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International audience ; Different techniques for the determination of total tin in beverage and canned food by atomic spectrometry were compared. The performance characteristics of Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Hydride Generation Inductively Coupled Plasma Atomic Emission Spectrometry (HG-ICP-AES), Electrothermal Atomization Atomic Absorption Spectrometry (ETA-AAS) and Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) were determined in term of linearity, precision, recovery, limit of detection, decision limit (CCα) and detection capability (CCβ) (Decision 2002/657/EC). Calibration ranges were covered from ng/L to mg/L level. Limits of detection ranged from 0.01; 0.05; 2.0; 200 µg/L were respectively reached for ICP-MS; HG-ICP-AES; ETA-AAS and ICP-AES. Precision, calculated according to ISO 5725-2 for repeatability and within lab-reproducibility and expressed as relative standard deviation (RSD), ranges from 1.6 to 4.9% and recovery, based on the decision 2002/657/EC, was found between 95 to 110%. Procedures for the mineralization or extraction of total tin were compared. Wet digestion, sequentially, with nitric acid and hydrogen peroxide provided the best results. The influence of possible interferences present in canned food and in beverage was studied and no interference on the determination of tin was observed. Since maximum levels for tin established by the European legislation vary from 50 mg/kg in canned baby foods, infant food to 200 mg/kg in canned food, ICP-AES was chosen as the preferred technique for routine analysis thanks to its good precision, reliability and easy to use. The accuracy of this routine method was confirmed by participating in 6 proficiency test schemes with z-scores ranging from -1.9 to 0.6. Several canned foodstuffs and beverage samples from local market were analysed with this technique.

International audience ; Different techniques for the determination of total tin in beverage and canned food by atomic spectrometry were compared. The performance characteristics of Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Hydride Generation Inductively Coupled Plasma Atomic Emission Spectrometry (HG-ICP-AES), Electrothermal Atomization Atomic Absorption Spectrometry (ETA-AAS) and Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) were determined in term of linearity, precision, recovery, limit of detection, decision limit (CCα) and detection capability (CCβ) (Decision 2002/657/EC). Calibration ranges were covered from ng/L to mg/L level. Limits of detection ranged from 0.01; 0.05; 2.0; 200 µg/L were respectively reached for ICP-MS; HG-ICP-AES; ETA-AAS and ICP-AES. Precision, calculated according to ISO 5725-2 for repeatability and within lab-reproducibility and expressed as relative standard deviation (RSD), ranges from 1.6 to 4.9% and recovery, based on the decision 2002/657/EC, was found between 95 to 110%. Procedures for the mineralization or extraction of total tin were compared. Wet digestion, sequentially, with nitric acid and hydrogen peroxide provided the best results. The influence of possible interferences present in canned food and in beverage was studied and no interference on the determination of tin was observed. Since maximum levels for tin established by the European legislation vary from 50 mg/kg in canned baby foods, infant food to 200 mg/kg in canned food, ICP-AES was chosen as the preferred technique for routine analysis thanks to its good precision, reliability and easy to use. The accuracy of this routine method was confirmed by participating in 6 proficiency test schemes with z-scores ranging from -1.9 to 0.6. Several canned foodstuffs and beverage samples from local market were analysed with this technique.

In the present study the analysis of the physico-chemical parameters of the collected TWW shows the BOD, COD, COT, Cl-, NO3, NO2, suspended matter, organic matter, turbidity and conductivity were in accordance with the required Tunisian legislations. In the same occurrence, the ICP-MS and the UPLC-MS/MS analysis show that TWW were devoid of different toxic metals and antibiotics, respectively. We opted to reuse of the TWW in the irrigation of young olive trees of two varieties: Olea europaea L. cv. Chetoui and Olea europaea L. cv. Chemlali which receiving 1 L/week of TWW during five months. Results show that dry roots weight and the content of chlorophyll a in 'Chetoui' variety increased significantly (p < 0.05) when compared to the control group. On the same way, significantly increase of leaf area, dry roots and leaves weights was observed in 'Chemlali' variety treated with TWW. Keywords: Dairy wastewater, Reuse wastewater, Olea europaea L., ICP-MS, UPLC-MS/MS

This work presents a strategy for elucidation of unknown migrants from plastic food contact materials (baby bottles) using a combination of analytical techniques in an untargeted approach. First, gas chromatography (GC) coupled to mass spectrometry (MS) in electron ionisation mode was used to identify migrants through spectral library matching. When no acceptable match was obtained, a second analysis by GC-(electron ionisation) high resolution mass spectrometry time of flight (TOF) was applied to obtain accurate mass fragmentation spectra and isotopic patterns. Databases were then searched to find a possible elemental composition for the unknown compounds. Finally, a GC hybrid quadrupole-TOF-MS with an atmospheric pressure chemical ionisation source was used to obtain the molecular ion or the protonated molecule. Accurate mass data also provided additional information on the fragmentation behaviour as two acquisition functions with different collision energies were available (MSE approach). In the low-energy function, limited fragmentation took place, whereas for the high-energy function, fragmentation was enhanced. For less volatile unknowns, ultra-high pressure liquid chromatography-quadrupole-TOF-MS was additionally applied. Using a home-made database containing common migrating compounds and plastic additives, tentative identification was made for several positive findings based on accurate mass of the (de)protonated molecule, product ion fragments and characteristic isotopic ions. Six illustrative examples are shown to demonstrate the modus operandi and the difficulties encountered during identification. The combination of these techniques was proven to be a powerful tool for the elucidation of unknown migrating compounds from plastic baby bottles. ; Federal Government Service for Public Health of Belgium through project: ALTPOLYCARB Generalitat Valenciana (Group of Excellence Prometeo) II/2014/023 ; ISIC/2012/016 Envi-Food

Background: The consumption of energy drinks (EDs) is increasing in the general population, but little is known about the consumption of EDs among pupils in Africa. This study was designed to assess the consumption of EDs among pupils between 10 and 17 years of age and to assess average caffeine concentrations contained in EDs sold in Lubumbashi. Methods: We conducted a cross-sectional survey in five schools using a standardised questionnaire taken face-to-face. Samples of locally purchased EDs were analysed by High Performance Liquid Chromatography with Ultra-Violet spectrometry (HPLC-UV). Results: Of 338 pupils (54% girls), 63% reported having consumed at least one ED in the last week and 34% drank at least one ED a day. The cheapest ED was the most widely consumed. Among pupils having consumed at least one ED in the last week, 79% reported consuming it for refreshment and 15% to get energy. For those who reported not consuming EDs, 40% reported that their parents or teachers forbade them to drink EDs. Some (14%) teenagers, mainly boys, mixed ED with alcohol. The concentrations of caffeine measured in twelve brands of EDs ranged from 7.6 to 29.4 mg/100 mL (median 23.3), giving caffeine contents of 37.5 to 160 mg (median 90 mg) per can or bottle. The estimated daily intake of caffeine through EDs was between 51.3 mg and 441.3 mg among those consuming EDs regularly. Conclusion: Our study convincingly demonstrates that caffeine-containing EDs are not only consumed by youngsters living in affluent societies. We documented widespread regular consumption of EDs among (pre-)adolescent schoolchildren living in Lubumbashi, a large city of the Democratic Republic of Congo (DRC). In view of the global market expansion of caffeinated EDs, it is reasonable to suspect that similar surveys in other urban areas of sub-Saharan Africa would yield similar findings. Pricing and advertising regulations and education on EDs are necessary to limit the regular consumption of EDs among adolescents.