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Wastewater-based epidemiology is an innovative approach to estimate a population's intentional and unintentional consumption of chemicals based on biomarker assays found in wastewater. This method can provide real-time objective information on the xenobiotics to which a population is directly or indirectly exposed. This approach has already been used to assess the population exposure to four classes of pesticides: organochlorines (chlordecone), triazines, organophosphates, and pyrethroids. This review aims to obtain the data (excretion rates) and characteristics (pesticide and metabolites stability, including in-sewer one) for other pesticides to broaden the scope of this new method. Excretion rates and stability descriptions for 14 pesticides, namely 2,4-D, aldrin, carbaryl, chlorobenzilate, dieldrin, diquat, ethion, glufosinate, glyphosate, folpet, malathion, parathion, penconazole, and tebuconazole, will be discussed in a practical framework.

In multiresidue analysis, as the complexity of matrix increases, matrix co-extractives might co-elute and interfere with the detection of target analytes, and thereby result in false positives and erroneous quantifications. This paper aims to evaluate the combination of enhanced mass resolution and concurrent selectivity and sensitivity in analyzing a complex mixture of 341 pesticides in grape, orange, tomato, okra and spinach by gas chromatography triple quadrupole mass spectrometry (GC-MS/MS). Timed-selective reaction monitoring (t-SRM) was found advantageous over segment SRM in terms of ease of method optimization and sensitivity. The optimized t-SRM method was used to test the applicability of ultra-SRM (USRM) in filtering out co-eluting interfering matrix compounds. False detections of benfluralin, dimethoate, etc. could be avoided when mass resolution was increased from 0.7 to 0.4 and 0.2Da (full width at half maximum). Similar observations were noted for chlorobenzilate, spiromesifen, tebuconazole, etc., in grape; omethoate, bendiocarb, monocrotophos, etc. in orange; omethoate, dimethoate, ethoxyquin, atrazine, etc., in tomato; and dichlobenil, omethoate, propoxur, monocrotophos, etc., in okra. The analysis at higher mass resolution could significantly minimize matrix effects (ME), e.g., 34% at 0.7Da for spiroxamine in grape to 0.6% (0.4Da) and -44% (0.7Da) for dichlorvos in okra to 8.8% (0.1Da). A feature called "quantitation enhanced data-dependent (QED) scan feature" was found effective in targeted screening to confirm the detection of atrazine, azoxystrobin, λ-cyhalothrin, etc. at trace quantities in incurred samples and avoid false detection of chlorpyrifos.

Three diphenylcarbinol acaricides (dicofol, chlorobenzilate, and bromopropylate) and three structurally related diphenylethane insecticides (p,p′-DDT, o,p′-DDT, and methoxychlor) were evaluated as inhibitors of octopamine-stimulated adenylate cyclase activity in membrane preparations from whole homogenates of two-spotted mites (Tetranychus urticae Koch). In survey experiments, a high concentration (100 μM) of each of the three diphenylcarbinols produced complete or almost complete inhibition of the octopamine-stimulated component of adenylate cyclase activity, whereas the three diphenylethanes had no significant effect when assayed at the same concentration. Dicofol, chlorobenzilate, and bromopropylate each gave biphasic concentration-effect curves for the inhibition of octopamine-stimulated adenylate cyclase activity having a sensitive component of inhibition detectable between 0.01 and 0.1 μM, a plateau at approximately 20 to 30% inhibition in the concentration range of 0.1 to 1 μM, and a less sensitive component of inhibition evident between 1 and 100 μM. Concentrations of dicofol that produced complete inhibition of octopamine-stimulated adenylate cyclase activity had no effect on forskolin-stimulated adenylate cyclase activity. Membrane preparations isolated from a strain of mites exhibiting resistance to diphenylcarbinols and cross-resistance to amitraz showed unaltered sensitivity to amitraz as a stimulator of adenylate cyclase activity and to dicofol as an inhibitor of octopamine-stimulated adenylate cyclase activity. These results identify a novel action of diphenylcarbinol acaricides that does not extend to structurally related diphenylethane insecticides and suggest that the octopamine receptor-adenylate cyclase signal transduction pathway may be an important target site for diphenylcarbinols.

Cross-resistance of dicofol-resistant Tetranychus urticae Koch to 21 pesticides was evaluated. Initial investigations used field-collected dicofol-resistant and susceptible colonies. Near-isogenic lines, constructed by a series of backcrosses, were used to confirm or reject determinations of cross-resistance derived from evaluations of field-collected colonies. Dicofol-resistant T. urticae showed strong positive cross-resistance to amitraz, bromopropylate, and chlorobenzilate. Moderate negative cross-resistance to ward chlorpyrifos was observed. These results suggest that amitraz, bromopropylate, and chlorobenzilate should not be used in alternation with dicofol in a resistance management program designed to exploit the instability of dicofol resistance. The uptake and distribution of (14C)-dicofol was investigated in near-isogenic lines of susceptible and resistant mites. No difference in the uptake of radiolabel was observed between strains, suggesting that decreased penetration is not a major mechanism of dicofol resistance. In vivo metabolism studies revealed greater production of water soluble metabolites and lower levels of internal dicofol in the resistant strain compared with the susceptible. Therefore, the major mechanism of resistance to dicofol appears to be increased metabolic detoxification.

