Malathion Treatment Research Articles

Modulation of hepatic glutathione system of enzymes in suckling mouse pups exposed translactationally to malathion.

The present study examines the transmammary modulation of the glutathione system of enzymes in the F1 generation of mouse pups postnatally exposed to malathion. Lactating Swiss albino mice received either 30 or 100 mg malathion kg-1 body wt. (98% pure) for 14 or 21 days postpartum. The acid-soluble sulphydryl content was significantly increased (P < 0.001) in the liver of 14-day-old pups of dams that had received the higher malathion dose. A similar significant increase was seen in the 21-day-old male pups of dams that had received 30 mg (P < 0.05) or 100 mg (P < 0.01) malathion kg-1 body wt. Dams showed an enhanced hepatic glutathione S-transferase activity following treatment with 100 mg malathion kg-1 body wt. for 14 days (P < 0.02) and 21 days (P < 0.001). Pups of either age groups also showed enhanced hepatic glutathione S-transferase activity (P < 0.001). A significant enhancement in glutathione reductase activity was observed with malathion treatment in livers of dams and pups (P < 0.001). However, dams that had received 30 mg malathion kg-1 body wt. daily for 21 days or 100 mg malathion kg-1 body wt. for either 14 or 21 days showed significantly reduced hepatic glutathione peroxidase activity (P < 0.01, P < 0.001). A significant decrease in glutathione peroxidase activity was also observed in the liver of the 21-day-old male (P < 0.01) and female (P < 0.02) pups of dams that were treated with the higher dose of malathion.

Malathion disposition in dermally and orally treated rats and its impact on the blood serum acetylcholine esterase and protein profile

14C-methoxy-malathion with either pure or 50% E.C. formulated malathion were applied orally or dermally at one tenth of their LD50 to two batches of male albino rats. More than 90% of 14C was released with urine after 24 hours. The rest of 14C was detected in the feces, blood, intestines, liver and kidney in a descending order. No significant 14C was detected in other organs. Comparing the oral pure and formulated malathion treatments, there was no significant variation in the rate of disposition or excretion of 14C-malathion. However, the dermal treatment revealed that the 14C-formulated malathion was released faster than the pure one in urine in the first 24 hours; while the 14C-pure malathion showed relatively higher levels in the feces and blood in the first 24 hours. In a third batch of male albino rats, the effect of the same level of dermal treatment by either pure or 50% E.C. formulated malathion on serum acetylcholine-esterase (A. Ch. E.) activity and serum protein profile was studied. The serum A. Ch. E. activity was found to be inhibited to 40% activity after 6 to 24 hours for both treatments. However, after 96 hours the serum of the pure malathion treated rats showed full recovery of A.Ch.E. activity, while the formulated malathion treated showed only 60% activity. The SDS-PAGE analysis showed a differentiation in the serum protein bands of the 48 hours exposed rats to formulated malathion which was confirmed by the scanned gel profile. The FPLC integrated chromatograms proved an initiation of a new protein band accompanied with rearrangement of the albumin and pre-albumin bands. Thus it can be concluded that, the impact on the blood serum protein profile and A. Ch. E. activity can be used as reliable criteria to detect acute toxicity of malathion and other choline-esterase inhibitors in exposed field workers. Further research is needed to elucidate the specificity and sensitivity of such criteria as biomarkers for human exposure.

Reduction of malathion resistance in caged almond moth, Cadra cautella (Walker) (Lepidoptera: Pyralidae), populations by the introduction of susceptible males

Caged populations of the almond moth, Cadra cautella (Walker), that were resistant to malathion were subjected to the release of susceptible males at various ratios. The effects of introducing malathion susceptible males into the population were monitored by determining the LD 50s for 21 day old larvae from each population. F 1 hybrid larvae were found to be intermediate in resistance between larvae from the parental strains, and resistance appeared to be inherited in a codominant fashion. Populations which received only a single release of males were, in general, more malathion susceptible the greater the introduction ratio (except at a ratio of 20:1). Larger populations subjected to repeated introductions of susceptible males showed a clear trend of decreasing larval survival after malathion treatment with increasing release ratio (including the 20:1 ratio). These results indicated that desirable alleles, such as those for insecticide susceptibility, can be introduced into established populations, and that this line of research should be given more emphasis in preventing development of resistance or in ameliorating established resistance.

