Endocrine Disruption Josh Monroe WFS 433 4/9/15

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1 Endcrine Disruptin Jsh Mnre WFS 433 4/9/15 Outline What is Endcrine Disruptin? Hw des it wrk? Examples f Endcrine Disruptrs Bisphenl A DDT Atrazine Implicatins fr Survival Why Endcrine Disruptin is the MAIN reasn fr declines Final Remark What is Endcrine Disruptin? Endcrine disruptrs are chemicals that, at certain dses, can interfere with the endcrine (r hrmne) system These disruptins can cause cancerus tumrs, birth defects, and ther develpmental disrders 1

2 4/9/15 Hw des it wrk? When absrbed in the bdy, an endcrine disruptr can: decrease r increase nrmal hrmne levels (left) mimic the bdy's natural hrmnes (middle) alter the natural prductin f hrmnes (right). Surce: endcrine/ Examples f Disruptrs Bisphenl A DDT Atrazine Can act as a thyrid hrmne antagnist Can act as an estrgen mimic Can act as a crticsterid mimic Can induce gnadal abnrmalities Can induce hermaphrditism Cncentratin Species Effect 2.28 µg Western Clawed Frg Inhibitin f spntaneus metamrphsis 22.8 µg African Clawed Frg (Larvae) Cmplete sex reversal 200 µg Japanese Pnd Frg Tadple tail malfrmatins 4600 µg African Clawed Frg (Embyr) Abnrmal gut ciling, edema, micrcephaly, decrease in bdy length 2

3 Effects f DDT Atrazine millin punds f active ingredient sld every year since 2001 Currently the #2 mst cmmn herbicide used in the United States #1 is glyphsate Surce: EPA s Pesticide Industry Sales and Usage Market Estimates 2007 EPA reprted that $2 billin/year in sales f crp wuld be lst if farmers did nt have access t Atrazine fr cntrlling grasses Surce: In 2007, EPA reprted that Atrazine des nt negatively impact amphibian gnadal develpment Federal Insecticide, Fungicide, and Rdenticide Act (FIFRA) Scientific Advisry Panel (SAP) hsted in June

4 Surce: Hayes et al., 2003 Effects f Atrazine 25 ppb Atrazine nce every three days 10 fld decrease in nrmal levels We hypthesize that atrazine induces armatase and prmtes the cnversin f teststerne t estrgen. This disruptin in steridgenesis likely explains the demasculinizatin f the male larynx and the prductin f hermaphrdites. Males are reprductively dead IF sperm can be generated, 10% fertility Genetically male female frgs prduce nly male ffspring Wipe ut ppulatins due t skewed sex ratis Surce: Hayes et al., 2002 Implicatins fr Survival Inhibitin f spntaneus metamrphsis Reduced ability t escape predatin Decreased teststerne Reduced ability t reprduce Cmplete sex reversal Reduced ability t prpagate Tadple tail malfrmatins Reduced mbility Cmpetitin and predatin implicatins Abnrmal gut ciling Reduced ability t digest fd Edema Mbility and develpment implicatins Micrcephaly Reduced life span Reduced cgnitive ability Develpmental inhibitin Reduced ability t feed, breathe Cmpetitin and predatin implicatins (gape) 4

5 Endcrine Disruptrs: The MAIN Reasn fr Amphibian Declines! The human ppulatin is grwing expnentially Greater demand fr plastics, fd (herbicides and pesticides) All f these chemicals are artificial and assciated with water pllutin Peak runff rates ccur during spring Peak amphibian activity ccurs during the same perid Atrazine is the mst cmmn cntaminant f grund and surface water 0.5 millin punds per year are depsited in precipitatin in the US Cntaminatin can spread mre than 600 miles frm the pint f applicatin Perhaps emergent diseases (ranavirus, chytrid) are nt emergent at all Maybe what is emergent is the inability t munt prper immune respnses as a result f pesticide expsure (Hayes et al., 2006) Final Remark Unfrtunately, almst all research n amphibian ppulatin declines has fcused n single factrs r multiple factrs cnsidered individually with little cnsideratin fr interactins (Sparling et al., 2003) References Flint, Shelby, et al. "Bisphenl A expsure, effects, and plicy: a wildlife perspective." Jurnal f envirnmental management 104 (2012): Hayes, Tyrne B., Tzu Ha Wu, and Tanya N. Gill. "DDT-like effects as a result f crticsterne treatment in an anuran amphibian: Is DDT a crticid mimic r a stressr?." Envirnmental txiclgy and chemistry 16.9 (1997): Hayes, Tyrne B., et al. "Hermaphrditic, demasculinized frgs after expsure t the herbicide atrazine at lw eclgically relevant dses." Prceedings f the Natinal Academy f Sciences 99.8 (2002): Hayes, Tyrne, et al. "Atrazine-induced hermaphrditism at 0.1 ppb in American lepard frgs (Rana pipiens): labratry and field evidence." Envirnmental Health Perspectives (2003): 568. Hayes, Tyrne B., et al. "Pesticide mixtures, endcrine disruptin, and amphibian declines: are we underestimating the impact?." Envirnmental Health Perspectives 114 (2006): 40. Sparling DW, Krest SK, Linder G Multiple stressrs and declining amphibian ppulatins: An integrated analysis f cause-effect t supprt adaptive resurce management. In: Amphibian Decline: An Integrated Analysis f Multiple Stressr Effects. Linder G, Krest SK, Sparling DW. (eds.) SETAC Press. Pensacla, FL. 5