Insecticides of neonicotinoides class: determining exposure via workers' urine.

For biomonitoring of exposure in workers with insectocaricides, the authors created a method of multi-component assessment oflowlevels of neonicotinomides in workers' urine, based on last generation tandem liquid mass-spectrometry (triple quadrupole) with ionization source - electrostatic dispersion (positive ionization) in dynamic multi-reaction monitoring with two transitions of parent ions (for quantitative assessment and ionic ratio confirmation). After the work, the operators gave urine samples (about 100 ml in average) that were frozen and kept under -20°C before analysis. Samples were defrozen before analysis, and each urine portion of 5 ml was diluted by equal volume of 0,1% formic acid. To extract substances out of the samples, solid-phase extraction (cartridges based on octadecylsilane) was applied, elution was performed with 1 ml of methanol. Lower limit of the substances detection in urine - 0,02-0,05 ng/ml, lower limit of the quantitative assessment - 0,1-0,2 ng/ml. The method was tested on monitoring of the workers' exposure to preparations based on imidaclopride and clotianidine in natural conditions of pesticides use in agriculture with various processing technologies. midacloprid was identified in urine of 3 professional operators after wheat and oat seeds treatment and after subsequent seeding at lower limit of detection (0,02 ng/ml), lower limit of quantitative assessment (0,1 ng/ ml) and 0,34 ng/ml.

Biomonitoring and exposure levels of imidacloprid in air of workplace and on skin of workers exposed to pesticides.

The article presents results ofhygienic studies on work conditions in using imidacloprid-based pesticides in agriculture. Analysis covered imidacloprid levels in air of workplace, on skin and in urine of workers.

[Determination of polioksin B in the air environment and in washouts from skin of operators by HPLC].

Polyoxin B being an effective inhibitor of synthesis of chitin of the cell wall of many phytopathogenic fungi, is recommended as a fungicide for control of phytopathogenic organisms that cause damage to crop. For the determination of the exposure of employees working with pesticides there was developed the method of the measurement of concentrations of polyoxin B in air of working area, atmospheric air of populated areas and washouts from the operators ' integuments, based on high performance liquid chromatography with ultraviolet detector (detection wavelength of270 nm), including sampling air environment in the sorption tube ORBO-44, filled with sorbent XAD-2, extraction of the sorbent with polyoxin by a mixture of carbinol-water (in a ratio of 95:5,on volume), washout from the surface of the skin with ethyl alcohol by way of washing, concentrating, quantitative chromatographic analysis. Lower limits of the quantification ofpolyoxin B in the air ofworking area - 0.2 mg/m at the aspiration of 2 dm of air, atmospheric air - 0.016 mg/m at the aspiration of 25 dm of air, in washouts from the operators' integuments - 0.4 pg/wash, the linear range of the defined concentrations accounted for of 0.2 - 2.4 pg/cm, the total error of measurement of the concentrations of polyoxin B in air is 17%; in washouts from the operators' integuments - 16%. The developed method was approbated for the determination of polyoxin in samples of air of working zone, atmospheric air within the sanitary gap, washouts from the operators ' integuments and air drift samples taken under processing of roses in the hothouse and in the monitoring of the phytosanitary condition of the plants every other day after treatment.