N., and Bakry, N. M. (2006)

Chalfant, R. B., Hall, M. R., Johnson, A. W., Seal, D. R., and BONDARI, K. (1992). Effects of Application Methods, Timing, and Rates of Insecticides and Nematicides on Yield and Control of Wireworms (Coleoptera: Elateridae) and Nematodes (Tylenchida: Heteroderidae) that Affect Sweet Potato. J.Econ.Entomol. 85: 878-887.

EcoReference No.: 85644

Chemical of Concern: DZ,PRN,FNF,EP,CPY; Habitat: T; Effect Codes: MOR; Rejection Code: NO ENDPOINT,CONTROL(DZ).

Chambers, Howard W. and Casida, John E. (1969). Protective activity of 1,3-disubstituted 2- and 6-pyridones against selected neurotoxic agents. Toxicology and Applied Pharmacology 14: 249-258.

Chem Codes: Chemical of Concern: DZ Rejection Code: MIXTURE.

Pretreatment of mice with certain substituted pyridones substantially delays the effects of tri-n-butyl phosphate, tubocurarine, decamethonium, hexamethonium, and EPN. The most effective compounds, in all cases, are esters of 1-methyl-2-oxo-1,2-dihydro-3-pyridinol. With this pyridinol, the methylcarbamate and dimethylcarbamate esters are most effective while the ethyl- and diethylcarbamates are only slightly effective. The diethyl phosphate shows a similar spectrum of activity, but it potentiates rather than alleviates the effects of EPN. Protective effects against poisoning by tubocurarine, hexamethonium, and EPN may result from transient acetylcholinesterase inhibition by the carbamates and of the first two from more prolonged inhibition by the phosphate. Alleviation of the actions of decamethonium by pyridones, however, may result from a different mode of action, the mechanism being unknown. 1-Methyl-2-oxo-1,2-dihydro-3-pyridyl 1-methyl-6-oxo-1,6-dihydronicotinate is effective only against tubocurarine and decamethonium, suggesting specificity for the neuromuscular junction. Tropyl 1-methyl-6-oxo-1,6-dihydronicotinate methiodide acts in the same manner as atropine; it is comparable to atropine sulfate as an antidote for EPN poisoning but is more toxic than atropine sulfate. Though most of the data support the hypothesis that tri-n-butyl phosphate acts primarily as a curarimimetic agent, assays with 3-isopropylphenyl methylcarbamate suggest that this is not necessarily so. Compounds based on 1-methyl-3-substituted 2- or 6-pyridones have certain structural features in common with the configuration of acetylcholine and may be useful in further studies on the functioning of various aspects of the cholinergic system.

Chambers, J. E. and Dorough, G. D. (1994). Toxicologic Problems Associated with Pesticide Mixtures and Pesticide Impurities. In: R.S.H.Yang (Ed.), Toxicology of Chemical Mixtures: Case Studies, Mechanisms, and Novel Approaches, Acad.Press, San Diego, CA 135-155.
Chem Codes: EcoReference No.: 72239
Chemical of Concern: DDT,DZ,PCP,MLN,DXN Rejection Code: MIXTURE/REVIEW.

CHAMBERS JE, CHEN WL, DETTBARN, W., EHRICH, M., ELDEFRAWI AT, GAYLOR DW, HAMERNIK, K., HODGSON, E., KARCZMAR AG, PADILLA, S., POPE CN, RICHARDSON RJ, SAUNDERS DR, SHEETS LP, SULTATOS LG, and WALLACE KB (1998). Common mechanism of toxicity: A case study of organophosphorus pesticides. AU - MILESON BE. TOXICOLOGICAL SCIENCES; 41 8-20.

Chem Codes: Chemical of Concern: DZ Rejection Code: NO TOX DATA.

