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Endocrine Disruptors

Endocrine Disruptors

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Endocrine Disruptors

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  1. Endocrine Disruptors Alvin Stein, MD ½ Hour AMA PRA Category 1 Credit™

  2. Overview • The participant will understand what an endocrine disruptor is. • The participant will be able to list and describe the “dirty dozen” endocrine disruptors that are best avoided. • The participant will be able to list adverse effects the of endocrine disruptors have on animals and man.

  3. What are Endocrine Disruptors? • Endocrine disruptors are substances or mixtures that alter the functions of your endocrine system and consequently cause adverse health effects, either in your body or in your offspring. • So far, the main areas of scientific study have focused on disruption of the hormones that play a major part in development and reproduction, mainly estrogens and androgens. Reference Stein Bibliography: Endocrine Disruptors #1, 2

  4. The Dirty Dozen -- Potential Endocrine Disruptors to Avoid • Endocrine-disrupting chemicals are everywhere these days. You are exposed to them from a variety of sources, including countless common household products, toys, personal care products, and cosmetics. Reference Stein Bibliography: Endocrine Disruptors #3

  5. Phthalates Bisphenol A Perfluorooctanoic acid (PFOA) Methoxychlor and Vinclozin Nonylphenol ethoxylates (NPEs) Bovine growth hormones Soy products MSG Fluoride Synthetically produced pharmaceuticals Natural chemicals Man-made chemicals and by-products The Dirty Dozen -- Potential Endocrine Disruptors to Avoid Reference Stein Bibliography: Endocrine Disruptors #3

  6. Phthalates • Exposure to phthalates can lead to incomplete testicular descent in fetuses. • Found in vinyl flooring, detergents, automotive plastics, soap, shampoo, deodorants, fragrances, hair spray, nail polish, plastic bags, food packaging, garden hoses, inflatable toys, blood-storage bags, and intravenous medical tubing. Reference Stein Bibliography: Endocrine Disruptors #3, 4

  7. Bisphenol A • A common ingredient in many plastics, including reusable water bottles, food can linings and dental sealants. • BPA can change the course of fetal development in a way that increases the risk of breast cancer. • Baby bottles (and other refillable hard plastic bottles and plastic flatware) are commonly made from polycarbonate plastics, the most common type on the market. Reference Stein Bibliography: Endocrine Disruptors #3, 5

  8. Bisphenol A • When washed and heated (say, in the microwave), these plastics give off BPA. BPA is a hormone disruptor that mimics estrogen and has been tied to developmental and neurological problems for unborn children. • In animals, BPA has contributed to reproductive system abnormalities such as infertility, enlarged prostate, and abnormal chromosomes, as well as obesity and insulin resistance, a precursor to diabetes. Reference Stein Bibliography: Endocrine Disruptors #5

  9. Chemical in Food Containers Linked to Heart DiseasePoisons In Your Food Could Be Killing You • A chemical commonly used in coatings inside food and beverage cans and to manufacture clear plastic bottles may be harmful to the heart. • The chemical, bisphenol A (BPA), may cause arrhythmias or irregular heartbeats, especially for women, according to a University of Cincinnati study by Scott Belcher, an associate pharmacology professor at the university. Reference Stein Bibliography: Endocrine Disruptors #6

  10. Chemical in Food Containers Linked to Heart DiseasePoisons In Your Food Could Be Killing You • BPA is found in baby bottles, bottle tops, and dental fillings and sealants. • It has been in use for more than 50 years and is a key component of epoxy resins used to line cans, as well as polycarbonate plastics used to make bottles. Reference Stein Bibliography: Endocrine Disruptors #7, 8

  11. Chemical in Food Containers Linked to Heart DiseasePoisons In Your Food Could Be Killing You • BPA has been tied to diabetes, prostate and breast cancer, and neurological defects, but the study links it to arrhythmias in women. • In the study, BPA demonstrated an estrogen-like effect on the heart, altering the concentration of free calcium in the heart muscle cells of female mouse hearts and causing improperly controlled beating, the researchers said. Reference Stein Bibliography: Endocrine Disruptors #6, 9

  12. Chemical in Food Containers Linked to Heart DiseasePoisons In Your Food Could Be Killing You • “Low doses of BPA markedly increased the frequency of arrhythmic events,” Belcher said. “The effect of BPA on these cardiac arrhythmias was amplified when exposed to estradiol, the major estrogen hormone in humans.” • “Basically, it’s very clear that BPA is acting like estrogen,” Belcher told Forbes. “If we give estrogen at physiological concentrations, then add BPA, it’s actually a synergistic effect. It’s not like adding the two together. It’s worse.” Reference Stein Bibliography: Endocrine Disruptors #6

