Published on March 16, 2009
Advanced Ecology PCB 5046 March 18, 2008 Emerging Contaminants Endocrine Disrupting Compounds Professor J.J. Delfino Environmental Engineering Sciences Emerging Contaminants (ECs) and Endocrine Disruptor Compounds (EDCs) The scientific community has been investigating ECs and EDCs for several years in an attempt to better understand their significance in ecosystems Pharmaceuticals a.k.a. PPCPs We, as a society, need to be aware of the impacts of these compounds on aquatic life and ultimately in drinking water supplies 1
EDCs & ECs = PPCPs & Pesticides • EDCs = Endocrine Disruptor Compounds • ECs = Emerging Contaminants • Many pharmaceuticals, personal care products.. PPCPs.. (and some pesticides) show endocrine disruption characteristics • We’ve had many “alerts” up to now; for example: • Silent Spring (1962) • Our Stolen Future (1996) • Kolpin et al. (2002) • ES&T 40 (2006) What is an endocrine disruptor? • Exogenous chemical substance or mixture • Alters structure or function of the endocrine system • Causes adverse effects at the organism level – Interferes with the production, release, transport, metabolism of natural hormones in the body • And, in the organism’s progeny, populations or subpopulations • EDC status is based on scientific principles, data, weight of evidence and the precautionary principle USEPA 1998 Recent Cover Story on Pharmaceuticals in the Environment C&E News, February 25, 2008 2
Fish and Aquatic Life are Highly Susceptible to ECs and EDCs in Water • It is presently unclear as to the long term implications of PPCPs on aquatic life and ecosystem integrity – but early signs are not encouraging, especially in terms of affecting reproductive success Depending on the source, different chemicals are entering the environment with potentially serious ecological impacts Pharmaceuticals are the ECs and EDCs of popular choice right now, but they aren’t the only compounds of concern – even though their sources to the environment are numerous Aquatic organisms are constantly exposed to PPCPs, making them the unwilling subjects in an unintentional global experiment Gainesville Sun 3/11/08 • Fish have been found to have lower sperm counts and damaged sperm • Male fish have become feminized with the appearance of an egg cell protein in their blood • Female fish have developed male-like genital organs • Some populations have mainly females and very few males 3
In addition to ecological concerns, ECs and EDCs in drinking water have created much recent public interest Gainesville Sun, March 10, 2008 The Gainesville Sun has taken an editorial interest in this topic March 12, 2008 GRU Claims that Gainesville’s Drinking Water is Safe Gainesville Sun, March 14, 2008 • As it turns out, GRU has not tested Gainesville’s drinking water but it is “confident” that the drinking water supply is free of pharmaceuticals…” • Should they be confident without testing? 4
Plasticizing Agents such as Bisphenol A (BPA) have been implicated as EDCs Concern over the leaching of BPA from plastic baby bottles has led to a return to the glass baby bottle design of past generations Endocrine systems • Glands which secrete minute quantities of hormones and other substances into the blood to influence remote tissues and other glands ENDOCRINE NERVOUS IMMUNE EDCs can impact multiple sites in humans 5
Endocrine Disruptor Reacting with Receptors Intracellular Hormone Pathway MAJOR GLANDS AND REPRESENTATIVE HORMONES AND EFFECTS GLANDS HORMONES EFFECTS Pituitary LH, FSH, Growth Protein synthesis, growth Hormone, Prolactin Testes Testosterone Male development, behavior, maturation, spermatogenesis Ovaries Estrogens Sexual maturation, egg development Adrenal Androgens, estrogens, Sodium balance, water balance, aldersterone, epinephrine, metabolism, stress response, steroids norepinephrine, dopamine from cholesterol Pancreas Insulin, glucagon, Circadian rhythms, blood sugar somatostatin Hypothalamus FSH, somatostatin, and Regulates circulating levels of hormones, many more body temperature, emotions, behavior, fat deposition, sexual activity Thyroid Thyroxine Development, growth, metabolism, reproduction 6