Quality of stored corn (maize) as influenced by Sitophilus zeamais Motsch. and several management practices

The impact of several simulated management practices (malathion treatment, temperature, moisture content, hybrid, and surface disinfection) for Sitophilus zeamais Motsch. on the quality (biochemical composition) and germination of corn (maize) was studied. Quality was evaluated on the basis of protein, ash, lipid, and total nonstructural carbohydrates content, weight loss, and germination. When the abiotio conditions were favorable for S. zeamais oviposition, larval development, and progeny emergence, the ash, lipid, and protein content of the kernels was increased, as was kernel weight loss. Germination and dry matter were significantly decreased when progeny were present. The differences in nutritional parameters observed here were generally very small, although highly statistically significant. It is not clear whether these differences are biologically significant, although we feel that they indicate meaningful changes that may occur in corn nutrition and quality following infestation by S. zeamais for several generations.

Effect of Several Management Tactics on Adult Mortality and Progeny Production of Sitophilus zeamais (Coleoptera: Curculionidae) on Stored Corn in the Laboratory

A factorial experiment was conducted to examine the effects of temperature, corn hybrid, moisture content of corn, malathion treatment, and presence or absence of surface-contaminating fungi on adult survival, progeny production, progeny weight, and time to 50% emergence of the maize weevil, Sitophilus zeamais Motschulsky. Temperature, moisture content, surface contamination, and malathion significantly influenced maize weevil mortality. Progeny production was affected by these factors as well as by the corn hybrids. Progeny weight and time to 50% emergence were affected only by temperature and moisture content. There were several highly significant interactions, most notably between temperature and moisture content. Temperature, corn hybrid, and moisture content appear to offer the greatest potential for nonchemical control of maize weevil in bulk grain stores.

Alterations in xenobiotic metabolizing enzymes in brain and liver of rats coexposed to endosulfan and malathion

The effects of endosulfan (3 mg kg-1 body wt., i.p.) and malathion (30 mg kg-1 body wt.) and their coexposure on rat hepatic and brain xenobiotic metabolizing enzymes were investigated. Endosulfan was found to induce aminopyrine-n-demethylase (81%) and aniline hydroxylase (59%) activities significantly in liver and to a lesser extent in brain. Malathion treatment induced malathion carboxylesterase activity in both liver (50%) and brain (22%), significantly depleted liver glutathione (35%) content with stimulation of glutathione-S-transferase (50%) and inhibited the activity of mixed-function oxidases. In the coexposed animals, malathion's inhibitory influence on mixed-function oxidases and endosulfan's inhibitory effect on malathion carboxylesterase were found to dominate, while endosulfan potentiated the activity of glutathione-S-transferase significantly in liver (69%) and brain. A similar trend of alteration in coexposed brain was found, but to a lesser extent. A significant inhibition in brain acetylcholine esterase activity (42%) in the coexposed animals suggests that endosulfan may potentiate the toxicity of malathion by interfering with glutathione and carboxylesterase routes of malathion detoxification.

Comparative Fitness of Malathion-Resistant and Susceptible Indianmeal moth (Lepidoptera: Pyralidae)2

Three factors contributing to fitness of a species (fertility, fecundity, and development time) were measured in the susceptible Savlab strain and the &amp;gt; 100-fold malathion-resistant Statesboro strain of the Indianmeal moth, Plodia interpunctella (Hübner). Both fertility (percent egg hatch) and fecundity (eggs/female) were significantly lower in the resistant strain. Percent egg hatch in the two strains was 96.2% and 73.1% for Savlab and Statesboro respectively. Fecundity was 444 eggs/female for Savlab and 321 eggs/female for Statesboro. Development time did not differ significantly (24.2 ± 0.3 and 23.6 ± 0.2 days for 50% emergence). There was no evidence that these differences arose from non-lethal effects caused by malathion treatment to maintain resistance in the Statesboro strain. The differences, while associated with malathion resistance, cannot be unequivocally attributed to the presence of the resistance gene. When the intrinsic rate of increase (rm) was calculated using an iterative computer program, Statesboro had a significantly lower rate (0.1734 ± 0.0016) than did Savlab (0.2048 ± 0.0014). Similar measurements were performed with progeny from reciprocal F1 crosses. While some parameter's values were closer to Statesboro or Savlab an apparent mating incompatibility suggests that using the data from F1 crosses is premature until this question is resolved.

