Determination of residues of promecarb and its metabolite, 3-methyl-5-isopropylphenol,in cattle

A procedure is described for the colorimetric determination of promecarb as 3-methyl-5-isopropylphenol in tissues using 2,6-dichlorpbenzoquinone-4-chlorimine as the chromogen. Cattle were exposed to either 1, 3, 5 or 8 spray applications of a 0·2% promecarb emulsion at 3-day intervals or were fed promecarb at 2 ppm or 20 ppm daily in the diet for 20 days. All animals were slaughtered 30 h after final exposure. Of the animals in the spraying trial, residues in omental fat ranged from 0·9 ppm to 1·5 ppm promecarb and 0·4 ppm to 1·9 ppm 3-methyl-5-isopropylphenol. Residues in perirenal fat ranged from 0·8 ppm to 1·9 ppm promecarb and 0·9 ppm to 1·6 ppm 3-methyl-5-isopropylphenol. Residues in diaphragm muscle did not exceed 0·06 ppm. In the feeding trial, the maximum residues induced were 2·2 ppm promecarb and 1·4 ppm 3-methyl-5-isopropylphenol in omental fat of an animal fed for 20 days on a diet containing 20 ppm promecarb.     

DDT and BHC residues in some body tissues of goats, buffalo, and chickens, Lucknow, India

Muscle, liver, brain, and abdominal body fat samples of goats, buffalo, and chickens, all common meat sources in India, were analyzed by gas-liquid chromatography (GLC) for residues of DDT and benzene hexachloride (BHC). A few samples of goat and buffalo bone marrow were also included. Relatively high residue levels were found in body fat and bone marrow compared with other tissues. DDT and BHC residue levels were highest in chicken body fat, averaging 4.157 ppm sigma DDT and 3.879 ppm BHC. DDT content was much higher in goat and buffalo bone marrow than in the corresponding body fat. DDT levels in brain samples were highest (0.138 ppm) in buffalo. p,p'-TDE levels were higher than p,p'-DDE levels in buffalo; overall DDT levels were lowest in goats. BHC residues were generally low in buffalo; alpha-BHC accounted for most BHC residues in brain tissues. Greater accumulations of DDT and BHC were found in leg muscles than in breast muscles of chickens.     

Organochlorine pesticide residues in human milk samples from women living in Northwest and Northeast Mississippi, 1973-75

Organochlorine pesticide analyses were performed on human milk samples obtained from 34 women living in the Mississippi Delta, a high pesticide usage area, and from six women living in Starkville, Mississippi, a low pesticide usage area. Nine women collected samples before and after their babies had nursed so that fat levels and sigma DDT levels could be compared on whole milk and milk fat bases. sigma DDT values were independent of collection time if calculated on a milk fat basis, but not if calculated on a whole milk basis. Thus, the most consistent indicator of DDT residues were values calculated on a milk fat basis. Residue levels for p,p'-DDE, p,p'-DDT, and sigma DDT were significantly different (P less than 0.01) in samples from the two areas. Residues of o,p'-DDT, beta-BHC, and oxychlordane in milk samples from women living in the high pesticide usage area also were significantly different (P less than 0.05). A mean value of 19.17 ppm sigma DDT, found in the milk fat of samples from the high pesticide usage area, is the highest ever reported. Samples from the low pesticide usage area contained a mean level of 2.36 ppm sigma DDT.     

Organochlorine residues in young herons from the upper Mississippi River-1976.

Chicks of great blue herons (Ardea herodias) from four heronaries located near South St. Paul, Royalton, and Wabasha, Minnesota, and La Crosse, Wisconsin, were analyzed for organochlorines, Highest mean wet-weight concentrations, 6.43 ppm PCBs. 1.31 ppm DDE, and 1.90 ppm sigma DDT, were found in the South St. Paul chicks. Among chicks from the other three heronries, most levels were similar, but were significantly lower than levels in South St. Paul chicks. Lowest mean organochlorine levels, 0.37 ppm DDE, 0.38 ppm sigma DDT, and 0.22 ppm PCBs, were found in chicks from Royalton. All birds from South St. Paul and La Crosse contained residues of DDT and TDE whereas only one of the 10 birds from Royalton contained DDT and one contained TDE residues. Five of the 12 birds from Wabasha contained DDT; eight contained TDE. Except for PCB residues in La Crosse heron chicks, the rate of organochlorine residue accumulation in the birds was generally less than the rate of dilution caused by growth.     