Early EDC Findings AGENT/SOURCE SYSTEM A FEW DETAILS EFFECTED Diethylstilbestrol Reproductive Cancer in offspring of women who took DES (DES) during pregnancy; estrogen-like activity in animals and in vitro tests DTT/DDE Reproductive Eggshell thinning leading to population declines in predatory birds; weak estrogen effects in the laboratory PCBs Neurological Behavioral aberrations in birds eating fish from industrially-polluted Great Lakes; Reproductive reproductive failure in minks, seals, and birds after eating PCB-contaminated fish; impaired neurological and intellectual development in children after accidental poisoning (Japan), and in children of mothers who ate PCB- contaminated Great Lakes fish (1970s) PCBs and Dioxin Immunological Perturbed immune function in humans after (TCDD) accidental poisoning (Japan); early mortality and reproductive failure in trout in industrially- polluted Great Lakes AGENT/SOURCE SYSTEM A FEW DETAILS EFFECTED Paper mill effluent Reproductive Imposex: estrogen-like masculinization of female fish—worldwide reports Wastewater Reproductive Vitellogenin: egg sac protein production in male fish treatment plant —worldwide reports effluent Emerging Contaminants (ECs) “Up and Coming or Newly Rediscovered?” • “Up and coming” chemical and biological contaminants [i.e. “newly discovered or recently re-discovered”] • Focus of special issue of ES&T 40, December 1, 2006 (Editorial: Field et al.,p.7105) • Stimulus – better analytical methods for organic contaminants [especially polar organics] and biological agents • The polar organic contaminants can be analyzed via LC-tandem MS 7
More on Emerging Contaminants • EC status depends on longevity in environment, toxicology, etc. • Question: “Is the EC an EDC or re- emergent well known contaminant from the past?” • Human health status and ecological effects may require long term research • An EC may be “emerging” for years until better understood or new status attached “A Re-emergent EC that is an EDC” DDT’s persistent progeny: DDE The Issue “EDCs and ECs [PPCPs] are ubiquitous in our environment because of their seemingly endless number of uses and origins in domestic, industrial and agricultural applications.” WEFTEC Update, Summer 2006 8
PPCPs Pharmaceuticals (P): chemicals used for diagnosis, treatment, alteration, and prevention of disease or function of the human body (includes veterinary and elicit drugs) Personal Care Products (PCPs): cosmetics, sunscreens, personal hygiene, nutritional supplements and many others Pesticides (also = P): chemicals used to control pest populations Categories of PPCPs found in various aquatic systems Personal Care Products (PCPs) Pharmaceuticals (P) Applications Modes of action – Fragrances – Antibiotics – Lotions – Pain killers – Sun-screens – Anti-depressants – Shampoos – Tranquilizers – Cleaning Products – Birth control – Others – Others Pharmaceutical Sources • Industries • Hospitals • Disposal of unused formulations • Pets/Farm animals • Human excreta 9
Personal Care Product Sources ES&T 40, October 15, 2006 Washing products for – Hair – Skin – Mouth Lotions Extraction/Detection • Solid Phase Extraction Add Acid to sample – Extracts analytes onto solid phase and then are dissolved into a solution SPE Cartridge Sample • LC/MS • Antibiotics, Anti- MeOH depressants, analgesics, stimulants To LC/MS 10
Extraction/Detection • Continuous Liquid- Liquid Extraction – Extracts analytes into solvent (methylene chloride, CH2Cl2) • GC/MS • Plasticizers, fragrances, deodorizers, anti- corrosives, insecticides, steroids, hormones PPCPs in U.S. Streams • One or more of 95 substances were found in 80% of 139 streams during 1999-2000 [Kolpin et al (USGS),ES&T 36 (2002) • PPCPs ranged from BDL/ BRL to ca. 1µg/L median concentration • Broad range of chemicals including human and veterinary antibiotics, Rx and non-Rx drugs, steroids and hormones and organic wastewater contaminants (OWCs) 11