Some macromolecular abnormalities developed by the interaction of malathion and permethrin and subsequent refeeding in Tribolium castaneum larvae

AbstractThe effects of sublethal treatments of malathion and malathion + permethrin combinations on activities of acetylcholine esterase (ChE), carbohydrate‐metabolizing enzymes (amylase; lactate dehydrogenase, LDH), protein‐metabolizing enzymes (alanine and aspartate aminotransferase, ALAT, ASAT), as well as acid and basic phosphatases (AcP and AkP, respectively), and Kreb's cycle enzymes (isocitrate dehydrogenase, ICDH) were studied on sixth instar larvae of the red flour beetle, Tribolium castaneum. In addition, the levels of lipid, cholesterol, glucose, glycogen, proteins, free amino acids (FAA), urea, and nucleic acids (DNA and RNA) were determined. Malathion (400 ppm) increased the activity of LDH (53%), as well as the concentrations of FAA (31%) and urea (39%). Malathion treatments of 400 ppm decreased the glucose (20%) and glycogen (24%) content but did not affect other enzymes and biochemical components. Permethrin (200 ppm) and malathion (20 ppm) mixtures increased the activities of ChE (708%) and LDH (55%), and raised the concentrations of FAA (26%), urea (24%), glucose (23%), lipid (14%), cholesterol (21%), DNA (24%), and RNA (8%). The decrease in AcP activity and in glycogen concentration observed with malathion was sustained by permethrin in the mixture. Permethrin + malathion mixtures also depressed the levels of AkP (30%), ICDH (24%), and glycogen (36%). The intensity of effects commensurated with the dose and duration of insecticide exposure. Refeeding showed tendencies towards normalization of various biochemical parameters.

Field Comparison for Rangeland Grasshopper Control, 1986

Abstract Onsite mixing and cleanup are generally considered easier with aqueous formulations than with formulations requiring diesel fuel, kerosene, or fuel oil diluents. To evaluate performance and ease of handling, the Sevin XLR-Plus formulation of carbaryl was applied at 0.50 lb (AI)/acre (20 fl oz mix/acre containing 16 fl oz form, and 4 fl oz water) to a 160 acre plot near Belle Fourche, S. Dak., 15 Jul. This treatment was compared with a standard rangeland treatment of 0.58 lb (AI)/acre of malathion ULV concentrate (8 fl oz/acre) applied 12-14 Jul to 3,200 acres of rangeland 7 miles away. Both treatments were applied from a Cessna Ag Truck aircraft operating at 120 mph and through flat-fan stainless steel Teejet nozzle tips from an altitude of 50-75 ft with a swath of 100 ft. Twelve 8003 tips directed straight down and operating at 38 psi were used for the carbaryl treatment and eight 8002 tips directed 45° into the wind and operating at 41 psi were used for the malathion treatment.

Induction of polygenic mutations affecting viability in Drosophila melanogaster after dichlorvos, malathion and ethyl methanesulfonate treatments

Induction of polygenic mutations affecting viability in Drosophila melanogaster after dichlorvos, malathion and ethyl methanesulfonate treatments

Effect of malathion-bait mixture on two parasitoids of the Florida red scale, Chrysomphalus aonidum (L.)

Experiments with laboratory populations have shown that immature stages of the hymenopterous parasitoids, Aphytis holoxanthus DeBach and Pteroptrix smithi (Compere) were unaffected by a malathion-bait mixture (0 · 13% malathion) applied to their host, Chrysomphalus aonidum (L.). However, the emerging adults of A. holoxanthus were highly susceptible and it was clearly shown that malathion absorbed in the scale cover of the host was responsible for the lethal effect. Similar results were obtained with parasitized scale insects which were exposed in a commercial citrus grove to ground spray of malathion (1 · 3% malathion). An experiment with natural populations of both parasitoids in the citrus grove clearly demonstrated the susceptibility of A. holoxanthus to malathion-bait spray and were consistent with the above-mentioned laboratory experiments. The results are discussed in the light of the predominant status of P. smithi as a natural enemy of the Florida red scale in citrus groves in Israel. No delayed effects related to fertility, sex ratio and life expectancy of both parasitoid species which survived the malathion treatment were observed.