BIOSIS COPYRIGHT: BIOL ABS. The Food Quality Protection Act of 1996 (FQPA) requires the EPA to consider, "available information concerning the cumulative effects of such residues and other substances that have a common mechanism of toxicity ... in establishing, modifying, leaving in effect, or revoking a tolerance for a pesticide chemical residue." This directive raises a number of scientific questions to be answered before the FQPA can be implemented. Among these questions is: What constitutes a common mechanism of toxicity? The ILSI Risk Science Institute (RSI) convened a group of experts to examine this and other scientific questions using the organophosphorus (OP) pesticides as the case study. OP pesticides share some characteristics attributed to compounds that act by a common mechanism, but produce a variety of clinical signs of toxicity not identical for all OP pesticides. The Working Group generated a testable hypothesis, anticholinesterase OP pesticides act by a common mechanism of toxici Biochemistry/ Poisoning/ Animals, Laboratory/ Herbicides/ Pest Control/ Pesticides/ Arachnida/ Entomology/Economics/ Pest Control, Biological/ Animals

Chapman, P. A. (1985). The Resistance to Eighteen Toxicants of a Strain of Musca domestica L. Collected from a Farm in England. Pestic.Sci. 16: 271-276.

EcoReference No.: 70785

Chemical of Concern: RSM,DDT,HCCH,DZ,MOM,DMT,PPB,DM,BRSM,PYN,FNT,TVP,PIRM,TCF,BDC,PPB,PMR,DDVP,PRM; Habitat: T; Effect Codes: MOR; Rejection Code: NO CONTROL(DM,PMR,DDVP,FNT,MOM,TVP,PIRM,TCF,BDC,DDT,HCCH,TARGET-DZ,DMT),NO MIXTURE(BRSM,RSM,PYNN,PPB).

Chapman, P. A. (1985). The resistance to eighteen toxicants of a strain of Musca domestica L. collected from a farm in England. Pesticide Science [PESTIC. SCI.]. Vol. 16, no. 3, pp. 271-276. 1985.

Chem Codes: Chemical of Concern: DZ Rejection Code: SURVEY.

ISSN: 0031-613X

Descriptors: pesticide resistance
Descriptors: Musca domestica
Descriptors: Muscidae
Descriptors: British Isles, England
Abstract: A sample of houseflies initially collected from a pig farm and found to be resistant to bendiocarb, DDT, gamma-HCH, pyrethrin + piperonyl butoxide (PB), tetrachlorvinphos and trichlorfon, was tested for resistance to knockdown by other toxicants. At the KD sub(50) response level, resistance factors were obtained for: permethrin (x141), deltamethrin (x96), bioresmethrin + PB (x37), resmethrin +33), fenitrothion (x94), bromophos (x58), iodofenphos (x42), pirimiphos-methyl (x30), dichlorvos (x22), dimethoate (x9), diazinon (x8), methomyl (x4) and methomyl + PB (x4). The houseflies on the farm could not be controlled using space sprays of pyrethrins + PB, although resistance to this toxicant was only x12. However, control was achieved with a methomyl bait.
Language: English
English
Publication Type: Journal Article
Classification: Z 05183 Toxicology & resistance
Subfile: Entomology Abstracts

Chapman, Sharon K. and Leibman, Kenneth C. (1971). The effects of chlordane, DDT, and 3-methylcholanthrene upon the metabolism and toxicity of diethyl-4-nitrophenyl phosphorothionate (Parathion). Toxicology and Applied Pharmacology 18: 977-987.

Chem Codes: Chemical of Concern: DZ Rejection Code: NO COC.

In rats, (1) DDT and chlordane cause equal stimulation of both pathways of parathion metabolism, similar to phenobarbital, and (2) 3-methylcholanthrene treatment results in preferential enhancement of the pathway leading to the formation of paraoxon. With mice, (1) DDT treatment results in greater enhancement of the pathway responsible for diethyl hydrogen phosphorothionate than of that producing paraoxon, (2) chlordane equally enhances both pathways of parathion metabolism, and (3) 3-methylcholanthrene treatment results in a repression of diethyl hydrogen phosphorothionate production. The differential inductive effects are discussed in terms of the hypothesis that two separate enzyme systems are involved in the metabolism of parathion. Results from toxicity studies in mice indicate that (1) no significant change in parathion toxicity results from DDT treatment, (2) toxicity is not altered significantly after treatment with 3-methylcholanthrene, and (3) chlordane treatment affords protection against the toxicity of parathion. The lack of correlation between the toxicity studies and the metabolic studies suggests that factors other than metabolism contribute to toxicity.

CHARIZOPOULOS, E. and PAPADOPOULOU-MOURKIDOU, E. (1999). Occurrence of pesticides in rain of the Axios River Basin, Greece. ENVIRONMENTAL SCIENCE & TECHNOLOGY; 33 2363-2368.
Chem Codes: Chemical of Concern: DZ Rejection Code: SURVEY.

