RESUMO
Exposure to tin in the general US population is near ubiquitous, as determined using urinary tin levels measured by inductively coupled plasma mass spectrometry (ICP-MS). Urinary tin levels are associated with chronic health outcomes, such as diabetes; however, it is unclear if these associations are due to the presence of inorganic and organic forms of tin in urine. To address this knowledge gap, levels of total tin and several organotin compounds (OTCs) were measured in convenience urine samples from pregnant women and adults from Iowa, United States. Total tin and OTC levels in urine samples were quantified using ICP-MS and gas chromatography with pulsed flame photometric detection (GC-PFPD), respectively. ICP-MS detected tin in almost all urine samples from both study populations. Low levels of dibutyltin were detected in two out of fifty human urine samples. Importantly, storage of urine samples in plastic containers, but not HNO3-pretreated glass vials drastically reduced the recoveries of OTCs, in particular, tributyltin. Although their detection frequency is low, exposures to OTC should be considered when studying associations between human exposures to tin compounds and adverse health outcomes; however, urinary OTC levels measured in banked urine samples may not be suitable as biomarkers of OTC exposure.
Assuntos
Compostos Orgânicos de Estanho/urina , Estanho/urina , Adulto , Feminino , Humanos , Iowa , Masculino , Gravidez , Manejo de Espécimes , Estados UnidosRESUMO
Tetrabutyltin is a stable organotin and may exhibit endocrine disrupting properties. Herein, we investigated effects of tetrabutyltin on the development of rat fetal Leydig cells, which support differentiation of the male reproductive tract in late gestation. Female pregnant Sprague Dawley rats were gavaged with tetrabutyltin (0, 100, 200, and 500â¯mg/kg) from gestational day (GD) 12 to GD 21. Tetrabutyltin dose-dependently decreased testicular testosterone levels (0.756⯱â¯0.208 and 0.813⯱â¯0.277â¯ng/testis at the 200 and 500â¯mg/kg doses, respectively) compared to control (1.692⯱â¯0.218â¯ng/testis) at GD 21. Furthermore, tetrabutyltin induced fetal Leydig cell aggregation, decreased fetal Leydig cell size and cytoplasmic size at the ≥100â¯mg/kg doses, and downregulated the expression levels of Scarb1, Cyp17a1, and Insl3 at doses ≥100â¯mg/kg and Star expression at 200â¯mg/kg. Taking together, the present results indicated that prenatal exposure of male rats to tetrabutyltin affected fetal Leydig cell development.