Twenty-four-hour urine samples were examined for 4,4′-dichlorobenzilic acid (DBA) pre-, during and post-exposure of dicofol applicators and mixer-loaders. Pre-exposure DBA excretion rates were not zero, since chlorobenzilate, a compound also yielding DBA as a urinary metabolite, had been used previously by the workers. Among workers, mean daily DBA excretion rates during the exposure period ranged from 19 to 42 μ g/day. Ninety-eight percent of this variation was explained by differences in estimated dicofol deposits onto their skin. Only (0.25 ± 0.02)% of the estimated dermal deposit appeared as urinary DBA. Post-exposure urinary DBA declined with a half-life of 7 ± 4 days.

In the modern era of industrialization, due to increase in the developmental activities, water is being polluted. It is essential to monitor and prevent the pollution load in drinking water as it has a direct link to human health. The objective of this study was to determine physico-chemical characteristics, bacterial contamination and pesticides in tap water samples collected from various selected sites of Noida City. Tap water samples were assessed for physico-chemical parameters like; pH, Dissolved Oxygen (DO), Total Dissolved Solids (TDS), Total Hardness, Alkalinity, Fluoride (F), Nitrate (NO3–3) and Sulfate (SO4–2). The water samples were also analyzed for the presence of fecal bacteria namely: Escherichia coli (E.coli), Salmonella, Pseudomonas aeruginosa, Staphylococcus aureus and total coliform bacteria present in tap water. Pesticides namely: Chlorobenzilate, Hexachlorobenzene, Benzenether, pp-DDT, op-DDT, pp-DDE, pp-DDD, alpha-HCH, Beta-HCH, Lindane, Vinclozolin, Conumaphos, Malathion, Phosalone, Cyfluthrin, Cypermethrin, Deltamethrin, Permethrin, Fenvalerate, Fluvalinate, Cyhalothrin, Carbofurn, Propoxeur, Carbaryl, Cymiazol, Amitraz, Bromprophylate, Chinomethionate were also detected.

Chlorobenzilate residues were determined on citrus foliage, fruit, and soil surfaces. Residue half-lives varied from 4 to 21 days depending on extraction method and time of the year. Increasing the application rate resulted in a proportional increase in residues. The standard “dislodgeable” method recovered less surface residues than did a methanol recovery. These data are discussed in relation to protecting harvesters from pesticides.

The toxicity of 15 citricultural pesticides to a San Joaquin Valley, California strain of Euseius hibisci (Chant) were evaluated in laboratory bioassays by use of the leaf disc-dip technique. Compounds of low toxicity were parathion, carbaryl, sabadilla, and fenbutatin-oxide. Malathion, methidathion, and propargite were moderately toxic to E. hibisci. Compounds highly toxic to this predatory phytoseiid were methomyl, acephate, cyhexatin, dimethoate, dicofol, chlorpyrifos, oxythioquinox, and chlorobenzilate. Adult females were highly sensitive to methomylleaf residues. A majority of females moved off into the water barrier soon after their placement on the treated surface at levels as low as 0.94 g (AI)/100 liters. The potential for augmentation and conservation of the strain for the biological control of spider mites and citrus thrips in San Joaquin Valley citrus integrated pest management programs are suggested.

Laboratory bioassays were conducted on leaf discs to determine the impact of 20 pesticides on two strains of Euseius hibisci (Chant) colonized from citrus. The herbicides and fungicides tested were modestly lethal to both E. hibisci strains. However, paraquat, glyphosate, and dikar expressed toxicity to E. hibisci . Laboratory bioassays showed that E. hibisci ’s tolerance to chlorobenzilate was moderate for both strains as compared with dicofol. Azinphosmethyl, methidathion, and sulfur exhibited moderate acaricidal activity to the RH strain as compared with our standard LAB strain. E. hibisci was very susceptible to methomyl. Dimethoate was the only OP which caused high mortality in both strains. Although the resistance level of the RH strain to dimethoate was considerably lower than the recommended field dosage, it was 22-fold that of the LAB strain.

Impacts of field-weathered residues of nine acaricides (amitraz, avermectin + oil, chlorobenzilate + oil, cyhexatin, dicofol, fenbutatin-oxide, oil, oxythioquinox, and propargite) on survival of selected beneficial arthropods of citrus ( Aphytis melinus DeBach, Cryptolaemus montrouzieri Mulsant, and Euseius stipulatus Athias-Henriot) were evaluated in two field trials. Concurrent with bioassays, foliar residue analyses were performed and were correlated with mortality. With the exception of moderate (causing amitraz > oxythioquinox > cyhexatin > chlorobenzilate + oil > propargite (least persistently toxic).

A Rebuttable Presumption Against Registration (RPAR) was issued for chlorobenzilate (CB) in May, 1976 (BOYD 1978). In June, 1978 a Notice of Determination was published by the U.S. Environmental Protection Agency because the presumptive cancer r isk associated with exposure to the acaricide had not been adequately negated by assessment and research. By February, 1979 a Notice of Intent to cancel a l l non-citrus uses of CB was issued. Use of chlorobenzilate was thereby l imited to c i t rus crops grown in Texas, Cal i fornia and Florida. The conditions for reg is t ra t ion of CB were also made more str ingent : ( I ) i t was rec lass i f ied as a rest r ic ted use pest icide, (2) a new label indicat ing s t r i c t e r use conditions was required and (3) u t i l i za t i on of more effect ive protective clothing and equipment were recommended.