BIOSIS COPYRIGHT: BIOL ABS. The Axios River Basin is one of the most developed agricultural areas of Greece. Samples from a total of 205 rain events collected from eight sampling stations during 1997-1998 were analyzed for pesticide residues of which 186 events (90%) yielded at least one positive detection. Among 160 target pesticides and some major conversion products recovered by solid-phase extraction (SPE) and analyzed by GC-ITMS, 47 compounds were found in at least one rain event. The most frequently found pesticides idual compound ranged from 0.002 to 6.82 mug. Greater pesticide concentrations occurred during application seasons. The estimated annual deposition rates for the sum of the pesticides ranged from 51 to 395 mug/m2 of soil surface. Air Pollution/ Soil Pollutants/ Water Pollution

Chatterjee, K. (1975). Toxicity of Diazinon to Fish and Fish Food Organisms. Indian Sci.Congr.Assoc.Proc. 62: 166-167.

EcoReference No.: 7511

Chemical of Concern: DZ; Habitat: A; Effect Codes: MOR; Rejection Code: NO ABSTRACT.

Chatterjee, K. and Konar, S. K. (1984). Effects of the Pesticide Diazinon at Various pH and Turbidity on Fish and Aquatic Ecosystem. Aquat.Sci.Fish.Abstr.14(11, Pt.1):263 / Environ.Ecol. 2: 49-53.

EcoReference No.: 11693

Chemical of Concern: DZ; Habitat: A; Effect Codes: GRO; Rejection Code: NO ABSTRACT.

Chattopadhyay, Amitabha (1990). Chemistry and biology of N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-labeled lipids: fluorescent probes of biological and model membranes. Chemistry and Physics of Lipids 53: 1-15.

Chem Codes: Chemical of Concern: DZ Rejection Code: METHODS.

Lipids that are covalently labeled with the 7-nitrobenz-2-oxa-1,3-diazol-4-yl (NBD) group are widely used as fluorescent analogues of native lipids in model and biological membranes to study a variety of processes. The fluorescent NBD group may be attached either to the polar or the apolar regions of a wide variety of lipid molecules. Synthetic routes for preparing the lipids, and spectroscopic and ionization properties of these probes are reviewed in this report. The orientation of various NBD-labeled lipids in membranes, as indicated by the location of the NBD group, is also discussed. The NBD group is unchanrged at neutral pH in membranes, but loops up to the surface if attached to acyl chains of phospholipids. These lipids find applications in a variety of membrane-related studies which include membrane fusion, lipid motion and dynamics, organization of lipids and proteins in membranes, intracellular lipid transfer, and bilayer to hexagonal phase transition in liposomes. Use of NBD-labeled lipids asanalogues of natural lipids is critically evaluated. NBD-labeled lipid/ model membrane/ fluorescence/ resonance energy transfer/ location/ ionization

Chattopadhyay, Amitabha and London, Erwin (1988). Spectroscopic and ionization properties of N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-labeled lipids in model membranes. Biochimica et Biophysica Acta (BBA) - Biomembranes 938: 24-34.
Chem Codes : Chemical of Concern: DZ Rejection Code: METHODS.

The spectroscopic and ionization properties of various lipids labeled with the 7-nitrobenz-2-oxa-1,3-diazol-4-yl (NBD) group have been studied in model membranes using fluorescence, absorbance and electrophoretic mobility measurements. Electrophoretic measurements show that the NBD group is uncharged at neutral pH. However, at high pH, hydroxyl addition or deprotonation occurs with a pKa, depending upon conditions, of 11.5-11.8 for the NBD group of headgroup-labeled phosphatidylethanolamine (NBD-PE) and 11.1-11.5 for NBD labels placed at the end of one fatty acyl chain of a phosphatidylcholine (6-NBD-PC and 12-NBD-PC). This type of behavior is not observed in the case of a methylated NBD label placed in the flexible ‘tail’ of cholesterol (NBD-cholesterol). The similarity in pKa for NBD-PE and NBD-PCs suggests that in these cases the NBD group is at a similar depth in the membrane. This was examined further by comparison of the fluorescence emission maximum of the NBD group in model membranes with that in solvents of varying polarity. The apparent polarity experienced by NBD groups in model membranes indicates that for NBD-PE and 12-NBD-PC they are located at the polar region whereas the NBD group of NBD-cholesterol is deeply buried in a nonpolar region of the membrane. This conclusion is supported further by fluorescence quenching experiments measuring NBD exposure to the aqueous quencher Co2+. The results of this study confirm the tentative conclusions of our previous fluorescence quenching studies on the location of NBD groups in model membranes. Model membrane/ NBD-labeled lipid/ Fluorescence quenching/ Electrophoretic mobility/ Absorbance/ Membrane penetration depth