Effect of malathion on some kinesiological parameters of the gastrocnemius muscle of frog, rana hexadactyla (lesson) and the antagonistic action of atropine

Selected kinesiological parameters were studied in the gastrocnemius muscle of frog, R. hexadactyla Lesson, under different treatments with malathion and atropine. There is an apparent decrease of twitch amplitude, half contraction time, half relaxation time, twitch duration and fatigue time in control muscle during malathion treatment. In the denervated muscle, twitch amplitude, latency period, and fatigue time were lowered, with elevated phases of contraction and relaxation time. However, all these parameters except fatigue time showed an elevatory trend when atropine was given along with malathion revealing its antagonistic action against malathion toxicity. All these results indicate that the action of malathion is similar to that of a pharmacologically active myo- and neurotoxic agent.

Biochemical and haematological changes following malathion treatment in the freshwater catfish Heteropneustes fossilis (Bloch)

Male specimens of H. fossilis were exposed to a concentration of 8 mg litre −1 of malathion in their aquarium water for 16 days during the early post-spawning phase. Its effects on glycogen of liver, testes and muscle, glucose and free fatty acids (FFA) in plasma, spleeno-somatic index (SSI), red blood corpuscle (RBC) and haemoglobin (Hb) were examined. Reduced levels of liver and muscle glycogen, associated with increasing plasma glucose, were noticed after 4 and 8 days of treatment but, after 16 days, a recovery was observed. Testicular glycogen did not respond to malathion exposure. Plasma FFA was also unchanged for 4 and 8 days of treatment but a higher level was recorded after 16 days' exposure. RBC and Hb were reduced following the 4-day exposure; however, no apparent change in their level was observed after 8 and 16 days' exposure. The SSI was also reduced during the 4- and 8-day treatments but 16 days' exposure caused the level to return to normal. Thus, this study demonstrates that, after prolonged exposure, H. fossilis develops a tolerance and partially recovers from the stress condition. In the initial stages carbohydrate was used as an energy source to meet the stress situation, while, in the later phase of exposure, FFA served as the major source of energy.

Atypical growth in Periplaneta brain after malathion treatment.

Atypical growth in Periplaneta brain after malathion treatment.

Subchronic malathion treatment effects on rat intestinal functions.

Subchronic malathion treatment effects on rat intestinal functions.

Slurry Treatments on Grain Seeds, 1982

Abstract The primary objective of these tests was to evaluate the effectiveness of Lorsban and Reldan in comparison to methoxychlor and malathion treatments for protection of seeds when treated seeds were exposed to insects in (1) single treatment exposures (STE) and in (2) multiple treatment exposures (MTE), with all containers of treated grain seed stored together. Gustafson Captan 30 DD was applied to 10-lb lots of corn, grain sorghum, and wheat seed in a Batch Lab Treater. Insecticides were added to the slurry treatment mixture as needed for calculated rates. Duplicate 10-lb lots of seed were prepared and stored at ambient room temp for 2 wk before use in STE tests. Each 10-lb lot of treated seed was divided into five 2-lb samples, and each of these was put into a plain paper bag. Five 2-lb bags of the same kind of seed and treatment were placed upright in a 10-qt aluminum pail, which served as an infestatiogn chamber for exposure to insects. Twenty-five laboratory-reared adults of each species of beetles and 25 mature moth larvae were placed in the center of the test chamber and allowed to move freely about the chamber to infest seed as they desired. Each aluminum pail was covered with black cloth held in place with two large rubber bands. All prepared test chambers were kept in a room maintained at 80°F and 50 to 60% RH for 2 weeks before seeds were sieved gently to remove insects. Although all live insects present in each bag of seed were counted and the number recorded, infestation data are shown as the average number of insects in 10-lb duplicate lots of seed. After removing insects, five 2-lb samples were put together in large paper bags to reconstitute each duplicate lot of treated seed. The bags of seed were held at ambient room temp to age 3 months before use in MTE tests. In the latter, 10-lb treatment lots of each kind of seed were placed at random in a 128 ft3 wooden storage chamber held outdoors without benefit of temperature or humidity control. Each chamber was infested initially with 50 insects of each test species per duplicate 10-lb lot of seed; the same number of insects were used to reinfest chambers after 30- and 60-day exposures. Seeds were sieved after exposure to insects for 90 days, and the number of live insects in each 10-lb lot of seed were recorded.