Persistence and degradation of chlorfenvinphos,diazinon, fonofos and phorate in soils and their uptake by carrots

Analytical methods are described for the determination of residues of chlorfenvinphos, diazinon, fonofos and phorate in soils and carrots. The insecticides, applied in June 1969 at 2 kg (a.i.)/ha, persisted longer in peaty loam than in sandy loam. After 7 months, the sandy loam contained 1% of the applied diazinon and 20–30% of the applied chlorfenvinphos, fonofos and phorate, the latter as its sulphone; the corresponding figures for the peaty loam were 10, 40–50, 40–50 and 30–40% respectively. None of the residues showed any substantial change from October to January. Although high initial concentrations (up to 50 ppm) of the residues in carrots were diluted by plant growth, it is shown that concentrations >1 ppm could be present in marketable crops 12–14 weeks after application at recommended rates. Carrots harvested 26 weeks after sowing contained <0.2 ppm of all insecticides. In contrast, during the first 15 weeks of crop growth the weights of residues in the carrots increased and remained approximately proportional to the square root of the carrot mean weight. Rates of uptake declined as carrot growth declined and subsequently the amounts of chlorfenvinphos, diazinon and fonofos residues in the carrots changed very little, while phorate sulphone steadily declined.     

Residues of organochlorine insecticides and polychlorinated biphenyls in fish from Lakes Huron and Superior, Canada--1968-76.

Five species of fish from Lake Superior and 12 species from Lake Huron were analyzed for organochlorine pesticides and polychlorinated biphenyls (PCBs) between 1968 and 1975. Mean residues of sigma DDT peaked at 1.72 ppm and 7.60 ppm in lake trout (Salvelinus namaycush) from Lakes Superior and Huron, respectively. By 1975, the mean level of sigma DDT had decreased in lake trout and was highest in bloaters (Coregonus hoi) from both lakes: 1.06 ppm and 1.87 ppm, respectively. Dieldrin levels in fish from Lake Superior changed little over the same period. However, in 1969-70, dieldrin levels in fish from Lake Huron exceeded the 0.3 ppm tolerance level set by Health and Welfare Canada or the Food and Drug Administration, U.S. Department of Health, Education, and Welfare in 5 percent of lake whitefish (Coregonus clupeaformis) and 10 percent of bloaters. By 1975, 50 percent of bloaters caught in Georgian Bay and North Channel had dieldrin levels above 0.3 ppm. PCB residues declined in lake trout and lake whitefish caught in Lake Superior between 1971 and 1975, but increased slightly in bloaters and white sucker (Catostomus commersoni). Mean PCB residues in bloaters caught in Lake Huron in 1969-71 and 1975-76, and splake (Salvelinus fontinalis and S. namaycush) and cisco (Coregonus artedii) caught in 1975 exceeded the 2 ppm tolerance level.     

