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Journal of Toxicology and Environmental... 1981Induction of sister chromatid exchanges (SCEs) in cultures of Chinese hamster ovary cells by 10 anticholinesterase organophosphate insecticides was investigated. The...
Induction of sister chromatid exchanges (SCEs) in cultures of Chinese hamster ovary cells by 10 anticholinesterase organophosphate insecticides was investigated. The insecticides were two phosphates (dichlorvos and dicrotophos), four sulfur-containing organophosphates (malathion, parathion, leptophos, and diazinon), and four oxygen analogs of the latter (malaoxon, paraoxon, leptophosoxon, and diazoxon). All of the compounds except diazinon induced statistically significant increases in SCE frequencies at concentrations between 0.03 and 1.0 mM. These results suggest that SCE induction is a common property of organophosphate insecticides. Compared to the sulfur-containing organophosphates, the oxygen analogs consistently produced higher SCE frequencies and had stronger antiproliferative activity. Compared to two known genotoxicants, doxorubicin and ethyl methanesulfonate, the ability of organophosphates to produce SCEs is much weaker.
Topics: Animals; Cells, Cultured; Chromosome Aberrations; Cricetinae; Cricetulus; Crossing Over, Genetic; Female; Insecticides; Mutagens; Organophosphorus Compounds; Organothiophosphorus Compounds; Ovary; Sister Chromatid Exchange
PubMed: 7338954
DOI: 10.1080/15287398109530128 -
Journal of Toxicology and Environmental... 1981Oral doses of the organophosphorus pesticides acephate, dicrotophos, fensulfothion, fonofos, malathion, and parathion were administered to mallard ducklings (Anas...
Oral doses of the organophosphorus pesticides acephate, dicrotophos, fensulfothion, fonofos, malathion, and parathion were administered to mallard ducklings (Anas platyrhynchos), and brain and plasma cholinesterase (ChE) activities were determined for up to 17 d after dosing. In vivo recovery of brain ChE activity to within 2 standard deviations of the mean activity of undosed birds occurred within 8 d, after being depressed an average of 25-58% at 24 h after dosing. In vivo recovery of plasma ChE appeared as fast as or faster than that of brain, but the pattern of recovery was more erratic and therefore statistical comparison with brain ChE recovery was not attempted. In vitro tests indicated that the potential for dephosphorylation to contribute to in vivo recovery of inhibited brain ChE differed among chemical treatments. Some ducklings died as a result of organophosphate dosing. In an experiment in which ducklings within each treatment group received the same dose (mg/kg), the brain ChE activity in birds that died was less than that in birds that survived. Brain ChE activities in ducklings that died were significantly different among pesticide treatments: fensulfothion greater than parathion greater than acephate greater than malathion (p less than or equal to 0.05).
Topics: Animals; Brain; Cholinesterases; Ducks; Insecticides; Organophosphorus Compounds
PubMed: 7338949
DOI: 10.1080/15287398109530123 -
Teratology Apr 1981A comparative qualitative and quantitative study of the embryotoxic and teratogenic activities of various chemical agents known to have neuromuscular blocking properties... (Comparative Study)
Comparative Study
A comparative qualitative and quantitative study of the embryotoxic and teratogenic activities of various chemical agents known to have neuromuscular blocking properties was done on the quail embryo. Intrinsic embryotoxic activity and teratogenicity were evaluated for each agent, and the qualitative nature of the teratogenic effects was correlated with the pharmacologic properties of the different effectors. Gross malformations (contorted posture) were found only with agents which directly (cholinergic agonists) or indirectly (cholinesterase inhibitors) favor muscle membrane depolarization, suggesting that such malformations may be due to muscle contraction following depolarization. All of the agents studied produced variable degrees of vertebral fusion, apparently due to paralysis resulting either from sustained depolarization (cholinesterase inhibitors and cholinergic agonists) or directly from cholinergic blockade (cholinergic antagonists and neurotoxins).