Biochemical studies of some cell wall associated enzymes in malathion treated germinating seeds ofVigna sinesis(L): effect of IAA and GA3supplementation

Malathion treatment of the seeds of Vigna sinensis (L), above 50 ppm decreased the seedling growth and respiration rate; it is accompanied by a significant alteration in the activities of different cell wall associated hydrolytic enzymes in the roots of the 72 hour germinated seeds. On the simultaneous application of either of the plant hormones (IAA or GA3) with different concentrations of malathion, it was found that there was a trend to overcome the malathion‐caused inhibition on seedling growth pattern and respiration rate in the roots of the seeds. It was also found that the treatment of the seeds with plant growth hormones, at 100 ppm malathion exposure, helps to restore the normal activities of some cell wall associated hydrolytic enzymes, which showed otherwise significantly altered activities. Above 100 ppm malathion exposure on the seeds, the plant hormones gradually lose their efficiency to counteract the malathion elicited effect on the studied parameters in the roots of the seeds.

FIELD EXPERIMENTS ON THE TOXICITY OF ACEPHATE FOR CONTROL OF GRASSHOPPERS (ORTHOPTERA: ACRIDIDAE) ON RANGELAND

AbstractField tests were used to evaluate the efficacy of liquid acephate in aerial applications to control grasshoppers on rangeland. An antidrift additive applied with the treatment was also evaluated. A rate of 105 g AI/ha of acephate at volumes of 2337, 1899, and 1461 mL of mix/ha with the addition of Nalco-trol®resulted in control statistically as good as the standard malathion treatment of 653 g AI/ha. Two formulations of acephate applied at the rate of 105 g AI/ha in a volume of 2337 mL/ha were compared and resulted in statistically comparable mortalities; both formulations of acephate resulted in excellent control 10 days after treatment.

Effect of Continuous Exposure of Malathion-Resistant Red Flour Beetles (Coleoptera: Tenebrionidae) to Malathion-Treated Wheat or Wheat Exposed to Treated Surfaces1

Adults of susceptible (S) and malathion-resistant (R) strains of Tribolium castaneum (Herbst) were exposed continually to wheat treated with 8 ppm malathion dust or liquid, or wheat 3-cm deep above plywood panels treated with 0.05 mg/cm2 malathion. Controls consisted of S-, and R-strains of insects exposed to untreated wheat. After 1, 2, 4, and 8 weeks of storage at 21°C, results for each treatment were analyzed for comparison of insect numbers, seed germination, moisture content, seed damage, and seed-borne microflora. Virtually all (>98%) adult T. castaneum in the untreated wheat controls survived for 8 weeks, when the R-strain had produced five times as many larvae as the S-strain. Few susceptible insects in the panel: wheat treatments and none in the grain:malathion treatments survived. Insects of the R-strain in both the panel and dust treatments had ca. 30% mortality by 1 week; this remained constant for 8 weeks. Mortality of R-strain adults in the liquid treatment was 48, 84 and 90% after 1, 2, and 4 weeks, respectively; few larvae were observed. There was negligible seed damage in all treatments by 8 weeks of storage; moisture content in all treatments remained between 16% and 17% and was similar throughout the study. Seed germination declined by ca. 10% in the malathion liquid treatment. Seed infection by the storage fungus Aspergillus glaucus group was up to 9X greater on malathion-treated seed than on untreated seed probably because the presence of living insects inhibited fungal growth. Malathion applied to wheat as a liquid drip during grain movement could offer significant reduction in malathion-resistant T. castaneum and, under some conditions, could produce short-term control.

Sensitivity of different strains of Drosophila melanogaster to endosulfan and malathion

Four Drosophila melanogaster populations, two of them (ER1 and ER2) previously selected for adult resistance to endosulfan, were examined for response to endosulfan and malathion treatment. Both insecticides were fed to larvae and adult males and females to test their toxic capacity. Our results show that malathion is more toxic than endosulfan, that adult males are more sensitive to both insecticides than females, and that resistance of ER1 and ER2 strains is restricted to the insecticide to which they had been exposed previously (endosulfan).