Laboratory cultures of the granary weevil, Sitophilus granarius (L.), and the rice weevil, Sitophilus oryza (L.), were invaded by mites of two genera, Typhlodromus and Acaropsis. Several acaricides were tested for the purpose of eliminating mites from rearing and testing areas of the laboratory without causing undue harm to insects in cultures. Methods are described for the use of Kelthane and Chlorobenzilate to eradicate mites in rearing and testing areas of a stored-product insects laboratory, the use of Kelthane for the control of mites in weevil cultures, and for the prevention of new infestations.

High-gallonage sprays were applied to greenhouse roses heavily infested with two-spotted spider mites ( Tetranychlls telarius (L.)) to determine the extent of resistance and what groups of compounds might afford practical control. The results indicate that resistance has developed to most of the materials previously used for mite control; these include Aramite® (2-( p-tert -butylphenoxy) isopropy! 2-chloroethyl-sulphite), chlorobenzilate, tetradifon, tepp, malathion, and schradan. There is also evidence that cross resistance has developed to numerous pesticides, for many that have not previously been used were nevertheless ineffective. It is apparent from this study that compounds unrelated to previously used acaricides are effective against these resistant mites. Binapacryl, Eradex® (2,3-quinoxalinedithiol cyclic trithiocarbonate), and Bayer 36205 (6-methyl-2,3-quinoxalinedithiol cyclic carbonate) can be placed in this category but cannot be used at effective dosages because of phytotoxicity on roses. Pentac (bis(pentachloro-2,4-cyclopentadien-5-yl), and Bidrin® (3-hydroxy- -N,N -dimethyl- cis -croton-amide dimethyl phosphate) represent two dissimilar materials that show promise for control of resistant mites on roses. Pentac, with its low mammalian toxicity and lack of phytotoxicity, has already proven to be a highly practical and effective control.

A strain of the Pacific spider mite, Tetranychus pacificus McGregor, which had developed resistance in the field to demeton treatments was subjected in the laboratory to parathion selection pressure at the 70% mortality level through 10 selections without further change in the degree of cross resistance to parathion. Starting with a susceptible strain, six to nine such selections with parathion and ethion resulted in high degrees of resistance to both accuracies. Similar selection procedures using Aramite® (2-( p-tert -butylphenoxy) isopropyl 2-chloroethyl sulfite) resulted in a 10-fold increase in resistance after 15 selections; but using Chlorobenzilate® (ethyl 4,4′-dichlorobenzilate or Kelthane® (1, 1-bis( p -chlorophenyl)-2,2,2-trichloroethanol) resulted in no change in susceptibility after 23 or 22 selections, respectively. In cross resistance evaluations parathion- and ethion-resistant strains were cross resistant to the other organ phosphorus accuracies evaluated but not to the specific acaricides. Aramite-, Chlorobenzilate-, and Kelthane-selected strains were cross resistant to some organophosphorus compounds but not to other specific acaricides. This response is contrasted with the response of house flies ( Musca domestica L.) to selection pressure with insecticides.

Two species of predaceous typhlodromid mites Typhlodromus fallacie (Garman) and Phytoseiulus persimilis A.-H. are important natural biological agents in the suppression of spider mite populations. A study was made to determine the possibility of developing an integrated biological-chemical control program by selecting pesticides least toxic to the typhlodromids and yet effective as control for diseases and insects on the host crops. Of 31 pesticides tested, the predaceous mites tolerated residues of 12 chemicals that included the insecticides aldrin, dieldrin and endrin; the acaricides Aramitc® (2-( p-tert -butylphenoxy) isopropyl 2-chloroethyl sulfite), chlorobenzilate, Kelthane® (1,1-bis( p -chlorophenyl)-2,2,2-trichloroethanol), tetradifon, and ovex; and the fungicides captan, maneb, Folpet® ( N -(trichloromethylthio) phthalimide), and zineb. The results of present studies encourage further investigations to evaluate the control of spider mite populations using predator mite releases alone or in combination with a selective spray program.

Chlorobenzilate (ethyl 4,4′-dichlorobenzilate), chloropropylate (isopropyl 4,4′-dichlorobenzilate), and bromopropylate (isopropyl 4,4′-dibromobenzilate) were metabolized by rat liver preparations, with the microsomal and the nuclear supernatant fractions being most active. The limiting reaction was cleavage of the ester linkage by carboxylesterases, which showed greater activity for the ethyl ester (chlorobenzilate) than for the isopropyl ester (chloropropylate and bromopropylate). This initial reaction was blocked by the organophosphate DFP (diisopropyl phosphorofluoridate). SKF-525A enhanced to some extent the degradation of chlorobenzilate by the mitochondrial and possibly the microsomal fractions. p-Chlorobenzoic acid from chlorobenzilate and chloropropylate and p-bromobenzoic acid from bromopropylate were the identified end products of acaricide metabolism by the hepatic enzymes.

