Endocrine Disrupting Compounds General Overview and Impact on

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

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

The Endocrine System • 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 • 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 17 b-Estradiol Natural hormone Nonylphenol Degradation product of nonionic surfactants (detergents)

Endocrine Disrupting Compounds • 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

EDCs Widespread in the Environment EDC Common Use Alkylphenol ethoxylates (APEs) and their degradation products Industrial and household nonionic surfactants (detergents) Bisphenol-A (BPA) Most widely used plasticizer (softener) in the US 17 a-ethynyl estradiol (EE 2) Synthetic estrogen used in most birth control and hormone replacement drugs Organochloride pesticides (OCPs) Pesticides, herbicides and fungicides used by industry and household consumers (ex: DDT)-banned since Phthalates Ubiquitous component of leachable plastics Polyaromatic hydrocarbons (PAHs) Nonvolatile hydrocarbons present in oils and petroleum-based lubricants Polychlorinated biphenyls (PCBs) Oils used primarily in transformers (ex: Aroclor)-banned since 1976 Triclosan and degradation products Common ingredient of soaps and personal/household disinfectants

EDC Release to Freshwater Systems Primary release mechanisms: • Discharge from wastewater treatment plants (WWTPs) APEs, Hormones (e. g. EE 2), Triclosan, BPA, Pharmaceuticals • Agricultural wastewater discharges Hormones • Urban and agricultural runoff PAHs, OCPs • Industrial discharges APEs, BPA, Phthalates

Impacts on Freshwater Biology Abnormally high incidence of intersex fish observed downstream from WWTPs in late 1970 s Observations led to years of research to determine cause of abnormalities Field studies: • Confirmed correlation between proximity to treated effluent and sexual disruption • Measured concentrations of EDCs in rivers and treated wastewater effluentdetected 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. EE 2 found to cause feminization at 1. 2 ng/L)

Impacts on Freshwater Biology 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 Rodgers-Gray et al. 2001

Impacts on Freshwater Biology 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 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

Impacts on Freshwater Biota 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 Bisphenol-A • Estrogenic activity • Degradation pathways Possible treatment options will also depend on chemical properties DDT

Factors Effecting EDCs’ Biological Impact Comparison of Common EDCs: EDC Sorption Degradation Bio-concentration Estrogenic Activity Possible Treatment Options APEs Moderate Bio-aerobic & anaerobic Moderate High Sorption, oxidation, reduction BPA Moderate Bio-aerobic & Photo Moderate High Biodeg. Photodeg. EE 2 Strong Bio-aerobic Strong Very High Sorption, Oxidation OCPs Moderate Bio & Photo are minimal Very Strong Low to Moderate Sorption, Photodeg. Oxidation Phthaltes Weak Bio-aerobic Weak Moderate Biodeg. , Oxidation PAHs Strong Bio-aerobic & Photo Highly Variable Moderate to High Sorption, Oxidation PCBs Strong Bio & Photo are minimal Strong Moderate to High Sorption, Photodeg. Oxidation Triclosan Moderate Photo, Bio is disputed Dioxin biproducts strongly bioconcentrate Moderate (for Dioxins + Furans) Sorption, Oxidation, Possibly Reduction

EDCs in the Santa Ana River 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: Gross et al. , 2004: • Measured concentrations of OWCs including APEs and EE 2 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 • EE 2 not detected in river or effluent water at detection limit of 2 parts per trillion (ng/L) • Significant downstream attenuation of compounds observed

EDCs in the Santa Ana River 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: 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 santa ana sucker) • Results indicate endocrine disruption in the form of altered hormone ratios in both sexes and secondary sex characteristics in males

Summary • 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