Organic Phosphate Insecticides Research Articles

MALATHION POISONING TREATED WITH PROTOPAM,.

Case Studies1 May 1965Malathion Poisoning Treated with ProtopamWILLIAM C. AMOS JR., M.D., ALLAN HALL, M.D.WILLIAM C. AMOS JR., M.D.Search for more papers by this author, ALLAN HALL, M.D.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-62-5-1013 SectionsAboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail ExcerptDuring the past year, our attention was directed toward the management of a case of organic phosphate toxicity caused by the insecticide malathion. Although there are many reports pertaining to poisonings of this type, a review of the American literature reveals only six previously reported cases of malathion intoxication (1-6). All of these patients were children, and in only two was poisoning a result of oral ingestion. The patient to be presented differs in that he was a teenager who poisoned himself attempting suicide. Of the various organic phosphate insecticides, malathion is commonly seen in the home, as it has...

BLOOD CHOLINESTERASE LEVELS IN ORGANIC PHOSPHATE INTOXICATION.

The inhibition of cholinesterase (ChE) activity by the organic phosphate insecticides provides a sensitive indicator of absorption of these compounds. In order to interpret the laboratory results of the ChE activity, one must consider several factors, including the accuracy of the determination. Unless the laboratory personnel are accustomed to performing the analysis (Michel method), a duplicate sample should be sent to a laboratory where the test is commonly done for comparison. Blood is collected in a heparinized capillary tube, and the plasma and red blood cells (RBC) are separated as soon as possible. The test may be performed with as little as 0.02 ml of heparinized blood. 1 Since there is a 100% variation in the normal ChE activity among different individuals, and since the same person may show a variation of as much as 25% at different times, it is extremely helpful if the normal values for the individual

Control of Hunting Billbugs

The hunting billbug, Sphenophorus venatus vestita (Chttn.) is widespread in the eastern United States. It will feed on many kinds of grasses, although in Florida it has been of importance almost exclusively on zoysiagrass. Occasionally, damaging numbers have occurred in Bermudagrass. This billbug is not a major turf pest in Florida, but it is a continuing serious problem in zoysiagrass nurseries. Kelsheimer (1956) first reported the hunting billbug as a pest in Florida nurseries, and described the injury it causes. Kerr (1959), reporting on test work in a turf nursery, stated that the organic phosphorous insecticides were superior to chlorinated hydrocarbons, and that phorate appeared to give the best control. Nemacide and carbophenothion have also been used for control, but growers have commented that none of these three materials has given the high degree of control they would like to achieve. Accordingly, further test work was set up in the winter of 1963-64.

The Toxicity of Some Pesticide Residues to Adult Amblyseius hibisci, with a Compilation of the Effects of Pesticides upon Phytoseiid Mites

The effects of the residues of 62 commercial pesticides upon the predatory phytoseiid mite, Amblyseius hibisci (Chant), were examined in the laboratory to obtain information on how this species may be protected in integrated chemical and biological control programs, and how the effectiveness of this predator May be measurted with pesticidal check procedures, i.e. by the host increase arising from the predator's elimination by pesticides. Methods of handling, feeding, and testing the adult mites are described. Laboratory test results on adult A. hibisci are presented along with a list of published laboratory and field reports on the effects of the same toxicants upon other species of phytoseiids. Almost all the organic phosphate and carbamate insecticides tested were moderately to highly toxic. Considerable tolerance was shown by the adults to 2 of the chlorinated hydrocarbons, 4 of the acaricides, 3 of the stomach poisons, and 4 of the fungicides tested. Conflicting reports of pesticide effects upon other phytoseiids emphasize the variability in response to be expected with different species of this group. Subjects discussed are pesticide specificity to phytoseiids, characterization of pesticides causing destruction of phytoseiids, potential integrated control or pesticidal check materials, and apparent associations between phytoseiid destruction and the increase of phytophagous mites.

The inheritance of diazinon resistance in an Australian strain of Musca domesticaL.

The genetics of diazinon resistance in an Australian strain of Musca domestica L. was investigated by means of two series of repeated back-crosses of the hybrid resistant form to the susceptible. Resistance was maintained through nine and eleven generations in the separate studies. The ratio of susceptible to resistant hybrid flies found in the progeny of each cross was approximately 1:1.In the second series, the frequency data were supported by dosage/response information on the relationship between dosage of insecticide and mortality. Together with the result of a previous study, the data furnish strong evidence that a fully dominant factor is responsible for the diazinon resistance in the Perth strain of house-flies resistant to organic phosphate insecticides.

