Christine Baduel

Towards development of a rapid and effective non-destructive testing strategy to identify brominated flame retardants in the plastics of consumer products.

Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants (BFRs) once extensively used in the plastics of a wide range of consumer products. The listing of certain congeners that are constituents of commercial PBDE mixtures (including c-octaBDE) in the Stockholm Convention and tightening regulation of many other BFRs in recent years have created the need for a rapid and effective method of identifying BFR-containing plastics. A three-tiered testing strategy comparing results from non-destructive testing (X-ray fluorescence (XRF)) (n=1714), a surface wipe test (n=137) and destructive chemical analysis (n=48) was undertaken to systematically identify BFRs in a wide range of consumer products. XRF rapidly identified bromine in 92% of products later confirmed to contain BFRs. Surface wipes of products identified tetrabromobisphenol A (TBBPA), c-octaBDE congeners and BDE-209 with relatively high accuracy (>75%) when confirmed by destructive chemical analysis. A relationship between the amounts of BFRs detected in surface wipes and subsequent destructive testing shows promise in predicting not only the types of BFRs present but also estimating the concentrations present. Information about the types of products that may contain persistent BFRs will assist regulators in implementing policies to further reduce the occurrence of these chemicals in consumer products.

Development of sample extraction and clean-up strategies for target and non-target analysis of environmental contaminants in biological matrices

Recently, there has been an increasing trend towards multi-targeted analysis and non-target screening methods as a means to increase the number of monitored analytes. Previous studies have developed biomonitoring methods which specifically focus on only a small number of analytes with similar physico-chemical properties. In this paper, we present a simple and rapid multi-residue method for simultaneous extraction of polar and non-polar organic chemicals from biological matrices, containing up to 5% lipid content. Our method combines targeted multi-residue analysis using gas chromatography triple quadrupole mass spectrometry (GC-QqQ-MS/MS) and a multi-targeted analysis complemented with non-target screening using liquid chromatography coupled to a quadrupole time of flight mass spectrometry (LC-QTOF-MS/MS). The optimization of the chemical extraction procedure and the effectiveness of different clean-up methods were evaluated for two biological matrices: fish muscle (lipid content ∼2%) and breast milk (∼4%). To extract a wide range of chemicals, the partition/extraction procedure used for the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) approach was tested as the initial step for the extraction of 77 target compounds covering a broad compound domain. All the target analytes have different physico-chemical properties (log Kow ranges from -0.3 to 10) and cover a broad activity spectrum; from polar pesticides, pharmaceuticals, personal care products (PPCPs) to highly lipophilic chemicals such as polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and organochloride pesticides (OCPs). A number of options were explored for the clean-up of lipids, proteins and other impurities present in the matrix. Zirconium dioxide-based sorbents as dispersive solid-phase extraction (d-SPE) and protein-lipid removal filter cartridges (Captiva ND Lipids) provided the best results for GC-MS and LC-MS analysis respectively. The method was fully validated for samples of fish muscle and breast milk through the evaluation of recoveries, matrix effects, limit of quantification, linearity and precision (inter-day and intra-day). Mean recoveries (n=5) were between 70 and 120% with relative standard deviations (RSD) less than 20% in most of the cases. GC-MS/MS LOQs ranged from 0.08 to 3μg/kg and LC-QTOF-MS/MS LOQs ranged from 0.2 to 9μg/kg. The developed strategy was successfully applied for analysis of real samples; 22 target analytes were found in the breast milk samples and 10 in the fish samples. Non-target analysis allowed the detection and identification of an additional 14 contaminants and metabolites in the samples.

Perfluoroalkyl substances in a firefighting training ground (FTG), distribution and potential future release

The present study investigates the occurrence and fate of 15 perfluoroalkyl substances (PFASs) and one fluorotelomer sulfonate from a firefighting training ground (FTG) that was contaminated by intensive use of aqueous film forming foams (AFFF). The contamination levels and their spatial and vertical distribution are assessed in the structure. At the surface of the pad, perfluorooctane sulphonate (PFOS) is the dominant PFASs measured, with concentration varying from 10 to 200 μg g(-1). PFASs were also detected in a concrete core at up to 12 cm depth, suggesting the vertical movement and higher transport potential of shorter chain compounds. The estimated mass load of linear PFOS in this specific pad was >300 g with a total of 1.7 kg for the sum of all PFASs analyzed. The kinetics of desorption of PFOS, PFOA and 6:2FTS from the concrete into an overlaying static water volume has been measured under field conditions at two constant temperatures. Fitting the desorption data and estimated rainfall/runoff to a kinetic model suggests that this and similar firefighting training pads will likely remain a source of PFASs for many decades (t0.5=25 years for PFOS).

