Prof. Gang Yu, Yinping Zhang, Zhiguo Cao 2 September, 2013

1. Tsinghua University’s Activities Related to Prof.GangYu,YinpingZhang,ZhiguoCao 2 September, 2013

2. ActivitiesinSchoolofEnvironment • Outward Secondments • Inward secondments • Relatedresearch • Outputs

3. 1.OutwardSecondments • Tsinghua coverInternational traveltickets by other projects

4. 2.InwardSecondments • Tsinghua provides office and small materials by other projects

5. 3.RelatedResearch • ZhiguoCao: Environmental behavior of BFRs in indoor dust and uncertainty analysis for human exposure in China • MinWu: Environmental behavior of NBFRs in indoor dust in China • WencaoLi: Analytical method of BFRs/NBFRs in environmental samples

6. 4.Outputs • Journal paper • TU and UA: preparing • Conference presentation • BFR 2013 • Dioxin 2013

7. Secondment between TU-AU/UB Zhiguo Cao, Min Wu POPs Research Center, School of Environment, Tsinghua University, China

8. Secondment between TU-AU: A report based on our experiment Zhiguo Cao1,*, Fuchao Xu2, Gang Yu1, Adrian Covaci2 1POPs Research Center, School of Environment, Tsinghua University, China 2Toxicological Centre, University of Antwerp, Belgium

9. Sample determination • A multi-residue method for simultaneous determination of PBDEs, NBFRs and PFRs were used in this study. • 26BFRs, 12PFRs were analysed. • Method accuracy and precision was evaluated by replicate (n=11) analysis of NIST SRM 2585 (organics in indoor dust). • Totally, 166 samples were analysed in ANTERWERP University during two months. Talanta 89 (2012) 292– 300

10. Part 1. Within-building seasonal and spatial variations in concentrations of selected BFRs and PFRs in indoor dust • Part 2. Particle size distribution of BFRs and PFRs in different kinds of indoor dust

11. Part 1. Within-building seasonal and spatial variations in concentrations of selected BFRs and PFRs in indoor dust

12. Motivation • To date, very limited information is available about the variability of concentrations of PBDEs, and especially for NBFRs and PFRs in dust over time. • How will concentrations of FRs change in indoor matrix over time? Months, Seasons of Years? • As a result, we conducted this study to investigate the seasonal variation patterns in concentrations of selected BFRs and PFRs in office dust from Beijing.

13. Sampling informations For this study, three offices were selected in one building located in Beijing, China. We want to know if the concentration of FRs in indoor environment will be influenced by the seasonal change.

14. Sample preparation • Samples were collected directly from their office-hold vacuum bags, around 20, 120, 100 gram dust can be sampled each time. • After sampling, the vacuum bags will be cleaned with water and dryed in the sun. • All the samples were sieved with a stainless mesh to collect particles <2 mm in size, from which about 10 g samples were further packed with aluminium foil and sealed in clean polyethylene zip bags and stored in the dark at −20 ℃. • 9PBDEs, 4NBFRs and 9PFRs were commonly detected.

15. Results and discussion

16. General concentrations and profiles • In agreement with the literature, the results of the present study show that the levels of PFRs in the indoor environment are usually higher than those of other BFRs. • Concentrations of OPFRs and NBFRs in Office A were higher than that in Office B and C, while levels of PBDEs in Office A were extremely low (554 ng/g). Mean concentration of PFRs in Office A was 128, 000 ng/g, which is a very high value compared with data from the literature. • For the profiles, PFRs were the dominant components of all three groups of FRs, especially for Office A, the foreign company. • Concentrations and profiles of PBDEs, NBFRs and PFRs were similar for the two domestic corporations. PBDEs still account for inconvenient proportions. • Based on the above analysis, it’s concluded that PBDEs have been phased out and substituted by NBFRs and PFRs in Office A, the foreign company, and for the domestic offices, PBDEs still need to be baned in the future. On the other hand, it is clear that Office A perform more strict and developed standard of flame retardents.