Field Resistance of Horn Flies to the organic Phosphate Insecticide Ronnel

Field Resistance of Horn Flies to the organic Phosphate Insecticide Ronnel

Mole Cricket Control in Shade Tobacco Plant Beds

The Southern mole cricket, Scapteriscus acletus Rehn and Hebard, and the changa, S. vicinus Scudder, have long been recognized as pests in tobacco plant beds in the Quincy, Florida, area, with the Southern mole cricket being the more prevalent species. Chamberlin and Madden (1942) observed that mole crickets were increasing in importance as plant bed pests, causing little damage by actual feeding on plants, but some injury from burrowing in the soil layer subjacent to the soil surface. Tobacco seedlings in the soil layer superjacent to the burrows often died from lack of moisture caused by the disruption of capillarity existing between the water table and the soil surface. Not only did the burrowing cause death of plants, but it caused the soil to become so desiccated that seed failed to germinate. Damage by these pests was counteracted by use of overhead irrigation to return the soil to its original position or by compacting the soil into position by pressing the raised burrows with the foot or some improvised tamping tool. These methods were laborious and unsatisfactory; therefore, insecticidal control measures were indicated. The first economic mole cricket control developed for shade tobacco consisted of a bait containing a stomach poison of either calcium arsenate or paris green (Chamberlin and Madden, 1942). Although this bait gave satisfactory control at that time, its effectiveness as a stomach poison depended to a large extent upon the actual feeding of the mole crickets upon the bait. Later, sodium fluosilicate proved to be satisfactory as a stomach poison in a bait (Wisecup and Hayslip, 1953). Control with contact poisons became a reality with the advent of organic chlorinated-hydrocarbon and phosphate insecticides in the 1940's. Kelsheimer (1950), working with vegetables and other crop plants, found that chlordane wettable powder or emulsifiable concentrate incorporated into the soil prior to seeding of plant beds gave excellent protection from mole crickets. However, the bait method persisted because it was economical and had the prestige of established grower usage (Reid and Cuthbert, 1955; Kuitert and Tissot, 1956; and Guthrie, et al., 1958). Although baits continued to be recommended, the toxic ingredient was changed to chlordane, which also acts as a contact poison if, or when, enough bait is broadcast onto a plant bed. Guthrie et al. (1958) recommended using a drench containing parathion for fluecured tobacco plant beds. In shade-tobacco plant beds, control of all insects is based upon prevention of damage to insure an adequate supply of healthy insect-free plants of uniform size for transplanting in the field. The prevention of all insect damage is not always obtained, as is often the case in a control program of this type, but shade tobacco growers continually strive for that degree of perfection in order to glean the highest monetary return from their crop. Observations prior to 1958 indicated that the critical mole cricket control period in plant beds was approximately 40 to 50 days from seeding, de-

Electrophoretic properties of esterases from susceptible and resistant strains of the housefly, Musca domestica L.

The soluble esterases from six strains of the housefly have been separated by electrophoresis in partially hydrolysed starch gel, according to the technique of Smithies. The separated enzymes were then classified as cholinesterases, aliesterases, and aromatic esterases by use of a series of specific inhibitors. A detailed study with a susceptible and a malathion-resistant strain showed marked differences in amount and migratory behaviour in the various stages of the life cycle but no pattern characteristic of resistance. A semi-quantitative correlation was found between the synergistic effects of a group of non-insecticidal organic phosphates and their inhibitory effects upon the cholinesterases and aliesterases of the two strains. The enzymes hydrolysing naphthyl acid phosphate are more numerous and more active in the malathion-resistant strain. The results lend support to the theory that resistance to organic phosphate insecticides such as malathion is related to higher phosphatase activity.

Clothing-borne epidemic. Organic phosphate poisoning in children.

Six children in Fresno, Calif., were poisoned by wearing unwashed jeans that had been contaminated by an organic phosphate insecticide (Phosdrin) while in shipment 8 mo earlier. Two cases are presented in detail. These had positive urine sugar tests and leukocytosis. The diagnosis was confirmed in each case by cholinesterase determinations and by the response to therapy which included atropine and pralidoxime chloride. Prompt action by the public health department resulted in recovery of the rest of the contaminated shipment even though they had all been sold to an unsuspecting public.