  13. Chemical in Food Containers Linked to Heart DiseasePoisons In Your Food Could Be Killing You • Women are more prone to die following a heart attack than men, and Belcher theorizes that a higher rate of arrhythmias in women might be at least partially to blame. Research on the theory is in its early stages. Reference Stein Bibliography: Endocrine Disruptors #6

  14. Chemical in Food Containers Linked to Heart DiseasePoisons In Your Food Could Be Killing You • BPA is in such widespread use that the Centers for Disease Control found bisphenol A in the urine of 93 percent of adults and children tested five years ago. In light of such figures and of studies such as the University of Cincinnati research, the FDA recently consented to reevaluate its recommendations of safe levels of BPA in common products. • Representatives of the chemical industry continue to voice their disagreement that BPA is harmful. Reference Stein Bibliography: Endocrine Disruptors #8

  15. Safe Plastic Containers? • Polyethylene is safe, polycarbonate isn't; • Polypropylene is safe, bisphenol A isn't. • After repeated reheating, polycarbonate, a chemical seen in several plastic storage products, can leak BPA, the dangerous hormone disruptor found in some baby bottles. • Polyethylene terephthalate (PET), the chemical in most plastic soda bottles, leaks the hormone-disrupting carcinogens called phthalates after repeated use. • Deli plastic like polyvinyl chloride (PVC) can also release dioxins. Reference Stein Bibliography: Endocrine Disruptors #10

  16. Perfluorooctanoic acid (PFOA) • Found in grease- and water-resistant coatings like Teflon and Gore-Tex, is a likely carcinogen • A March 10, 2009 agreement between the Environmental Protection Agency (EPA) and E.I. du Pont de Nemours and Co. over drinking water contamination around the company’s Parkersburg, WV, plant leaves people in the area exposed to dangerous levels of the Teflon chemical perfluorooctanoic acid (PFOA), a probable carcinogen and reproductive system toxin also known as C8. Reference Stein Bibliography: Endocrine Disruptors #11

  17. Perfluorinated acids (PFA)Perfluorooctanoic acid (PFOA) • Nonstick and stain-resistant coatings, used on everything from your favorite omelette (Teflon) pan to your suede sofa, include perfluorinated acids (PFAs). • Though their toxicity in humans is still unclear(?), in animals, PFAs cause birth defects, thyroid hormone abnormalities, and liver damage. Reference Stein Bibliography: Endocrine Disruptors #10

  18. Methoxychlor and Vinclozin • An insecticide and a fungicide respectively, have been found to cause epigenetic changes to male mice born for as many as four subsequent generations after the initial exposure. Reference Stein Bibliography: Endocrine Disruptors #12

  19. Nonylphenol Ethoxylates (NPEs) • Known to be potent endocrine disruptors, these chemicals affect gene expression by turning on or off certain genes and interfere with the way your glandular system works. • They mimic the female hormone estrogen and have been implicated as one reason behind some marine species switching from male to female. • Some of the products where NPEs are found are cleaners, detergents, and shampoos. Reference Stein Bibliography: Endocrine Disruptors #13

  20. Bovine Growth Hormone • Manufactured by Monsanto and now sold to Lilly Veterinary division • Commonly added to commercial dairy, it has been implicated as a contributor to premature adolescence. Reference Stein Bibliography: Endocrine Disruptors #14, 15

  21. Soy Products • Loaded with hormone-like substances. • Soy is not the healthy food many think it is. • Very widespread in the food chain. Reference Stein Bibliography: Endocrine Disruptors #16 - 18

  22. Chemical in Soybeans Causes Sexual Dysfunction in Male Rats • The male offspring of rats fed diets containing genistein, a chemical found in soybeans, developed abnormal reproductive organs and had sexual dysfunction as adults. • This finding may indicate a need for further research to determine whether exposure to genistein while in the womb and during breastfeeding influences human reproductive development, according to researchers. Reference Stein Bibliography: Endocrine Disruptors #19

  23. Chemical in Soybeans Causes Sexual Dysfunction in Male Rats • The study involved pregnant rats that were fed one of three diets: a genistein-free diet, a diet supplemented with a low dose of genistein, and a diet with a high dose of genistein. • The male offspring were exposed to genistein indirectly through their mothers’ diets during pregnancy and lactation. Reference Stein Bibliography: Endocrine Disruptors #19

  24. Chemical in Soybeans Causes Sexual Dysfunction in Male Rats • Researchers found that while the sperm counts of genistein-exposed males were normal, they had smaller testes and a larger prostate gland than unexposed rats. • They also had lower testosterone levels and were less likely to ejaculate than unexposed rats. • The effects of genistein exposure continued long after the rats were exposed. • Researchers felt that exposure during reproductive development may have negative, long-term consequences in males. Reference Stein Bibliography: Endocrine Disruptors #19

