Did you mean: profenofos
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Food Chemistry Sep 2017The present work describes a novel HPLC and UV-spectrophotometric method for the simultaneous estimation of chlorpyrifos and prophenofos in vegetables and fruits. In UV...
The present work describes a novel HPLC and UV-spectrophotometric method for the simultaneous estimation of chlorpyrifos and prophenofos in vegetables and fruits. In UV method, the absorbance of chlorpyrifos and prophenofos was measured at wavelength 277nm and 289nm respectively and quantitation was carried out by first order derivative method. The calibration curve for chlorpyriphos and prophenofos was found to be linear in the range of 6-16μg/mL with correlation coefficient 0.9979 and 0.9993 respectively. The HPLC separation was achieved on Hibar C column (250×4.6mm, 5µ) using mobile phase consist of acetonitrile: water (90:10, v/v) at flow rate 1.0mL/min and the eluent was monitored at 219nm. Pesticides were extracted from the samples by solid phase extraction and liquid-liquid extraction before the analysis. Out of these two extraction methods, solid phase extraction was found more efficient in terms of % recovery as compared to liquid-liquid extraction. The developed method was applied for estimation of chlorpyrifos and prophenofos and it was found that the chlorpyrifos was 0.018mg/kg, which is above maximum residue limits (0.01mg/kg), which might be toxic to body. Prophenofos was not found in any collected samples of vegetables and fruits.
Topics: Chromatography, High Pressure Liquid; Liquid-Liquid Extraction; Organophosphorus Compounds; Pesticides; Solid Phase Extraction; Spectrophotometry
PubMed: 28407934
DOI: 10.1016/j.foodchem.2017.03.083 -
Journal of Economic Entomology Jun 2000The effect of insecticides on Trichogramma exiguum Pinto & Platner emergence, adult survival, and fitness parameters was investigated. Insecticides tested were lambda...
The effect of insecticides on Trichogramma exiguum Pinto & Platner emergence, adult survival, and fitness parameters was investigated. Insecticides tested were lambda cyhalothrin, cypermethrin, thiodicarb, profenophos, spinosad, methoxyfenozide, and tebufenozide. All insecticides, with the exception of methoxyfenozide and tebufenozide, adversely affected Trichogramma emergence from Helicoverpa zea (Boddie) host eggs when exposed at different preimaginal stages of development (larval, prepupal, or pupal). Regardless of the developmental stage treated, none of the insecticides tested had a significant effect on the sex ratio or frequency of brachyptery of emerged females. However, the mean life span of emerged T. exiguum females significantly varied among insecticide treatments, and was significantly affected by the developmental stage of parasitoid when treated. Based on LC50 values, spinosad and prophenofos were the most toxic compounds to female T. exiguum adults, followed by lambda cyhalothrin, cypermethrin, and thiodicarb. Insecticides field-weathered for four to 6 d on cotton leaves showed no activity against female T. exiguum adults.
Topics: Animals; Biological Assay; Female; Hydrazines; Insecticides; Juvenile Hormones; Moths; Nitriles; Pyrethrins; Thiocarbamates; Wasps
PubMed: 10902302
DOI: 10.1603/0022-0493-93.3.577 -
Journal of AOAC International 1999The twin-island state of Trinidad and Tobago produces much of the fresh fruit and vegetables consumed locally, although some are exported to Europe and North America. On...
The twin-island state of Trinidad and Tobago produces much of the fresh fruit and vegetables consumed locally, although some are exported to Europe and North America. On average, approximately 1500 tons of pesticides are imported annually, of which about 10-15% are organophosphates. A survey of local farmers revealed that a wide range of pesticides are used and that the same pesticides are used on several crops to control different pests. Application rates exceeding manufacturers' recommendations are also common, as is the disregard of recommended preharvest intervals after pesticide application. Praedial larceny and subsequent sale of freshly sprayed crops also contribute to the risks posed to consumers by pesticide residues. A market basket survey of produce conducted between October 1996 and May 1997 in Trinidad for organophosphate pesticides showed that 10% of produce exceeded the internationally acceptable maximum residue limits (MRLs) for the respective pesticides. Celery constituted 6.5% of all such samples, with over 83% of celery samples exceeding the MRL. Organophosphate pesticides detected were methamidophos, triazophos, prophenofos, diazinon, ethion, pirimiphos methyl, malathion, and dimethoate, with the first 4 being the most commonly detected. There is an urgent need for comprehensive monitoring and control of pesticides on produce by local regulatory agencies, especially because the above data relate only to one class of pesticides. The education of farmers on safe operating practices regarding pesticide application and observation of recommended preharvest intervals for applied pesticides is also required.
Topics: Chromatography, Gas; Food Contamination; Gas Chromatography-Mass Spectrometry; Insecticides; Organophosphorus Compounds; Pesticide Residues; Trinidad and Tobago; Vegetables
PubMed: 10444836
DOI: No ID Found