Conference Contribution Details
Mandatory Fields
N. Wemken, M. Coggins, D. Drage, M. Abdallah, S. Harrad
8th International Symposium on Flame Retardants
Elucidating Levels and Pathways of Human Exposure in Ireland to POP-BFRs (ELEVATE)
York, UK
Refereed Abstracts
Optional Fields
08-MAY-17
10-MAY-17
Introduction As a signatory of the UNEP Stockholm Convention on persistent organic pollutants (POPs), the Irish government is required to eliminate or restrict the use and release to the environment of POPs in Ireland. Among the POPs covered by the Convention are a number of brominated flame retardants (BFRs) [1]. Such BFRs, namely Hexabromocyclododecane (HBCDD) and polybrominated diphenyl ethers (PBDEs) (collectively referred to here as POP-BFRs) were used as flame retardants in a variety of soft furnishings, building insulation foams, electronic and electrical goods. To characterise human exposure to these contaminants bio-monitoring studies[2,3,4] coupled with environmental measurements in food, household dust and air have been conducted in numerous countries[3,4,5,6]. Previous human bio-monitoring data in Ireland and information regarding concentrations in foodstuffs suggests that exposures to these contaminants in Ireland are ow[2,8,9,10,11]. However, there is a dearth of data on concentrations of BFRs in indoor air and dust in different microenvironments within Ireland, information required to fully understand both the overall magnitude of exposure and the relative contributions of different exposure pathways. ELEVATE Project Objectives The ELEVATE project will conduct the first study of levels of BFRs (tri- through deca-PBDEs, and a-, b-, and g-HBCDD) in indoor air and dust in common Irish Microenvironments (homes, cars, primary schools and offices). Data will be combined with existing data on concentrations in the Irish diet to evaluate the relative contribution of the different exposure pathways. A human biomonitoring study will also be carried out (by analysing human milk samples) to provide information on body burdens in the Irish population. Comparison with a previous such study will facilitate assessment of the impact on body burdens of restrictions on the manufacture and use of these chemicals. Specific project objectives are to: Evaluate the relative contributions of different exposure pathways (diet, indoor air and dust) to POP-BFRs in Ireland Establish the current body burdens of POP-BFRs in the Irish population and by comparison with previous biomonitoring data in Ireland, assess the impact of recent restrictions on the manufacture and use of these contaminants Evaluate the relationships between external and internal exposure of the Irish population to POP-BFRs using simple one compartment pharmacokinetic models. Materials and Methods Exposure Assessment Approximately 32 samples each of air, dust and tap water have been collected from Irish microenvironments such as homes, cars, primary schools and offices between August 2016 and January 2017 (Table 1). Air samples have been collected by deploying passive PUF disk air samplers 2 for 60 days and dust samples were collected by vacuuming floors following methods previously described by Abdallah and Harrad[11] and Goosey and Harrad [12] respectively. Table 1. Sample Collection. 32 air, dust and water samples have been collected from microenvironments in Dublin, Galway and Limerick. Biomonitoring Study Human breast milk samples will be procured from 110 first time mothers (primiparas) via University Hospital Galway and the Coombe Women and Infants University Hospital, Dublin following protocols outlined in a previous Irish biomonitoring study [2,13]. Samples will be pooled to provide 10 samples which will be analysed for concentrations of PBDEs and HBCDD at the University of Birmingham following previously validated methods[3,4,14]. Results will be used to assess current body burdens of the Irish population and - by comparison with the aforementioned previous Irish human milk study evaluate evidence for any temporal trend in body burdens of POP-BFRs in Ireland. Chemical analysis Sample analysis is due to commence in March 2017; air and dust samples will be analysed for concentrations of PBDEs and HBCDD at the University of Birmingham using