Chen, Chien-An, Yeh, Ren-Hwa, Yan, Xiongwei, and Lawrence, David S. (2004). Biosensors of protein kinase action: from in vitro assays to living cells: IPK'2003. Inhibitors of protein kinases and Workshop: Phosphoryl-transfer mechanisms. Biochimica et Biophysica Acta (BBA) - Proteins & Proteomics 1697: 39-51.
Chem Codes: Chemical of Concern: DZ Rejection Code: METHODS.

Protein kinases, and the signal transduction pathways in which they participate, are now recognized to be medicinally attractive targets of opportunity. Inhibitors of the protein kinase family not only hold great promise as therapeutic agents, but are also of profound utility in the characterization of signaling pathways. The direct visualization of protein kinase activity in living cells provides a genuine assessment of the efficacy and selectivity of these inhibitors in a physiological setting. In addition, the ability to visualize the activity of a protein kinase in real time furnishes a direct measurement of the activation of specific signaling pathways in response to extracellular stimuli. We have developed two series of fluorescent substrates for protein kinase C (PKC) using a strategy that positions the reporter-group directly on the residue undergoing phosphorylation. The first series of PKC substrates is based, in part, on the Ca+2 indicators developed by Tsien and his collaborators during the 1980s. In this case, phosphorylation of the substrate creates a divalent metal ion binding site. Upon metal ion coordination, a fluorescence change transpires via a mechanism analogous to that described for the Ca+2 indicators. The second series of PKC sensors was identified via the preparation and subsequent screen of a library of fluorescently-labeled PKC peptide substrates. The lead derivative displays a phosphorylation-induced fluorescence change that allows the visualization of real-time PKC activity in both cell lysates and living cells. Furthermore, immunodepletion experiments demonstrate that the fluorescently-tagged peptide is selectively, if not exclusively, phosphorylated by the conventional PKCs. Both of the protein kinase biosensor strategies take advantage of the ease with which peptides can be modified to create libraries of structurally altered analogs. However, the inherent synthetic mutability of peptides is not just limited to library construction. For example, it may ultimately be possible to simultaneously monitor multiple protein kinases by affixing fluorophores with distinct photophysical properties to appropriately designed active site-directed peptides. Author Keywords: Protein kinase sensor/ Combinatorial library/ Consensus sequence/ Protein kinase substrate/ Signal transduction

Chen, D., Rolston, D. E., and Yamaguchi, T. (2000). Calculating partition coefficients of organic vapors in unsaturated soil and clays. Soil Science, 165 (3) pp. 217-225, 2000.
Chem Codes: Chemical of Concern: DZ Rejection Code: METHODS.

ISSN: 0038-075X

Descriptors: Partition coefficients of organic vapors
Descriptors: Adsorption
Descriptors: Volatile organic compounds
Descriptors: Pesticides
Abstract: Sorption of organic vapors on soil increases dramatically as soil-water content decreases in a dry region. Equations for calculating organic vapor partition coefficients in unsaturated soils as a function of soil-water content are proposed. The equations were based on the hypothesis that organic vapor in soils are found adsorbed onto water-solid and air-solid interfaces and dissolved in the soil solution. In the dry range, where water in soils can be considered the sorbate, water vapor and organic vapor compete for sorption sites with water vapor adsorbed preferentially at the air-solid interfaces because of the higher polarity of water molecules. The air-solid interfaces that are not covered by water molecules and are available for sorption of organic vapor can be estimated according to the Brunauer-Emmett-Teller adsorption theory. The predictions made by the proposed equations were compared with partition coefficients of three volatile organic compounds (VOCs)-benzene, toluene, and trichloroethylene-and a pesticide, diazinon (O,O diethyl O-(2-isopropyl-4-methyl-6-pyrimidinyl) phosphorothioate) in Yolo silt loam, and with partition coefficients of the same three VOCs for two clay minerals. The measured and predicted partition coefficients agreed reasonably well. All parameters of the proposed equations are measurable, and no curve-fitting is needed.
32 refs.
Language: English
English
Publication Type: Journal
Publication Type: Article
Country of Publication: United States
Classification: 92.10.1.4 CROP SCIENCE: Crop Physiology: Soil science
Subfile: Plant Science