PPCPs and Wastewater Treatment • Incomplete removal observed for PPCPs from wastewaters, varying between 20-90%, depending on type of compound • Removal attributed to biodegradation as well as adsorption onto solids • The observed biological removal varies strongly from compound to compound, with no evident correlation to compound structure PPCPs in surface waters may impact the trend toward more water re-use • The presence of PPCPs in surface waters indicates that these compounds are acting as “tracers” for the presence of treated sewage discharges and untreated animal wastes • The presence of these chemicals in drinking water taken from surface waters should convince citizens that they are drinking treated wastewater – as much as they may not want to admit this very much 12
Are PPCPs a Threat to Human Health? Some scientists (perhaps a minority view right now) believe these compounds pose no threat to humans or the environment Others point out that synergistic and long- term effects of these chemicals aren’t understood Keep in mind, pharmaceuticals are designed to be bioactive Two Possible Threats • Drugs potentially causing endocrine disruption • Potential for disease- causing bacteria to become immune Pharmaceutical Use Will continue to rise for several reasons: – Expanding uses for drugs – Increasing per capita consumption – Increasing population – Expiration of patents – Government subsidies for lower income patients, etc. 13
Top Sales While the KNOWN universe of chemicals might seem large (26 million), the universe of POTENTIAL chemicals (those that could possibly be synthesized and those that already exist but which have not yet been identified) is unimaginably large. How many distinct organic chemical entities could hypothetically be synthesized and added to a seemingly limitless, ever-expanding chemical universe? By limiting synthesis strictly to combinations of 30 atoms of just C, N, O, or S, more than 1060 structures are possible ! Expanding the allowable elements to other heteroatoms (e.g., P and halogens), the number of possible structures becomes enormous. 14
Einstein on: Environmental Monitoring “Not everything that can be counted counts, and not everything that counts can be counted.“ (oft attributed to Albert Einstein) corollary for environmental monitoring Not everything that can be measured is worth measuring, and not everything worth measuring is measurable. Types of PPCPs • Antibiotics • Endocrine Disruptors – Steroids • Estrogen • Testosterone • Analgesics (pain killers) • Antidepressants • Personal Care Products Antibiotics • Beta-lactam – Amoxicillin • Macrolide • Sulfonamide Tetracycline • Fluoroquinolone Macrolide – Cipro • Tetracycline Sulfonamide Amoxicillin Cipro 15
Estrogens • Different types Natural • E1 Estrone • E2 17-β-Estradiol • EE2 17-α-Ethynylestradiol Analgesics • Painkillers typically have anti-inflammatory and anti-fever effects – Acetaminophen – Ibuprofen – Codeine – Diclofenac – Hydrocodone – Naproxen Anti-Depressants • Paxil – 9th ranked highest sales in U.S. in 2002 • Prozac • Zoloft • Celexa 16
Effects of an Anti-Depressant • Prozac’s active ingredient Fluoxetine causes – Delayed sexual development in mosquito fish – Delayed metamorphosis in frogs Types of Personal Care Products • Caffeine • Anti-bacterials (Triclosan) • Musks • Sunscreens • Deodorizers • Preservatives • Herbal remedies Effects of other ECs and EDCs • Caffeine causes hyperactivity in aquatic life • Antiseptics/disinfectants can promote anti- biotic resistant bacteria • Musks have been found to be toxic • Sunscreens have been found to bioaccumulate • Certain preservatives have weak estrogenic activity 17
Upgrades to Wastewater Treatment Systems to Improve PPCP Removal • Ozone • Activated Carbon • Δ Hydraulic Retention Time • Reverse Osmosis • UV photolysis using titanium dioxide catalyst Catalyst Offers Hope for Managing EDCs February 6, 2008 Researchers report effectiveness of a powerful, environmentally friendly catalyst in destruction of various estrogens that escape complete removal in wastewater treatment plants. Their study is scheduled for the Feb. 15 issue of the American Chemical Society's Environmental Science & Technology, a semi-monthly journal. In the new study, Nancy W. Shappell and colleagues explain that endocrine disruptors, both natural hormones and hormone-like compounds, have been detected in the surface waters. Many of these endocrine disruptors have estrogenic