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Honey botanical origin is a parameter affecting its market price as certain origins are related to special organoleptic properties or potential health benefits attracting consumers’ attention. However, identifying honey botanical origin is a challenging task commonly requiring extensive high-end analysis. In this study, to address this challenge, a rapid and non-distractive attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) method was developed and special focus was paid on the spectral data pre-processing and its effect on the performance of chemometric models. Twenty-two different pre-processing methods were tested, namely, scatter correction methods, spectral derivation methods and their combinations. In each occasion, both supervised and non-supervised tools were implemented and the cross-validation parameters were used as an indicator on the efficient projection of fifty-one (n = 51) honey samples originating from 5 different botanical origins (blossom, honeydew, cotton, thyme, citrus). Importantly, combining multiplicative scatter correction followed by Savitzky-Golay first derivation is suggested as the most efficient data pre-processing method. Eventually, this data pre-processing was applied in binary models acquiring excellent recognition (87–100%) and prediction (81–100%) ability. In conclusion, the presented method set light on the undermined effect of spectral data pre-processing before the application of advanced chemometrics. © 2023 Elsevier Inc.

Acute intoxication incidents due to neurotoxic organophosphate (OP) insecticides are occasionally reported, related either to suicidal attempts or occupational exposure due to the misuse of protective equipment. Among them, chlorpyrifos is a compound related to great controversy, which is still authorized and easily accessible in many countries around the world. However, to screen for its exposure markers, instrumental methods are commonly applied, which cannot enable rapid monitoring at an early stage of an intoxication. Therefore, in this study, a microfluidic paper-based analytical device (mu PAD) able to rapidly screen for chlorpyrifos-oxon, the toxic chlorpyrifos metabolite, in human serum was developed and fully validated. The mu PAD combines wax-printed butyrylcholinesterase (BChE) paper sensors, a lab-on-a-chip (LOC) prototype injector and a smartphone as the analytical detector. In principle, the wax-printed strips with adsorbed BChE are embedded into LOC injectors able to deliver samples and reagents on-demand. A smartphone reader was used to monitor the color development on the strips providing binary qualitative results. mu PAD method performance characteristics were thoroughly evaluated in terms of specificity, detection capability (CC beta) and ruggedness. The developed analytical platform is rapid (results within 10 min), cost-efficient (0.70 (sic)), potentially applicable at the point-of-need and attained a low CC beta (10 mu g L-1 in human serum). Finally, mu PAD characteristics were critically compared to wellestablished methods, namely an in-house BChE microplate assay and liquid chromatography tandem mass spectrometry., Funding Agencies|European Unions Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grantEuropean Union (EU) [720325]; METROFOOD-CZ research infrastructure project (MEYS Grant) [LM2018100]; [A2_FPBT_2020_013]

Due to disease outbreaks associated with contaminated vegetables it has been speculated to what extent this may be linked with application of animal manure as fertilizer, which is particularly practiced in organic vegetable production where conventional fertilizers are prohibited. A field survey was therefore performed to assess the survival and transfer of antibiotic-resistant E. coli from animal manure to lettuces, with E. coli serving as an indicator of bacterial enteric pathogens. Animal slurry was applied to 3 Danish fields prior to planting of lettuce seedlings, then 5-8 weeks later at the normal time of harvest, inner and outer leafs of 10 lettuce heads were pooled into one sample unit with a total of 50 pools per field. Additionally, in one field, 15 soil samples were collected weekly until the harvest time. E. coli was enumerated by plating 1 mL of 10-fold serial dilutions of 5 g of homogenized sample material, i.e. manure, soil and lettuce onto PetrifilmTM Select E. coli count plates (3M) containing 16 mg/L streptomycin or 16 mg/L ampicilin or no antibiotics. Plates were then incubated 24 h at 44°C. Selected isolates of E. coli (n=83) from slurry, soil and lettuce were analysed by PFGE DNA typing for further discrimination. The slurry applied to the fields contained 3.0-4.5 Log10 E. coli CFU/g and resistant E. coli ranged from 1.0 to 4.4 Log10 E. coli CFU/g with particular high numbers of streptomycin resistant E. coli in conventional pig slurry (field 1) opposed to organic cow slurry (field 2 and 3). E. coli was found in 36-54% of the pooled lettuce samples at the three fields with a detection limit of 10 CFU/g and 10-18% and 0-2% of pools had streptomycin and ampicilin resistant E. coli, respectively. Unexpectedly, the highest percentage of lettuce pools with antibiotic resistant E. coli were found on fields fertilized with organic cow slurry where 0.1-5% of E. coli was resistant opposed to 5-50% resistant E. coli in conventional slurry. Numbers of E. co

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The gas phase polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs in the atmosphere of five European countries (Austria, the Czech Republic, Poland, Slovakia and Sweden) were measured simultaneously during two 21-day passive sampling campaigns using semipermeable membrane devices (SPMDs). SPMD samplers, consisting of a pair of SPMDs covered by a metal umbrella, were deployed at 40 locations ranging from remote and rural to urban and industrial, at a similar time during each of the two sampling campaigns (autumn 1999, except in Poland, winter 1999, and summer 2000). The total amounts of PAHs and nitro-PAHs found in the SPMDs ranged between 5.0–1.2×103 and 1.1×10−3–4.0 ng SPMD−1 day−1, respectively. The measured environmental sampling conditions were similar between sites and, thus, the variations in the SPMD data reflected the spatial differences in gas phase concentrations of nitro-PAHs and PAHs within and between countries. The gas phase concentrations of nitro-PAHs and PAHs found in East Europe (Slovakia, the Czech Republic and Poland 1999) were 10 times higher than those measured in Sweden, Austria and Poland in 2000. In each country, the levels of PAHs and nitro-PAHs differed by one–three orders of magnitudes amongst sampling sites. The highest within-country spatial differences were found in Poland where levels of PAHs and nitro-PAHs were about one and two orders of magnitudes, respectively, higher in winter 1999 than in summer 2000, probably due to increasing emissions of coal combustion for residential heating. Differences in PAH-patterns between sites were visualized by the multivariate projection method, principal component analysis (PCA). However, no specific source patterns were found, probably since imissions rather than emissions were measured, so the PAHs detected at many sites originated from multiple sources.