The ABC's of EDCs: Endocrine Disrupting Chemicals in the Environment
David Quanrud
Phoenix, ArizonaJune 5, 2007
Water Resources Research Center 2007 Water Conference
What is an endocrine disrupting compound?
“An endocrine disruptor is an exogenous substance or mixture that alters function(s) of the endocrine system and consequently causes adverse health effects in an intact organism, or its progeny….”
From: “Global Assessment of the State-of-the-Science of Endocrine Disruptors.” International Programme on Chemical Safety, World Health Organization (2002).
Documented effects of EDCs in wildlife
• Adverse effects on fish development and reproduction
• Eggshell thinning in birds of prey
• Alligator population decline in a polluted lake (FL)
• Development of male sex organs in female marine animals such as whelks and snails
Denver Post (September 6, 2006)
EDCs in the News
EDC effects at the population scale• Field study at Canadian research lake, Ontario• Fathead minnow population collapsed after two years of estrogen addition
Kidd et al. 2007: Proceedings of the National Academy of Sciences
Speculated effects of EDCs in humans
• Reductions in male fertility and declines in the numbers of males born
• Abnormalities in male reproductive organs
• Female reproductive diseases including fertility problems, early puberty, and early reproductive senescence
• Increases in mammary, ovarian, and prostate cancers
How do endocrine disrupting compounds act?
• reduce hormone production in endocrine glands
• mimic or counteract hormones at target tissues
The USEPA has identified three important categories of EDCs
– Estrogenic
– Androgenic
– Thyroid active
Examples of known EDCs in wastewater
• Natural hormones (estrogens)– Estradiol– Estrone– Estriol
• Synthetic compounds– Ethinyl estradiol (birth control pill)– Alkylphenols, e.g. nonylphenol (surfactant byproduct)– Bisphenol A (polycarbonate plastic) – PBDEs (flame retardant; partially phased out)
AZ Daily Star (March 18, 2007)
EDCs in the News
Bisphenol A – Ingredient in polycarbonate plastic, epoxy resin– Water bottles, CDs, epoxy lining in metal cans – Controversial: some studies find low dose
estrogenic effects, other studies do not
Question:
How can we measure estrogenic compounds in environmental samples?
• Individual chemical measurements
• Collective measurement using bioassaysTotal estrogenic activity
Yeast estrogen screen (YES) bioassay
17-α Ethinylestradiol
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
1.E-13 1.E-12 1.E-11 1.E-10 1.E-09 1.E-08 1.E-07 1.E-06
Molar concentration in well
A 570
nm -
A 630
nm
EC50=1.1 x 10-10 M
Cytoplasm
E
R
R E
E
Cytoplasm
= Receptor
R
hER β-gal
CPRGyellow
CPRGred
lac-z
RE
=Estrogens
Cytoplasm
RR
RR EE
EE
Cytoplasm
= Receptor
RR
hER β-gal
CPRGyellow
CPRGred
lac-z
RE
RREE
=Estrogen
Oxidation ditch
Membrane bioreactor
Nitrification/denitrification
Activated Sludge (pure O2 )
Biotower #1
Biotower #2 (longer SRT)
Estrogenic Activity: Comparison of six Arizona WWTPs
Influent
Effluent
Sludge
Preliminary Comparison of six Arizona WWTPs
2° Clarifier
FinalSludge
Bar Screen
Raw Influent Oxidation Ditch
Sludge Drying Beds
2° Sludge(WAS)
Final Effluent to Storage Pond
(RAS)
Chlori-nation
Sludge Holding Tanks
2° Clarifier
FinalSludge
Bar Screen
Raw Influent Oxidation Ditch
Sludge Drying Beds
2° Sludge(WAS)
Final Effluent to Storage Pond
(RAS)
Chlori-nation
Sludge Holding Tanks
Oxidation ditch Membrane bioreactor
2° Sludge2° Sludge(WAS)(WAS)
