• Archives of Pharmacal Research
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• v.9 no.3
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• pp.175-181
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• 1986

Four technical grade organophosphate pesticides (Fenitrothion, Fenthion, Dizninon and EPN) were investigated for their effects on the murine immune function. Among the immunotoxicological assay parameters of NIEHS, humoral immune parameter and pathotoxicological indicators were examined in this study. Subchronic exposure of rodents to these pesticides resulted in marked suppression of humoral immune function and moderate histological changes of lymphoid organ any significant alterations of clinical status.

• Journal of Environmental Science International
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• v.6 no.2
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• pp.183-187
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• 1997

Organophosphate pesticides were extracted with 70% acetone and then transferred to dichloromethane. Extracts were applied to open-column chromatography with florisil. The florial extract was analyzed by gas chromatography with nitrogen-phosphorus detector(GC/NPD). Recoveries of the 18 organophosphate pesticides were ranged from 88.7% to 100. 0% for the narrow-bore capillary GC(Ultra-21. The minimum detectable level of this analytical method was 0.019 - 0.035 mg/kg. Sample throughput(extraction, open-column chro- matography, and GC analysts) was decreased considerably (8h per sample).

• Archives of Pharmacal Research
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• v.9 no.3
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• pp.183-187
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• 1986

Some of organophosphate pesticides which are the most heavily used in Korea, were examined for their effects on the murine immune system. Immunotoxicological assay parameters adaopted in this study were Arthus reaction for humoral immunity, delayed type hypersensitivity reaction for cell mediate immunity, carbon clearance for macrophage function and susceptiility to tumor challenge. Subchronic exposure of rodents to the pesticides resulted in the marked suppression of immune functions and enhancement of susceptibility to tumor challenge. Among the pesticides tested (fenitrothion, fenthion, diazinon and EPN), fenitrothion was the most suppressive in Arthus and delayed type hypersensitivity reaction.

• Journal of Korean Society of Forest Science
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• v.99 no.2
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• pp.179-185
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• 2010

Organophosphate pesticides inhibit cholinesterase. It is likely that application of organophosphate pesticides affect behavior of arthropods. This study aimed to find changes in foraging behavior of ants due to application of fenitrothion, one of the widely used organophosphate pesticides. Foraging activity (FA) of ants was observed using bait cards in a pesticide sprayed pine stand and in an unsprayed stand before and after aerial application of fenitrothion in 2003 and 2004. Ant abundance and species richness of ants were also monitored using pitfall traps during the activity season in 2003 and 2004. There was not a significant decrease in abundance and species richness after the application of fenitrothion. However, FA of an ant, Paratrechina flavipes (Smith), which was abundant enough to be statistically compared, was depressed from 2 hours to 10 days after application of the pesticide. FA was fully recovered at day 14 in 2003, and was partially recovered at day 18 and fully at day 31 in 2004. FA of other ant species also decreased significantly during the FA depression period of P. flavipes. On the bait cards, workers of the species responded dully to baits during the FA depression period. Despite the decline in activity, alertness of P. flavipes to other species did not decrease even during the FA depression period.

• Korean Journal of Pharmacognosy
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• v.23 no.2
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• pp.106-114
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• 1992

The acute toxicity and the effect of steam distillate obtained from several plant mixtures (G-3) on the reactivation of brain, lung, and blood acetylcholinesterase (AChE) activity, and recovery from other toxic symptoms following intoxication by organophosphate pesticides were investigated in mice and mudfish. Administration of G-3 $(50{\sim}100\;ml/kg,\;i.p.)$ immediately or 30 min prior to Diazinon or Sumithion treatments, respectively, resulted in a significant reactivation of AChE activity in brain, lung, and blood, their potencies being almost equipotent to those of 2-PAM, one of well-known antidotes. G-3 itself exhibited almost no acute toxicity even at the highest dose employed, and without effect on the inhibition of hepatic drug metabolism function following organophosphate administrations. G-3 showed a significant diminution of the death rate in mudfish as well as in mice intoxicated by Diazinon.

• Journal of Apiculture
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• v.34 no.4
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• pp.305-313
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• 2019

Honey bees (Apis mellifera) forage in agricultural areas, and are exposed to diverse pesticide poisoning. Toxic effects on Apis mellifera of different groups of pesticides were tested in the laboratory; fungicide (Metconazole), herbicide (Glyphosate), acaricide (Amitraz), organophosphate insecticide(Fenitrothion) and neonicotinoid insecticides(Thiacloprid, Thiamethoxam, Imidacloprid, Acetamiprid, Dinotefuran and Clothianidin). Commercial formulations were serially diluted from the recommended concentration (RC) to 10-6 times to carry out feeding and contact tests. Toxicity was transformed into lethal dose (LD50) and hazard question (HQ). The acute toxicity of pesticides showed similar patterns between feeding and contact tests. But feeding tests showed greater toxic to honey bee than contact test. The organophosphate and nitro-neonicotinoid insecticides were highly toxic with HQ values ranging greater than 1. However, cyano-neonicotinoids of Thiacloprid and Acetamiprid showed low toxicity. Even at the RC, 24 hr mortalities were 18 and 30%. The acaricide (Amitraz) showed intermediate level of toxicity at RC but negligible at the concentration lower than 10-1 times. A fungicide(Metconazole) and herbicide(Glyphosate) showed minimal impacts. The results imply that the selective use of pesticides could help conservation of pollinators in agricultural production systems.

