Multiclass/multiresidue method for monitoring widely applied plant protecting agents in air during field dispersion work

Comprehensive study of insecticides in atmospheric particulate matter in Hanoi, Vietnam: Occurrences and human risk assessment

Air pollution is the most serious environmental issue in Vietnam, particularly in big cities. Air pollutants that are set as environmental standards are regularly monitored by the public institutions. Whereas, environmental data on organic micro-pollutants in atmospheric particulate matters (APMs) is limited, including PAHs and POPs. Although massive pesticides are used in big cities, their data in APMs in Vietnam is very scarce. In order to elucidate their occurrence in the ambient air in Hanoi and their health effects, we surveyed 107 insecticides in APMs by a novel target screening method using LC-QTOF-MS-SWATH. A total of 19 insecticides were detected in the dry and the rainy seasons. Among them, 16 substances are, to our knowledge, reported for the first time in the literature. Their total concentrations varied from 0.47 to 27.0 ng m^-3 (median, 3.6 ng m^-3), detection frequencies of 12 compounds are higher than 42%, and the number of insecticides detected per each sample ranging from 5 to 13 (median, 9). Total concentrations in the dry season were generally higher than in the rainy season, and concentrations at night were higher than daytime in both seasons. The level of insecticides depends not only on the season, but also on its physicochemical properties, its application conditions, and the meteorological conditions. Their emission sources could be related to agricultural usage, floricultural activities, and pest control in houses. The total maximum daily intake (DI_air) through inhalation for adults and children were 2.39E-05 mg kg^-1 d^-1 and 2.98E-05 mg kg^-1 d^-1, respectively. The highest Hazard Quotients (HQs) were 1.34E-03 and 3.37E-03, and the highest Hazard Indices (HIs) were 2.71E-03 and 6.33E-03 for adults and children, respectively. All values of HQs, and HIs of insecticides were less than 1, indicating that health risk would be negligible.

Simultaneous residue measurement of pendimethalin, isopropalin, and butralin in tobacco using high-performance liquid chromatography with ultraviolet detection and electrospray ionization/mass spectrometric identification

A simultaneous residue analysis of pendimethalin, isopropalin, and butralin in tobacco was developed with high-performance liquid chromatography with ultraviolet monitoring and electrospray ionization mass spectrometry (HPLC-UV-ESI/MS). The herbicide residues of pendimethalin, isopropalin, and butralin in tobaccos were extracted by ultrasonication with ethyl acetate, followed by a cleanup procedure with gel permeation chromatography. The three herbicides were separated within 15 min using a LiChrosorb 18 column with methanol-10 mmol/L ammonium acetate (85:15, v/v) as the eluent. The limits of quantitation, using HPLC-UV, were ca. 0.05, 0.08, and 0.06 mg/kg for pendimethalin, isopropalin, and butralin, respectively, whereas the overall recoveries ranged from 77.5 to 91.8%. The proposed method has been successfully applied to measure 300 real samples, and the residue profiles of three herbicides in tobacco samples were obtained and evaluated.

Assessment of potential (inhalation and dermal) and actual exposure to acetamiprid by greenhouse applicators using liquid chromatography–tandem mass spectrometry

New analytical methods based on liquid chromatography with electrospray tandem mass spectrometry (LC-MS/MS) have been developed and validated for assessing the exposure of greenhouse workers to acetamiprid. Both ambient (potential inhalation and dermal exposure) and internal dose (biological monitoring of urine samples) measurements were carried out. Potential inhalation exposure was assessed using Chromosorb 102 cartridges connected to air personal samplers. Potential dermal exposure was estimated by using whole body dosimetry. The measurement of actual exposure was done by analyzing the parent compound in urine samples of the applicators, after a solid-phase extraction (SPE) step. The methods showed a good accuracy (72-92%), precision (2-13%) and lower limits (few microg l(-1)). The validated approaches have been applied to assess potential and actual exposure of agricultural workers spraying acetamiprid in greenhouses. The results shown the need to wear personal protective equipment (suits) in order to reduce the absorbed dose of acetamiprid.