17. Detailed profiles of PBDEs, NBFRs and PFRs • For PBDEs, deca BDE was the dominant compound in Office A, which might be the historical residues; while in Office B and C, though deca BDE is dominant, penta BDE, which have been banned in some countries, also accounted for important proportions. • For NBFRs, in Office A, BTBPE, the alternative of octa BDE, was the most important component; while in Office B and C, DBDPE, the alternative of deca BDE, was the largest constituent. As alternatives of penta BDEs, TBPH was a small contributor but the percentage of TBB is even negligible. • For PFRs, TCPP had the dominant contribution in Office A; with more complicated profiles, TCPP, TBEP and TpHP are the three abundant components for Office B and C.

18. Seasonal concentration variations of sum FRs • Concentrations of PBDEs and NBFRs keep constant during the monitoring duration. • A more clear trend was found for the temporal variability in concentrations of PFRs. Obviously, PFR concentrations were the highest in winter, followed by autumn and that in summer were the lowest. Higher indoor temperatureswill result in increased partitioning of SVOCsto air, and PFRs are more volatile compared with PBDEs and NBFRs. 4-Mar 2012 23-Dec • The ranges of concentrations (∑PBDEs and ∑NBFRs) detected in the three offices were substantial. This indicates that when a dust sample is taken can influence the concentrations of BFRs detected.

19. Seasonal profile variation • Taking BDE47, 99, 209, TBPH, BTBPE, DBDPE, TCPP, TBEP and TPhP as the dominant constituents, the seasonal profile variations of PBDEs, NBFRs and PFRs are illustrated in the Figure. • In Office A, the profiles of PBDEs, NBFRs and PFRs show good consistency. While in Office B and C, the profiles of PBDEs and PFRs reveal some variations.

20. Conclusions • Within the same building, big differences were found between Office A and Office B&C on FR concentrations and profiles. • PFRs were the dominated components of all the three kinds of FRs, especially for Office A, the foreign company. Different substitutional relationships were discovered in these offices. • Seasonal changedoes show marked impact on OPFR contamination in dust, with the abundance rank order as: winter>autumn>summer; but the opposite was observed for BFRs.

21. Part 2: Preliminary data report Particle size distribution of BFRs and PFRs in different kinds of indoor dust

22. Sample information

23. Particle size distribution of dust <500 um Fraction profiles of the dust samples in this study Particles <50 um were fractionated into 5 fractions (F9-13) further with sedimentation method.

24. Laser Particle Size Analyzer

25. Concentrations and patterns General concentrations and profiles of BFRs in fractions <50 um

26. General concentrations and profiles of PFRs in fractions <50 um

28. Based on these data, two or three papers can be published.

29. Secondment between TU-UB: A report based on Min Wu’s work

30. Technology transfer from UB to TU Analysis of NBFRs and OPFRs in dust

31. Analysis of NBFRs and OPFRs in dust-Introduction IS Dust sample Extraction Clean-up Instrument Data Weighing the dust and adding internal standards Adding extract solvent (2 ml Hex : Ace, 3 : 1, v : v) Vortexing for 1 min Ultrasonication for 10 min Vortexing for 1 min Centrifuging for 2 min Collecting the supernatants Combining and evaporating extracts Redissolving extracts in 1 ml Hex One cycle, repeat 3 times

32. Analysis of NBFRs and OPFRs in dust-Introduction Pre-cleaning Florisil cartridges Transferring extracts to cartridges Eluting of NBFRs with 10 ml Hex (F1) Eluting of OPFRs with 8 ml EtAc (F2) Evaporating and redissolving of F2 Evaporating and transferring F1 to acid silica gel cartridges Eluting with 10 ml Hex : DCM (1 : 1, v : v) Evaporating and redissolving of F1 GC-MS

33. Analysis of NBFRs and OPFRs in dust-Validation Spiked sample (n=3) Na2SO4/dust Before extraction Spiked sample (n=3) Na2SO4/dust Before Injection Non-spiked sample (n=3) Blanks + + One Batch Repeat 3 times (n=3) Spiking experiments The instrumental results are in progress……

34. Thank you!