The metabolism and residues of [14C]Endrin in lactating cows and laying hens

[¹⁴C]Endrin was fed to two lactating cows in a portion of their diet for 21 days. The intake was equivalent to approximately 0.1 mg of endrin per kg of total diet. Excretion of radioactivity in milk, urine and faeces reached equilibrium with intake between 4 and 9 days after starting treatment. Milk residues reached 0.003–0.006 mg/kg, were composed of unchanged endrin and were located in the fat. Muscle residues reached 0.001–0.002 mg/kg. Residues in the fat reached a maximum of 0.1 mg/kg and were due to unchanged endrin. [¹⁴C]Endrin was administered in corn oil to six laying hens for 21 weeks. The intake was equivalent to approximately 0.13 mg/kg of total diet. Ingestion and excretion were almost in balance at 16–20 weeks. Egg residues reached 0.11–0.18 mg/kg, were composed of unchanged endrin and were located in the yolk. Tissue residues were 0.01 mg/kg in breast, 0.1 mg/kg in leg, 0.17 mg/kg in kidney, 0.47 mg/kg in liver and 1.0 mg/kg in fat. The residues were accounted for as unchanged endrin except in liver and kidney in which part was probably due to polar metabolites in the process of excretion. The results show that endrin is much more rapidly metabolised in cows than in hens. The pathways of metabolism were fundamentally the same in both species, the major product being anti-12-hydroxyendrin, which was found un-conjugated in cow urine and faeces and as the O-sulphate conjugate in hen excreta. The only observed difference in primary metabolism was some syfl-12-hydroxyendrin and 12-ketoendrin in cows. This pathway was not detected in hens.     

DDT and inflammatory responses: 1. Influenza infection in mice fed DDT

Mice fed casein diets containing 100 and 200 ppm DDT for 20 days failed to exhibit any signs of DDT intoxication or an impairment of growth. When the mice were infected with influenza A₂ virus, the resulting disease was more severe in the DDT-fed groups as evidenced by increased inflammatory lung oedema and mortality rates. While DDT failed to affect viral replication in the lungs, the increased lung inflammatory oedema was evaluated in relationship to lung histamine content. Following the infection the lung histamine levels decreased; control group 30%; 100 ppm DDT 57%; and 200 ppm DDT 69%. The results indicate that DDT increases release of histamine that accelerates the inflammatory reaction and thus contributes to the mortality caused by influenza. The results suggest that DDT residues stored in tissues can affect inflammatory responses induced by infectious agents.     

Residues of tetrachlorvinphos and its breakdown products on treated crops. III.—Residues on a range of field crops

A wide range of crops including top fruit, cereals, brassicas, root vegetables and cotton from field trials in several countries in 1965, 1966, 1967 and 1968 have been analysed for residues of tetrachlorvinphos (Gardona, trans-homer of dimethyl 1-(2′,4′,5′-trichlorophenyl)-2-chlorovinyl phosphate) foliar insecticide, its isomer and its potential breakdown products. The residues under field conditions were mainly of tetrachlorvinphos, its isomer and 1-(2′,4′,5′-trichlorophenyl)ethan-1-ol in free and sugar-conjugated forms. Tetrachlorvinphos was not unduly persistent on the crops and its initial half-life varied from 2 days on cabbage, to 7 days on potato foliage and to 12 days on pears (after the last of five applications). From one week after the final application onwards the highest residues of tetrachlorvinphos observed were on olives (1 ppm after 18 days after a single application of 0·1 % active material), maize leaf (2·8 ppm at 9·5 weeks after the last of two applications at 3 kg/ha), and cabbage (1·9 ppm at 12 days after the last of three applications at 0·5 kg/ha). The maximum residues of the alcohol in the free form were 3·2 ppm on maize leaf at 8 weeks from the second application at 1·5 kg/ha and in the conjugated form were 1·0 ppm on cauliflowers at 6 days after the last of four applications at 0·5 kg/ha.     

Residues of HCH isomers and DDT derivatives in Israeli milk and their seasonal fluctuations

