshwater Biology Exposure of juvenile wild roach to sewage treatment water effluent (STWE) of various dilutions resulted in dose-dependent and sustained feminization of reproductive ducts in males Many EDCs bioconcentration in higher trophic level organisms such as fish, allowing for exposure even when aqueous concentrations are very low Rodgers-Gray et al. 2001

  11. The impact of individual EDCs is primarily a function of the compound’s chemical properties and the extent of its use in human activity Factors To Consider: • Aqueous concentration • Partition (i.e. does it prefer to sorb into sediments or does it remain in the aqueous phase?) • Degree of bioconcentration • Estrogenic activity • Degradation pathways Impacts on Freshwater Biota Bisphenol-A Possible treatment options will also depend on chemical properties DDT

  12. Comparison of Common EDCs: Factors Effecting EDCs’ Biological Impact

  13. Issue: To what extent to EDCs in the SAR impact the reproductive ability of the Santa Ana Sucker Recent studies from the SAR basin provide insight into this issue: EDCs in the Santa Ana River • Gross et al., 2004: • Measured concentrations of OWCs including APEs and EE2 in effluent of four WWTPs and in river water along the SAR. • APE metabolites detected in all effluents/at all locations-max concentrations of 19.6 parts per billion (mg/L) in effluent upstream of Prado Dam • EE2 not detected in river or effluent water at detection limit of 2 parts per trillion (ng/L) • Significant downstream attenuation of compounds observed

  14. Issue: To what extent to EDCs in the SAR impact the reproductive ability of the Santa Ana Sucker Recent studies from the SAR basin provide insight into this issue: EDCs in the Santa Ana River • Jenkins et al., 2009: • Detected OWCs, including EDCs, in aquatic biota and water in the SAR basin along a gradient of proximity to WWTP effluent (including one control site). • Conducted in vitro assays of sexual parameters of western mosquitofish (proxy for santaana sucker) • Results indicate endocrine disruption in the form of altered hormone ratios in both sexes and secondary sex characteristics in males

  15. EDCs are exogenous compounds that encompass a variety of chemical classes and derive from numerous areas of human activity • Mimic hormones, in particular estrogen, and bind to endocrine receptors thereby interfering with normal endocrine function • Treated effluent is an important conduit of EDCs to the environment • Fate, transport and biological impact is a function of chemical properties and extent of human use • Large body of evidence that exposure to EDCs causes endocrine disruption in riverine fish, including mosquito fish in the Santa Ana River • On-going research further investigates link between EDCs and reproductive impairment in aquatic biota Summary

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