Pesticides chlorpyrifos

Barr, D.B., and J. Angerer. In press. Potential uses of biomonitoring data A case study using the organophosphorus pesticides chlorpyrifos and malathion. Environ Health Perspect. [online]. Available http //ehp.niehs.nih.gov/docs/2006/9062/abstract.html [accessed Aug. 21,2006],... 

Fenske, R.A. and C. Lu (1994). Determination of Handwash Removal Efficiency Incomplete Removal of the Pesticide, Chlorpyrifos, from Skin by Standard Handwash Techniques, Am. Ind. Hyg. Assoc. J., 55, 425-432. 

The toxic effects of some pesticide mixtures are additive, particularly when their toxic mechanisms are identical. The additive effects of the organophosphates chlorpyrifos and diazanon were demonstrated in one study. T Another study found the s-triazine herbicides atrazine and cyanazine to show additive toxic effects. Not all mixtures of similar pesticides produce additive effects, however. In one study, mixtures of five organophos-phate pesticides (chlorpyrifos, diazinon, dimethoate, acephate, and malathion) were shown to produce greater than additive effects when administered to laboratory animals. Another article discusses nonsimple additive effects of pyrethroid mixtures. Despite the similarities in their chemical structure, pyrethroids act on multiple sites, and mixtures of these produce different toxic effects. 10 ... 

Metals (lead), PAHs (phenanthrene), and pesticides (chlorpyrifos)... 

Sultatas, L. G. (1988). Factors affecting the hcpaiLc biotrans-fonrtation of the phosphorothioatc pesticide chlorpyrifos. Toxicology 51, 191-200. 

A recent study of Moser eoworkers (2005) Mo,ser et uL (2005), using a do.se-additive design with mixtures of five commonly used OP pesticides (chlorpyrifos, diazinon, dimeihoate, acephaic, and malathion), showed a more-than-additive interaction on multiple end points blood and brain cholinesterase inhibition, motor activity, and gait score (tail-pinch response did not. show a more-than-additive interaction). This study is noteworthy because (i) relatively sensitive end points were used to test the toxic interaction of the OP pesticides, such as cholinesterase inhibition or depression of motor activity (ii) more than two OP compounds were used in the mixture and (iii) comprehensive statistical analyses of the data were performed. The pharmacokinetic interaction of two of the aimpounds in the mixture, chlorpyrifos and diazinon, has been studied in rats (Timchalk et a ., 2004). The authors found that one compound did not affect the pharmacokinetics of the other unless high doses were given, concluding that a more-than-additive interaction is unlikely at environmentally relevant concentrations. 

ATSDR publi.shes toxicological profiles for hazardous substances. The toxicological profiles for the pesticides chlorpyrifos, chlorfenvinphos, diazinon, dichlorvos, disul-folon, ethion, malathion, and methyl parathion have been published. Each of these profiles contain.s a section on analytical methods for the pesticide and its metabolites. The references for various analytical methods are given. 

Organophosphate pesticides chlorpyrifos, ethylparathion, fenthion, methylpaiathion... 

A well-documented example of this approach is a study of the fate of the pesticide, chlorpyrifos, in a pond in Missouri (87 reviewed by Branson, 75). The conceptual model includes rate constants for each of the transport and transformation processes affecting the final concentrations of chlorpyrifos in the water, the sediment, and the fish. The rate constant for evaporation from water is estimated from data on vapor pressure, solubility, and molecular weight (for techniques, see 33, 68, 71). The remaining rate constants for the pond model are derived from laboratory studies. When validated by sampling in a pond, the predicted and environmentally measured concentrations of chlorpyrifos showed close agreement (75). 

The following are examples of TLC analyses in which SFE was the method used for sample preparation lipids in wool (analysis by TLC-FID) hpids in fish feed (TLC-FID) the pesticide chlorpyrifos and its degradation products in soil hydrocarbons in heavy petroleum products (TLC-FID) aromatic and ahphatic hydroperoxides in solid matrices (online sample transfer to TLC plates) colored fractions from a Mediterranean brown alga essential oil in foods " and cyanazine from soil (silica gel TLC-densitometry at 220 nm). " ... 

An important substrate for P450 2B6 is the antimalarial dmg artemisinin [573]. Another is methadone, used in treating heroin addiction [574]. P450 2B6 is also involved in the metabo-hsm of a number of environmental chemicals, including the pesticide chlorpyrifos [575]. 

Hexaflumuron has very low toxicity to mammals so its manufacturing facility would offer little interest to terrorists seeking explosive or hazardous targets. It is a replacement for the neurotoxic pesticide chlorpyrifos a broad-spectrum chlorinated organophosphate... 

Foxenberg RJ, Ellison CA, Knaak JB, Ma C, Olson JR (2011) Cytochrome P450-specific human PBPK/PD models for the organophosphorus pesticides chlorpyrifos and parathion. Toxicology 285 57-66... 

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