Little work has been reported on the control of eriophyid mites with synthetic organic acaricides, and virtually none on the wheat curl mite, Aceria tulipae (Keif.). Rolling of the leaves caused by this species and the tendency for some mites to occur deep in the leaf sheaths between two surfaces protects them from sprays and suggested the translocation of systemic insecticides as the most promising means of control. Spraying with 30 different insecticides in greenhouse and field in the spring resulted in none that gave both high initial and long residual control. Eighty to 90% control was obtained at 2 to 3 days in the field with several insecticides but none exceeded 90% control. Best control at 5 weeks following spraying of young wheat in the fall was obtained with endrin in light mineral seal oil. After determining the maximum concentration of each systemic toxicant that was not highly detrimental to germination, three concentrations of each toxicant were tested. Retardation and/or reduction in germination resulted from the use of all seed treatments, although not above the 5% confidence limit in most cases when the toxicant did not exceed 0.125 pound per bushel. Impregnation of the toxicant in 4 pounds of Carhowax-6000 per bushel of seed, gave better control than soil drenches. Am. Cyanamid 12009 (95% control) and 12008 (85% control) at an average from 0.125 to 0.5 pound of toxicant in 4 pounds of Carbowax per bushel of seed, gave the best overall results at the end of 1 week. When these toxicants were impregnated in attac1ay at 1.0 pound toxicant per bushel, 89 and 74% control, respectively, was obtained at 1 week and 98 and 97%, respectively, at the end of 5 weeks. In field studies on plantings of fall-treated seed, best results, using Am. Cyanamid 12008 (89% control) and 12009 (72% control), were recorded at 5 weeks when the toxicant was used without being impregnated in granules. Mites were present in all cases when counts were made 10 weeks following planting as well as during the following spring. In no instance was control of wheat-streak mosaic obtained from seed treatments in 1954 when viruliferous mites were constantly introduced in large numbers onto the young wheat plants.

Studies of populations of the citrus bud mite, Aceria sheldoni (Ewing). over a period of 2 to 5 years in treated and untreated plots in four southern California lemon orchards are reported. In untreated plots a rapid increase in infestations in lemon buds started in Mayor June and peaked in August or September. In some years high populations were maintained throughout the fall and winter; in other years populations gradually decreased during the winter. In either case, populations fell to an annual low during April and May. These general population trends were correlated with seasonal climatic changes and plant growth cycles. Warm summer weather favorable for plant growth and also for mite dispersal resulted in rapid increase in infestation, whereas winter conditions appeared to reduce movement from one bud to another. Periods of low humidity during the winter or spring appeared to be major factors in the decline of infestation within the buds during this period. An unusually hot period in September 1955 resulted in a sharp decrease of infestation, especially in the orchard farthest from the coast. The summer population increase was about 1 month later under fruit buttons than in the buds. Populations under fruit buttons were higher than bud populations during most of the year. Applications of petroleum oil and of Aramite in both fall and spring were necessary for adequate control. Chlorobenzilate was most effective when applied between the first of June and the last of September, and a single application during this period kept mite populations low for a year.

Sixteen acaricidal compounds were compared for effectiveness in controlling the spider mite complex on cotton in the San Joaquin Valley of California. The complex consists of the two-spotted spider mite, Tetranychus urticae (Koch); the strawberry spider mite, T. atlanticus McGregor; and the Pacific spider mite, T. pacificus McGregor. The compounds were: Aramite® ( 2-(p-tert -butylphenoxy)-isopropyl 2-chloroethyl sulfite); binapacryl; chlorobenzilate; Chloropropylate® (isopropyl 4,4’-dichlorobenzilate); demeton; dicofol; methyl demeton; Morestan®(6-methyl-2,3-quinoxalinedithiol cyclic S,s -dithiocarbonate); Pentac® (bis(pentachloro-2,4-cyclopentadien-l-yl); sulfur; tetradifon; tetrasul; thioquinox; and Union Carbide compounds UC-19786 (2- sec -butyl-4,6-dinitriphenyl isotropy carbonate), UC-20047A (exo-5-chloro-6-oxo- endo -2-norbornane-carbonitrile O -(methylcarbamoy) oxime), and UC-21149 (2-methyl-2-(methythio) propionaldchyde O -(methylcarbamoy) oxime). Application was made with standard ground and aircraft equipment. Mites were counted directly on the infested leaves or by a sodium hypochlorite wash method which removed the mites from the leaves for counting. The effectiveness of demetion and methyl demeton appeared to be limited by organophosphate resistance in the particular mite populations under study. Foliar sprays of dicofol, tetradifon, chlorobenzilate, Aramite, and Morestan were highly effective for up to 6 weeks after spraying, provided coverage of the plants was good. The other materials caused moderate mite mortality, but were not sufficiently effective.

Several chlorinated hydrocarbon pesticides, considered to be specific acaricides, were shown to be in vitro inhibitors of the ATPase enzyme system from blue gill fish brain homogenates. Mitochondrial (oligomycin-sensitive) Mg2+ATPase from fish brain was inhibited by each chlorinated bridged biphenyl compound (ovex, chlorberside, chlorobenzilate, 4,4′-dichloro-a-methylbenzhydrol, and 2,4-dichlorophenyl benzenesulfonate). Moreover, these compounds were relatively ineffective on Na+-K+ATPase and the oligomycin-insensitive Mg2+ATPase. In contrast, decachlorobi-2, 4-cyclopentadien-1-yl, a bicyclic pentadienyl compound, inhibited Na+-K+ATPase and oligomycin-insensitive Mg2+ATPase. An alkyl aryl sulfite, 2-(p-tert-butyl-phenoxy)-1-methylethyl 2-chloroethyl sulfite, was relatively ineffective on the ATPase enzyme system. An in vivo correlation, based upon behavior of mites, was shown between the effect on the ATPase system and acaricidal activity.

The mites Phyllocoptruta oleivora (Ashmead) and Aculops pelekassi (Keifer) were dipped in plastic-lined cartons and in glass beakers containing 3 concentrations of 5 insecticides (cthion, carbophenothion, chlorobenzilate, dicofol, and dioxathion). Mortality was always significantly lower in the plastic-lined container. Plastic liners probably affect results obtained with other compounds.

