maneb and cypermethrin

We developed phospho-ERK1/2 ELISA for human and rainbow trout liver cells, employing HepG2 and RTL-W1 cell lines as models. The assay was applied to detect changes in ERK1/2 activity for nine chemicals, added over a wide concentration range and time points. Cell viability was measured to separate ERK1/2 regulation from cytotoxicity. Perfluorooctane sulfonate and carbendazim did not change ERK1/2 activity; influence on ERK1/2 due to cytotoxicity was indicated for tributyltin and cypermethrin. Mancozeb, benzo[a]pyrene, and bisphenol A stimulated ERK1/2 up to ∼2- (HepG2) and 1.5 (RTL-W1)-fold, though the kinetics differed between chemicals and cell lines. Bisphenol A and benzo[a]pyrene were the most potent concentration-wise, altering ERK1/2 activity in pM (HepG2) to nM (RTL-W1) range. While atrazine and ibuprofen increased ERK1/2 activity by ∼2-fold in HepG2, they did not initiate an appreciable response in RTL-W1. This assay proved to be a sensitive, medium- to high-throughput tool for detecting unrecognized ERK1/2-disrupting chemicals.

Topics: Alkanesulfonic Acids; Animals; Atrazine; Benzhydryl Compounds; Benzimidazoles; Benzo(a)pyrene; Carbamates; Cell Line; Cell Survival; Fluorocarbons; Humans; Ibuprofen; Liver; Maneb; MAP Kinase Signaling System; Oncorhynchus mykiss; Phenols; Phosphorylation; Pyrethrins; Trialkyltin Compounds; Water Pollutants, Chemical; Zineb

The complex immune system displays a coordinated transcriptional response to xenobiotic exposure by altering expression of designated transcription factors that, in turn, trigger immune responses. Despite the identification of several transcription factors that contribute to regulatory response, very little is known about the specific role of factors that are triggered due to exposure to obnoxious pesticides. Here, for the first time, alterations in human peripheral blood lymphocyte expression of transcriptional factors - thrombospondin-1 (THBS-1), secretory phospho-protein-1 (SPP-1), glycoprotein non-metastatic-β (GPNMB) and fasciculation and elongation factor ζ-1 (FEZ-1), due to in vitro exposure to the crop protection chemicals cypermethrin and mancozeb are reported. Results revealed significant changes in expression profiles due to mancozeb exposure, supporting its immune dysfunction potential; in contrast, cypermethrin exposure did not cause significant changes. Based on these effects on gene expression across the doses tested, it was likely key components of immune mechanisms such as proliferation, cell adhesion, apoptosis and cell activation in human PBMC were affected. Although these data are from in vitro experiments, the results point out the potential role for changes in these factors in the etiology of defective T-cell immune function seen in humans occupationally exposed to crop protection chemicals like mancozeb. These studies suggest the involvement of transcription factors in regulation of pesticide-induced immune dysfunction; these studies also represent a novel approach for identifying potential immune-related dysfunctions due to exposure to pesticides. Further studies are needed to better understand the functional significance of these in vitro findings.

Topics: Adaptor Proteins, Signal Transducing; Cells, Cultured; Gene Expression Profiling; Gene Expression Regulation; Humans; Leukocytes, Mononuclear; Maneb; Membrane Glycoproteins; Nerve Tissue Proteins; Osteopontin; Pesticides; Pyrethrins; T-Lymphocytes; Thrombospondin 1; Thrombospondins; Transcriptional Activation; Zineb

Effects of water volume and water column height on toxicity of cypermethrin, carbaryl, dichlorvos, tetradifon, maneb, captan, carbosulfan endosulfan and HgCl₂ to juvenile rainbow trout (Oncorhynchus mykiss, 3.2 ± 0.7 g) were evaluated in different glass aquaria under static conditions. When fish were exposed to the chemical compounds in 23 cm water column height (25 L), their mortality ranged between 0% and 58%. At the same water volume, but lower water column height (9 cm), mortality of fish increased significantly and was in a range from 60% to 95%. At the same water column height, toxic effects of chemicals were significantly higher in 25 L water volume than that of 8.5 L, water except maneb which has lowest (-0.45) octanol-water partition coefficient value. Mortality rates ratio of 9 and 23 cm water column height ranged between 1.12 and 90 while mortality rates ratio of 9 and 25 L water volume ranged between 1.20 and 4.0. Because actual exposure concentrations were not affected by either water volume or water column height, we propose that increased pesticides' toxicity was related to an increase in bioassay volume, since more pesticide molecules were able to interact with or accumulate the fish. However, there seem to be no relationship between the effects of water volume, water column height and Kow value of chemicals with regard to toxicity in juvenile rainbow trout.

Topics: Animals; Captan; Carbamates; Carbaryl; Dichlorvos; Dose-Response Relationship, Drug; Endosulfan; Fresh Water; Hydrocarbons, Chlorinated; Maneb; Octanols; Oncorhynchus mykiss; Pesticides; Pyrethrins; Toxicity Tests; Water Pollutants, Chemical