RAS
RawRawInfluentInfluent
Bar ScreenBar ScreenGritGrit
ChamberChamber
1° Clarifier1° Clarifier AerationAeration 2° Clarifier2° Clarifier
1° Clarifier Sludge1° Clarifier Sludge
Final Final Filter/UVFilter/UV
SludgeSludge
DenitrifiDenitrifi--cationcation
Final Final Effluent Effluent
2° Sludge2° Sludge(WAS)(WAS)
RAS
RawRawInfluentInfluent
Bar ScreenBar ScreenGritGrit
ChamberChamber
1° Clarifier1° Clarifier AerationAeration 2° Clarifier2° Clarifier
1° Clarifier Sludge1° Clarifier Sludge
Final Final Filter/UVFilter/UV
SludgeSludge
DenitrifiDenitrifi--cationcation
Final Final Effluent Effluent
Nitrification/denitrification
DigesterSupernatant
2° Clarifier
AnaerobicDigestedSludge
1° SludgeBar Screen
Thickener Effluent
RawInfluent 1° Clarifier
Trickling Filters
Thickener #3Thickener #3
2° Sludge
(WAS)
Thickener #2Thickener #2
Final Effluent
DigesterSupernatant
2° Clarifier
AnaerobicDigestedSludge
1° SludgeBar Screen
Thickener Effluent
RawInfluent 1° Clarifier
Trickling Filters
Thickener #3Thickener #3
2° Sludge
(WAS)
Thickener #2Thickener #2
Final Effluent
Biotower #1
DigesterSupernatant
2° Clarifier
AnaerobicDigestedSludge
1° SludgeBar ScreenBar ScreenGrit ChamberGrit Chamber
Thickener Effluent
RawInfluent 1° Clarifier1° Clarifier
Activated Sludge
Thickener #3Thickener #3
2° Sludge 2° Sludge (WAS)(WAS)
Thickener #2Thickener #2
RAS
Final Effluent
DigesterSupernatant
2° Clarifier
AnaerobicDigestedSludge
1° SludgeBar ScreenBar ScreenGrit ChamberGrit Chamber
Thickener Effluent
RawInfluent 1° Clarifier1° Clarifier
Activated Sludge
Thickener #3Thickener #3
2° Sludge 2° Sludge (WAS)(WAS)
Thickener #2Thickener #2
RAS
Final Effluent
Activated sludge
RawRawInfluentInfluent
Bar ScreenBar ScreenGrit Grit ChamberChamber
1° Clarifier1° Clarifier BiotowersBiotowers 2°2° ClarClar
Anaerobic Anaerobic DigesterDigester
1° Clarifier Sludge1° Clarifier Sludge
Digested Sludge to Digested Sludge to Storage BasinsStorage Basins
ChlorChlor//DechlorDechlor
WASWAS
3° Filters3° Filters
Final Final EffluentEffluent
3° Filter Backwash3° Filter Backwash
Sludge Sludge
RAS
RawRawInfluentInfluent
Bar ScreenBar ScreenGrit Grit ChamberChamber
1° Clarifier1° Clarifier BiotowersBiotowers 2°2° ClarClar
Anaerobic Anaerobic DigesterDigester
1° Clarifier Sludge1° Clarifier Sludge
Digested Sludge to Digested Sludge to Storage BasinsStorage Basins
ChlorChlor//DechlorDechlor
WASWAS
3° Filters3° Filters
Final Final EffluentEffluent
3° Filter Backwash3° Filter Backwash
Sludge Sludge
RAS
Biotower #2
Overall estrogenic activity removal (%)
2665
99
54
97 9798 98
Influent to effluent estrogenic activity removal (%)
3171
99
85
Influent
Effluent
Sludge
Influent
Effluent
Sludge
Summary1.EDCs include estrogens, androgens, and
thyroid active compounds
2.Removal of estrogenic activity during wastewater treatment is dependent on process selection/efficiency
3.There is a lot we don’t know about a lot of trace organics in wastewater
The ABC's of EDCs: Endocrine Disrupting Chemicals in the Environment What is an endocrine disrupting compound?Documented effects of EDCs in wildlifeEDCs in the NewsEDC effects at the population scaleSpeculated effects of EDCs in humansHow do endocrine disrupting compounds act?The USEPA has identified three important categories of EDCsExamples of known EDCs in wastewaterAZ Daily Star (March 18, 2007)Slide Number 11Slide Number 12Yeast estrogen screen (YES) bioassaySlide Number 14Preliminary Comparison of six Arizona WWTPsSummary