In tests of acaricides for the control of a Tyroglyphid mite, Aleuroglyphus ovatus (Troupeau), infesting cultures of the oriental rat flea, Xenopsylla cheopis (Roths.), in jars provided with linen covers and containing Purina dog food in sand as the rearing medium, Tedion and Kelthane proved ineffective, but light infestations (100 cc. of medium inoculated with 500 mites) were satisfactorily controlled by chlorobenzilate at 0·2 p.p.m. in the rearing medium or as a 0·05 per cent, solution in acetone painted on to the inner wall of the jar and used to soak the linen cover for three seconds. Heavy infestations (100 cc. medium inoculated with 2,000–3,000 mites) were controlled by chlorobenzilate at 20 p.p.m. in the medium or as a 0·5 per cent, solution applied to both the linen cover and the inner rim of the jar; a combination of both treatments (using 2 p.p.m. and a 0·5 per cent, solution) gave adequate control for 30 days.The flea larvae were unaffected by 2 p.p.m. chlorobenzilate in the rearing medium; 20 p.p.m. killed larvae, but not adults. Neither stage was affected by treating the linen cover and inner rim of the breeding jar with a 0·5 per cent, solution of chlorobenzilate.Measures are recommended for maintaining flea cultures free from mites, based on these experimental results and on a year's practice.

Rhodotorula gracilis metabolizes Chlorobenzilate (ethyl 4,4′-dichlorobenzilate) and Chloropropylate (isopropyl 4,4′-dichlorobenzilate) to several metabolites in a basal medium supplemented by sucrose and by several intermediates of the citric acid cycle. Three identified metabolites resulting from the degradation of either acaricide, were 4,4′-dichlorobenzilic acid, 4,4′-dichlorobenzophenone, and carbon dioxide. Chlorobenzilate, i.e., ethyl ester of 4,4′-dichlorobenzilic acid, was more easily hydrolyzed than Chloropropylate, i.e., isopropyl ester of this acid, so that larger amounts of carbon dioxide and 4,4′-dichlorobenzophenone were obtained from Chlorobenzilate degradation. Regardless of acaricides used, longer incubation caused a higher accumulation of 4,4′-dichlorobenzophenone. The probable steps of the degradation pathway are: Chlorobenzilate (or Chloropropylate) → 4,4′-dichlorobenzilic acid → 4,4′-dichlorobenzophenone plus carbon dioxide. It appears that the decarboxylation of 4,4′-dichlorobenzilic acid to 4,4′-dichlorobenzophenone was hindered by α-ketoglutarate and enhanced by succinate.

Field trials of acaricides were made in 1963 and 1964 for the control of the European red mite, Panonychus ulmi (Koch), on apples. The materials were applied during the summer in 2 successive sprays from 7 to 10 days apart. Of the currently labeled acaricides, the best control was given by Kelthane® (1,1-bis(p-chlorophenyl)-2,2,2- trichloroethanol), Morestan® (6-methyl-2,3-quinoxalinedithiol cyclic carbonate), tetradifon, demeton, and Guthion ® (O,O -dimethyl S-(4-oxo-1,2,3-benzotriazin-3 (4H) - ylmethyl) phosphorodithioate). Other very effective compounds were binapacryl, dinocap, chlorobenzilate, and phosphamidon. Of the experimental materials Animert® (p-chlorophenyl 2,4,5-trichlorophenyl sulfide), Bidrin® (3-hydroxy- N,N -dimethyl- cis -croton-amide dimethyl phosphate), dimethoate, Bayer 37344 (4- (methylthio) -3,5-xylyl methylcarbamate), Union Carbide 20047A (5-chloro-6-oxo- endo - 2 norbornanecarbonitrile O -(methylcarbamoyl)oxime), and Hooker HRS 1654 (decachlorobi-2,4-cyclopentadien-1-yl) were outstanding. No phytotoxicity was prominent with any of the treatments. Under Ohio conditions no real differences were noted with wettable powder and emulsifiable concentrate formulations of the various acaricides.

Soil treatments of various insecticides were made on Turkey ranges to determine their effectiveness against the chigger Neoschngastia americana (Hirst). Carbaryl, chlorobenzilate, Compound 4072 (2-chloro-1-(2, 4-dichlorophenyl) vinyl diethyl phosphate), coumaphos, dichlorvos, dioxathion, Imidan® ( O, O -dimethyl S -phthalimidomethyl phosphorodithioate), malathion, methoxychlor, ovex, ronnel, Shell SD-8447 (2-(chloro-1-(2,4,5-trichlorophenyl) vinyl dimethyl phosphate), sulfur, and toxaphene were shown to be ineffective. Diazinon, ethion, Geigy GS-13005 ( O, O -dimethyl phosphorodithioate S -ester with 4-(mercaptomethyl)-2-methoxy-∆2-1,3,4-thiadiazolin-5-one), and lindane need further evaluation. Dursban® ( O, O -diethyl O -3,5,6-trichloro-2-pyridyl phosphorothioate) was selected as the most promising and was evaluated in larger tests.

Four parasites of the citrus mealybug, Planococcus citri (Risso), which included Pauridia peregrina Timberlake, Leptomastix dactylopii Howard, Leptomastidea abnormis (Girault), and Anagyrus pseudococci (Girault) and 2 predators Cryptolaemus montrouzieri Mulsant and Sympherobius barberi (Banks) were exposed for 24 h to pesticide residues on leaves of commercially treated citrus in Texas. L. abnormis and P. peregrina were the most susceptible species tested while C. montrouzieri was the most tolerant. Pesticides tested included methidathion, carbophenothion, azinphosmethyl, chlorobenzilate, ethion, and citrus oil. The toxic residual activity of azinphosmethyl-oil combination gave the highest natural enemy mortality over a 35-day posttreatment period, while a chlorobenzilate-oil combination resulted in the lowest mortality.

