Parathion mixtures

DOT/UN/NA/IMCO shipping Methyl parathion, liquid (DOT) Methyl parathion mixture, dry (DOT) methyl parathion, solid (DOT) UN 3017 organophosphorus pesticides, liquid, toxic, flammable, not otherwise specified HSDB 1999 RTECS 1989... 

Qiao, G. L., Brooks, J. D., Bayne.s, R. E., Monteiro-Rivierc, N. A., Williams, P. L and Riviere, J. E. (1996). The use of inccha-nistieally defined chemical mixtures (MDCM) to assess component effects on the percutaneous absorption and cutaneous disposition of topically-exposed chemicals. I. Studies with parathion mixtures in isolated perfused porcine. skin. Toxicol. Applied. Pharmacol. 141, 473 86. 

PARATHION AHO COMPRESSED GAS MIXTURE PARATHION-HETHYL see METHYL PARATHIOM PARIS GREEK see COPPER ACETOARSEHITE PCB s see POLYCHLORIHATEO BIPHENYLS... 

Mental disturbances have been reported after organophosphate exposure. Neuropsychiatric symptoms occurred in two aerial applicators, one of whom used methyl parathion as well as other insecticides. One of these pilots had high levels of exposure to a mixture containing methyl parathion, toxaphene, and Dipterex when his clothing became saturated when the tank of his aircraft accidentally overflowed. Several months after the accident, the subject complained of anxiety, dizziness, emotional lability, and frequent and severe disagreements with family members and associates. Similar observations had been... 

Ortiz D, Yanez L, Gomez H, et al. 1995. Acute toxicological effects in rats treated with a mixture of commercially formulated products containing methyl parathion and permethrin. Ecotoxicol Environ Safety 32 154-158. 

Of the three organic phosphorus insecticides—hexaethyl tetraphosphate, tetraethyl pyrophosphate, and parathion—the first two have been shown to be mixtures (36) that contain tetraethyl pyrophosphate as the principal active ingredient. Several methods have been proposed for the determination of this compound in the commercial products (25, 35). All are based on the separation of the tetraethyl pyrophosphate from the related ethyl phosphates, followed by its hydrolysis to diethyl orthophosphoric acid and titration with standard alkali. Both hexaethyl tetraphosphate and tetraethyl pyrophosphate are soluble in water and are rapidly hydrolyzed to monoethyl and diethyl orthophosphoric acid. This rapid hydrolysis to nontoxic products greatly limits the duration of the in- secticidal effectiveness of tetraethyl pyrophosphate, but it also eliminates the danger of toxic residues on the crops treated. 

E.K.C. 4835 is N-(l -naphthylj-ethylenediamine dihydrochloride. Recent chromatographic evidence indicates that the final colored reaction product from technical grade parathion may be a mixture of at least three and possibly four components. 

On Delicious apples the initial residues were 0.9 and 0.4 p.p.m. in plots 7 and 10, respectively, both of which were sprayed with 1.25 ounces of parathion. The difference between the two plots was consistent throughout the individual trees sampled. The spray mixture used on plot 7 also contained DDT, while that used on plot 10 contained only parathion. These plots showed the same relative magnitude of residues 18 days after spraying, and at harvest, 74 days after the spraying. Plot 11, sprayed with 0.6 ounce of parathion. showed an initial residue of 0.3 p.p.m. 

Table III shows the parathion residues on Jonathan and Starking Delicious apples from seven spray plots in the Mississippi Valley. Identical treatments were used on both varieties. The Starking variety showed a slightly lower parathion residue than the Jonathan. The difference was not great, however. In general, the residue after the final spraying was proportional to the concentration of parathion in the spray mixture. The exception is plot 4, sprayed with 2 ounces of parathion with nicotine-bentonite-oil, which shows a residue approximately equal to that obtained on plots sprayed with 4 ounces of parathion, alone or in combination with DDT (plots 11 and 12). The residue 2 weeks after spraying was only one quarter to one third of that found immediately after spraying, and 46 days after spraying only one plot (No. 14 sprayed with 8 ounces of parathion) showed a residue significantly in excess of 0.1 p.p.m.

In the Mississippi Valley the studies included sprays containing as much as 8 ounces of parathion in 100 gallons. When 4 ounces or less of parathion were used, and no spray was applied less than 40 days before harvest, parathion residues were generally less than 0.2 p.p.m. Increasing the concentration of parathion in the spray mixture or decreasing the time interval between the last spray and harvest sometimes resulted in heavier residues. 

The amount of parathion spray residue on soft fruits is roughly proportional to the length of time between date of application and date of analysis. Parathion spray residue was lost from the surface of Delicious apples at the rate of 80 to 85% in 12 to 13 days and 93 to 100% in 30 to 32 days. The rate of loss was the same for 1-pound as for 4-pound concentrations. Fifty-five samples, collected from commercial orchards, were analyzed. No significant relationship was found between the number of days between spraying and analysis and the parathion residue. There was no significant difference in parathion residue due to the concentration of the spray mixture used. All residues were only a fraction of 1 p.p.m. 

Spray programs of 1 and 4 pounds of 25% wettable parathion powder per 100 gallons of water were applied to Delicious apples on July 2 (plots 1 and 2). Samples were taken as soon as the fruit became dry and at 10- to 13-day intervals for a period of 32 days. These plots were sprayed again on August 3 with the same mixtures and resampled over a 30-day period (plots 3 and 4). The results and the percentage of loss of parathion are shown in Table III and Figure 1. 