Insecticides for the Control of the Green Peach Aphid on Shade-Grown Tobacco1

From 1956 through 1961, 24 insecticidal and two primarily fungicidal materials were evaluated at Quincy, Florida, for control of the green peach aphid. Myzus persicae (Sulzer), on shade-grown tobacco. Weekly applications of 4% Diazinon® (O, O-diethyl O-(2-isopropyl-4-1-methyl-6-pyrimidinyl) phosphorothioate), 1.5% Phosdrin® (a mixture of the alpha isomer of 2-carbomethoxy-1-methylvinyl dimethyl phosphate (not less than 60%) and related compounds (not more than 40%)), 4% Thiodan® (6, 7, 8, 9, 10, 10-hexachloro-1, 5, 5a, 6, 9, 9a-hexahydro-6, 9-methano-2, 4,3-benzodioxathiepin-3-oxide), or 3% Trithion® (O, O-diethyl S-p-chlorophenylthiomethyl phosphorodithioate) showed considerable promise as possible substitutes for 1% parathion. Two per cent endrin, 5% malathion, or 1.5% Telodrin® (1,3,4,5.6,7,8, 8-octachloro-1,3,3a,4,7,7a-hexahydro-4,7-methanoisobenzofuran applied weekly gave commercial control; however, the three materials were not so efficient as 1% parathion. Applications of 1% parathion at 2-week intervals decreased injurious aphid populations and maintained effective control. Results indicated that absolute or 100% control was not essential to guarantee a commercially successful crop. Although resistance by this aphid to organic phosphate insecticides has been reported on various crops in other localities, no evidence of resistance was found on tobacco in the Quincy area.

Selection for a Fluoroacetate Resistant Strain of House Flies and Investigation of Its Resistance Pattern1

A susceptible strain of the house fly ( Musca domestica L.) was selected with f1uoroacetate. After 25 generations a 7-fold resistance developed as measured by drop feeding. Simultaneously high resistance to chlorinated hydrocarbon insecticides was observed. The flies remained susceptible to organic phosphate insecticides, Sevin® (I-naphthyl N -methylcarbamate) and a Sevin piperonyl butoxide combination. When selection with fluoroacetate was discontinued the high levels of chlorinated hydrocarbon resistance remained for at least eight generations. The fluoroacetate-selected flies also developed vigor tolerance as measured by their increased resistance to starvation and lack of water.

Differential Susceptibility of Maggots of Several Species to Droppings from Chickens Fed Insecticide-Treated Rations1

The susceptibility of larvae of Musca domestica L., Fannia pusio (Wiedemann), Chrysomya megacephala (F.), and Parasarcophaga argyrostoma (Robineau-Desvoidy) to droppings from poultry given feed containing the following 22 insecticides was determined: American Cyanamid 12008 (O,O-diethyl S-(isopropylthio) methyl phosphorodithioate), American Cyanamid 18706 (O,O-dimethyl S-(N-ethylcarbamoylmethyl) phosphorodithioate), Bayer 22408 (O,O-diethyl O-naphthalimido phosphorothioate), Bayer 25141 (O,O-diethyl O-p-methylsulfinylphenyl phosphorothioate), Bayer 29493 (O,O-dimethyl O-[4-methylthio)-m-tolyl] phosphorothioate), butonate (95%) and related compounds (5%), DDVP, Delnav® (a mixture of 2,3-p-dioxanedithiol S,S-bis (O,O-diethyl phosphorodithioate) (70%) and related compounds), Dibrom® (1,2-dibromo-2,2-dichloroethyl dimethyl phosphate), dicapthon, dimethoate, Dowco 105 (O-4-tert-butyl-2-chlorophenyl O-methyl ethylphosphoramidothioate), Dowco 109 (O-4-tert-butyl-2-chlorophenyl O-methyl methylphosphoramidothioate), Isolan® (l-isopropyl-3-methyl-5-pyrazolyl dimethylcarbamate), Kepone® (decachlorooctahydro-l ,3,4-metheno-2H-cyclobuta[cd]pentalen-2-one), Perthane® (a mixture of diethyl diphenyl dichloroethane (95%) and related reaction products (5%)), phosphamidon, Pyrolan® (3-methyl-l-phenyl-5-pyrazolyl dimethylcarbamate), ronnel, Ruelene® (O-4-tert-butyl-2-chlorophenyl O-methyl methylphosphoramidate), Sevin® (l-naphthyl N-methylcarbamate), and Bacillus thuringiensis var. thuringiensis Berliner. The two muscid species were in most instances more tolerant of the insecticide-containing manure than either the sarcophagid or calliphorid. Several organic phosphate insecticides (American Cyanamid 12008, Bayer 22408, and dimethoate) were highly toxic to the larvae of all four species at levels in the feed ranging between 40 and 80 p.p.m. The carbamate insecticides included in the feed had no apparent effect on larval mortality while the two chlorinated hydrocarbon insecticides, Kepone and Perthane, exhibited but slight toxicity. The bacillus appeared to have limited usefulness for general fly control when administered in the feed to chickens.

