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Background As one of the speculated bisphenols to replace bisphenol A (BPA), bisphenol F (BPF), naturally present in mustard, is structurally similar to BPA and may have similar estrogenic activity, but information on its toxicity is very limited compared to BPA. Objective In order to support the toxicology study of BPF at Heath Canada, a GC–MS method based on solid-phase extraction (SPE) and derivatization was developed for analysis of BPF in liver samples. Methods Samples were treated with β-glucuronidase to convert BPF glucuronide to free BPF for analysis of total BPF. Results The method was validated for free BPF at different spiking levels, and recoveries ranged from 90–97.5% with RSDs from 0.11–5.54%. The method was also validated for glucuronide-conjugated BPF at different spiking levels of BPF mono-β-D-glucuronide: recoveries ranged from 72.3–93.3% with RSDs from 1.7–8.94%. The method was used to analyze 60 liver tissue samples from rats dosed with BPF at different levels in a toxicology study. Free and glucuronide-conjugated BPF were not detected in any of the control samples, which were not dosed with BPF (average method detection limit: 0.31 ng/g) but detected in all the other liver tissue samples with levels increasing at higher doses. The percentage of glucuronide-conjugated BPF in total BPF varied among the liver samples, from as low as 9.8% to as high as 77.9%, indicating the importance of analyzing biological samples for BPF in both free and conjugated forms for total exposure. Conclusion A GC–MS method based on solid-phase extraction (SPE) and derivatization was developed for analysis of both free and glucuronide-conjugated BPF in liver samples. This method was validated not only for free BPF, but also for mono-β-D-glucuronide-conjugated BPF for the first time to confirm the efficiency of the deconjugation procedure with enzyme. Highlights This method can be adapted and applied for analysis of free and glucuronide-conjugated BPF in other biological samples with appropriate validation in target sample matrixes. [ABSTRACT FROM AUTHOR]

AbstractAs an alternative to bisphenol A (BPA), bisphenol S (BPS) has been used as an ink developer in thermal paper products including price labels on food packaging which have been suggested as the sources of BPS found at high levels in packaged fish samples. BPS in the printed price labels glued onto the outside of plastic film could migrate indirectly from the printed surface through the paper, adhesive and film into the food. In order to investigate if price labels could also be the sources of BPS detected in the meat samples in our previous studies, meat and other food samples packaged under different conditions were collected, and BPS in these samples together with the price labels on the corresponding packaging were extracted with solvent followed by solid phase extraction and stable isotope dilution LC-MS/MS analysis. BPS was detected at very high levels (161.7–222.4 µg/cm2) in all the five sticker type of price labels, indicating BPS being the dominant if not the sole ink developer. BPS was also detected in all the 26 continuous roll type of price labels but at very low levels (0.017–18 ng/cm2), indicating that the dominant ink developer is likely one of the other alternatives, rather than BPS. Despite BPS being detected in all price labels on packaging of fish, meat, and cheese samples, BPS was not detected or detected in only a few fish, meat, and cheese samples at levels considerably lower than the current EU specific migration limit (SML) of 50 ng/g food for BPS authorised under Regulation (EU) 10/2011. [ABSTRACT FROM AUTHOR]

ABSTRACT Three diesel fuels, one oil sand-derived (OSD) diesel serving as base fuel, one cetane-enhanced base fuel, and one oxygenate [diethylene glycol dimethyl ether (DEDM)]-blended base fuel, were tested for [...]

Tenax-TA, Carbotrap, Tenax-GR and Chromosorb were exposed to ozone at 180 ppb for one week to test the effect of ozone on adsorbents during passive sampling of air. Passive sampling followed by thermal desorption into a gas chromatograph is used in sampling and analysis of volatile organic compounds (VOCs) in rural air. However, it is limited by the significant increase in the blank levels of adsorbents during storage. The formation of artifact compounds on adsorbents and the effects of ozone on adsorbed VOCs are presented.

The article presents the discussion on Journal of AOAC INTERNATIONAL (the Journal) were released in 1915 under the name Journal of the Association of Official Agricultural Chemists including analytical sciences in both chemistry and microbiology.

Levels of most VOCs in foods are usually low because of their volatility, and human exposure to VOCs is expected to be mainly via inhalation of ambient and indoor air. However, dietary exposures to VOCs can be significant to overall exposures if elevated concentrations of VOCs are present in foods consumed in high amounts and/or on a regular basis, and this was demonstrated in this study with the occurrence data of toluene from the recent 2014 Canadian Total Diet Study (TDS). Concentrations of toluene in the composite samples of most food types from the 2014 TDS are low and similar to the results from the previous 2007 TDS with some exceptions, such as beef steak (670 ng/g (2014 TDS) vs. 14 ng/g (2007 TDS)), poultry, chicken and turkey (307 ng/g (2014 TDS) vs. 8.8 ng/g (2007 TDS)). Toluene concentrations in most of the grain-based and fast food composite samples from the 2014 TDS are considerably higher than those from the 2007 TDS, with the highest level of 4655 ng/g found in the composite sample of crackers from the 2014 TDS (compared to 18 ng/g from 2007 TDS). Dietary exposure estimates for toluene based on the occurrence results from the 2014 TDS show that for most of the age groups, grain-based foods are the primary source, accounting for an average of 77.5% of the overall toluene intake from the diet. The highest dietary exposures to toluene were observed for the adult age groups, with estimated average exposures ranging from 177.4 to 184.5 µg/d. Dietary exposure estimates to toluene are well below oral doses associated with toxicological effects and also below the maximum estimated intake (819 µg/d) from air inhalation for adult group (20 - 70 years) based on the results from CEPA (Canadian Environmental Protection Act) assessment in 1992. [ABSTRACT FROM AUTHOR]

Solid phase extraction (SPE) of large volumes of water and beverage products was investigated for the GC-MS analysis of bisphenol A (BPA), bisphenol AF (BPAF), bisphenol F (BPF), bisphenol E (BPE), and bisphenol B (BPB). While absolute recoveries of the method were improved for water and some beverage products (e.g. diet cola, iced tea), breakthrough may also have occurred during SPE of 200 mL of other beverages (e.g. BPF in cola). Improvements in method detection limits were observed with the analysis of large sample volumes for all bisphenols at ppt (pg/g) to sub-ppt levels. This improvement was found to be proportional to sample volumes for water and beverage products with less interferences and noise levels around the analytes. Matrix effects and interferences were observed during SPE of larger volumes (100 and 200 mL) of the beverage products, and affected the accurate analysis of BPF. This improved method was used to analyse bisphenols in various beverage samples, and only BPA was detected, with levels ranging from 0.022 to 0.030 ng/g for products in PET bottles, and 0.085 to 0.32 ng/g for products in cans. [ABSTRACT FROM AUTHOR]