6533b7defe1ef96bd1275d7b

RESEARCH PRODUCT

Detection of a synthetic sex steroid in the American crocodile (Crocodylus acutus): Evidence for a novel environmental androgen

Davinia B. GarrigósChristopher M. MurraySergio PadillaCraig GuyerMichael EasterMahmood Sasa MarínMahmood Sasa MarínMark Merchant

subject

Male0106 biological sciences0301 basic medicineHealth Toxicology and MutagenesisEndocrine DisruptorsCrocodile01 natural sciencesMethyltestosteroneGonadal Steroid HormonesAlligators and Crocodileseducation.field_of_studybiologyGeneral MedicinePollutionEnvironmental androgenAndrogensFemaleSteroidsEnvironmental MonitoringCosta Ricamedicine.medical_specialtyEnvironmental Engineeringfood.ingredient597.987 286 Crocodilia (Cocodrilos)medicine.drug_classPopulationCrocodylus acutusZoology010603 evolutionary biologyCrocodylus03 medical and health sciencesfoodRiversbiology.animalYolkInternal medicinemedicineAnimalsEnvironmental ChemistryeducationSexual differentiationPublic Health Environmental and Occupational HealthEstrogensGeneral ChemistryAndrogenbiology.organism_classificationUnited StatesCrocodylus030104 developmental biologyEndocrinologySex steroidWater Pollutants ChemicalEndocrine disrupting contaminants

description

Endocrine-disrupting contaminants (EDC's) are well known to alter sexual differentiation among vertebrates via estrogenic effects during development, particularly in organisms characterized by temperature-dependent sex determination. However, substances producing androgenic effects typically lack potency when tested in laboratory settings and are virtually unstudied in field settings. Here, we assay levels of a synthetic androgen, 17a-methyltestosterone (MT), in a heavily male-biased population of American crocodiles in the Tempisque River Basin of Costa Rica based on the recent hypothesis that this chemical is an EDC in developing crocodilian embryos. The presence of MT was documented in all fieldcollected samples of egg yolk and in plasma of all age classes in among population of crocodiles. Hatchlings exhibited higher plasma MT concentrations (102.1 ± 82.8 ng/mL) than juveniles (33.8 ± 51.5) and adults (25.9 ± 20.8 ng/mL). Among populations, crocodiles captured in the Tempisque River (62.9 ± 73.7 ng/mL) were higher in MT concentration than those from Tarcoles (13.3 ± 11.4 ng/mL) and negative controls (0.001 ± 0.0002 ng/mL). A mechanism for the bio-transport of MT and its subsequent effects is proposed. Universidad de Costa Rica/[741-B5-270]/UCR/Costa Rica Organization for Tropical Studies/[OTS 507]/OTS/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP) UCR::Vicerrectoría de Docencia::Salud::Facultad de Microbiología

yearjournalcountryeditionlanguage
2017-08-01Chemosphere
https://doi.org/10.1016/j.chemosphere.2017.04.020