Abstract :
[en] Aims
Brominated flame retardants (BFRs) were widely used these past decades in textiles, plastics, electric or electronic equipments, etc, to prevent or reduce the ignition and rate of combustion. Due to their persistence and health concerns, the production and uses of several BFRs were banned in many countries. Recently, emerging BFRs have been developed as alternatives to the banned or restricted chemicals, but data on their human exposure are still scarce. The aims of this study were firstly to develop and validate a fast and simple analytical procedure to measure 15 historical and novel BFRs in human serum, allowing high throughput analyses for large scale epidemiological studies. Secondly, this new method was used to assess the environmental exposure of a general population living in the Province of Liege (Belgium).
Materials and Methods
1 ml of serum previously equilibrated for 1 hour with internal standard and acetic acid glacial was extracted twice using a hexane/acetone mixture (95/5). After evaporation till 0.5ml, the extract was loaded on 1ml PHREE cartridge (Phenomenex) to remove lipid traces, and transferred to GC vial with nonane as keeper. The final determination was performed on a gas chromatograph (GC) coupled to a mass spectrometer (7890A GC/7000A Triple Quad MS, Agilent Technologies), and equipped with a 15 meters RTX-1614 (Restek). The MS operated in Negative Chemical ionization mode using methane as reagent gas. 252 volunteers living in the Province of Liege (Belgium) were recruited between February and May 2015 from the High Schools and Provincial Offices, and provided urine and blood samples. From this enrollment, the serum of 43 participants aged from 18 to 29 years old, and 50 aged from 40 to 49 years were analyzed for BFRs.
Results and Conclusions
The fast extraction procedure provided clean extracts and good recovery rates from small serum volume and did not need further labor and time consuming purification steps. The 15m length RTX-1614 allowed the simultaneous measurement of the 15 BFRs including PBDE-209 in a single injection. From the 15 initial targeted BFRs, 8 PBDEs including PBDE-209, 1 hexabromobiphenyl (PBB-153), pentabromotoluene (PBT), hexabromobenzene (HxBBz), and pentabromoethylbenzene (PBEB) were successfully validated according the total error approach. This user-friendly method was demonstrated to be accurate, exact, and could be easily implemented in routine laboratories. The limit of quantification was defined at 47.2 pg/ml for PBDE-209, the others ranging from 1 to 9.2 pg/ml.
Within the population studied, all targeted BFRs were measured with detection frequencies (DF) ranging from 2.2 to 39.8%, except for PBDE-183 and PBEB which were never detected. The most often found BFRs were successively PBDE-153, -154, -47, -100 and -99. The geometric means ranged between 0.11 and 3.81 ng/g lipid depending on the compound, which were far lower than levels usually reported in North America or in China (1). Women showed significantly higher DF than men for PBDE-47, -99, -100 but lower for PBDE-153, suggesting different metabolism efficiency or different pollutant storage according to gender. On the other hand, the older age class (40-49 yr) showed higher DF only for PBB-153 and PBDE-154.
References :
(1) Zhu et al., Brominated Flame Retardants in serum from the general population in Nothern China. Environ. Sci. Technol. 2009, 43 (18): 6963-6968