Topics: Abnormalities, Drug-Induced; Animals; Bungarotoxins; Carbachol; Coturnix; Decamethonium Compounds; Drug Evaluation, Preclinical; Gallamine Triethiodide; Hexamethonium Compounds; Muscles; Neostigmine; Neuromuscular Blocking Agents; Nicotine; Organophosphorus Compounds; Parathion; Physostigmine; Quail; Quaternary Ammonium Compounds; Teratogens; Tubocurarine
PubMed: 7196602
DOI: 10.1002/tera.1420230211 -
Archives of Environmental Contamination... 1981Brain and plasma cholinesterase (ChE) activities were determined for mallard ducklings (Anas platyrhynchos) exposed to dicrotophos and fenthion. Recovery rates of brain...
Brain and plasma cholinesterase (ChE) activities were determined for mallard ducklings (Anas platyrhynchos) exposed to dicrotophos and fenthion. Recovery rates of brain ChE did not differ between ducklings administered a single oral dose vs. a 2-week dietary dose of these organophosphates. Exposure to the organophosphates, followed by recovery of brain ChE, did not significantly affect the degree of brain ChE inhibition or the recovery of ChE activity at a subsequent exposure. Recovery of brain ChE activity followed the general model Y = a + b(logX) with rapid recovery to about 50% of normal, followed by a slower rate of recovery until normal ChE activity levels were attained. Fenthion and dicrotophos-inhibited brain ChE were only slightly reactivated in vitro by pyridine-2-aldoxime methiodide, which suggested that spontaneous reactivation was not a primary method of recovery of ChE activity. Recovery of brain ChE activity can be modeled for interpretation of sublethal inhibition of brain ChE activities in wild birds following environmental applications of organophosphates. Plasma ChE activity is inferior to brain ChE activity for environmental monitoring, because of its rapid recovery and large degree of variation among individuals.
Topics: Animals; Brain; Cholinesterase Reactivators; Cholinesterases; Ducks; Insecticides; Organophosphorus Compounds; Time Factors
PubMed: 7224673
DOI: 10.1007/BF01055623 -
Journal of Toxicology and Environmental... Jul 1980Organophosphorus pesticides have generally low persistence in the environment, but they may persist in water and accumulate in certain aquatic vertebrates. Frogs are...
Organophosphorus pesticides have generally low persistence in the environment, but they may persist in water and accumulate in certain aquatic vertebrates. Frogs are resistant to cholinesterase inhibitors; thus it was suspected that they might accumulate the pesticides. Tadpoles concentrated pesticides from water up to 60 times; those exposed to 1 ppm parathion and 5 ppm fenthion were lethal when they were fed to mallard ducks. Dicrotophos, malathion, and acephate were not accumulated to levels such that they were lethal when consumed in a single meal by ducks. Brain cholinesterase levels were correlated with dose and effect. Metabolites of parathion and fenthion produced by the tadpoles were rapidly excreted and it was concluded that they play a small role in the toxicity of the larvae to ducks. Dangerous levels of some pesticides may be accumulated by amphibians in nature and may adversely affect carnivorous species.
Topics: Animals; Cholinesterases; Ducks; Insecticides; Organophosphorus Compounds; Organothiophosphorus Compounds; Rana catesbeiana; Tissue Distribution; Water
PubMed: 6968357
DOI: 10.1080/15287398009529903 -
Journal of Environmental Pathology and... 1980Diisopropylfluorophosphate has been reported to cause an early inhibition of proteosynthesis in the spinal ganglia of cats. If organophosphorus compounds can cause a...
