Detection of Bromochloro Alkanes in Indoor Dust Using a Novel CP-Seeker Data Integration Tool.

Bromochloro alkanes (BCAs) have been manufactured for use as flame retardants for decades, and preliminary environmental risk screening suggests they are likely to behave similarly to polychlorinated alkanes (PCAs), subclasses of which are restricted as Stockholm Convention Persistent Organic Pollutants (POPs). BCAs have rarely been studied in the environment, although some evidence suggests they may migrate from treated-consumer materials into indoor dust, resulting in human exposure via inadvertent ingestion. In this study, BCA-C14 mixture standards were synthesized and used to validate an analytical method. This method relies on chloride-enhanced liquid chromatography-electrospray ionization-Orbitrap-high resolution mass spectrometry (LC-ESI-Orbitrap-HRMS) and a novel CP-Seeker integration software package for homologue detection and integration. Dust sample preparation via ultrasonic extraction, acidified silica cleanup, and fractionation on neutral silica cartridges was found to be suitable for BCAs, with absolute recovery of individual homologues averaging 66 to 78% and coefficients of variation ≤10% in replicated spiking experiments (n = 3). In addition, a total of 59 indoor dust samples from six countries, including Australia (n = 10), Belgium (n = 10), Colombia (n = 10), Japan (n = 10), Thailand (n = 10), and the United States of America (n = 9), were analyzed for BCAs. BCAs were detected in seven samples from the U.S.A., with carbon chain lengths of C8, C10, C12, C14, C16, C18, C24 to C28, C30 and C31 observed overall, though not detected in samples from any other countries. Bromine numbers of detected homologues in the indoor dust samples ranged Br1-4 as well as Br7, while chlorine numbers ranged Cl2-11. BCA-C18 was the most frequently detected, observed in each of the U.S.A. samples, while the most prevalent degrees of halogenation were homologues of Br2 and Cl4-5. Broad estimations of BCA concentrations in the dust samples indicated that levels may approach those of other flame retardants in at least some instances. These findings suggest that development of quantification strategies and further investigation of environmental occurrence and health implications are needed.

Polychlorinated Naphthalenes in Foods from the French Market: Occurrence, Dietary Exposure, and Evaluation of Relative Contributions to Dioxin-like Contaminants.

Despite the growing interest in PCNs and the dioxin-like toxicity exhibited by a number of congeners, a comprehensive assessment of their contribution to the cocktail of dioxin-like contaminants is still lacking. To address such a shortcoming, this study investigated the PCN contamination in foodstuffs recently acquired in France, together with that of the regulatory polychlorinated dibenzodioxins/furans (PCDD/Fs) and polychlorinated biphenyls (PCBs). PCNs were ubiquitous at levels (∑70 PCNs = 2.5-150 pg g-1 wet weight) similar to those reported in other countries, with maximum concentrations observed in fish and fishery products from the North-East Atlantic Ocean. Their congener patterns further suggested unintentional releases of PCNs, while those of the other foodstuffs were correlated to the historical PCN profiles. Low risk from dietary exposure was estimated (∑70 PCNs-EDIs of 60-360 pg kg-1 bw d-1, ∑24 PCNs-TEQ-EDIs of 8 × 10-3-2.2 × 10-2 pg TEQ kg-1 bw d-1), with milk and dairy products being the highest contributors, followed by meat and meat products. Finally, the rather high contributions of PCNs to the total PCNs+PCDD/Fs+PCBs concentrations (0.9-50%, average of 9%) and the toxic equivalents (0.2-24%, average of 5%) show that these substances are not minor components of the PCNs+PCDD/Fs+PCBs cocktail.

HaloSeeker 1.0: A User-Friendly Software to Highlight Halogenated Chemicals in Nontargeted High-Resolution Mass Spectrometry Data Sets.