validated in house methods[15,16,17,18]. Aliquots (~100 mg) of dust will be transferred to 66 mL Accelerated Solvent Extractor (ASE) cells, prepacked with a glass fibre filter (GFF) and clean hydromatrix. Sampling components of the passive air samplers (PUF and GFF) will be transferred to 66 mL ASE cells. Samples will be spiked with a known quantity of internal standard (BDE-77, BDE-128, 13C12-BDE-209, 13C12-α-HBCDD, 13C12-β-HBCDD and 13C12-γ-HBCDD). Samples will be extracted using pressurized liquid extraction (PLE), using hexane:DCM (3:2, v/v ratio) as the extractions solvent. Extracts will be concentrated to ~1 mL using a Turbovap II concentration evaporator and washed with >95% concentrated sulfuric acid, before further purification on a florisil SPE cartridge. Clean extracts will be concentrated to 200 μL iso-octane and transferred to auto sampler vials for analysis of PBDEs via GC-EI/MS. Extracts will then be solvent exchanged into methanol and analysed for HBCDD on LC-MS/MS. Data Analysis An assessment of the Irish population exposure to POP-BFRs will be calculated and information collated. A one compartment pharmacokinetic model will be developed based on previous models[3,4,19] to examine relationships between external and internal exposure of the Irish population Microenvironments Type of sample 32 homes Air 32 cars Dust 32 offices 32 schools Water 3 to POP-BFRs. Moreover, we will incorporate recent information about dermal exposure to PBDEs and HBCDDs present in indoor dust[20,21], and via sensitivity analysis evaluate the relative impact of individual input parameters on model outputs. Expected project results: Preliminary project data will be available in May 2017, the ELEVATE research project will generate the following outcomes in relation to human exposure to PBDEs and HBCDDs in Ireland; The first measurements of POP-BFRs in indoor air and dust in Irish microenvironments. Information on the relative contribution of different exposure pathways to current body burdens of the Irish population. Biomonitoring data which can be used to establish the current body burdens of these contaminants in the Irish population, as well as an estimate of the dietary intake of nursing infants. An assessment of the impact of recent legislative restrictions on the manufacture and use of POP-BFRs, by comparing results from ELEVATE with results from those determined in previous Irish biomonitoring studies. Acknowledgement ELEVATE is funded by the Environmental Protection Agency of Ireland (Grant 2015-HW-MS-4). References: [1] UNEP- Stockholm, Convention, http://chm.pops.int/TheConvention/Overview/TextoftheConvention/tabid/2232/Default.aspx, accessed 21.10.16; [2] Pratt, I. et al (2013) Food Addit. & Contam. Part A, 30:1788-1798; [3] Abdallah, M. & Harrad, S. (2014) Environ. Int. 63:130-136; [4] Abdallah, M. & Harrad, S. (2011) Environ. Int. 37:443-448; [5] Trudel, D. et al. (2011) Environ. Sci. and Technol., 45:2391-2397; [6] Lorber, M. (2008) J. Expo. Sci. Environ. Epidemiol. 18:2-19; [7] FSAI (2013) Dioxins, Furans, Polychlorinated Biphenyls and Brominated Flame Retardants in Fishery Products in Ireland; [8] FSAI (2010) Investigation into levels of perfluoroalkylated substances (PFAS) in meat, offal, fish, eggs, milk and processed products; [9] FSAI (2005) Investigation into levels of dioxins, furans, PCBs and PBDEs in food supplements, offal and milk; [10] FSAI (2004) Investigation into levels of dioxins, furans, PCBs and PBDEs in Irish Food 2004; [11] Abdallah, M. & Harrad, S. (2010) Environ. Sci. and Technol. 44:3059-3065; [12] Harrad, S. et al (2008) Environ. Int., 34:11701175; [13] Pratt, I. et al (2012) Chemosphere, 88: 865-872; [14] Tao, L. et al (2008) Environ. Sci. and Technol. 42:8597-8602; [15] Goosey, E., Harrad, S. (2011) Environ. Int., 37:86-92; [16] Goosey, E., Harrad, S. (2012) Environ. Int., 45:86-90; [17] Abdallah, M. & Harrad, S. (2008) Environ. Sci. and Technol. 42:459-464; 4 [18] Abdallah, M. & Harrad, S. (2009) Anal. Chem., 81:7460-7467; [19] Thompson, J. et al (2010) Environ. Int., 36:390397; [20] Pawar, G. et al (2017) J. Expo. Sci. Environ. Epidemiol, 27:100-105; [21] Abdallah, M. et al (2015) Environ. Sci. and Technol. 49:10976-10983.
Publication Themes
Environment, Marine and Energy