Chen, P. S., Lin, Y. N., and Chung, C. L. (1971). Laboratory Studies on the Susceptibility of Mosquito-Eating Fish, Lebistes reticulatus and the Larvae of Culex pipiens fatigans to Insecticides. Tai-Wan I.Hsueh Hui Tsa Chih 70: 28-35.

EcoReference No.: 9297

Chemical of Concern: CBL,DZ,HCCH,MLN,DDT,PRN; Habitat: A; Effect Codes: MOR; Rejection Code: NO CONTROL(ALL CHEMS).

Chen, W., Poon, K. F., and Lam, M. H. W. (1998). The application of solid phase microextraction in the analysis of organophosphorus pesticides in a food plant. Environmental Science and Technology, 32 (23) pp. 3816-3820, 1998.

Chem Codes: Chemical of Concern: DZ Rejection Code: METHODS.

ISSN: 0013-936X

Abstract: A SPME method for the determination of organophosphorus pesticide residues in a local food plant, Chrysanthemum coronarium, was established. Pesticide residues were extracted by SPME fiber (with 100 mu m poly(dimethylsiloxane) coating) from a biphasic water /plant tissues mixture and determined by GC-FPD. An equilibrium model was derived for the system and revealed that pesticide recoveries were related to the water:plant tissues ratio, f, and the partition coefficient, K(WV), for the distribution of pesticides between the aqueous phase and the plant tissues. The model was verified by four organophosphorus pesticides, namely phorate, diazinon, methyl parathion, and ethion. The best fitted K(WV) values (P less than 0.05) for the pesticides were found to be 4.73 plus-or-minus 0.32 x 10 superior - superior 2 (phorate); 1.11 plus-or-minus 0.10 x 10 superior - superior 1 (diazinon); 9.18 plus-or-minus 0.95 x 10 superior - superior 2 (methyl parathion); and 8.21 plus-or-minus 1.28 x 10 superior - superior 3 (ethion). Remarkable correlation between the K(WV) of the organophosphorus pesticides and their octanol/water partition coefficients, K(OW), was also established.
33 refs.
Language: English
English
Publication Type: Journal
Publication Type: Article
Country of Publication: United States
Classification: 92.10.4.9 CROP SCIENCE: Crop Protection: Chemical residues
Subfile: Plant Science

Chen, Youcun, Liu, Guangxiang, Song, You, Xu, Heng, Ren, Xiaoming, and Meng, Qingjin (2005). Molecular spin ladders self-assembly from [Ni(dmit)2]- building blocks: Syntheses, structures and magnetic properties: Proceedings of the 9th International Conference on Molecule-based Magnets (ICMM 2004). Polyhedron 24: 2269-2273.

Chem Codes: Chemical of Concern: DZ Rejection Code: METHODS.

Bis(2-thioxo-1,3-dithion-4,5-dithiolato)nickelate compound/ Crystal structure/ Magnetic property/ Spin ladder Two ion-pair compounds, consisting of 1-(4'-R-benzyl)pyridinium ([RBzPy]+, R = NO2 (1) and Br (2)) and [Ni(dmit)2]- (dmit2- = 2-thioxo-1,3-dithion-4,5-dithiolato), have been synthesized and structurally characterized. The anions of [Ni(dmit)2]- stack into dimers, which further construct into two-leg ladder through terminal S...S interactions in 1, lateral S...S interactions in 2. The weak H-bonding interactions of C-H...S were observed in 2, while only weak van de Waals interactions between anion and cations in 1. The magnetic susceptibilities measured in 2-300 K indicate AFM exchange interaction domination both two compounds. A peculiar magnetic transition at ~100 K was observed in 1. An AFM ordering below ~11 K was found in 2, and the best fit to magnetic susceptibility above 45 K in this compound, using a dimer model with s = 1/2, give rise to [Delta]/kB = 36.1 K, zJ = -0.91 K, C = 3.2 x 10-3 emu K mol-1 and [chi]0 = -4.0 x 10-6 emu mol-1 with g of 2.0 fixed.