In the present work, we address the issue of nontargeted screening of organohalogenated chemicals in complex matrixes. A global strategy aiming to seek halogenated signatures in full-scan high-resolution mass spectrometry (HRMS) fingerprints was developed. The resulting all-in-one user-friendly application, HaloSeeker 1.0, was developed to promote the accessibility of associated in-house bioinformatics tools to a large audience. The ergonomic web user interface avoids any interactions with the coding component while allowing interactions with the data, including peak detection (features), deconvolution, and comprehensive accompanying manual review for chemical formula assignment. HaloSeeker 1.0 was successfully applied to a marine sediment HRMS data set acquired on a liquid chromatography-heated electrospray ionization [LC-HESI(-)] Orbitrap instrument ( R = 140 000 at m/z 200). Among the 4532 detected features, 827 were paired and filtered in 165 polyhalogenated clusters. HaloSeeker was also compared to three similar tools and showed the best performances. HaloSeeker's ability to filter and investigate halogenated signals was demonstrated and illustrated by a potential homologue series with C12H xBr yCl zO2 as a putative general formula.

Environmental Risks of Medium-Chain Chlorinated Paraffins (MCCPs): A Review.

Chlorinated paraffins are industrial chemicals that can be subdivided into short-chain (SCCP), medium-chain (MCCP), and long-chain (LCCP) chlorinated paraffins. The global production volumes of MCCPs are nowadays suspected to be much higher than those of S- and LCCPs, and the few available studies on the environmental occurrence of chlorinated paraffins report often higher MCCP concentrations than S- or LCCP concentrations in the environment. The present review focuses, therefore, on MCCPs specifically and provides a literature overview and a data analysis of the production volumes, PBT properties (persistence, bioaccumulation potential, and toxicity), and the worldwide measured concentrations of MCCP in environmental samples, biota, and humans. Furthermore, we include our own measurements of technical CP formulations from China, the major global producing country, to estimate the global production amounts of MCCPs. The key findings from this review are that (1) MCCPs are toxic to the aquatic environment, and the available data suggest that they are also persistent; (2) available time trends for MCCPs in soil, biota, and most of the sediment cores show increasing time trends over the last years to decades; and (3) MCCP concentrations in sediment close to local sources exceed toxicity thresholds (i.e., the PNEC). Our study shows that overall, MCCPs are of growing concern, and regulatory actions should be considered seriously.

Elucidation of non-intentionally added substances migrating from polyester-polyurethane lacquers using automated LC-HRMS data processing.

An untargeted strategy aiming at identifying non-intentionally added substances (NIAS) migrating from coatings was developed. This innovative approach was applied to two polyester-polyurethane lacquers, for which suppliers previously provided the identity of the monomers involved. Lacquers were extracted with acetonitrile and analyzed by liquid chromatography-high resolution mass spectrometry (LC-HRMS). Data, acquired in the full scan mode, were processed using an open-source R-environment (xcms and CAMERA packages) to list the detected features and deconvolute them in groups related to individual compounds. The most intense groups, accounting for more than 85% of cumulated feature intensities, were then investigated. A homemade database, populated with predicted polyester oligomer combinations from a relevant selection of diols and diacids, enabled highlighting the presence of 14 and 17 cyclic predicted polyester oligomers in the two lacquers, including three mutual combinations explained by common known monomers. Combination hypotheses were strengthened by chromatographic considerations and by the investigation of fragmentation patterns. Regarding unpredicted migrating substances, four monomers were hypothesised to explain several polyester or caprolactam oligomer series. Finally, considering both predicted and tentatively elucidated unpredicted oligomers, it was possible to assign hypotheses to features representing up to 82% and 90% of the cumulated intensities in the two lacquers, plus 9% and 3% (respectively) originating from the procedural blank. Graphical abstract Elucidation of non-intentionally added substances.

In ovo transformation of two emerging flame retardants in Japanese quail (Coturnix japonica).

Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and Dechlorane Plus (DP) are two chlorinated, alternative flame retardants that have been found in wild birds and bird eggs. Little is known about the fate and effect of these compounds in birds, especially during the vulnerable stages of embryonic development. To investigate the ability of birds to biotransform these compounds, an in ovo exposure experiment with Japanese quail eggs was performed. Quail eggs were injected in the yolk sac with 1000ng/g egg of TDCIPP (2.3 nmol/g ww), DP (1.5 nmol/g ww) or a mixture of both and were then incubated at 37.5°C for 17 days. To get a time-integrated understanding of the in ovo transformation of the compounds, one egg per treatment was removed from the incubator every day and analyzed for TDCIPP and its metabolite bis(1,3-dichloro-2-propyl) phosphate (BDCIPP) and/or for DP. By the end of the incubation period, TDCIPP was completely metabolized, while simultaneously BDCIPP was formed. The conversion of the parent compound into the metabolite did not occur proportionally and the concentration of BDCIPP showed a tendency to decrease when TDCIPP became depleted, both indicating that BDCIPP was further transformed into compounds not targeted for analysis. Further untargeted investigations did not show the presence of other metabolites, possibly due to the volatility of the metabolites. On the other hand, the DP concentration did not decrease during egg incubation. This study indicates that within the incubation period, avian embryos are able to biotransform TDCIPP, but not DP.

