Atrazine thyroid

After these initial steps, TIQDT was tested for its capacity to screen environmentally relevant compounds. 2,4-Dichlorophenoxyacetic acid (2,4-D), l,l-bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT), and 4-nonylphenol (4-NP) were selected as they are usually considered to be TGFDs [52-55]. Reports concerning the effect of methyhnercury (MeHg) on thyroid function are contradictory [56-58]. Two environmentally relevant compounds with no reported effects on the thyroid system, fenoxicarb and atrazine [59, 60], were included as negative controls to assess the specificity of the assay. Our data strongly suggest that TIQDT may be... 

Stoker TE, Guidici DL, Cooper RL (2002) The effects of atrazine metabolites on puberty and thyroid function in male Wistar rat. Toxicol Sci 67 198-206... 

Laws, S.C., J.M. Ferrell, T.E. Stoker, J. Schmid, and R.L. Cooper (2000). The effects of atrazine on female Wistar rats An evaluation of the protocol for assessing pubertal development and thyroid function. Toxicol. Sci., 58 366-376. 

Changes in plasma corticosterone and thyroxine concentrations were reported in salamander larvae Ambystoma tigrinum) exposed to atrazine at concentrations of 75 and 250 g/L (29). The authors did not suggest that this was an atrazine-specific mechanism but rather that it was a conq>ensatory response to stress from an environmental contaminant. In addition, since die development of the laryngeal dilator muscle is dependent on both androgen and thyroid hormone, the fact that effects were not observed in male X, laevis in all but one of the studies conducted with atrazine supports the conclusion that atrazine did not disrupt thyroid hormone status in these frogs (17,19,27), Overall, there is no evidence that atrazine affects thyroid-mediated processes in amphibians. 

---