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1 The Environment and Reproductive Health: Why What We Eat, Breath and Touch Matters Susan Davidson, MD Dean Medical Center I have no financial disclosures 1

2 Many Complex Factors Interact to Affect the Impact of Exposures Reproductive health & fetal/child development Adapted from Hubbs-Tait et al. Psychological Science in the Public Interest Scope of the Chemicals Problem Hazard Data - Chemicals Produced > 1 Million Pounds/Year 7% Full* Set of Basic Toxicity Tests: * Doesn t Include Tests of Neurodevelopmental Effects 2

3 Routes of Exposure Inhalation Ingestion Skin contact In utero exposure (fetus) Critical Periods for Environmental Sensitivity in Human Development Fetal/Neonatal Life Childhood Puberty Pregnancy more Klaassen C. In: Casarett & Doull s Toxicology: The Basic Science of Poisons. 7 th ed Many of the effects of exposure are neurodevelopmental 3

4 Some General Principles Safe Blood Lead Levels have Dropped Over Time Latency between exposure and effect Windows of vulnerability in human development With increased scientific understanding toxic thresholds tend to fall Safe thresholds for biological effects are difficult to determine as effects are not linear Mechanisms of Reproductive Health Disruption Endocrine disruption Teratogenicity: Disruption of the development of a fetus or embryo Mutogenicity: The ability to change genetic material Toxicity: The ability of a substance to harm an organism ENDOCRINE DISRUPTORS Naturally occurring or synthetic chemical that affects an organism by as acting as a hormone agonist or antagonist Effects can be transmitted to future generations by epigenetic modifications. Commonly effect thyroid and steroidal hormones such as estrogen and testosterone PLASTICIZERS BPA PHTHALATES 24 4

5 What is BPA? Bisphenol A (BPA)is a chemical (synthetic estrogen) used in hard plastic bottles and the epoxy resin lining of food and beverage cans, thermal receipts Linked with many health effects from breast cancer, prostate cancer to obesity Often being replaced by BPS thermal receipts 5

6 BPA and PCOS Serum BPA levels measured in 71 women with PCOS and 100 controls Serum BPA significantly increased in both lean and obese PCOS patients Environmental Effects of Female Fertility Increased BPA levels associated with Increased odds of implantation failure Increased miscarriage Reduced fertility Serum BPA associated with testoterone and androstenedione levels Serum BPA correlated with insulin levels Holding a thermal receipt after using Purell hand sanitizer Phthalates Noncovalently bound esters used to add flexibility and longevity to plastics Found in a wide variety of products including adhesives, glues, electronics, building materials, personal care products, children s toys, pharmaceuticals, food products, textiles. Most exposure through ingestion also inhalation and skin Occupational exposures 6

7 Phthalates-Why & Where Makes plastics softer/makes fragrances last longer Nail polish Baby toys (now banned in toys for children under 12) Shower curtains Garden hoses Plastic containers Medical tubing Perfumes Personal care products-moisturizers, makeup, shampoo, deodorant, shaving cream, baby washes Phthalates also found in food High levels Poultry Margarine cooking oils, butter, lard Cream, ice cream, cheese Phthalate Exposure and Pregnancy Prenatal phthalate exposure impairs testicular function and shortens anogenital distance in rats. Anogenital distance correlates with penile volume and incomplete testicular descent Human study confirmed decreasing anogenital distance with increased urinary metabolites of phthalates during pregnancy Swan et al. Decrease in Anogenital Distance among Male infants with Prenatal Phthalate Exposure. Environmental Health Perspectives, August, 2005 Phthalates also linked to: Behavioral disorders AutisimSpectrum disorder Neuorodevelopmen tal disorders Altered reproductive function Asthma ADHD Breast Cancer Obesity 7