Synthesis and quantification of oligoesters migrating from starch-based food packaging materials.

The term oligomer refers to structurally diverse compounds coming from incomplete polymerisation or polymer degradation. Their ability to migrate into foodstuffs along with recent studies about their bioavailability and toxicity have risen concerns about the scarcity of standards needed to perform thorough analytical and toxicological studies. In this work, migration extracts of three starch-based biopolymers films for the packaging of fruits and vegetables were analysed according to European legislation 10/2011. Oligoesters analysed by UPLC-MS(QTOF) were the main non-intentionally added substances (NIAS) identified in the food simulants. A stepwise synthesis approach was used to synthesise and isolate eleven cyclic and linear oligoester standards ranging from 2 to 8 monomers based on adipic acid, 1,4-butanediol, isophtalic acid and propylene glycol monomers. These standards were characterised by 1H and 13C NMR as well as high resolution mass spectrometry. An overall high purity of > 98 % was achieved as detected by UPLC-MS(Orbitrap). The standards were then used to unequivocally identify the oligoesters in the migration assay samples by comparing their UPLC-MS/MS spectra, and to semi-quantify or fully quantify these migrant oligoesters. The oligoester quantification results deemed safe only one out of the three biopolymer films according to their threshold of toxicological concern concept. The work herein described aims to contribute towards the oligomers knowledge gaps, opening the door for comprehensive toxicological risk and absorption, distribution, metabolism, excretion and toxicity (ADMET) studies.

Non-targeted analysis of lipidic extracts by high-resolution mass spectrometry to characterise the chemical exposome: Comparison of four clean-up strategies applied to egg.

Biota samples are used to monitor chemical stressors and their impact on the ecosystem and to describe dietary chemical exposure. These complex matrices require an extraction step followed by clean-up to avoid damaging sensitive analytical instruments based on chromatography coupled to mass spectrometry. While interest for non-targeted analysis (NTA) is increasing, there is no versatile or generic sample preparation for a wide range of contaminants suitable for a diversity of biotic matrices. Among the contaminants' variety, persistent contaminants are mostly hydrophobic (mid- to non-polar) and bio-magnify through the lipidic fraction. During their extraction, lipids are generally co-extracted, which may cause matrix effect during the analysis such as hindering the acquired signal. The aim of this study was to evaluate the efficacy of four clean-up methods to selectively remove lipids from extracts prior to NTA. We evaluated (i) gel permeation chromatography (GPC), (ii) Captiva EMR-lipid cartridge (EMR), (iii) sulphuric acid degradation (H2SO4) and (iv) polydimethyl siloxane (PDMS) for their efficiency to remove lipids from hen egg extracts. Gas and liquid chromatography coupled with high-resolution mass spectrometry fitted with either electron ionisation or electrospray ionisation sources operating in positive and negative modes were used to determine the performances of the clean-up methods. A set of 102 chemicals with a wide range of physico-chemical properties that covers the chemical space of mid- to non-polar contaminants, was used to assess and compare recoveries and matrix effects. Matrix effects, that could hinder the mass spectrometer signal, were lower for extracts cleaned-up with H2SO4 than for the ones cleaned-up with PDMS, EMR and GPC. The recoveries were satisfactory for both GPC and EMR while those determined for PDMS and H2SO4 were low due to poor partitioning and degradation/dissociation of the compounds, respectively. The choice of the clean-up methods, among those assessed, should be a compromise that takes into account the matrix under consideration, the levels and the physico-chemical properties of the contaminants.

Quantification of chlorinated paraffins by chromatography coupled to high-resolution mass spectrometry - Part A: Influence of gas chromatography and ionisation source parameters.