Chennamaneni, Srinivas Rao, Vobalaboina, Venkateswarlu, and Garlapati, Achaiah (2005). Quaternary salts of 4,3' and 4,4' bis-pyridinium monooximes: Synthesis and biological activity. Bioorganic & Medicinal Chemistry Letters 15: 3076-3080.
Chem Codes: Chemical of Concern: DZ Rejection Code: METHODS.

Organophosphate/ Pesticide/ TEPP/ Brain acetycholinesterase/ 2-PAM/ Bis-pyridinium monooximes/ Reactivation Six unsymmetrical bis-quaternary monooximes viz. dibromides of 1-(4-hydroxyiminomethyl pyridinium)-3-(3/4-carbamoyl pyridinium)propane, 1-(4-hydroxyiminomethyl pyridinium)-4-(3/4-carbamoyl pyridinium) butane, 1-(4-hydroxyiminomethyl pyridinium)-5-(3/4-carbamoyl pyridinium)pentane were synthesized and characterized by spectral data. Their ability to reactivate tetraethyl pyrophosphate inhibited mouse total brain cholinesterase was investigated and compared with 2-pyridine aldoxime chloride (2-PAM). All the compounds were found to be more effective acetylcholinesterase reactivators when compared with the conventional oxime, 2-PAM, except the compound (5a) with pentylene bridge and carbamoyl group present at fourth position. The bis-pyridinium monooximes with 3-carbamoyl group were more potent reactivators than the corresponding 4-carbamoyl compounds and bis-oximes tested.

Chernomordik, Leonid V., Sokolov, Alexander V., and Budker, Vladimir G. (1990). Electrostimulated uptake of DNA by liposomes. Biochimica et Biophysica Acta (BBA) - Biomembranes 1024: 179-183.
Chem Codes: Chemical of Concern: DZ Rejection Code: METHODS.

High molecular mass DNA was efficiently taken up by large unilamellar vesicles exposed to a short pulse of electric field (0.1-1 ms) with an intensity as high as 12.5 kV/cm. The efficiency of uptake increased significantly in presence of Mg2+ ions and was approximately 0.6 and 1.5 [mu]g of DNA per [mu]mol of lipid for T7 DNA and plasmid pBR 322, respectively. The results presented indicated that DNA was taken up as a result of the electrostimulated formation of endosome-like vesicles rather than via field-induced membrane pores. Electrostimulation/ DNA transfer/ Liposome

CHERNYAK SM, RICE CP, and MCCONNELL LL (1996). Evidence of currently-used pesticides in air, ice, fog, seawater and surface microlayer in the Bering and Chukchi seas. MARINE POLLUTION BULLETIN; 32 410-419.
Chem Codes: Chemical of Concern: DZ Rejection Code: NO TOX DATA.

BIOSIS COPYRIGHT: BIOL ABS. Investigation of currently-used pesticides (triazines, acetanilides, organophosphates and organochlorines) was carried out in the Bering and Chukchi marine ecosystems in the summer of 1993. Chlorpyrifos and trace levels of endosulphan were the most frequently identified contaminants in seawater, chlorpyrifos and atrazine were found in marine ice, and chlorothalonil and trifluralin were found in surface microlayer samples. Concentrations of chlorpyrifos were highest (170 ng l-1) in marine ice and higher in seawater (19-67 ng l-1) at locations which were closest to the ice edge. Endosulphan was found as a widely distributed currently used pesticide in the polar atmosphere. The greatest concentration of any one single agrochemical was trifluralin (1.15 mug l-1) in a Bristol Bay surface microlayer sample. Arctic marine fog was sampled and for the first time, several currently-used pesticides (chlorpyrifos, trifluralin, metolachlor, chlorothalonil, terbufos and endosulphan) Climate/ Ecology/ Meteorological Factors/ Ecology/ Oceanography/ Biochemistry/ Air Pollution/ Soil Pollutants/ Water Pollution