Christie Gallen

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.

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.

Spatial and temporal variability in pesticide exposure downstream of a heavily irrigated cropping area: application of different monitoring techniques

Pesticide exposure threatens many freshwater and estuarine ecosystems around the world. This study examined the temporal and spatial trends of pesticide concentrations in a waterway within an agriculturally developed dry-tropics catchment using a combination of grab and passive sampling methods over a continuous two-year monitoring program. A total of 43 pesticide residues were detected with 7 pesticides exceeding ecologically relevant water quality guidelines/trigger values during the study period and 4 (ametryn, atrazine, diuron, and metolachlor) of these exceeding guidelines for several months. The presence and concentration of the pesticides in the stream coincided with seasonal variability in rainfall, harvest timing/cropping cycle, and management changes. The sampling approach used demonstrates that the application of these complementary sampling techniques (both grab and passive sampling methods) was effective in establishing pesticide usage patterns in upstream locations where application data are unavailable.

Environmental monitoring of selected pesticides and organic chemicals in urban stormwater recycling systems using passive sampling techniques.

Water recycling via aquifers has become a valuable tool to augment urban water supplies in many countries. This study reports the first use of passive samplers for monitoring of organic micropollutants in Managed Aquifer Recharge (MAR). Five different configurations of passive samplers were deployed in a stormwater treatment wetland, groundwater monitoring wells and a recovery tank to capture a range of polar and non-polar micropollutants present in the system. The passive samplers were analysed for a suite of pesticides, polycyclic aromatic hydrocarbons (PAHs) and other chemicals. As a result, 17 pesticides and pesticide degradation products, 5 PAHs and 8 other organic chemicals including flame retardants and fragrances were detected in urban stormwater recharging Aquifer Storage and Recovery (ASR) and an Aquifer Storage Transfer and Recovery (ASTR) system. Of the pesticides detected, diuron, metolachlor and chlorpyrifos were generally detected at the highest concentrations in one or more passive samplers, whereas chlorpyrifos, diuron, metolachlor, simazine, galaxolide and triallate were detected in multiple samplers. Fluorene was the PAH detected at the highest concentration and the flame retardant Tris(1-chloro-2-propyl)phosphate was the chemical detected in the greatest abundance at all sites. The passive samplers showed different efficiencies for capture of micropollutants with the Empore disc samplers giving the most reliable results. The results indicate generally low levels of organic micropollutants in the stormwater, as the contaminants detected were present at very low ng/L levels, generally two to four orders of magnitude below the drinking water guidelines (NHMRC, 2011). The efficiency of attenuation of these organic micropollutants during MAR was difficult to determine due to variations in the source water concentrations. Comparisons were made between different samplers, to give a field-based calibration where existing lab-based calibrations were unavailable.

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.

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.

Australia-wide assessment of perfluoroalkyl substances (PFASs) in landfill leachates

Leachate from 27 landfills was analysed for nine perfluoroalkyl substances (PFASs). Five PFASs were detected ubiquitously, with perfluorohexanoate (PFHxA) the predominant PFAS (mean 1700ng/L; range 73-25,000ng/L). Despite the complexity of landfill-specific factors, some general trends in PFAS concentrations were observed. Mean concentrations of eight PFASs were higher in operating landfills (or landfill cells) accepting primarily municipal waste, compared to closed municipal landfills. Landfills accepting primarily construction and demolition wastes produced leachate that had higher mean PFAS concentrations than municipal landfills. Younger landfills appeared to have a higher burden of waste containing PFASs (or their precursors), as significant relationships (p<0.05) were observed between selected PFAS concentrations and landfill age. Increasing pH and total organic carbon (TOC) in leachate were associated with increased concentrations of several PFASs. Eight landfills discharged leachate to wastewater treatment plants (WWTPs). Estimated masses of PFASs discharged reached a maximum of 62g annually (PFHxA), with a national estimate reaching 31kg (PFHxA) annually. The practise of treating leachate at WWTPs allows redistribution of PFASs between the solid and liquid waste streams, although the contribution of leachate to the total load of PFASs entering WWTPs is minor compared to domestic waste water sources.

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.

BDE-209 in the Australian Environment: Desktop review

The commercial polybrominated diphenyl ether (PBDE) flame retardant mixture c-decaBDE is now being considered for listing on the Stockholm Convention on Persistent Organic Pollutants. The aim of our study was to review the literature regarding the use and detection of BDE-209, a major component of c-decaBDE, in consumer products and provide a best estimate of goods that are likely to contain BDE-209 in Australia. This review is part of a larger study, which will include quantitative testing of items to assess for BDE-209. The findings of this desktop review will be used to determine which items should be prioritized for quantitative testing. We identified that electronics, particularly televisions, computers, small household appliances and power boards, were the items that were most likely to contain BDE-209 in Australia. Further testing of these items should include items of various ages. Several other items were identified as high priority for future testing, including transport vehicles, building materials and textiles in non-domestic settings. The findings from this study will aid in the development of appropriate policies, should listing of c-decaBDE on the Stockholm Convention and Australias ratification of that listing proceed.

Medium-Chain Chlorinated Paraffins (CPs) Dominate in Australian Sewage Sludge

To simultaneously quantify and profile the complex mixture of short-, median-, and long-chain CPs (SCCPs, MCCPs, and LCCPs) in Australian sewage sludge, we applied and further validated a recently developed novel instrumental technique, using quadrupole time-of-flight high resolution mass spectrometry running in the negative atmospheric pressure chemical ionization mode (APCI-qTOF-HRMS). Without using an analytical column the cleaned extracts were directly injected into the qTOF-HRMS followed by quantification of the CPs by a mathematical algorithm. The recoveries of the four SCCP, MCCP and LCCP-spiked sewage sludge samples ranged from 86 to 123%. This APCI-qTOF-HRMS method is a fast and promising technique for routinely measuring SCCPs, MCCPs, and LCCPs in sewage sludge. Australian sewage sludge was dominated by MCCPs with concentrations ranging from 542 to 3645 ng/g dry weight (dw). Lower SCCPs concentrations (<57–1421 ng/g dw) were detected in the Australian sewage sludge, which were comparable with the LCCPs concentrations (116–960 ng/g dw). This is the first time that CPs were reported in Australian sewage sludge. The results of this study gives a first impression on the distribution of the SCCPs, MCCPs, and LCCPs in Australia wastewater treatment plants (WWTPs).