The analysis of chlorinated paraffins (CPs) has become a major analytical challenge. GC-ECNI-HRMS coupling is often used to analyse and quantify them. However, the influence of certain GC and ECNI parameters on the responses of polychlorinated n-alkanes (PCAs), the dominant components of CPs, has hardly been studied. In this paper, we investigated not only the influence of GC column characteristics, but also oven, GC inlet and source temperatures for simultaneous analysis of PCAs with chain-length ranging from 10 up to 20 carbon atoms (PCAs-C10-20). Particular attention was paid to the absolute response and PCA homologue group pattern obtained for a CP technical mixture. The optimum conditions for a wide homologue group determination were GC inlet, final gradient and ion source temperatures set at 220-240 °C, 340 °C and 200 °C. At the same time, a higher response was obtained with the Optima 5HT column compared to Optima 1 column, and with a length and film thickness of 12.5 m and 0.25 µm, respectively. The homologue group pattern of the technical mixture studied was significantly modified as a function of the source and GC inlet temperatures, film thickness and composition of the stationary phase. Here we recommend conditions that will improve the overall PCA pattern, in order to better characterise their occurrence in future environmental monitoring and exposure assessment.

Quantification of chlorinated paraffins by chromatography coupled to high-resolution mass spectrometry - Part B: Influence of liquid chromatography separation.

The analysis of chlorinated paraffins (CPs) is today an analytical challenge. Indeed, it is still impractical to describe their real composition in terms of polychlorinated alkanes (PCAs) homologue groups, which dominate technical mixtures. The co-elution of PCA congeners generates interferences due to the competition phenomena which occur during the ionisation process as well as to the dependence of the ionisation sources on the PCA chemistry. Therefore, the aim of this study was to investigate the influence of chromatographic separation, by LC-ESI-HRMS coupling, on the PCA homologue group pattern and, eventually, on their determination in food samples from interlaboratory studies. For this, three different mobile phases and six LC chromatographic columns were studied in order to optimise the analysis of CP mixtures. The first results showed that the use of a MeOH/H2O mobile phase reveals more appropriately the higher chlorinated PCAs. However, using ACN/H2O led to less ion species, with almost exclusively [M + Cl]- adducts, formed using post-column dichloromethane addition. Regarding the choice of the stationary phases, Hypercarb column provided a completely different homologue group pattern from the other chromatographic columns, in relation with the stronger retention of PCAs. Among the other columns, the C30 column better highlighted the short-chain PCAs compared to the C18 column conventionally used. Because the regulations now concern short-chain CPs, the quantification of food samples was then carried out on the C30 column. The optimised LC-ESI-HRMS conditions using C30 column and MeOH/H2O solvent mixture led to a quantification of PCAs in samples from interlaboratory studies with satisfactory accuracy (|Z-score| ≤ 2) and precision (<15%).

Identification of non-volatile non-intentionally added substances from polyester food contact coatings and genotoxicity assessment of polyester coating's migrates.

Can's polyester coatings are intended to replace epoxy-phenolic ones due to rising safety concern regarding the potential release of bisphenol A under increased regulations and consumer pressure. In this study, hazard linked to the migration of non-intentionally added substances from a single polyester-coated tin plate (5 batches) to canned food has been studied. Migration tests were performed using acetonitrile (ACN) and ethanol (EtOH) 95 %. Non-targeted analyses by liquid chromatography-high-resolution mass spectrometry revealed the presence of four cyclic oligoesters classified as Cramer class III substances with an estimated exposure (calculated for French population only) below the threshold of toxicological concern value of 1.5 µg/kg b.w./day, suggesting a no safety concern. Moreover, migrates were tested using in vitro genotoxicity DNA damage response (DDR) test and mini mutagenicity test (MMT) with different strains of S. Typhimurium using direct incorporation (TA100, TA98, TA102, TA1537) and pre-incubation (TA100, TA98) methods. Samples were negative in both bioassays suggesting the absence of genotoxicity/mutagenicity of the mixtures. To verify any false negative response due to matrix effect, migrates were spiked with corresponding positive controls in parallel with the MMT and the DDR test. No matrix effect was observed in these experimental conditions.

Safety assessment of the substance amines, di-C14-C20-alkyl, oxidised, from hydrogenated vegetable oil, for use in food contact materials.