Residue analysis of milk fat from 12 commercial dairies showed that p,p′-DDE, α-HCH and γ-HCH were the major and most frequent contaminants, at 0.15–0.3 ppm. Beta isomer of HCH was found in the milk in much smaller concentrations (less than 0.05 ppm). Further studies showed that the residue levels of α- and γ-HCH in the milk changed considerably during the 18 months of the experiment. The concentrations fluctuated from a maximum of 1.4–1.6 ppm to as low as 5–10% of these values. The variations in concentration for α- and γ-HCH were very similar, and were found to result from commercial spraying of cows with a formulation of HCH. Three days after spraying two groups of cows with HCH, the residue level rose from 0.02–0.05 ppm to 0.18 ppm. During the next 2–3 months, the concentration of these isomers in the milk fat decreased to 0.02–0.04 ppm. A second spray resulted in an even faster accumulation of α and γ isomers in the milk fat, up to 0.38 ppm, three days after treatment. Comparison between the results obtained from the two groups of cows and those obtained from the analysis of 12 cows showed very small individual variations, with a standard deviation of 15–30% of the mean. The results for DDE were different: its concentration in the milk did not fluctuate so much, and it was similar for all the dairies examined. In goat milk, the concentration of HCH isomers was much lower, not exceeding 0.02–0.05 ppm. The level of DDE was also much lower, 0.02–0.07 ppm.     

The postmortem reductive dechlorination of pp′DDT in avian tissues

Pigeons, Bengalese finches, and Japanese quail were dosed with pure pp′DDT, and their tissues were examined for residues immediately after death, or following storage. DDD residues in livers extracted immediately after death were always low (<5% DDT concentration) and sometimes undetectable. Reductive dechlorination of DDT to DDD occurred postmortem, relatively repidly at 20°C (90% after 8 hr), but more slowly at ?10 and ?20°C. The conversion could not be attributed to bacterial action and was evidently due to processes operating within the cell under anaerobic conditions. During storage at ?12 to ?15°C, reductive dechlorination occurred in brain and in embryos, but did not occur to any significant extent in depot fat or in eggs without embryos. These findings raise questions about the importance of DDD as an in vivo metabolite in birds and other vertebrates. The interpretation of DDD residues in tissues from laboratory and field studies is discussed.     

Mirex residues in bobwhite quail after aerial application of bait for fire ant control, South Carolina--1975-76

Mirex, the organochlorine compound used for control of the imported fire ant (Solenopsis invicta Buren), was applied aerially under supervision of the South Carolina Plant Pest Regulatory Service in October 1975 to a game management area in Hampton County, S.C. Influenced by recent reports indicating that low levels of mirex were toxic to certain nontarget organisms in laboratory studies, authors initiated a program for monitoring mirex residues in bobwhite quail (Colinus virginianus). Pretreatment residues were recorded on a dry-weight basis in bobwhite quail breast and adipose tissue; conversion factors for determining wet-weight concentrations are approximately as follows: fat, 0.77; and breast, 0.29. Residues ranged from 0.000-0.178 ppm and 0.247-2.763 ppm, respectively. Mirex residues in quail adipose tissue showed up to five-fold increase within the first month after treatment and declined thereafter. A residue peak was noticed the spring following mirex treatment, corresponding with insect emergence. Mirex residues in quail collected in summer 1976 following a fall bait application showed slightly higher residue levels than had birds taken in summer 1975; however, little, if any, human food chain contamination would result in the consumption of birds with residue levels found in this study.     

Residues of tetrachlorvinphos and its breakdown products on treated crops. II.—Residues on apples

Apples treated with tetrachlorvinphos (Gardona, trans-isomer of dimethyl 1-(2′,4′,5′-trichloropheny1)-2-chlorovinyl phosphate) insecticide under field conditions in several countries in 1965, 1966 and 1967 have been analysed at intervals after treatment for residues of tetrachlorvinphos itself, its cis-isomer and seven potential breakdown products. Residues of up to 10 ppm of tetrachlorvinphos were detected immediately after the last of three applications of tetrachlorvinphos (diluted to 0.16% active material). The initial half-life of the tetrachlorvinphos was on average about 0.5 weeks under U.K. conditions and only 10% of the tetrachlorvinphos remained unchanged at 2 weeks after application. The overall chemical persistence of the wettable powder formulation was not significantly different from that of the emulsifiable concentrate formulation. Within 8 weeks of the application the residues were mainly of tetrachlorvinphos itself, its cis-isomer and the alcohol 1-(2′,4′-5′-trichlorophenyl)ethan-l-ol, in free and sugar-conjugated forms. The residues of the conjugates of this alcohol (up to 0.92 ppm) were generally present in higher concentration at 6-8 weeks after the application than were the residues of the other components. Whilst residues of other breakdown products were detected on the apples their individual residues were below 0.05 ppm and generally below 0.01 ppm at 6 weeks or more after the last of several applications of tetrachlorvinphos.     