Field Tests for the Control of Certain Alfalfa Insect Pests in New York

Field trials were made from 1958 to 1961 for the control of certain forage insect pests on alfalfa. The pea aphid, Macrosiphum pisi (Harris), was effectively controlled by most organic phosphate insecticides, some at relatively low levels. A number of insecticides gave good control of the potato leafhopper, Empoasca fabae (Harris), 3 days after application, but only methoxychlor and dimethoate were effective after 7 days. Triathlon® ( O,O -diethyl S-p- chlorophenylthiomethyl phosphorodithioate), Guthion® ( O,O -dimethyl S -(4-oxo-1,2,3-benzotriazin-3-(4 H )-ylmethyl) phosphorodithioate) and dimethoate at 1.0 pound and heptachlor, endrin, lindane and parathion at 0.25 pound per acre showed good control of various grasshopper species even at 14 days after treatment. Control of adults of the meadow spittlebug, Philaenus spumarius (L.), was obtained with numerous materials, the best of which were endrin, lindane, and Phosdrin® (a mixture of the alpha isomer of 2-carbomethoxy-I-methyl vinyl dimethyl phosphate (not less than 60%) and related compounds (not more than 40%)) at 0.25 pound, and methoxychlor and Guthion at 1.0 pound per acre. The phytotoxic nature of some of the organic phosphate materials, especially Guthion, to alfalfa plants will undoubtedly limit their use for forage insect control.

Boll Weevil Resistance to Several Chlorinated Hydrocarbon Insecticides in Georgia1

Studies on boll weevil ( Anthonomus grandis Boheman) resistance to the chlorinated hydrocarbon insecticides were conducted in the laboratory on weevils collected from 16 counties in Georgia. It was found that resistance to endrin was widespread in the State; only those weevils from the extreme northern counties were highly susceptible. Resistance to BHC and toxaphene was established. There was some indication of reversion to susceptibility to endrin from 1959 to 1960; however, little or no difference was found in the susceptibility of weevils following a change from field applications of chlorinated hydrocarbon to organic phosphate insecticides during 1961. Two years’ results showed field-collected weevils of unknown age to be 50 to 210 times harder to kill than 2-day-old square-reared weevils.

Effects of Chemicals on European Corn Borer Eggs1

The toxic effects of chemicals on the eggs of the European corn borer (Ostrinia nubilalis ((Hubner)) (Lepidoptera: Pyralidae) were studied. The organic-phosphate insecticides Diazinon® ( O,O- diethyl O -(2-isopropyl-4-methyl-6-pyrimidinyl) phosphorothioate), Dibrom® (1,2-dibromo-2,2-dichloroethyl dimethyl phosphate), Dylox® ( O,O -dimethyl 2,2,2-trichloro-1-hydroxyethyl phosphonate), ethion, Guthion® ( O,O -dimethyl S-(4-oxo-1,2,3 -benzotriazin-3-( 4H)-ylmethyl) phosphorodithioate), parathion, Phosdrin® (a mixture of the alpha isomer of 2-carbomethoxy-1-methylvinyl dimethyl phosphate (not less than (60%) and related compounds (not more than 40%)), and oil, when used at various rates were found to affect hatching of the eggs under laboratory conditions. When Diazinon, Dibrom, and Guthion were later used alone and in various combinations with DDT, Sevin® (1-naphthyl N -methylcarbamate) and Thiodan® (6,7,8,9,10,10-hexachloro-1 , 5,5a , 6,9, 9a-hexahydro-6, 9-methano-2, 4,3-benzodioxathiepin-3-oxide) on green peppers in the field, DDT, Guthion, and Sevin significantly reduced the corn borer infestation.