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) assessed the safety of amines, di-C14-C18-alkyl, oxidised, renamed by the Panel as amines, di-C14-C20-alkyl, oxidised, from hydrogenated vegetable oil. The substance amines, bis(hydrogenated tallow alkyl) oxidised, consisting of the same components, but originating from tallow, is currently authorised as FCM substance No 768. The vegetable-sourced substance is intended to be used at up to 0.1% w/w as antioxidant and/or stabiliser in the manufacture of polyolefin food contact materials (FCM) and articles intended for contact with dry, aqueous and acidic foods. The substance is a mixture consisting of linear N,N-dialkyl hydroxylamines and their corresponding amine, nitrone and oxime derivatives, as well as further components: tert-N-oxides, secondary amides and carboxylic acids. Specific migration was tested from polyethylene samples in 10% ethanol and 3% acetic acid for 2 h at 100°C followed by 10 days at 60°C. None of the non-authorised components were detected to migrate at detection limits (LoD) in the range 0.003-0.029 mg/kg. The LoD of authorised carboxylic acids was 0.35 mg/kg. The Panel reassessed the genotoxicity studies carried out on FCM No 768 and evaluated two new bacterial reverse mutation tests on the nitrone and oxime derivatives as well as new (qualitative/quantitative) structure-activity relationship (Q)SAR analyses on other components. The Panel concluded that the substance did not raise a concern for genotoxicity. The Panel concluded that the substance is not of safety concern for the consumers if it is used as an additive at 0.1% w/w in the manufacture of polyolefin FCM intended to be in contact with foods simulated by food simulants A, B, C and E, except for infant formula and human milk, for storage above 6 months at room temperature and below, including hot-fill conditions and heating up to 100°C for 2 h.

Safety assessment of mixtures of 1,9-nonanediamine (NMDA) and 2-methyl-1,8-octanediamine (MODA), for use in food contact materials.

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) assessed the safety of mixtures of 1,9-nonanediamine (NMDA) and 2-methyl-1,8-octanediamine (MODA) when used to produce polyamide food contact materials for contact with all food types for long-term storage at room temperature and below, including heating up to 121°C for up to 2 h. The polyamide material is also intended to be used for repeated use up to 121°C with short contact (up to 30 min). The polymer typically contains ■■■■■ of a low molecular weight fraction (LMWF, < 1000 Da). The specific migration was measured with polyamide samples in a set of migration tests with 3% acetic acid and 10% ethanol. NMDA and MODA were not detected at ■■■■■, respectively. The specific migration of the LMWF consisting of NMDA/MODA-related species was up to ■■■■■. The overall migration in olive oil was below the detection limit (3 mg/dm2). The most abundant migrating LMWF oligomers were identified. Toxicological studies were performed with NMDA, MODA and with polyamide formulations enriched in the LMWF. The results of genotoxicity assays did not raise a concern. From a repeated-dose oral 90-day toxicity study in rats, the Panel identified a no observed adverse effect level (NOAEL) of 1000 mg/kg body weight per day for the migrating LMWF. The CEP Panel concluded that NMDA/MODA mixtures do not raise a safety concern for the consumer when used as comonomer with terephthalic acid to manufacture polyamide articles intended for contact with all food types, except for infant formula and human milk, if the migration of NMDA and MODA does not exceed 0.05 mg/kg food (as a sum of the two substances) and if the migration of the LMWF consisting of NMDA/MODA-related species does not exceed 5 mg/kg food.

Safety assessment of the substance calcium tert-butylphosphonate for use in food contact materials.

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids assessed the safety of calcium tert-butylphosphonate, which is intended to be used as a nucleating agent up to 0.15% w/w for the manufacture of polyolefin food contact materials (FCM) and articles for single and repeated use, in contact with all types of food, including infant formula and human milk. Specific migration was tested using polyethylene samples in 10% ethanol, 3% acetic acid and 95% ethanol for 2 h at 100°C, followed by 238 h at 40°C. Results for all three simulants were near or below the limit of detection of 10 µg/kg. As the solubility of the substance is far above the reported migration and above 60 mg/kg food, no assessment of the particle fraction was needed, and the conventional risk assessment was followed. The substance did not induce gene mutations in bacterial cells and structural chromosomal aberrations in mammalian cells, thus, did not raise concern for genotoxicity. The Panel considered that the use of the substance did not give rise to safety concern related to neurotoxicity for the general population, but this conclusion could not be applied to infants below 16 weeks of age, due to their specific sensitivity and the absence of dedicated data. The Panel concluded that calcium tert-butylphosphonate does not raise a safety concern for the consumer if it is used as a nucleating agent up to 0.15% w/w in the manufacture of polyolefin FCM that are intended to be in contact with all types of food for storage above 6 months at room temperature and below, including temperatures up to 100°C for maximum 2 h and up to 130°C for short durations. The Panel could not evaluate the safety of use to manufacture FCM for contact with infant formula and human milk.

