• Food Science and Biotechnology
• /
• v.17 no.3
• /
• pp.547-552
• /
• 2008

The detection of carbamate (carbofuran, carbaryl, benfracarb, thiodicarb, and methomil) and organophosphate (diazinon, cadusafos, ethoprofos, parathion-methyl, and chlorpyrifos) pesticide residues with very low detection limits was carried out using surface plasmon resonance (SPR) based equipment. The capacity to develop a portable SPR biosensor for food safety was also investigated. The applied ligand for the immunoassays was polyclonal goat anti-rabbit immunoglobulin (IgG) peroxidase conjugate. Concentration tests using direct binding assays showed the possibility of quantitative analysis. For ligand fishing to find a proper antibody to respond to each pesticide, acetylcholinesterase (AChE), and glutathione-S-transferase (GST) were tested. The reproducibility and precision of SPR measurements were evaluated. With this approach, the limit of detection for pesticide residues was 1 ng/mL and analysis took less than 11 min. Thus, it was demonstrated that detecting multi-class pesticide residues using SPR and IgG antibodies provides enough sensitivity and speed for use in portable SPR biosensors.

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

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

• Journal of The Korean Society of Clinical Toxicology
• /
• v.20 no.1
• /
• pp.25-30
• /
• 2022

In this study, we report the case of a 59-year-old male patient with organophosphate pesticide poisoning. He visited the local emergency medical center after ingesting 250 ml of organophosphate pesticide. The patient's symptoms improved after the initial intravenous infusion of pralidoxime 5 g and atropine 0.5 mg. However, 18 hours after admission, there was a worsening of the symptoms. A high dose of atropine was administered to improve muscarinic symptoms. A total dose of 5091.4 mg of atropine was used for 30 days, and fever and paralytic ileus appeared as side effects of atropine. Anticholinergic symptoms disappeared only after reducing the atropine dose, and the patient was discharged on the 35th day without any neurologic complications.

• Journal of Environmental Science International
• /
• v.6 no.4
• /
• pp.385-389
• /
• 1997

Pesticide residues were extracted with 70% acetone and transferred to dichloromethane. Extracts were applied to open-column chromatography with florisil and alumina-N. The final extract was analyzed by gas chromatography with electron-capture detector(GC /ECD) and nitrogen-phosphorus detector(GC/NPD). Recoveries of the 17 organochlorine pegticides were ranged from 60.8 to 84.9% and those of 15 organophosphate pesticides, from 70.5% to 100.0%(except phosmet and azlnphos-methyls. The minimum detectable levels of this analytical method were low(0.021-0.058mg/kg).

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.17 no.3
• /
• pp.203-211
• /
• 2007

This study was conducted in cut rose cultivation field in Goyang to evaluate pesticide exposure of farmers and the relationship between the exposure and work environment/method for cut rose farmers. Dermal exposure was assessed with patch (thin chromatography layer paper), cotton glove by body parts during mixing and spraying works in which pyrethroid, organophosphate, carbamate pesticide were used in 4 cut rose greenhouses located in Goyang province, checking characteristics of environment/working method at the same time. Body parts assessed were as follows ; glove : hand, patch : head, neck(front/back), chest, back, shoulder(right/left), upperarm(right/left), forearm(right/left), thigh(right/left), shin(right/left). Pesticides were analyzed using gas chromatography(NPD/FID) after extracting with ethyl acetate. Exposure amount differed according to pesticide type. But after standardizing with total net weight of pesticide sprayed, there were no significant difference among pesticides. There were significant difference in exposure amount among body parts(especially exposure amount of thigh, shin were more than the others), which means exposure happen not by pesticide dispersion in air but by contact with cut rose(leaf, branch) indirectly. Walking forward during spraying made farmers more exposed than waling backward, these results means contacts with leaves/branches made exposure happen in cut rose greenhouse also. As a result, pesticide exposure in cut rose greenhouse was related with contact of leaf/branch which pesticide remained in, which made exposure pattern (especially exposure amount) differ by body parts

• Bulletin of the Korean Chemical Society
• /
• v.35 no.12
• /
• pp.3521-3526
• /
• 2014

A magnetic sonophotocatalyst $Fe_3O_4@SiO_2@TiO_2$ is synthesized for the enhanced biodegradability of organophosphate pesticide. The as-prepared catalysts were characterized using different techniques, such as X-ray diffraction (XRD) and transmission electron microscopy (TEM). The radial sonophotocatalytic activity of $Fe_3O_4@SiO_2@TiO_2$ nanocomposite was investigated, in which commercial dichlorvos (DDVP) was chosen as an object. The degradation efficiency was evaluated in terms of chemical oxygen demand (COD) and enhancement of biodegradability. The effect of different factors, such as reaction time, pH, the added amount of catalyst on $COD_{Cr}$ removal efficiency were investigated. The average $COD_{Cr}$ removal efficiency reached 63.13% after 240 min in 12 L sonophotocatalytic reactor (catalyst $0.2gL^{-1}$, pH 7.3). The synergistic effect occurs in the combined sonolysis and photocatalysis which is proved by the significant improvement in $COD_{Cr}$ removal efficiency compared with that of solo photocatalysis. Under this experimental condition, the $BOD_5/COD_{Cr}$ ratio rose from 0.131 to 0.411, showing a remarkable improvement in biodegradability. These results showed that sonophotocatalysis may be applied as pre-treatment of pesticide wastewater, and then for biological treatment. The synthesized magnetic nanocomposite had good photocatalytic performance and stability, as when it was used for the fifth time, the $COD_{Cr}$ removal efficiency was still about 62.38%.

• Journal of The Korean Society of Clinical Toxicology
• /
• v.4 no.1
• /
• pp.1-6
• /
• 2006

Purpose: Hemoperfusion is an effective modality of extracorporeal elimination of toxins in acutely poisoned patients. We evaluated the effect of hemoperfusion on plasma concentration of toxins in patients exposed to certain pesticides. Methods: Eleven patients who were acutely exposed to pesticides participated in our study. We measured plasma pesticide concentration from the whole blood obtained by arterial and venous sources by gas chromatography. Results: The plasma concentrations of only 3 patients was measured. Methidation clearance by hemoperfusion was 82.2%, fenitrothion was 23%, and endosulfan was 0% Conclusion: Measurement of plasma organophosphate concentration is not a practical application. Our results suggest that hemoperfusion is applicable in patients with pesticide intoxication according to clinical status.

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

• Journal of the Korea Organic Resources Recycling Association
• /
• v.14 no.3
• /
• pp.110-116
• /
• 2006

In this study, the biodegradation rate of paraoxon, that is an organophosphate pesticide, was enhanced by recombinant Escherichia coli harboring organophosphorus hydrolase (OPH). The optimum conditions were 8.5 of initial pH and 5.0% of acetone for the enhancement of specific whole cell OPH activity. When the OPH was produced to 498 Unit/L, 98% of 275mg/L paraoxon was degraded within 10 minutes, and thus the biodegradation rate was enhanced to $29.2mg/g{\cdot}min$. The results implied that practical bioremediation technology developed in this study was an effective method to degrade residual organophosphate pesticide in ground water or soils in a short time.