Excretion of DDT residues into milk of the Indian buffalo,Bubalus bubalis (L.) after oral and dermal exposure

Three groups of buffaloes were fed with 20, 100 and 400 mg of p,p′-DDT in their daily rations. The DDT residues in the milk fat of the treated animals showed an initial rapid rise but soon attained a dose-dependent equilibrium. The transfer coefficient of DDT residues in milk at ‘plateau’ levels showed an average value of about 12%. Half-life values for the rate of decline of DDT residues during the post-dosing period were computed according to a two-open-compartment model. Dermal application of p,p′-DDT to buffaloes also resulted in excretion of a significant amount of its residues in milk. TDE was the predominant compound present in milk when buffaloes had ingested p,p′-DDT, whilst p,p′-DDT itself was present in greater quantity than its metabolites when animals were treated dermally.     

Residues of organochlorine pesticides in broilers from feed fortified with known levels of these compounds

p, p'-DDT, HEOD, endrin, heptachlor epoxide, hexachlorobenzene and lindane were fed in combination to day-old broiler chickens at levels of 0.05, 0.15 and 0.30 part/million in the feed, for a period of about 7 weeks. Birds were killed at regular intervals and samples of abdominal fat and other tissues examined for residues of the chlorinated pesticides by gas-liquid chromatography. The lipid content of each sample was determined and the residue levels calculated for the whole tissue and also for the fat contained in the sample. At the end of the 7 weeks (when in practice broilers are slaughtered) residues were highest for heptachlor epoxide, followed by hexachlorobenzene, HEOD, DDT (total), endrin, and lindane. Heptachlor epoxide residue levels in fat were 13 times the levels in the feed, for lindane the ratio was 3.3. Fat residues of each pesticide reached a plateau level relatively quickly, and these levels were proportional to the fortification rates in the feed. HEOD and p, p'-DDT alone were fed to separate groups of birds. No differences in residue build-up of these compounds were found between these groups and the groups that had received these compounds in combination with the other pesticides. The total amounts of each pesticide in the tissues were reduced when the meat was fried, probably by loss of fat during preparation and frying. For p, p'-DDT and heptachlor epoxide also smaller residue were observed in the remaining fat after frying.     

Determination of tricyclohexyltin hydroxide residues in apples and pears

Plictran (tricyclohexyltin hydroxide, Cy₃SnOH) residues in Stark Delicious apples and Passacrassana pears were determined. Field applications were carried out 7, 16 and 28 days before harvest. The analyses were carried out by two procedures: selective determination of the various Sn forms and determination of total Sn. The final spectrophotometric determinations were made as inorganic Sn using dithiol reagent. Average data obtained for apples were from 0.26 to 0.32 ppm of Sn (0.84–1.00 ppm Cy₃SnOH) and for pears from 0.12 to 0.30 ppm of Sn (040–0.99 ppm Cy₃SnOH). A residues half-life of 5–6 weeks for the apples and of 2 weeks for the pears was found.     

Effects of reducing DDT usage on total DDT storage in humans

Agricultural uses of the insecticide DDT were cancelled by the U.S. Environmental Protection Agency December 31, 1972. However, the domestic use of DDT had begun to decline before this action. Beginning July 1969, residues of DDT and its metabolites were measured in human adipose tissue collected through an annual national survey. Levels of total DDT equivalent residues in human adipose have decreased slightly, but the frequencies of finding DDT or its metabolites have remained high. The most marked decline in residue concentration has been found in the youngest age group (0-14 years). Approximately 80 percent of the total DDT equivalent found in this survey was DDE. These data show that the reduction of the agricultural uses of DDT has decreased human exposure to and storage of this chemical.     