activity. To address this problem, the researchers tested a new catalyst called Fe-TAML or Fe- B*. In the presence of hydrogen peroxide, the catalyst quickly and effectively destroyed various forms of estrogens typically found in post-treatment wastewater, removing 95 percent of the chemicals — including Ethinylestradiol — in 15 minutes. Estrogenic activity was diminished to a similar extent. Further research will evaluate Fe-B*'s efficacy on actual wastewater, in addition to more extensive evaluation of byproduct toxicities. Usefulness in wastewater treatment could be doubly beneficial, as Fe- B* has been reported to destroy harmful bacterial Endocrine disruption hypothesis proponent • Great Lakes studies – Affected wildlife species were top predators – ECs and EDCs in the environment bioaccumulated and biomagnified up food chain – Problems usually in offspring, not adults • Early Hypothesis: potential effects-cancer, and impacts on reproductive, immunological, and/or neurological systems Theodora Colborn related by endocrine system Courtesy CNN 18
Theo Colborn, PhD • THEO COLBORN is a Professor of Zoology at the University of Florida, Gainesvillle and President of The Endocrine Disruption Exchange, (TEDX, Inc), Paonia, CO. She is the author of numerous scientific publications about compounds that interfere with hormones and other chemical messengers that control development in wildlife and humans. She edited Chemically Induced Alterations in Sexual and Functional Development: The Wildlife/Human Connection, published in 1992. The information from this volume and numerous subsequent scientific publications was popularized in her 1996 book, Our Stolen Future, co-authored with Dianne Dumanoski and J. Peterson Myers now published in eighteen languages. Dr. Colborn's work has prompted the enactment of new laws around the world and redirected the research of academicians, governments, and the private sector. • http://www.endocrinedisruption.com Early Evidence of Scientific Concern The 1991 Wingspread Conference • The conferees consensus: – Huge quantities of chemicals are entering waters; some may be EDCs – Effects in laboratory tests at levels approaching those in the aquatic environment – Embryos and the young are especially vulnerable - effects may not be seen until later stages of maturity – There is a potential for population effects in humans and wildlife Endocrine disrupter hypothesis Two aspects of the hypothesis: • Has the mode of action proposed (endocrine disruption) been shown to be the cause of the effects seen? • Have low levels of contaminants in the environment been linked to human health effects? 19
Status of the EDC hypothesis • Since the 1991 Wingspread Conference, and hundreds of studies performed subsequently, there is still very little compelling evidence that low environmental levels of EDCs (i.e. those not related to spills or sources/areas of high pollution) put human populations at risk (fish and wildlife are another story) – National Academy of Sciences (1999) – World Health Organization, 2002 – EPA, 2002 – SCOPE/IUPAC, 2003 – Published reviews in scientific journals Our Stolen Future Courtesy of EDCs and ECs? • Our Stolen Future by Theo Colborn, et al. (1996) • Widely reviewed in the popular and scientific press • Gave major boost to EC and EDC concerns Congressional Actions • 1996-Congress passed the Food Quality Protection Act – Designed to establish safe pesticide levels in foods mainly to protect children’s health – Attached mandate for EPA to look for estrogenic compounds in the environment which may effect human health • Safe Drinking Water Act Amendment 1996- Congress amends the SDWA and directs EPA to screen for estrogenic substances in drinking water 20
EDC modes of action • Mimic natural hormone (e.g. bind at receptor) • Inhibit action of natural hormone (e.g. receptor binding inhibition) • Interfere with gene expression (e.g. exposure in utero leads to changes in offspring) • Enzyme inhibition (e.g. steroid biosynthesis) Structure of well-characterized “emerged” presumptive EDCs DIOXIN (TCDD) 1 of 209 PCBs Tributyltin (TBT) Diethylstilbestrol (DES) DDE ? Endocrine disrupters in the environment – Water Reports of effects with unidentified – Plastics causes in humans: – Food – Declining sperm counts – Personal care items – Increased breast and testicular – Pharmaceuticals cancer – Aggressive behavior/ intellectual diminishment – Birth defects – Juvenile obesity 21