The compatibility of six citrus pesticides with a field population of Euseius stipulatus (Athias-Henroit) was investigated. The ability of E. stipulatus to feed on pollen allowed observation of mortality due to the pesticides alone without the interference of predator starvation caused by prey mortality. All pesticides tested except chlorobenzilate significantly reduced predator population densities beyond 66 days postspray. When population reductions were analyzed as cumulative predator mite days, all materials again caused significant reductions in potential predation by E. stipulatus , even at 83 days postspray. The effects of predator reductions in relation to pest management are discussed.

Experiments were conducted on the chemical control of a field population of Tetranychus telarius (L.) on cotton, suspected of being resistant to organophosphorous miticides. Varying degrees of resistance by this spider mite were exhibited to demeton, ethion, carbophenothion, Bidrin® (3 - hydroxy - N, N - dimethyl- cis -croton-amide dimethyl phosphate), and phorate. Other types of miticides such as Aramite® (2 ( p-tert -butylphenoxy) isopropyl-2- chloroethyl sulfite), chlorobenzilate, and Kelthane® (1,1- bis ( p -chlorophenyl) -2,2,2-trichloroethanol) were found to have retained their effectiveness against this species. However, these materials were not so effective as the organophosphorous miticides were prior to the development of a resistant strain. Furthermore, field surveys revealed that difficulties in controlling either resistant or susceptible mites were induced largely by the failure to utilize cultural and natural controls. On the basis of field observations, control of T. atlanticus McGregor with organophosphorous acaricides was not so good as that obtained in previous years.

The effectiveness of registered and experimental materials was evaluated as to the ability to control the pear rust mite, Epitrimerus pyri (Nalepa). Materials chosen for testing were selected as to prior knowledge of their ability to give control of 1 or more of the “major pests” of pear. Timing of materials for effectiveness was evaluated in applications made at prebloom, early summer, and midsummer timings. The results indicated prebloom application more effective than foliar application. In all applications excellent initial kill of motile stages was obtained with the exception of Guthion,® ( O, O -dimethyl S -(4-oxo-1,2,3-benzotriazin-3 (4 H )-ylmethyl) phosphorodithioate), but residual control was quite variable.

Experiments to avoid the constant use of zineb (zinc ethylene-bis-dithiocarbamate) against citrus rust mite, Phyllocoptruta oleirora (Ashmead), by integrating 5.2 ounces of zineb per 100 gallons of spray, 2.0 ounces of Chlorohenzilate® (ethyl 4,4’-dichlorobenzilate) and 160.0 ounces of sulfur in spray programs were conducted on Valencia orange trees. Three sprays were used in each program: postbloom, midsummer and fall. Chlorobenzilate was a good substitute for zineb in postbloom sprays, but poor in the summer; sulfur was unsatisfactory in both postbloom and summer sprays; and Chlorobenzilate, zineb and sulfur were equal in the fall. The sequence of postbloom Chlorobenzilate, summer zineb and fall sulfur was a good substitute for three applications of zineb.

Brevipalpus phoenicis (Geijskes) (sometimes called the false spider mite), is worldwide in distribution. It has been reported from citrus in the United States (Florida and Texas), Mexico, Cuba, Trinidad, Argentina, Brazil, Venezuela, Aden, Ethiopia, Egypt, Spain, Syria, India, and the Philippines. With the exception of the citrus rust mite, Phyllocoptruta oleivora (Ashmead), this is the most frequently encountered mite in unsprayed or occasionally sprayed Florida citrus groves (Muma 1965). On citrus, it is often associated with B. californicus (Banks) and B. obovatus Donnadieu, but unlike them, it does not produce leprosis (Knorr 1968). B. phoenicis has been suspected, however, of causing swellings on citrus stems (“Brevipalpus gall”), dropping of leaves (“halo scab”), and foliar chlorosis (“phoenicis blotch”) (Knorr and Malaguti 1960, Knorr et al. 1960).

In laboratory tests, Angora goats infested with biting lice ( Bovicola spp.) were dipped in 13 insecticides. All but 0.1% and 0.25% chlorobenzilate and 0.1% carbaryl freed goats of lice. In field tests, 22 herds of goats infested with biting lice and goat sucking lice ( Linognathus stenopsis (Burmerister)) and 3 flocks of sheep infested with sheep biting lice ( Bovicola ovis (L.)) were sprayed with 11 insecticides. All except 0.5% methoxychlor controlled existing populations of motile lice. Biting lice were controlled from shearing to shearing on goats sprayed with 0.25% Ruelene® ( O -4- tert -butyl-2-chlorophenyl O -methyl methylphosphoramidate) and on sheep sprayed with 0.25% General Chemical 4072 (2-chloro-1(2,4-dichlorophenyl)vinyl diethyl phosphate) and 0.25% V-C 13 Nemacide® (0-2,4-dichlorophenyl O,O -diethyl phosphorothioate). Sucking lice were controlled from shearing to shearing on goats sprayed with 0.25% General Chemical 472 and 0.25% Relene.