Use of pooled samples to assess human exposure to parabens, benzophenone-3 and triclosan in Queensland, Australia

Parabens, benzophenone-3 and triclosan are common ingredients used as preservatives, ultraviolet radiation filters and antimicrobial agents, respectively. Human exposure occurs through consumption of processed food and use of cosmetics and consumer products. The aim of this study was to provide a preliminary characterisation of exposure to selected personal care product chemicals in the general Australian population. De-identified urine specimens stratified by age and sex were obtained from a community-based pathology laboratory and pooled (n=24 pools of 100). Concentrations of free and total (sum of free plus conjugated) species of methyl, ethyl, propyl and butyl paraben, benzophenone-3 and triclosan were quantified using isotope dilution tandem mass spectrometry; with geometric means 232, 33.5, 60.6, 4.32, 61.5 and 87.7ng/mL, respectively. Age was inversely associated with paraben concentration, and females had concentrations approximately two times higher than males. Total paraben and benzophenone-3 concentrations are significantly higher than reported worldwide, and the average triclosan concentration was more than one order of magnitude higher than in many other populations. This study provides the first data on exposure of the general Australian population to a range of common personal care product chemical ingredients, which appears to be prevalent and warrants further investigation.

Occurrence and distribution of brominated flame retardants and perfluoroalkyl substances in Australian landfill leachate and biosolids

The levels of perfluroalkyl substances (PFASs), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDDs) were studied in Australian landfill leachate and biosolids. Leachate was collected from 13 landfill sites and biosolids were collected from 16 wastewater treatment plants (WWTPs), across Australia. Perfluorohexanoate (PFHxA) (12-5700ng/L) was the most abundant investigated persistent, bioaccumulative and toxic (PBT) chemical in leachate. With one exception, mean concentrations of PFASs were higher in leachate of operating landfills compared to closed landfills. Polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane isomers (HBCDDs) were detected typically at operating landfills in comparatively lower concentrations than the PFASs. Decabromodiphenyl ether (BDE-209) (<0.4-2300ng/g) and perfluoroctanesulfonate (PFOS) (<LOD-380ng/g) were the predominant PBTs detected in biosolids. Using data provided by sites, the volume of leachate discharged to WWTPs for treatment was small (<1% total inflow), and masses of PBTs transferred reached a maximum of 16g/yr (PFHxA). A national estimate of masses of PBTs accumulated in Australian biosolids reached 167kg/yr (BDE-209), a per capita contribution of 7.2±7.2mg/yr. Nationally, approximately 59% of biosolids are repurposed and applied to agricultural land. To our knowledge this study presents the first published data of PFASs and HBCDDs in Australian leachate and biosolids.

Anionic, Cationic, and Nonionic Surfactants in Atmospheric Aerosols from the Baltic Coast at Askö, Sweden: Implications for Cloud Droplet Activation

Recent analyses of atmospheric aerosols from different regions have demonstrated the ubiquitous presence of strong surfactants and evidenced surface tension values, σ, below 40 mN m(-1), suspected to enhance the cloud-forming potential of these aerosols. In this work, this approach was further improved and combined with absolute concentration measurements of aerosol surfactants by colorimetric titration. This analysis was applied to PM2.5 aerosols collected at the Baltic station of Askö, Sweden, from July to October 2010. Strong surfactants were found in all the sampled aerosols, with σ = (32-40) ± 1 mN m(-1) and concentrations of at least 27 ± 6 mM or 104 ± 21 pmol m(-3). The absolute surface tension curves and critical micelle concentrations (CMC) determined for these aerosol surfactants show that (1) surfactants are concentrated enough in atmospheric particles to strongly depress the surface tension until activation, and (2) the surface tension does not follow the Szyszkowski equation during activation but is nearly constant and minimal, which provides new insights on cloud droplet activation. In addition, both the CMCs determined and the correlation (R(2) ∼ 0.7) between aerosol surfactant concentrations and chlorophyll-a seawater concentrations suggest a marine and biological origin for these compounds.

Spatio-temporal assessment of perfluorinated compounds in the Brisbane River system, Australia: impact of a major flood event.