An international investigation of chlorinated paraffin concentrations and homologue distributions in indoor dust.

In this study, very short-, short-, medium-, and long-chain chlorinated paraffins (vSCCPs, SCCPs, MCCPs and LCCPs, respectively) were measured in 40 indoor dust samples from four countries including Japan (n = 10), Australia (n = 10), Colombia (n = 10) and Thailand (n = 10). Homologues of the chemical formula CxH(2x+2-y)Cly ranging C6-36 and Cl3-30 were analysed using liquid chromatography coupled to Orbitrap high resolution mass spectrometry (LC-Orbitrap-HRMS) and integrated using novel custom-built CP-Seeker software. CPs were detected in all dust samples with MCCPs the dominant homologue group in all countries. Overall median ∑SCCP, ∑MCCP and ∑LCCP (C18-20) concentrations determined in dust samples were 30 µg/g (range; 4.0-290 µg/g), 65 µg/g (range; 6.9-540 µg/g) and 8.6 µg/g (range; <1.0-230 µg/g), respectively. Of the quantified CP classes, overall concentrations were generally highest in the samples from Thailand and Colombia, followed by Australia and Japan. vSCCPs with C≤9 were detected in dust from each country with an overall frequency of 48%, while LCCPs (C21-36) were present in 100% of samples. Estimated daily intakes (EDIs) calculated for SCCPs and MCCPs relating to ingestion of contaminated indoor dust were considered not to represent health risks based on currently available toxicological data using the margin of exposure (MOE) approach. To the authors' knowledge, this study provides the first data on CPs in indoor dust from Japan, Colombia and Thailand, and is among the first reports of vSCCPs in indoor dust, globally. These findings indicate that further toxicological data and the availability of appropriate analytical standards are needed to evaluate the potential for negative health outcomes deriving from exposure to vSCCPs and LCCPs.

The epigenetic hallmark of early-life α-hexabromocyclododecane exposure: From cerebellar 6-mA levels to locomotor performance in adulthood.

There is a growing evidence that methylation at the N6 position of adenine (6-mA), whose modulation occurs primarily during development, would be a reliable epigenetic marker in eukaryotic organisms. The present study raises the question as to whether early-life exposure to α-hexabromocyclododecane (α-HBCDD), a brominated flame retardant, may trigger modifications in 6-mA epigenetic hallmarks in the brain during the development which, in turn could affect the offspring behaviour in adulthood. Pregnant Wistar rats were split into two groups: control and α-HBCDD (66 ng/kg/per os, G0-PND14). At PND1, α-HBCDD levels were assessed in brain and liver by LC-MS/MS. At PND14, DNA was isolated from the offspring's cerebellum. DNA methylation was measured by 6-mA-specific immunoprecipitation and Illumina® sequencing (MEDIP-Seq). Locomotor activity was finally evaluated at PND120. In our early-life exposure model, we confirmed that α-HBCDD can cross the placental barrier and be detected in pups at birth. An obvious post-exposure phenotype with locomotor deficits was observed when the rats reached adulthood. This was accompanied by sex-specific over-methylation of genes involved in the insulin signaling pathway, MAPK signaling pathway as well as serotonergic and GABAergic synapses, potentially altering the normal process of neurodevelopment with consequent motor impairments crystalized at adulthood.

Thorough investigation of non-volatile substances extractible from inner coatings of metallic cans and their occurrence in the canned vegetables.

Since the decline of the use of bisphenol A, the chemistry of the varnishes and coatings which are applied to the inner surfaces of metallic food contact materials is poorly documented. We hypothesised that can coatings are now diverse and bring forth various non-intentionally added substances (NIAS) to be described. Investigating complex components such as NIAS requires demanding non-targeted approaches. We investigated the coatings of 12 vegetable cans from the French market. More than 125 substances were pinpointed, among them 84 oligoester combinations from 8 diols and 4 diacids. Thus, oligoesters were the dominant family. Additives such as epoxidised soybean oil, bisphenol A diglycidyl ether and benzoguanamine derivatives and phenol-formaldehyde oligomers were also identified. A software for exploring databases of theoretical combinations of polyester and phenol-formaldehyde resin components (NIAS-db 1.0) was made available. The stepwise organic synthesis of native and deuterated combinations of neopentyl glycol and isophthalic acid (4 and 8 units, linear and cyclic) enabled a higher confidence level and monitoring in vegetable extracts. Migration of oligoesters averaged 330 µg/kg in the drained vegetables (43-1600 µg/kg). This study sheds light on the need to fulfil a proper risk assessment on this NIAS family (exposure and hazard characterisation).