The citrus bud mite, Aceria sheldoni (Ewing), is one of the most serious pests of lemons in the coastal areas of California. In 1941, Boyce & Korsmeier found that petroleum oil sprays were effective in control of this mite pest, and since that time these sprays have been largely relied on for control. In citrus culture, however, there are many situations in which it is inadvisable to apply petroleum oil sprays. Therefore, studies directed toward findng a substitute chemical control have been in progress at this station for several years.

Tests were performed with 9 acaricides in different dosages against the two-spotted spider mite, Tetranychus urticae Koch, a serious pest of brinjal in West Bengal. In general all the pesticides gave good results in knockdown and residual persistence for the test period. Tetradown (Tedion®) was somewhat slow in action but showed good residual effect. The acaricides from tile viewpoint of economics, can he arranged serially as follows: wettable sulfur, carbophenothion (Trithion®), elmental sulphur in colloidal form (Sulkol®), phosphamidon (Dimecron®), tetradifon, dimethoate (Rogor®), dicofol (Kelthanc®), lime sulfur, and chlorobenzilate (Akar®). Though wettable sulfur is the cheapest material for the control of mites alone, carbophenothion appears to be most economical, as it is effective against a wide range of pests associated with the mite.

From 1952 to 1968, several hundred insecticides were assayed in the laboratory (by topical applications to the thoracic mesonotum) for toxicity to the 3 species of tephritids found in Hawaii: oriental fruit flies, Dacus dorsalis Hendel; melon flies, D. cucurbitae Coquillett; and Mediterranean fruit flies, Ceratitis capitata (Wiedemann). The results with 73 insecticides are reported by computed dosemortality curves LD50 levels in eg toxicant/fly, the upper and lower limits at the 95% confidence level, and the slopes. Malathion was the standard for comparison. LD50’s were not established for chlorobenzilate, dicofol, Zinophos® O, O -diethyl O -pyrazinyl phosphorothioate), and tetradifon. At any dose tested, no LD50 against oriental fruit flies was established for carbaryl; no LD50 against the melon fly was established for DDT, methoxychlor, and Pyrazoxon® (diethyl 3-methylpyrazol-5-yl phosphate); and no LD50 against oriental fruit flies and melon flies was established for Terbeno® (polychlorinated terpene). Dimethoate and naled were generally the most toxic of the insecticides against all 3 species when they were applied in this manner.

As discussed by Gunther & Blinn (1955), there appear to be two principal types of residues on and in treated plant parts. When log residue or percentage of loss or retention of residue is plotted against days after application, a single straight line is obtained with most substrates. With citrus peel as the substrate, however, two intersecting straight lines are usually obtained. The single line represents the summation of degradation3 and persistence behavior, whereas the initial straight line of an intersecting pair is considered to represent degradation, and the line of subsequent behavior to represent the persistence phenomenon. Obviously, the two types of behavior overlap with citrus peel, but it is convenient for purposes of discussion to consider that degradation curves demonstrate graphically the sum of the processes usually classified as weathering, and that falling persistence curves undoubtedly demonstrate enzymatic or other alterations of the parent molecule within the plant part (Gunther & Blinn 1955).

Exposure of applicators and mixer-loaders to chlorobenzilate in Florida citrus groves was monitored on each person with dermalα-cellulose pads attached at 12 locations on the body and with personal air monitors worn by each subject. Urine samples were analyzed for the presence of chlorobenzilate metabolites. Applicators received about four times the dermal exposure of mixer-loaders but did not have significantly higher urinary metabolite levels. Respiratory exposure was uniformly low. Disposable coveralls reduced urinary metabolite excretion rates 24%. Disposable coveralls and hand protection covering the wrist afforded practical protection.

The interation of Rhizopus delemar C-lipase with 1, 1, 1-trichloro-2, 2-bis(4-chlorophenyl)ethane (DDT) and structurally related pesticides was studied. Binding assays and titration experiments revealed that the binding is distinctly cooperative and the 1 : 1 pesticide-lipase complex formation governs the ensuing complex formation. The chlorinated pesticides used here fall into three groups according to the mode of interaction with lipase. (1) DDT, 1, 1-dichloro-2, 2-bis(4-chlorophenyl)ethane (DDD) and 1, 1-dichloro-2, 2-bis(4-chlorophenyl)ethylene (DDE), the 1 : 1 pesticide-lipase complexes of which bind 8 further molecules of any pesticide used here to form 9 : 1 complexes with much higher activity. (2) Dimic and dichlorobenzophenone, the 1 : 1 pesticide-lipase complexes of which can bind 8 further molecules of the same pesticide without activation, but cannot bind any other pesticide. (3) Kelthane, chlorobenzilate and chloropropylate, which are non-competitive inhibitors of the intact lipase but behave as activators for 1 : 1 pesticide-lipase complexes of pesticides in group (1).The formation of the very tightly bound 9 : 1 DDT-lipase complex at pH 4.5 Chromatography on CM-Sephadex C25 gave results supporting the one-step formation of a 9 : 1 DDT-lipase complex from a 2 : 1 DDT-lipase complex.

The effect of various pesticides and derivatives on mitochondrial electron transport systems was assessed. DDT, DDE, TDE, Kelthane, chlorobenzilate, chloropropylate and Acarol were found to be inhibitory towards both heavy beef heart mitochondrial (HBHM) NADH-oxidase and succinoxidase enzyme systems. Dichlorobenzophenone andp-chlorophenol were less inhibitory towards the HBHM NADH-oxidase and did not inhibit the succinoxidase enzyme system. DDA did not inhibit either of the electron transport systems. Carbaryl was not inhibitory towards both HBHM oxidase systems, whereas its degradative product dihydroxynaphthalene was inhibitory at the same concentration. Furadan, Matacil, Baygon and Dimetilan were only slightly inhibitory towards the mitochondrial NADH-oxidase system and did not inhibit the succinoxidase system. Zectran was inhibitory towards the NADH-oxidase system and was not inhibitory towards the succinoxidase system. DDT, DDE and TDE, dihydroxynaphthalene and 1-naphthol inhibited the NADH-oxidase enzyme system on the substrate side of cytochrome c, whereas Kelthane inhibited on the oxygen side.