Perfluorinated chemicals including PFOA and PFOS have been widely used in consumer products and have become ubiquitous pollutants widely distributed in the aqueous environment. Following a major flood event in 2011, water samples were collected along a spatial gradient of the Brisbane River system to provide an initial estimate of the release of PFASs from flooded urban areas. PFOA (mean concentrations 0.13-6.1 ng L(-1)) and PFOS (mean concentrations 0.18-15 ng L(-1)) were the most frequently detected and abundant PFASs. Mean total PFASs concentrations increased from 0.83 ng L(-1) at the upstream Wivenhoe Dam to 40 ng L(-1) at Oxley Creek, representing an urban catchment. Total masses of PFOA and PFOS delivered into Moreton Bay from January to March were estimated to be 5.6 kg and 12 kg respectively. From this study, urban floodwaters appear to be a previously overlooked source of PFASs into the surrounding environment.

Fate and redistribution of perfluoroalkyl acids through AFFF-impacted groundwater

Leaching of perfluoroalkyl acids (PFAAs) from a local point source, a fire-fighting training area, has led to extensive contamination of a groundwater aquifer which has spread underneath part of a nearby town, Oakey, situated in the State of Queensland, Australia. Groundwater is extracted by residents from privately owned wells for daily activities such as watering livestock and garden beds. The concentration of 10 PFAAs in environmental and biological samples (water, soil, grass, chicken egg yolk, serum of horses, cattle and sheep), as well as human serum was investigated to determine the extent of contamination in the town and discuss fate and redistribution of PFAAs. Perfluorooctane sulfonate (PFOS) was the dominant PFAA in all matrices investigated, followed by perfluorohexane sulfonate (PFHxS). PFOS concentrations measured in water ranged between <0.17-14μg/L, concentrations of PFHxS measured between <0.07-6μg/L. PFAAs were detected in backyards (soil, grass), livestock and chicken egg yolk. Significant differences (p<0.01) in PFOS and PFHxS concentrations in two groups of cattle were found, one held within the contamination plume, the other in the vicinity but outside of the contamination plume. In human serum PFOS concentrations ranged from 38 to 381μg/L, while PFHxS ranged from 39 to 214μg/L. Highest PFOS concentrations measured in human serum were >30-fold higher compared to the general Australian population. Through use of contaminated groundwater secondary sources of PFAA contamination are created on private property, leading to further redistribution of contamination and creation of additional human exposure pathways.

Organophosphate and brominated flame retardants in Australian indoor environments: Levels, sources, and preliminary assessment of human exposure

Concentrations of nine organophosphate flame retardants (OPFRs) and eight polybrominated diphenyl ethers (PBDEs) were measured in samples of indoor dust (n = 85) and air (n = 45) from Australian houses, offices, hotels, and transportation (buses, trains, and aircraft). All target compounds were detected in indoor dust and air samples. Median ∑9OPFRs concentrations were 40 μg/g in dust and 44 ng/m3 in indoor air, while median ∑8PBDEs concentrations were 2.1 μg/g and 0.049 ng/m3. Concentrations of FRs were higher in rooms that contained carpet, air conditioners, and various electronic items. Estimated daily intakes in adults are 14000 pg/kg body weight/day and 330 pg/kg body weight/day for ∑9OPFRs and ∑8PBDEs, respectively. Our results suggest that for the volatile FRs such as tris(2-chloroethyl) phosphate (TCEP) and TCIPP, inhalation is expected to be the more important intake pathway compared to dust ingestion and dermal contact.

Development and validation of a multi-residue method for the analysis of brominated and organophosphate flame retardants in indoor dust

Flame retardants are associated to numerous adverse health effects, can accumulate in humans and have been used intensively worldwide. Recently, dust has been identified as a major human exposure route for flame retardants. The aim of this study was to develop a multi-residue method using a two-step SPE purification. It enabled us to effectively limit co-extracted matrix/interferets and therefore a simultaneous analysis of brominated and organophosphate flame retardants for indoor dust was achieved. The optimized method was validated according to standard protocol and achieved good accuracy and reproducibility (percent error ranged from -29% to 28%). Standard Reference Material (SRM) for dust was also analysed, and good agreement was found with reported brominated and organophosphate flame retardants (OPFRs) concentrations. The applicability of the validated method was demonstrated by the analysis of ten indoor dust samples from ten Australian homes. Overall 89% of the analytes were detected in these samples. The average concentrations of ∑OPFRs and ∑PBDEs in those samples were 41 and 3.6μg/g, respectively. Tris(2-butoxyethyl) phosphate and tris(2-chloroisopropyl) phosphate were the most abundant OPFRs, accounting for 57-92% ∑OPFRs, while decabromodiphenyl ether dominated the Polybrominated diphenyl ethers (PBDE) congeners contributing between 71-94% to the ∑PBDEs.