The oximes and organophosphate poisoning.

Since the insects began fighting back in 1947,1the war against them has demanded an increasingly diversified armamentarium, and the organic phosphate insecticides have played an important part in the battle. Unfortunately, this group of compounds, an outgrowth of wartime investigation of the chemically related nerve gases, are poisonous to man as well as to insects. For toxicologic purposes, they may be roughly divided into the highly toxic group, exemplified by parathion (O,O-diethyl-O-p-nitrophenyl thiophosphate) and TEPP (tetraethyl pyrophosphate), and those with less toxicity, such as malathion (O,O-dimethyl dithiophosphate of diethyl mercaptosuccinate). The former group is used primarily for agricultural insect control, whereas the latter compound has been approved for household use as well. The incidence of human poisoning by organic phosphorus insecticides appears to be increasing in frequency. In 1957 in California3there were 229 cases of occupational disease ascribed to organic phosphate insecticides, including one

Chemical Control of Hylemya brassicae in the Pacific Northwest1

Strains of cabbage maggot (Hylemya brassicae (Bouché)) highly resistant to chlorinated hydrocarbon and organic phosphate insecticides appeared in certain areas of the Pacific Northwest. Thirty-three compounds were tested as granules or drenches applied at planting time with cruciferous crops. All were ineffective except Zinophos (O,O-diethyl O-2-pyrazinyl phosphorothioate) which gave outstanding control. LD-50 tests demonstrated that the adults were highly resistant to chlorinated hydrocarbons but still susceptible to organic phosphates. A drench of Zinophos or Guthion® ( O,O-dimethyl S.(4-oxo-1,2,3- benzotrazin-3-(4H)-ylmethyl) phosphorodithoate) applied to transplants of cauliflower or cabbage provided excellent control against cabbage maggot attacks.

New concepts and future trends in toxicology.

Abstract New concepts and procedures derived from related fields of biochemistry, pharmacology, immunochemistry, and genetics, are now at the disposal of the industrial toxicologist to aid in the solution of problems in two broad areas of investigation, (1) early indicators of response to toxic agents, (2) mechanisms of toxic stress. Shown here are many ways of using body metabolites, tissue enzymes, alone and in combination, and tissue metals for the detection of early responses to toxic agents while the responses are still reversible. Immunochemical changes not heretofore recognized are now shown to be often a response to inhaled chemicals. Highlighted are mechanisms of action of CCL4, oxidant gases, radiomimetic chemicals, organic phosphate insecticides and other substances of industrial interest.

Effect of Various Insecticide Treatments on Populations of the Green Peach Aphid on Peppers in Southern California1

Various insecticides were evaluated for effectiveness against populations of the green peach aphid, Myzus persicae (Sulz.), on peppers during 1959-60. Most organic phosphate insecticides were relatively ineffective or caused a resurgence in aphid numbers after a fair initial control. Thiodan® (6,7,8,9,10,10-hexaehloro-1, 5,5a,6,9,9a-hexahydro-6, 9-methano-2,4,3-benzodioxathiepin 3-oxide) as a dust or spray, Bayer 30911 (methyl- O -methyl O -2,4-diehlorophenyl phosphonothioate) as a dust, and dimethoate, phosphamidon, and General Chemical 4072 (diethyl-1-(2,4-dichlorophenyl)-2-chlorovinyl phosphate) as sprays appeared to be highly effective against the aphid and reduced populations to low levels for periods ranging from 4 to 20 days.

Control of the Vetch Bruchid, Bruchus brachialis, in Oregon1

Insecticides were evaluated in Oregon for control of the vetch bruchid, Bruchus brachialis Fahr., in hairy vetch seed production in an attempt to reduce the possibility of a chemical residue on the small-grain companion crop normally seeded with vetch. The following toxicants selected and their control performances compared with the standard DDT recommendation: methoxychlor, malathion, Guthion® ( O,O -dimethyl S -(4-oxo-1,2,3-benzotriuzin-3-(4 H )-ylmethyl)phosphorodithioate), and Dibrom® (1,2-dibromo-2,2-dichloroethyl dimethyl phosphate) plus Volck® Supreme Oil. All treatments reduced vetch bruchid populations, and seed collected from treated plots germinated in excess of 90%. In addition, the populations of the pea aphid ( Macrosiphum pisi (Harris)) were reduced in those plots treated with an organic phosphate insecticide.