The photodecomposition of aqueous solutions of 2,2-bis (p-chlorophenyl) acetic acid (DDA) was slow in sunlight and rapid in the laboratory, producing p,p'-dichlorobenzophenone (DCB), p-chlorobenzaldehyde, p-chlorophenol, and several unidentified polar products. p,p'-Dichlorobenzilic acid, and p,p'-dichlorobenzhydrol gave rise to the same photoproducts, while bis-(p-chlorophenyl) methane (DDM) and chlorogenzilate were converted only to DCB. DCB and p-chlorogenzaldehyde proved to be resistant to photodegradation but gradually produced p-chlorobenzoic acid which, in turn, formed p-hydroxybenzoic and benzoic acids, probably the last environmentally detectable links in the long chain of DDT degradation to CO2 and water. High pressure liquid chromatography (HPLC) proved to be ideal for separating and quantitating the parent compounds and their photoproducts directly from the aqueous photolysates or from methanol solutions of the isolates and standards.

Anin vitro assay measuring inhibition of metabolic cooperation in Chinese hamster lung fibroblast cells (V79) was used to investigate the effects of DDT and five DDT analogs (dicofol, chlorobenzilate, bromopropylate, chloropropylate and fenarimol). These compounds were studied primarily because of the nongenotoxic but simultaneously carcinogenic properties of DDT and its analogs (chlorobenzilate and dicofol) and, secondly, to investigate how variations in the metabolic cooperation of hamster cells could be related to the chemical structure of the compounds. The results clearly demonstrate that all tested pesticides influenced the metabolic cooperation in a dose-dependent manner. The weak response of fenarimol suggests that sterical hindrance might influence the inhibition of metabolic cooperation.

The dissipation of acaricide chlorobenzilate in selected soil and river water samples was studied. Under incubation conditions at 25°C and 90% field capacity of moisture for 21 days, the residues of chlorobenzilate were 14 and 55% in Lukang silty clay loam and Pincheng clay, respectively. More than 80% of chlorobenzilate remained in the natural water (pH 7.2 and 7.3, respectively) and in the water adjusted to pH 5.0 when water samples collected from Green Lake and Wai-Shuang River near Taipei were treated with chlorobenzilate and then incubated for 34 days. But when the pH was adjusted to 9.0, only 60% was found in Green Lake water and 29% in Wai-Shuang River water. The dissipation of chlorobenzilate in the soil was fitted to first-order kinetics with half-lives of 5 to 36 days under various conditions in the laboratory experiments. No chlorobenzilate was detected in the leachate by a leaching experiment on the soil column for 18 days; most chlorobenzilate remained in the upper 3 cm of the column. According to assessment by the groundwater pollution-potential model (GWP), chlorobenzilate seemed to be safe in regard to groundwater contamination.

Seven compounds were evaluated for control of some spider mites on 3 ornamental plants in Louisiana. These were: Acaralate® (isopropyl 4,4’-dichlorobenzilate), GS-19851 (isopropyl 4,4’-dibromobenzilate), GS-13005 ( O, O- dimethyl phosphorodithioate S -ester with 4-(mercaptomethvl)-2-methoxy-∆2-1,3,4-thiadiazolin-5-one), Galecron® ( N’- (4-chloro-o-tolyl)- N, N -dimethylformamidine), Nissol® (2-f1uoro, N-methyl- N -I-naphthylacetamide) (may apply only to 25% EC), chlorobenzilate, and tetradifon. GS 13005 and GS-198.51 were most effective in controlling the southern red mite, Oligonychus ilicis (McGregor), on holly and azaleas and the two-spotted spider mite, Tetranychus urticae Koch, on roses. GS-13005 was most effective in controlling a green mite, Eotetranychus clitus (Pritchard & Baker), and GS-19851 ill controlling the privet mite, Brevipalpus obovatus Donnadieu, on azaleas. Other compounds gave a significant degree of control, but none were so effective as GS-13005 and G5-19851.

The effectiveness of early-season sprays against the European red mite ( Panonychus ulmi (Koch)) and of summer sprays against both this mite and two-spotted spider mite ( Tetranychus telarius (L.)) on apples was studied. An oil at the green-tip stage (March 26) or one to three applications from April 19 (bud-pink) to May 20 (second cover) of Tedion, Genite, Chlorbenside, demeton, Thimet, ovex (both the standard and an experimental (Dow M-928) formulation), Chipman R-6199, schradan, or p -chlorophenyl benzene sulfonate (Fenson) were effective for at least 60 days after petal fall. A dormant oil-dinitrocresol spray was less effective. Single applications of Kelthane, Hercules AC-528 ad Guthion early in July gave less than one mite per leaf, and of demeton, thimet, Trithion, Aramite, Chipman R-6199, Chlorobenzilate, and ethion (Nialate) less than four mites per leaf after 4 weeks. Ovex in both formulations was not effective so long as the other materials, but two applications of the standard formulation gave excellent control. None of the materials injured fruit or foliage.