Determination of chlorinated paraffins (CPs): Analytical conundrums and the pressing need for reliable and relevant standards.

The determination of chlorinated paraffins (CPs) has posed an intractable challenge in analytical chemistry for over three decades. The combination of an as yet unspecifiable number (tens - hundreds of thousands) of individual congeners in mass produced commercial CP mixtures and the steric interactions between them, contrive to defy efforts to characterise their residual occurrences in environmental compartments, food and human tissues. However, recent advances in instrumentation (mass spectrometric detectors and nuclear magnetic resonance), combined with interlaboratory studies, have allowed a better insight into the nature of the conundrums. These include the variability of results, even between experienced laboratories when there is insufficient matching between analytical standards and occurrence profiles, the poor (or no) response of some instrumentation to some CP congener configurations (multiple terminal chlorines or < four chlorines) and the occurrence of chlorinated olefins in commercial mixtures. The findings illustrate some limitations in the existing set of commercially available standards. These include cross-contamination of some standards (complex CP mixtures), an insufficient number of single chain standards (existing ones do not fully reflect food/biota occurrences), lack of homologue group standards and unsuitability of some configurationally defined CP congeners/labelled standards (poor instrument response and a smaller likelihood of occurrence in commercial mixtures). They also indicate an underestimation in reported occurrences arising from those CPs that are unresponsive during measurement. A more extensive set of standards is suggested and while this might not be a panacea for accurate CP determination, it would reduce the layers of complexity inherent in the analysis.

Identification by volatolomics of hydrocarbon, oxygenated, sulfur and aromatic markers of livestock exposure to α-hexabromocyclododecane.

Volatile organic compounds (VOC)-based metabolomics, or volatolomics, was investigated for revealing livestock exposure to chemical contamination. Three farm animals, namely laying hens, broilers, and pigs, were experimentally exposed to 5 or 50 ng α-HBCDD g-1 feed. Liver and egg yolk for hens were analysed by headspace-SPME-GC-MS to reveal candidate markers of the livestock exposure to α-HBCDD. For hens, 2-butanol was found as marker in egg. In liver, twelve VOCs were highlighted as markers, with three aromatic VOCs - styrene, o-xylene, α-methylstyrene - highlighted for the two α-HBCDD doses. For broilers, six markers were revealed, with interestingly, styrene and phenol which were also found as markers in hen liver. For pigs, ten markers were revealed and the seven tentatively identified markers were oxygenated and sulfur VOCs. The candidate markers tentatively identified were discussed in light of previous volatolomics data, in particular from a γ-HBCDD exposure of laying hens.

Mixture Risk Assessment of Complex Real-Life Mixtures-The PANORAMIX Project.

Humans are involuntarily exposed to hundreds of chemicals that either contaminate our environment and food or are added intentionally to our daily products. These complex mixtures of chemicals may pose a risk to human health. One of the goals of the European Union's Green Deal and zero-pollution ambition for a toxic-free environment is to tackle the existent gaps in chemical mixture risk assessment by providing scientific grounds that support the implementation of adequate regulatory measures within the EU. We suggest dealing with this challenge by: (1) characterising 'real-life' chemical mixtures and determining to what extent they are transferred from the environment to humans via food and water, and from the mother to the foetus; (2) establishing a high-throughput whole-mixture-based in vitro strategy for screening of real-life complex mixtures of organic chemicals extracted from humans using integrated chemical profiling (suspect screening) together with effect-directed analysis; (3) evaluating which human blood levels of chemical mixtures might be of concern for children's development; and (4) developing a web-based, ready-to-use interface that integrates hazard and exposure data to enable component-based mixture risk estimation. These concepts form the basis of the Green Deal project PANORAMIX, whose ultimate goal is to progress mixture risk assessment of chemicals.