Dose-dependent sub-chronic toxicity of diethyl phthalate in female Swiss mice

The experiment was conducted to study the after effects of administering DEP at different doses to female Swiss mice for a period of 90 days. Group I mice were fed on normal diet and water ad libitum. Group II mice were maintained on normal diet mixed with corn oil at 8.25 mg/kg of the diet/day as oil control. Group III, IV and V mice were given diethyl phthalate dissolved in corn oil mixed with the diet at 10, 25 and 50 mg/kg of the diet/day, which is approximately equal to 1.25, 3.125 and 6.25 mg/kg body weight/day. A significant dose dependent increase was observed in serum acid phosphatase (ACP) whereas, serum and liver triglycerides levels showed a significant increase only in the high-dose treated group. Significant dose-dependent increase in serum aspartate and alanine aminotransferase (AST and ALT) and liver glycogen was observed. Serum lactate dehydrogenase (LDH) was significantly increased only in 25 and 50 ppm DEP-treated mice. Liver cholesterol was significantly increased in all the treated groups. Liver histology by light microscopy showed intracellular vacuolations in all the treated groups which was much more evident in the 25 and 50 ppm DEP-treated mice while hepatocellular degeneration and hypertrophy of the hepatocytes was evident in 50 ppm DEP-treated mice. Proliferation of mitochondria and peroxisomes was evident in the electron micrographs of the 10 ppm DEP-treated mice while 25 and 50 ppm DEP-treated mice showed increase in lipid droplets and severe mitochondrial proliferation.     

The effect of CME 134 onSpodoptera Littoralis Eggs and larvae

CME 134, a new benzoylphenyl urea chitin synthesis inhibitor, was less active than diflubenzuron and BAY SIR 8514, when tested againstSpodoptera littoralis eggs by a dipping method. AgainstS. littoralis larvae the compound was tested by feeding treated alfalfa, topical application and contact with crystalline residues on glass, followed by observation until the adult stage. With both 200–250 and 360–440-mg larvae 100% mortality was obtained by one-day feeding of alfalfa treated with 0.15 ppm a.i. Topical application to 100- and 200-mg larvae showed CME 134 to be about five and nine times more active than BAY SIR 8514 and diflubenzuron, respectively. These differences were even much greater in the contact tests. Cotton field plots were sprayed with either CME 134 or diflubenzuron formulations, leaves were collected at different intervals and fed for one day toS. littoralis larvae in the laboratory. 0.0009% a.i. CME 134 residues gave complete kill of 30–50-mg larvae after 5 and 20 days, and 86% kill after 28 days of aging. With 0.003 and 0.009% a.i., complete kill was obtained in 200–250-mg larvae until 50 days after spraying.     

DDE increases the toxicity of parathion to coturnix quail

Adult male Japanese quail (Coturnix coturnix) were exposed to DDE or chlordane in the diet and subsequently dosed with parathion or paraoxon. Pretreatment with 5 or 50 ppm DDE in the diet for 12 weeks resulted in increased cholinesterase (ChE) activity in plasma, but not in the brain. Dietary concentrations of 5 and 50 ppm DDE caused increased susceptibility of quail that were challenged with parathion or paraoxon. The increased mortality resulting from DDE pretreatment was reflected in brain ChE inhibition. The synergistic action of DDE was apparent after 3 days of exposure to 50 ppm DDE and 1 week of exposure to 5 ppm DDE. Birds exposed for 3 weeks to 5 or 50 ppm DDE retained their DDE-potentiated sensitivity to parathion after 2 weeks on clean diet. Chlordane pretreatment resulted in decreased susceptibility (antagonism) to parathion, but not to paraoxon dosage. Implications of differing responses in ChE and mortality among controls, DDE-, and chlordane-pretreated birds after parathion or paraoxon dosage are discussed.