Effects of polybrominated diphenyl ethers on steroidogenesis in rat leydig cells

In the  Fourth National Report on Human Exposure to Environmental Chemicals (Fourth Report) , CDC scientists measured ten different PBDEs in the blood serum (the clear portion of blood) of at least 1,985 participants aged 12 years and older who took part in the National Health and Nutrition Examination Survey (NHANES) during 2003–2004. In addition, BB-153, which is one of the PBBs, was measured in 2,032 participants aged 12 years and older. By measuring PBDEs and PBBs in blood serum scientists can estimate the amounts of these chemicals that have entered people’s bodies.

In the  Fourth National Report on Human Exposure to Environmental Chemicals (Fourth Report) , CDC scientists measured 13 phthalate metabolites in the urine of 2,636 or more participants aged six years and older who took part in the National Health and Nutrition Examination Survey (NHANES) during 2003–2004. For several phthalate metabolites, results from the prior survey periods of 1999–2000 and 2001–2002 are also included in the  Fourth Report . By measuring phthalate metabolites in urine, scientists can estimate the amount of phthalates that have entered people’s bodies.

A new toxic menace, polybrominated diphenyl ethers (PBDEs), is being detected in the aquatic environment all over the world. The environmental presence of PBDEs and its entry into the environment as BDE-47 and -99 make quality aquatic toxicity data necessary to assess the aquatic hazard risk of PBDs. This study examines the effects of three PBDE-47 and -99 on embryo and larval stages of the marine flatfish turbot ( Psetta maxima ). The acute toxicity of the three PBDEs was examined and NOEC, LOEC, LC10 and LC50 were calculated. All tested compounds caused lethal as well as nonlethal malformations during embryo development. The effects of PBDEs in the different life stages of turbot were analysed. PBDEs seemed to be teratogenic at concentrations higher than and µgL-1 for BDE-47 and -99 respectively, leading to prolonged delays in embryo development and consequent death (at 48 h), as well as severe malformations and mortality of larvae. PBDEs showed a higher acute toxicity for embryo-larvae (LC50 for lethal endpoints to embryos µg BDE-47 L-1 and µg BDE-99 L-1, and and µg L-1 for BDE-47 and -99, respectively for larvae). Generally, the BDE-47 seemed to cause adverse effects at comparatively low dose rates, whereas much higher doses were needed to cause the same effects with BDE-99. The results of the present study show that the acute toxicity of PBDEs decreases as the degree of bromination increases, since the order of toxicity was BDE-47˃ BDE-99. The major isomers also exhibited a clear toxic potential for turbot ELS although at high concentrations, above solubility saturation, pointing at particulate matter as the main via of uptake for those hydrophobic molecules.

Effects of polybrominated diphenyl ethers on steroidogenesis in rat leydig cells

effects of polybrominated diphenyl ethers on steroidogenesis in rat leydig cells

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