• Journal of Society of Preventive Korean Medicine
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• v.4 no.2
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• pp.285-293
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• 2000

Objectives: We have accomplished a clinical research about counteracting the pesticides intoxication using oriental medical method and treatment. And we observed the preventive effect of Gamdu-tang(甘豆湯) to intoxication of Organophosphorus Insecticides. Material and Methods: The subjects were 8 volunteers who were healthy and not taking medications. we observed change of cholinesterase(ChE) activity in serum of them after exposed to pesticides Results and Conclusions : In this study of the preventive effects of Gamdu-tang(甘豆湯) on the intoxication of Organophosphate Insecticides, we evaluated that the decreasing value of ChE activity after spraying insecticides of Gamdu-tang medication group was smaller than non-medication group, but it was less significant(P>0.05 P<0.1). We had a difficult to gather participant in this study, so it's necessary for us to get together more larger group in the next study.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.946-951
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• 2008

The opd gene, encoding organophosphorus hydrolase (OPH) from Flavobacterium sp. capable of degrading a wide range of organophosphate pesticides, was surface- and intracellular-expressed in Synechococcus PCC7942, a prime example of photoautotrophic cyanobacteria. OPH was displayed on the cyanobacterial cell surface using the truncated ice nucleation protein as an anchoring motif. A minor fraction of OPH was displayed onto the outermost surface of cyanobacterial cells, as verified by immunostaining visualized under confocal laser scanning microscopy and OPH activity analysis; however, a substantial fraction of OPH was buried in the cell wall, as demonstrated by proteinase K and lysozyme treatments. The cyanobacterial outer membrane acts as a substrate (paraoxon) diffusion barrier affecting whole-cell biodegradation efficiency. After freeze-thaw treatment, permeabilized whole cells with intracellular-expressed OPH exhibited 14-fold higher bioconversion efficiency ($V_{max}/K_m$) than that of cells with surface-expressed OPH. As cyanobacteria have simple growth requirements and are inexpensive to maintain, expression of OPH in cyanobacteria may lead to the development of a low-cost and low-maintenance biocatalyst that is useful for detoxification of organophosphate pesticides.

• The Korean Journal of Pesticide Science
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• v.18 no.2
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• pp.95-103
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• 2014

In this study, we monitored the residues of organophosphate pesticides (OP) in eight fruit vegetables grown in Korea, and assessed risk levels of acute and chronic exposure of OP through the consumption of fruit vegetables. Chlorpyrifos, EPN, methidathion and phosphamidon in eight fruit vegetables were detected in this study. The results of cumulative assessment of national estimated short term intake for acute exposure of OP were due to the following order; eggplant, tomato, squash and cucumber. Total theoretical maximum daily intake calculated at first step of chronic exposure assessment for registered OP in Korea was 76.14%, compared with acceptable daily intake ADI) based on chlorpyrifos. In addition, total national estimated maximum daily intake calculated at second step of chronic exposure assessment was 13.949%, compared with ADI. Third chronic assessment was conducted by probabilistic approach using OP residues detected in eight fruit vegetables and showed that total exposure risk was very low, corresponding to 0.0001% compared to ADI. Based on those finding, the risk of organophosphate pesticides in fruit vegetables was considered quantitatively negligible. In future, further investigation to expand the target should be followed to do more accurate and detailed risk assessment.

• Journal of Environmental Health Sciences
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• v.43 no.4
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• pp.280-297
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• 2017

Objectives: We assessed pesticide exposure levels according to cultivation and crop type and investigated agricultural factors related to exposure. Methods: The participants, 341 male and 127 female farmers, were divided into three groups by cultivation crop type: chili greenhouse, cucumber greenhouse, and orchard. We collected questionnaires, socioeconomic characteristics and agricultural factors, and spot urine. Pesticide exposure was examined using four organophosphate and four pyrethroids urinary metabolites: dimethylphosphate, dimethylthiophosphate, diethylphosphate, diethylthiophosphate, Cis and Trans-3-(2-2dichlorovinyl)-2, 2-dimethylcyclopropane carboxylic acid, 3-phenoxybenzoic acid (3-PBA), Cis-3-(2-2dibrmovinyl)-2, and 2-dimethylcyclopropane carboxylic acid. Each metabolite was summed ${\Sigma}DAP$ and ${\Sigma}PY$ according to the chemical class. Results: Urinary metabolite detection rates and concentrations were similar between the greenhouse groups, but the orchard group was different. Similar 3-PBA detection rates were found in the three groups, but the geometric mean was very high in the orchard group compared to the two greenhouse groups. 3-PBA concentration in the orchard group was $4.11{\mu}g/g$ creatinine; the chili and cucumber greenhouse groups were 1.27 and $1.16{\mu}g/g$ creatinine, respectively. ${\Sigma}DAP$ was significantly associated with cultivation crop type and seasonal variation, but ${\Sigma}PY$ was not relevant. Conclusions: Our results suggest that cultivation and crop type may be correlated with different pesticide types and exposure levels. Furthermore, seasonal factors were related as potential factors influencing the level of organophosphate metabolites, but not for pyrethroid metabolites.