Simultaneous determination of dechloranes, polybrominated diphenyl ethers and novel brominated flame retardants in food and serum

A sensitive method for the simultaneous quantification of dechloranes, polybrominated diphenyl ethers (PBDEs) and novel brominated flame retardants (NBFRs) has been developed for gas chromatography (GC) coupled to tandem mass spectrometry operating in electron capture negative ionization (ECNI) mode. The major advance has been achieved by combining selected ion monitoring (SIM) and multiple reaction monitoring (MRM) modes in well-defined time windows, to determine dechloranes, PBDEs and NBFRs at picogram per gram level in one single analysis in complex matrix biological samples. From the chromatographic point of view, efforts were devoted to study several injection modes using multimode inlet (MMI) in order to obtain low instrumental detection limits, necessary for trace compounds such as Dechlorane Plus (DP) isomers. Method performance was also evaluated: calibration curves were linear from 20 fg μL−1 to 100 pg μL−1 for the studied compounds, with method detection limits at levels of 50 fg g−1 for DPs. Repeatability and reproducibility, expressed as relative standard deviation, were better than 5% even in solvent vent mode for the injection of standards. The application to a wide range of complex samples (including food, human and animal serum samples) indicated a sensitive and reliable way to quantify at the picogram per gram level 4 halogenated norbornenes (HNs), Dechlorane Plus (anti-DP and syn-DP) and 2 of their homologues (Dechlorane-602 and Dechlorane-603), 11 PBDE congeners (no. 28, 47, 49, 66, 85, 99, 100, 153, 154, 183 and 209) and 5 novel BFRs, i.e. decabromodiphenyl ethane (DBDPE), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), hexabromobenzene (HBB), 2,3,4,5-tetrabromo-ethylhexyl-benzoate (TBB) and tetrabromophthalate (TBPH).The authors acknowledge the financial support of Universitat Jaume I (UJI-A2016-01) and Generalitat Valenciana (research group of excellence PROMETEO/2009/054 and PROMETEO II 2014/023 and Collaborative Research on Environment and Food-Safety (ISIC/2012/016)). Carlos Sales acknowledges the COST Action ES1307 for the STSM grant which made possible his stay at the Toxicological Centre of Antwerp. Dr. Giulia Poma and Dr. Govindan Malarvannan acknowledge the University of Antwerp for their postdoctoral fellowships

Contaminanti nello zooplancton

Not availableContaminanti nello zooplancton nell\u27ambito del progetto di ricerca "Indagini su DDT e sostanze pericolose nell\u27ecosistema del Lago Maggiore"

Black carbon particles in human breast milk: assessing infant’s exposure

Background/AimHuman breast milk is the recommended source of nutrition for infants due to its complex composition and numerous benefits, including a decline in infection rates in childhood and a lower risk of obesity. Hence, it is crucial that environmental pollutants in human breast milk are minimized. Exposure to black carbon (BC) particles has adverse effects on health; therefore, this pilot study investigates the presence of these particles in human breast milk.MethodsBC particles from ambient exposure were measured in eight human breast milk samples using a white light generation under femtosecond illumination. The carbonaceous nature of the particles was confirmed with BC fingerprinting. Ambient air pollution exposures (PM2.5, PM10, and NO2) were estimated using a spatial interpolation model based on the maternal residential address. Spearman rank correlation coefficients were obtained to assess the association between human breast milk’s BC load and ambient air pollution exposure.ResultsBC particles were found in all human breast milk samples. BC loads in human breast milk were strongly and positively correlated with recent (i.e., 1 week) maternal residential NO2 (r = 0.79; p = 0.02) exposure and medium-term (i.e., 1 month) PM2.5 (r = 0.83; p = 0.02) and PM10 (r = 0.93; p = 0.002) exposure.ConclusionFor the first time, we showed the presence of BC particles in human breast milk and found a robust association with ambient air pollution concentrations. Our findings present a pioneering insight into a novel pathway through which combustion-derived air pollution particles can permeate the delicate system of infants

Method validation and comparison of quantification strategies for analysis of chlorinated paraffins in indoor dust by liquid chromatography and high-resolution mass spectrometry

This paper describes the validation of a method for the simultaneous analysis of short-, medium-, and long-chained chlorinated paraffins (SCCPs, MCCPs, and LCCPs, respectively) in indoor dust by ultrasonic extraction and liquid chromatography quadrupole time-of-flight high-resolution mass spectrometry (LC-QTOF-HRMS). A series of spike and recovery experiments (n = 54) were conducted using CPs with varying carbon-chain lengths, chlorination degree, and concentrations. Technical standard mixtures of the SCCPs, MCCPs, and LCCPs were used to quantify spiking experiments by two commonly used calibration procedures: pattern deconvolution and chlorine-content calibration. The results quantified by pattern deconvolution meet the acceptability limits of the European Union Reference Laboratory (EURL) for all tests with trueness ranging from 72% to 141% and good precision represented by coefficients of variation (CVs) less than 15% in all experiments. The chlorine-content calibration also performed well overall, but on average overestimated concentrations for SCCPs and MCCPs by 32% and 25%, respectively, and did not meet the EURL’s trueness limits in all cases. CVs were below 18% for all results derived from the chlorine-content quantification. The final method was successfully applied to indoor dust samples from offices (n = 4), homes (n = 3), and a vehicle (n = 1) from Melbourne, Australia, with SCCPs (C10-13), MCCPs (C14-17), and LCCPs (C18-20) detected in all samples, up to 100, 240 and 190 μg/g, respectively. A preliminary human exposure assessment suggested that CP intake via dust may constitute a major pathway of exposure for populations in Melbourne, Australia