1.Chlorpyrifos Blood Level and Exposure Symptoms among Paddy Farmers in Sabak Bernam, Malaysia
Rozita Hod ; Azimatun Noor Aizuddin ; Shamsul Azhar Shah ; Mohd Rohaizat Hassan ; Nazarudin Safian ; Mohd Hasni Jaafar
International Journal of Public Health Research 2011;1(1):1-6
The extensive and intensive use of pesticides in agricultural practices has exposed farmers to various hazards resulting in varying degrees of health outcomes. We conducted a cross-sectional study among paddy farmers in Sabak Bernam district, Malaysia. The objective of this study was to gather baseline information on chlorpyrifos blood level and its relationship with pesticides exposure symptoms. We detected chlorpyrifos in farmers’ blood in 7 percent of the respondents, with mean 7.29 nanogram per millilitre blood (sd 5.84 nanogram per millilitre). The percentage of farmers who experienced at least one pesticide exposure symptoms was 75 percent. However, we found no significant association between chlorpyrifos blood level and its exposure symptoms. The farmers had low scores on safe practice of pesticide use even though they have high marks on knowledge and attitude. We found no significant association between the scores on knowledge, attitude and practice on pesticide use and the chlorpyrifos blood level. The presence of pesticide exposure symptoms proved that most of the farmers were exposed to hazardous effects of pesticides. Specific trainings on safe use and handling of pesticides should be given on regular basis to these farmers to ensure they are protected from hazardous effects of pesticides exposure.
Chlorpyrifos
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Pesticides
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Hazardous Substances
2.Resistance and control of cypermethrin and chlorpyrifos as acaricide for control of hard tick Haemaphysalis longicornis (acari: ixodidae).
Korean Journal of Veterinary Research 2014;54(2):117-120
Chemotherapeutic treatment is still the foundation of tick control programs. This study investigated the acaricidal efficacy of cypermethrin alone and in combination with chlorpyrifos against Haemaphysalis (H.) longicornis. Unfed larval ticks were exposed to 0.1, 1.0, and 10 mg/mL cypermethrin for 60 min, after which the acaricidal efficacy was examined based on tick mortality. All compounds showed similar suppression curves, with the best control being achieved by cypermethrin and chlorpyrifos (1 : 1 ratio) at 10 mg/mL. Effective cypermethrin concentrations for tick control were two to seven times higher than the recommended doses, indicating resistance by H. longicornis.
Chlorpyrifos*
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Ixodidae*
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Mortality
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Tick Control
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Ticks
3.The rabbit experimental study for toxicokinetics of chlorpyrifos impacted by hemoperfusion.
Xiang GUO ; Xiao CHEN ; Hongshun ZHANG ; Xin LONG ; Qian HE ; Chengye SUN ; Xianqing HUANG ; Jian HE
Chinese Journal of Industrial Hygiene and Occupational Diseases 2015;33(11):844-846
OBJECTIVETo investigate toxicokinetic parameters impacted by hemoperfusion after oral chlorpyrifos exposure, to investigate the adsorption effect of hemoperhusion for chlorpyrifos poisoning.
METHODS12 rabbits were divided into two groups after oral exposure with chlorpyrifos 300 mg/kg body weight. Control group: without hemoperfusion; hemoperfusion group: hemoperfusion starts 0.5 h after chlorpyrifos exposure and lasts for 2h. Blood samples were collected at different times, concentrations of chlorpyrifos were tested by GC, then, toxicokinetic parameterswere calculated and analysis by DAS3.0.
RESULTSIn hemoperfusion group, peak time was (7.19±3.74) h, peak concentrations was (1.37±0.56) mg/L, clearance rate was (13.93±10.27) L/h/kg, apparent volume of distribution was (418.18±147.15) L/kg The difference of these parameter were statistically significant compared with control group (P<0.05).
CONCLUSIONHmoperfusion will decrease the inner exposure and load dose of rabbits with chlorpyrifos poisoning.
Animals ; Chlorpyrifos ; pharmacokinetics ; toxicity ; Hemoperfusion ; Metabolic Clearance Rate ; Rabbits ; Toxicokinetics
5.Plasma Cholinesterase Activity in the Sprayer Occupationally Exposed to Organic Phosphate Pesticides.
Korean Journal of Preventive Medicine 1983;16(1):51-58
This study was carried out to obtain the basic data for the preverition of chronic poisoning by organic phosphate pesticides. 6 sprayers who participated in the summer pest control programs of Jeonju city were chosen as the subjects in this study. Pesticides which were spread in the period of study are DDVP (1.09%), dursban (1.8%) and dibrom (1.9%). And from May 16, 1983 to Aug. 22, 1983, plasma cholinesterase activity, hematological and biochemical parameters were measured with several physical examinations for each sprayers and controls. Majors findings are as following; 1. Before pesticides were sprayed, plasma cholinesterase were 7.32+/-6 microM/20microliter/hr. in sprayers and 7.13+/-1.39 microM/20 microliter/hr. in the control group(p>0.05). 2. At 60th day of spraying, plasma cholinesterase activity of sprayers was 6.78+/-2.01 microM/20 microliter/hr. Which is significantly decreased from the pre-exposed value(p<0.01), but plasma cholinesterase activity in the control group was not changed. 3. The specific findings which suggested to organophosphorous poisoning were not found through the period of study. 4. Hematological and bichemical parameters were not significantly changed in the both groups.
Chlorpyrifos
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Cholinesterases*
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Dichlorvos
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Jeollabuk-do
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Naled
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Occupations*
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Pest Control
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Pesticides*
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Physical Examination
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Plasma*
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Poisoning
9.Development of a novel high throughput brain-on-chip with 3D structure and its application in evaluation of pesticide-induced-neurotoxicity.
Chenyu ZHAO ; Haidi LI ; Xiaoping CHEN
Chinese Journal of Biotechnology 2021;37(7):2543-2553
We designed and fabricated a novel high throughput brain-on-chip with three dimensional structure with the aim to simulate the in vivo three-dimensional growth environment for brain tissues. The chip consists of a porous filter and 3D brain cell particles, and is loaded into a conventional 96-well plate for use. The filter and the particle molds were fabricated by using computer modeling, 3D printing of positive mold and agarose-PDMS double reversal mold. The 3D cell particles were made by pouring and solidifying a suspension of mouse embryonic brain cells with sodium alginate into a cell particle mold, and then cutting the resulting hydrogel into pieces. The loaded brain-on-chip was used to determine the neurotoxicity of pesticides. The cell particles were exposed to 0, 10, 30, 50, 100 and 200 µmol/L of chlorpyrifos or imidacloprid, separated conveniently from the medium by removing the porous filter after cultivation. Subsequently, cell proliferation, acetylcholinesterase activity and lactate dehydrogenase release were determined for toxicity evaluation. The embryonic brain cells were able to grow and proliferate normally in the hydrogel particles loaded into the filter in a 96-well plate. Pesticide neurotoxicity test showed that both chlorpyrifos and imidacloprid presented dose-dependent inhibition on cell growth and proliferation. Moreover, the pesticides showed inhibition on acetylcholinesterase activity and increase release of lactate dehydrogenase. However, the effect of imidacloprid was significantly weaker than that of chlorpyrifos. In conclusion, a novel brain-on-chip was developed in this study, which can be used to efficiently assess the drug neurotoxicity, pharmacodynamics, and disease mechanism by combining with a microtiterplate reader.
Animals
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Brain
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Chlorpyrifos/toxicity*
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Culture Media
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Mice
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Oligonucleotide Array Sequence Analysis
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Pesticides/toxicity*