Responses and recovery pattern of sex steroid hormones in testis of Nile tilapia (Oreochromis niloticus) exposed to sublethal concentration of methomyl.
Tilapia were exposed to sublethal methomyl concentrations of 0, 0.2, 2, 20 or 200 μg/L for 30 days, and then transferred to methomyl-free water for 18 days. The sexual steroid hormones 17β-estradiol (E2), testosterone (T), and 11-ketotestosterone (11-KT) in tilapia testes were examined at 0, 6, 12, 18, 24 and 30 days after methomyl exposure, and at 18 days after fish were transferred to methomyl-free water. There were no significant changes in the hormone parameters in testes of tilapia exposed to low concentration 0.2 and 2 μg/L methomyl compared with the controls. However, high concentration 20 and 200 μg/L methomyl had the potential to disrupt the endocrine system of male tilapia, as shown by an increase in E2 and a decrease in T and 11-KT in the testes. Thus, it would appear that the 2 μg/L methomyl might be considered the no-observed-adverse-effect level. Recovery data showed that the effects produced by the lower concentration of 20 μg/L were reversible but the effects were not reversible at the higher concentration of 200 μg/L.
['Meng|Shun Long|SL|', 'Qiu|Li Ping|LP|', 'Hu|Geng Dong|GD|', 'Fan|Li Min|LM|', 'Song|Chao|C|', 'Zheng|Yao|Y|', 'Wu|Wei|W|', 'Qu|Jian Hong|JH|', 'Li|Dan Dan|DD|', 'Chen|Jia Zhang|JZ|', 'Xu|Pao|P|']
D000818:Animals D023681:Cichlids D004958:Estradiol D005260:Female D012739:Gonadal Steroid Hormones D008297:Male D008724:Methomyl D019055:No-Observed-Adverse-Effect Level D013737:Testis D013739:Testosterone D059551:Toxicity Tests, Subacute D014874:Water Pollutants, Chemical
Recovery pattern Sex steroid hormone Testis Tilapia Methomyl