  25. Chemical in Soybeans Causes Sexual Dysfunction in Male Rats • It is thought that genistein may act as an estrogen or an anti-androgen blocking the function of the sex hormones, known as endogenous androgens, necessary for males to develop a normal reproductive system. • Further studies are needed to determine whether exposure to genistein during gestation, lactation, or both caused the long-term effects seen in the study, researchers noted. Reference Stein Bibliography: Endocrine Disruptors #19

  26. Monosodium Glutamate (MSG) • A food additive that is an excitotoxin. • A glutamate stimulator that causes brain damage. • Has been linked to reduced fertility. Reference Stein Bibliography: Endocrine Disruptors #20

  27. See next slide

  28. Glutamate Induced Damage • When the brain suffers an injury such as a stroke, neurons release glutamate onto nearby neurons which become excited, overloaded with calcium and die (left). • Normal neurotransmission (above) is altered during injury, causing excess calcium to activate enzymes which eventually leads to destruction of the cell. • Since this occurs through glutamate receptors, including NMDA receptors, scientists believe that damage can be stopped through the use of agents that block these receptors. Several of these drugs are now in human clinical trials. Reference Stein Bibliography: Endocrine Disruptors #20, 21

  29. Excitotoxins Additives that ALWAYS contain MSG Monosodium GlutamateHydrolyzed Vegetable ProteinHydrolyzed ProteinHydrolyzed Plant ProteinPlant Protein ExtractSodium CaseinateCalcium CaseinateYeast ExtractTextured ProteinAutolyzed YeastHydrolyzed Oat Flour Reference Stein Bibliography: Endocrine Disruptors #20, 21

  30. ExcitotoxinsAdditives that FREQUENTLY contain MSG Malt ExtractMalt FlavoringBouillonBrothStockFlavoringNatural FlavoringNatural Beef or Chicken FlavoringSeasoningSpices Reference Stein Bibliography: Endocrine Disruptors #20, 21

  31. ExcitotoxinsAdditives that MAY contain MSG or Excitotoxins CarrageenanEnzymesSoy Protein ConcentrateSoy Protein IsolateWhey Protein Concentrate • Protease enzymes of various sources can release excitotoxin amino acids from food proteins Reference Stein Bibliography: Endocrine Disruptors #20, 21

  32. Fluoride • This chemical in the U.S. water supply has been linked to lower fertility rates, hormone disruption and low sperm counts. • Does nothing to prevent tooth decay or reverse osteoporosis. Reference Stein Bibliography: Endocrine Disruptors #22

  33. Synthetically Produced Pharmaceuticals • Intended to be highly hormonally active, such as contraceptive pills and treatments for hormone-responsive cancers. • Your body is not designed to be exposed to these synthetic hormones and long-term use will invariably increase your risk of developing serious chronic illness. Reference Stein Bibliography: Endocrine Disruptors #23

  34. Other Natural Chemicals • Includes toxins produced by components of plants (the so-called phytoestrogens, such as genistein or coumestrol) and certain fungi. Reference Stein Bibliography: Endocrine Disruptors #24

  35. Other Man-made Chemicals And By-products Released Into The Environment • These include some pesticides (such as pyrethroids, linuron, vinclozolin, fenitrothion, DDT and other chlorinated compounds), and a number of industrial chemicals like polychlorinated biphenols (PCBs) and dioxins. Reference Stein Bibliography: Endocrine Disruptors #23, 24

  36. How Do These Endocrine Disruptors Affect Your Health? • Declining sperm counts • Increased incidences of male children born with genital malformations • Increased incidences of certain hormone-sensitive types of cancer • Impaired neural development causing memory problems and lower IQ • Impaired sexual behavior • Precocious puberty • Retarded sexual development Reference Stein Bibliography: Endocrine Disruptors #24

  37. Actions of Endocrine Disruptors • These types of chemicals can exert their effects by: • Mimicking the biological activity of your hormones by binding to a cellular receptor. This can initiate your cell's normal response to the naturally occurring hormone at the wrong time or to an excessive extent (agonistic effect). • Binding to the receptor but not activating it. Instead, the presence of the chemical on the receptor prevents binding of the natural hormone (antagonistic effect). Reference Stein Bibliography: Endocrine Disruptors #24

  38. Actions of Endocrine Disruptors • Binding to transport proteins in your blood, thus altering the amounts of natural hormones that are present in your blood circulation. • Interfering with the metabolic processes in your body affecting the synthesis or breakdown rates of your natural hormones. Reference Stein Bibliography: Endocrine Disruptors #24

  39. Take Test • Module 12 Slide Show 3: Endocrine Disruptors