EDC fetal exposure may lead to obesity source: Prof. F. vom Saal, Univ. Missouri pres. To AAAS Meeting, SF, CA Feb 2007 Human health effects • Human sperm counts & sperm quality – Regional declines/increases/static – Possible overall decline – Weak relationship to endocrine disruption – Numerous reviews, studies, since Wingspread – No decline in fertility in most cases – Other potential causes in developed countries (diet, stress, age, medical practices) – Animal models support plausibility of endocrine disruption model, but not direct link Human health effects • Breast cancer – Natural estrogen known to increase risk – 50% of breast cancers not estrogen-sensitive – Moderately good evidence that breast cancer rates have increased – Weak evidence that increase is endocrine disrupter-related: – Results of several studies • DDT/DDE: no correlation • PCBs: no correlation • Organochlorides: no correlation • Dieldrin: some increase in risk/highest levels • Dioxin: no correlation (small sample size) 22
Human health effects • Immune function – PCBs and dioxin (TCDD) perturb immune function – Poisonings caused effect in children and adults • Increase in respiratory symptoms and infectious diseases, suppression of allergies – Attributed to thyroid atrophy, not endocrine disruption Human health effects • Neurobehavioral effects – PCBs likely disrupters of thyroid function in utero • Mass poisonings Japan 1968, Taiwan 1979 • Great Lakes fish-eaters 1960-1970s – No detectable effects at low levels – Retardation, growth and movement disorders, attention Human health effects • Phthalates – Used to make plastics more flexible – Not bonded to structure so can leach – Some plastics are 40% phthalates – If plastic smells sweet, those are the phthalates – Body burden in humans (serum and urine) higher than expected (CDC) 23
Human health effects • Phthalates rapidly metabolized and excreted • Male reproductive effects – 2005 study was most comprehensive to date • Anti-androgen effect in utero • AGD (anogenital distance) as marker • AGD phthalate dose-dependent • Mimics phthalate syndrome in rats • Testicular dysgenesis syndrome: risk factors Sources of human exposure Phthalates • Vinyl flooring • Adhesives • Detergents • Lubricating oils • Food packaging • Automotive plastics • PCPs: Soaps, shampoos, hair spray, nail polish • PVC products: plastic bags, garden hoses, toys, blood- storage containers, some pharmaceutical and pesticide products • 1999-Banned from pacifiers, soft rattles and teething rings Baby products may cause health issues Gnv Sun, February 4, 2008, p. 7A • Study found link between phthalates in baby products and reproductive problems • Baby shampoos, lotions and powders contain phthalates • Use included stabilizing fragrances and making plastics flexible • Found in baby products • May cause reproductive problems in children at later age 24
Human health effects • Testicular cancer (most common cancer in young men age 25-34) – Increasing in developed countries since 1920 – No epidemiological studies of incidence and chemical exposure to date (2005) – No animal model Sources of human exposure • Low level sources/little or unknown concern – Air—unknown – Drinking water (municipal) —if treated, not a major concern – Soil and sediment—not a major concern for humans unless ground water is affected or fish are affected – Personal care products—unknown risk from direct use as specified by manufacturers • Skin absorption of ingredients • Inhalation of constituents Water Resources Implications • Potential impact on drinking water supplies – require more (expensive) treatment strategies • Potential impact on surface waters – ecosystem alteration due to aquatic life alterations • Potential impact on soil and ground water from land application of bio-solids (sludge and manure) of human and animal origin 25