In the adsorption with Tenax alone satisfactory results were obtained, while in the presence of mineral oil a considerable proportion of the organophos-phorus pesticides (particularly Malathion and Parathion-methyl) was not adsorbed and was recovered in the filtered water. This drawback can be overcome by adding a layer of Celite 545 which, in order to prevent blocking of the column, is mixed with silanised glass wool plugs. A number of analyses of surface and estuarine sea waters were carried out by this modified Tenax column and simultaneously by the liquid-liquid extraction technique. To some of the samples taken, standard mixtures of pesticides were also added, each at the level of 1 xg/l (i.e., in concentration from 13 to 500 times higher than that usually found in the waters analysed). One recovery trial also specifically concerned polychlorobiphenyls. The results obtained in these tests show that the two extraction methods, when applied to surface waters that were not filtered before extraction, yielded very similar results for many insecticides, with the exception of compounds of the DDT series, for which discordant results were frequently obtained. 

With respect to C-parathion and Cl-toxaphene, protease-liberated flavoprotein was significantly more active than phosphate buffer in photodegrading these chemicals to ater-soluble products (Tables II and III). The amount of C-water-soluble products formed from parathion was 5-7 times greater in the presence than in the absence of flavoprotein. It should be noted that the presence of FMN in the mixture caused a slight grange in amount of water-soluble products formed (Table II). 

Because each herbicide may degrade during volatilization, it is interesting to compare the cumulative volatilization of the parent contaminant and its metabolites. This behavior was studied in a wind-tunnel experiment by Wolters et al. (2003) for a mixture of parathion, terbuthylazine, and fenpropimorph, as well as for the metabolites fenpropimorph acid and desethyl-tetrabuthylazine. Figure 8.6... 

Atrazine (Aatrex 80W), alachlor (Lasso E.C.) 2,4-D ester (Weed-one LV4 E.C.), trifluralin (Treflan E.C.), carbaryl (Sevin 50W) and parathion (Security 15W) were blended, individually and as mixtures, with 60 L of water and 15 kg of sandy loam soil in 110 L... 

Mixtures had an inhibitory effect with the most dramatic being the degradation of 2,4-D ester, trifluralin and parathion. 

Some hazardous wastes, or mixture of hazardous wastes (such as cyanides, hydrogen sulfide, and parathion) are extremely or acutely hazardous because of their high acute toxicity. These extremely hazardous wastes, if human exposure should occur, may result in disabling personal injury, illness, or even death. 

Chaturvedi et al. (1991) studied the effects of mixtures of parathion, toxaphene, and/or 2,4-D on the hepatic mixed-function oxygenase in ICR male mice. They found that a 7-day toxaphene pretreatment enhanced the hepatic biotransformation of parathion and its metabohte paraoxon, both in the presence and absence of NADP. However, in the absence of NADP the enhancement was minor. The authors suggested that toxaphene induced the metabohc pathways of parathion and paraoxon involving the mixed-function oxygenase and that paraoxonase is not involved in the... 

Chaturvedi (1993) also examined the effect of mixtures of 10 pesticides (alachlor, aldrin, atrazine, 2,4-D, DDT, dieldrin, endosulfan, lindane, parathion, and toxaphene) administered by oral intubations or by drinking water on the xenobiotic-metabolizing enzymes in male mice. He concluded, The pesticide mixtures have the capability to induce the xenobiotic-metabolizing enzymes, which possibly would not have been observed with individual pesticides at the doses and experimental conditions used in the study. ... 

We have examined whether the sulfur that was bound to the proteins of a reconstituted system from the liver of phenobarbital-treated rats was bound to both the reductase and cytochrome P-450. I this experiment, the reconstitued system was incubated with [ s] parathion. The reaction mixture was dialyzed and applied to a Sephadex G-25 column to remove the last traces of unreacted parathion and its noncovalently bound metabolites. The protein fraction from the Sephadex column was reduced in volume and subjected to SDS-polyacrylamide gel electrophoresis in the absence of either dithiothreitol or mercaptoethanol. The results are shown in Figure 5. There was considerable protein and radioactivity at the origin. This material at the origin represents an aggregate of reductase... 

Figure 4. Linearity of the metabolism of parathion and benzphetamine by a reconstituted monooxygenase oxidase enzyme system from rabbit liver. The 0.5-mL reaction mixture contained 50 fig of sodium deoxycholate, 15 iig of dilauroyl l-5-phosphatidylcholine, 1.5 units of NADPH-Cytochrome c reductase, 0.5 nmol of Cytochrome P-450, 0.05M Hepes buffer (pH 7.8), 0.015M MgCh, O.lmU EDTA, and 5 X lO M [ethyl- C] parathion or / X 10 M benzphetamine.

Figure 6. Elution profile of protein, radioactivity, and thiocyanate from a Sepha-dex G-25 column of reconstituted monooxygenase system from rat liver that had been incubated with [ 5] parathion. The 5-mL incubation mixture contained 20 nmol Cytochrome P-450 (specific activity 16.4 nmol/mg protein), 5 units NADPH-Cytochrome c reductase, 600 fig dilauroyl L-3-phosphatidylchoUne, 600 fig sodium deoxycholate, and 1 X IO M p 5] parathion. The remainder of the incubation mixture is described in Figure 4. The incubation time was 5 min. One-milliliter fractions were collected. The radioactivity (x) represents cpm/0.1 mL. The OOggo (o) was measured on each 1-mL fraction (20).

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