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The diffusion and the recycling of electric and electronic equipment waste (WEEE) are an important issue for industrialised countries. During treatment operations of this equipment, legacy and emerging halogenated flame retardant can be released in the environment, causing great concern for their toxicity. For this purpose, a method to simultaneously determine polybrominated biphenyl ethers, hexabromocyclododecane, 10 emerging brominated flame retardants and in parallel-polychlorinated biphenyls was optimised and applied to particulate matter samples collected within a WEEE facility. In this paper, starting from a previously published method, we drastically simplified the sample preparation, reducing the overall completion time, solvent consumption, costs and achieving adequate selectivity and sensitivity for all the target compounds. The multi–analyte method was evaluated in terms of reproducibility, linearity, recovery, limits of detection, limit of quantification, and matrix effect and compared to the previous method. Quantitative analyses were carried out by gas chromatography-mass spectrometry in negative chemical ionisation, using matrix-matched calibration curves. The reliability and robustness of the method were demonstrated through the analysis of certified and reference compounds in Standard Reference Material 2585. The most abundant compounds in particulate matter samples, collected in an electric and electronic equipment waste treatment plant, were BDE 47 (3.9 ng m−3), CB 138 (2.7 ng m−3), and 1,2-bis(2,4,6-tribromophenoxy) ethane (4.2 ng m−3). [ABSTRACT FROM AUTHOR]

Potential harmful effects of pesticides include risks to human health of workers involved in the wet spray application in cultivated areas. Inhalation exposure depends on several factors including pesticide concentrations in the respirable fraction of airborne particulate matter (PM4). To ensure a high level of protection, the use of tractors with cabins provides protection against dust, aerosols, and vapors. Since tractors not providing maximum protection are still in use, PM4 was sampled during spreading operations in agricultural fields inside and outside tractor cabins. Sample preparation technique based on accelerated solvent extraction and solid-phase extraction cleanup was optimized before analysis of nine pesticides in PM4. Meptyldinocap, deltamethrin, myclobutanil, fluopyram, methoxyfenozide, dimethomorph, fluopicolide, cyflufenamid, and metrafenone were simultaneously determined by high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (HPLC–ESI–MS–MS). The results demonstrated the efficacy of the tractor cabs used in the sampling sites. [ABSTRACT FROM AUTHOR]

Abstract: A quick and reproducible screening analytical method for the simultaneous determination of algal toxins, belonging to different chemical classes, was developed to provide a toxin profile in seawater, useful to assess potential risks to environment and human health. The target compounds were: gonyautoxin-1,4, gonyautoxin-2,3, decarbamoylgonyautoxin-2,3, N‐sulfocarbamoyl-gonyautoxin-1,2, neosaxitoxin, decarbamoyl-neosaxitoxin, saxitoxin, decarbamoyl-saxitoxin, domoic acid, 13-desmethyl spirolide C (SPX1), palytoxin and okadaic acid. Extraction and clean-up were carried out with a combination of Bond Elut LRC-C18 and Carbograph4 cartridges connected in series. Analyte separation was performed in gradient elution mode in 12 min with a Gemini C18 column. Compound detection was carried out in multiple reaction monitoring and in positive ionization mode for paralytic shellfish poisoning toxins, domoic acid, SPX1 and palytoxin, and in negative ionization mode for okadaic acid. The toxins were quantified with matrix-matched calibration curves constructed by spiked seawater samples (concentration levels 0.02–2 μg L−1 depending on the compound). The method was reproducible with intra-day and inter-day relative standard deviations ranging from 4 to 9% and from 8 to 16%, respectively. Good recoveries (84–105%) and good accuracy (2–20%) were obtained by spiking experiments. Limits of detection were calculated for each toxin and varied from 0.011 to 0.12 μg L−1 depending on the compound. The developed method was applied to cultured Ostreopsis cf. ovata samples. The proposed procedure may be considered a valuable alternative to existing methods for monitoring toxic microalgae, since it offers a rapid screening of target toxins, reduced organic solvent consumption, and handling of smaller sample volumes while providing good sensitivity and accuracy.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Airborne bacteria are components of the atmospheric aerosol particles and can be responsible of allergic disease, regardless of their viability. In this paper, we report a method for the determination of total (viable and nonviable) bacterial content in airborne particles, using muramic and dipicolinic acids as biomarkers of bacteria and bacterial spores, respectively. The analytical procedure was optimized with bacteria and spores of Bacillus subtilis. After extraction and purification, the two biomarkers were analyzed by HPLC-ESI-MS/MS and their percentage was evaluated to be used as conversion factor. The present method for the determination of the total bacterial content was then applied to environmental samples, after a proper collection in an urban site. Thanks to the use of a low pressure impactor, capable of fractionating particles into the range of 0.03-10 μm, it was also possible to study the bacterial content in ultrafine, fine, and coarse particulate matter. The results from this study showed that muramic and dipicolinic acids can be determined together in one chromatographic run in reversed phase ion pair chromatography. Bacteria were more abundant than bacterial spores in the urban atmosphere, both showing a higher concentration in the coarse fraction of particles, although bacteria and bacterial spore amounts per unit mass of ultrafine particles were higher than in fine and coarse particles. [ABSTRACT FROM AUTHOR]