Significance of EDCs • Corporations making, using, discharging ECs and EDCs need to stay informed of scientific developments in this field • Federal and state regulatory agencies are considering a response to the scientific findings but have not issued any proposed regulations specifically targeting EDCs separate from other regulations that might include them as part of earlier environmental legislation • Future regulatory actions could have a significant economic impact on corporations that are “involved” with EDCs • Ecosystem health, human health, and corporate environmental responsibility are inter-twined in this issue Summary • Endocrine disruption is a proven mode of action of some chemicals toward some species • Evidence is still weak for environmental low level effects in humans but these remain possible • PCBs and DES human adverse effects are likely attributable to endocrine disruption • Wildlife species have been most affected to date • Continued vigilance, monitoring and more research is clearly warranted • Regulatory response is under development 26
Acknowledgments Thanks to the following EES students at UF for some of the foregoing slides based on class assignments and graduate research projects: Heather Byrne Ryan McKenna Joseph Emery Dr.Brian Quinn Judd Larson Kristine Switt and others … and selected slides made available from Dr. Christian Daughton (EPA) References • Joss, A., Keller, E., Alder, A.C., et al. (2005). “Removal of pharmaceuticals and fragrances in biological wastewater treatment.” Water Research, 39(14):3139-3152. • U.S. Environmental Protection Agency. “PPCPs as Environmental Pollutants—Frequently Asked Questions from the Public, Media, and Scientific Communities.” Jun. 2001. <http:// epa.gov/nerlesd1/chemistry/pharma/faq.htm#disposal> • Arizona Water Resource. “Pharmaceuticals in Our Water Supplies.” Aug. 2000. <http://ag.arizona.edu/AZWATER/awr/july00/feature1.htm> • Kolpin, D.W., Furlong, E.T., Meyer, M.T., et al. (2002). “Pharmaceuticals, Hormones, and Other Organic Wastewater Contaminants in U.S. Streams, 1999-2000: A National Reconnaissance.” Environmental Science and Technology, 36:1202-1211. • Zimmerman, M.J. (2005). “Occurrence of Organic Wastewater Contaminants, Pharmaceuticals, and Other Personal Care Products in Selected Water Supplies, Cape Cod, Massachusetts, June 2004.” U.S. Geological Survey Open-File Report 2005-1206. • Daughton, C.G. quot;Pharmaceuticals in the Environment: Overarching Issues and Overview,quot; in Pharmaceuticals and Personal Care Products in the Environment: Scientific and Regulatory Issues, Daughton, C.G. and Jones-Lepp, T. (eds.), Symposium Series 791; American Chemical Society: Washington, D.C., 2001, pp. 2-38. References • Carballa, M., Omil, F., Lema, J.M., et al. (2004). “Behavior of pharmaceuticals, cosmetics, and hormones in a sewage treatment plant.” Water Research, 38(12):2918-2926 • American Water Works Association. “On Point: PPCPs—Pharmaceuticals and Personal Care Products in Drinking Water.” Apr. 2005. <http://www.awwa.org/Advocacy/YourWater/Issues/ OnPoint_PPCPs.cfm> • Environmental Science & Engineering. “When Pharmaceuticals Arrive at the Tap.” Mar. 2003. <http://www.esemag.com/0303/pharma.html> • Pinkston, K.E., Sedlak, D.L. (2004). “Transformation of Aromatic Ether and Amine-Containing Pharmaceuticals during Chlorine Disinfection.” Environmental Science and Technology, 38:4019-4025. • Huggett, D.B., Khan, I.A., et al. (2002). “Determination of beta-adrenergic receptor blocking pharmaceuticals in United States wastewater effluent.” Environmental Pollution, 121:199-205. • Lindberg, R.H., Wennberg, P., Johansson, M.I., et al. (2005). “Screening of Human Antibiotic Substances and Determination of Weekly Mass Flows in Five Sewage Treatment Plants in Sweden.” Environmental Science and Technology, 39(10):3421-3428. • Environment News Service. “Common Synthetic Fragrances Found to Harm Wildlife, Humans.” Nov. 2004. <http://www.ens-newswire.com/ens/nov2004/2004-11-01-01.asp> 27
Wealth of other materials and links to most of the ongoing work relevant to this topic are available at the U.S. EPA’s PPCPs Web Site: http://www.epa.gov/nerlesd1/ chemistry/pharma 28
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