Diisopropylfluorophosphate has been reported to cause an early inhibition of proteosynthesis in the spinal ganglia of cats. If organophosphorus compounds can cause a partial blockage of protein synthesis, normal turnover of neuronal proteins could establish conditions similar to those which ocur in Wallerian degeneration. In this study neuroblastoma 2-A cells, a homogenous cell system which exhibits many of the functional properties of normal neurons, was used to establish dose-response relationships of three organophosphorus compounds: Tri-o-tolyl-phosphate (TOTP), Diisopropylfluorophosphate (DFP) and dicrotophos. The incorporation of 14C from glucose was used as an indicator of metabolic activity and the incorporation of L-leu-cine-14C as an indicator of proteosynthetic activity. The rates of incorporation of labeled precursors as effected by three dose levels of each organophosphorus compound were measured in logarithmically growing cells and in cells in a stationary growth phase in media without serum. The cells were also observed under phase-contrast microscopy. The organophosphorus compounds caused the neurites to have a shrunken, rough and irregular appearance. Swelling along the length of the neurites were also observed, especially with the DFP-treated cells. All three compounds caused a dose-related reduction in the accumulation of 14C activity from glucose which was probably a measure of cytotoxicity. DFP and TOTP caused an inhibition of the uptake of leucine-14C while dicrotophos did not. The results suggest that neurotoxic organophosphate compounds depress the rate of protein synthesis which may be responsible for the degenerative syndrome.
Topics: Animals; Cell Survival; Cells, Cultured; Glucose; Isoflurophate; Leucine; Mice; Neoplasm Proteins; Neoplasms, Experimental; Nerve Tissue Proteins; Neuroblastoma; Neurons; Organophosphorus Compounds; Tritolyl Phosphates
PubMed: 7441094
DOI: No ID Found -
Acta Embryologiae Et Morphologiae... Apr 1980
Topics: Abnormalities, Drug-Induced; Animals; Chick Embryo; Insecticides; Organophosphorus Compounds
PubMed: 7324789
DOI: No ID Found -
JPMA. the Journal of the Pakistan... Feb 1980
Topics: Adult; Agriculture; Electrocardiography; Humans; Insecticides; Male; Myocarditis; Occupational Diseases; Organophosphate Poisoning; Organophosphorus Compounds
PubMed: 6770120
DOI: No ID Found -
Tropical Animal Health and Production Feb 1980This paper describes the susceptibility of various samples of Boophilus microplus from the southern region of Minas Gerais State in Brazil to the 4 commonest...
This paper describes the susceptibility of various samples of Boophilus microplus from the southern region of Minas Gerais State in Brazil to the 4 commonest organophosphorus acaricides employed in the area. All samples showed some degree of resistance to each of the compounds used. The resistance factor varied from 1.42 to 132.90, being less in the case of dicrotophos fenthion than with chlorpyrifos and coumaphos.
Topics: Animals; Brazil; Chlorpyrifos; Coumaphos; Female; Fenthion; Insecticides; Organophosphorus Compounds; Ticks
PubMed: 6154364
DOI: 10.1007/BF02242623 -
Journal of the South African Veterinary... Dec 1979A series of in vitro trials using unfed larvae and fully fed adult ticks confirmed ixodicidal resistance in the one-host Pantropical Blue Tick, Boophilus microplus... (Comparative Study)
Comparative Study
A series of in vitro trials using unfed larvae and fully fed adult ticks confirmed ixodicidal resistance in the one-host Pantropical Blue Tick, Boophilus microplus (Canestrini). Fifty-seven of 64 field isolates were resistant to arsenic; 10 of 56 were resistant to toxaphene; 1 of 5 were resistant to lindane; 3 of 5 were resistant to dieldrin; 3 of 19 were resistant to DDT and 8 of 55 were resistant to the organophosphorus ixodicide, dioxathion. One of the field isolates resistant to dioxathion was also highly resistant to the carbamate, carbaryl, and to the organophosphorus ixodicides benoxophos and diazinon. A second was resistant to the organophosphorus ixodicides benoxophos, diazinon, carbophenothion, dicrotophos, ethion, fenitrothion and quintiofos. Low levels of resistance, less than 3X, were shown to chlorfenvinphos and coumaphos. No resistance was shown to chlorpyrifos, bromophos ethyl or the diamidine ixodicide, amitraz. In hand-spraying trials no variation in the susceptibility of an organophosphorus resistant strain or the susceptible laboratory strain to amitraz was observed. This is the first recorded resistance to ixodicides by B. microplus in Africa.
Topics: Animals; Cattle; Female; Insecticide Resistance; Larva; South Africa; Ticks
PubMed: 553968
DOI: No ID Found