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Dieses Dokument ist Teil der Anfrage „Zwischenergebnisse und Empfehlungen der BfR-MEAL-Studie“
Determination of water-soluble arsenic species in the BfR MEAL Study Christin Hackethal, Johannes Kopp, Tanja Schwerdtle, Oliver Lindtner 33 As arsenic 74,92160 Step 2 Step 3 Step 4 Step 1 Step 5 Step 6 Bundesinstitut für Risikobewertung
Background - Aim of the BfR MEAL Study Exposure Toxicological Health risk assessment characterisation assessment Concentration Consumption Nutrition- As based exposure Body weight Christin Hackethal, 28.10.2019, AK-Schwerdtle, Universität Potsdam 2
Background - Pathways Christin Hackethal, 28.10.2019, AK-Schwerdtle, Universität Potsdam 3
Background - Occurence & toxic potential Aquatic food toAs Terrestrial food iAs AsB DMA, MMA Arsenate (As(V)) Arsenobetaine (AsB) toxicity Arsenite (As(III)) Monomethyl arsonic acid (MMA) Dimethyl arsinic acid (DMA) ➢IARC Gr. 1 – cancerogenic ➢VO (EU) 2015/1006 Christin Hackethal, 28.10.2019, AK-Schwerdtle, Universität Potsdam 4
Background - Criteria for sample selection Concept of the BfR MEAL Recommendation of expert group Study Rice & rice-based Foods with higher products Aquatic food toAs content & mushrooms mushrooms cucumber linseed … 14 samples 39 samples 40 samples Christin Hackethal, 28.10.2019, AK-Schwerdtle, Universität Potsdam 5
Analysis (I) Pooled TFA / H2O2 Determination of total arsenic in the sample pooled samples using ICP-MS/MS after microwave digestion 15 min, 6.000 rpm Ultrasonic bath 15 min, 35 °C Sample preparation based on Raber et al. (Karl-Franzens-University Graz) Transfer aliquot 60 min, 95 °C Determination of total arsenic in the extracts using ICP-MS/MS after microwave digestion Ultrasonic bath (extraction efficiency) 15 min, 35 °C 15 min, 15.000 rpm Christin Hackethal, 28.10.2019, AK-Schwerdtle, Universität Potsdam 6
Analysis (II) Determination of total arsenic in the Preliminary tests (various buffers, pooled samples using molarities, gradients and isocratic ICP-MS/MS after microwave digestion parameters) Determination of water-soluble Sample preparation based on Raber arsenic species using anion et al. (Karl-Franzens-University Graz) exchange HPLC-ICP-MS/MS Determination of total arsenic in the Identification of arsenobetaine extracts using using cation exchange HPLC-ICP- ICP-MS/MS after microwave digestion MS/MS (extraction efficiency) Christin Hackethal, 28.10.2019, AK-Schwerdtle, Universität Potsdam 7
Results - Rice and rice-based products (I) Intensity m/z (75→91) [counts] 5000 DMA As(V) 4500 4000 3500 3000 Standard 2,5 µg/L 2500 MMA 2000 Rice wafers 1500 Rice 1000 500 0 0 1 2 3 4 5 6 Retention time [min] Table 1: Arsenic content (µg/kg) of selected rice and rice-based products (mean ± SD; n=2) Sub- Pooled sample toAs sample toAs extract DMA iAs ∑ As-Sp samples (n) Rice (organic) 15 39 ± 3 45 ± 2 1±1 33 ± 2 34 ± 2 Rice (conventional) 15 46 ± 6 = 115/2.8 36 ± 2 = 41 8±1 33 ± 1 41 ± 1 Rice wafers (organic) 15 115 ± 6 106 ± 1 14 ± 1 88 ± 1 102 ± 1 Rice wafers (conventional) 15 130* = 130/2.8 125 ± 2 = 46 19 ± 1 106 ± 5 125 ± 5 Rice pudding (organic) 15 30 ± 1 36 ± 2 4±3 24 ± 6 38 ± 1 Rice pudding (conventional) 15 22* 21 ± 1 = 130/10 = 13 7 ± 1 18 ± 3 25 ± 1 Oats (conventional) 15 12 ± 1 not analyzed * n = 1 (single determination) Christin Hackethal, 28.10.2019, AK-Schwerdtle, Universität Potsdam 8
Results - Rice and rice-based products (II) Table 1: Arsenic content (µg/kg) of selected rice and rice-based products (mean ± SD; n=2) Sub- Pooled sample toAs sample toAs extract DMA iAs ∑ As-Sp samples (n) Rice (organic) 15 39 ± 3 45 ± 2 1±1 33 ± 2 34 ± 2 Rice (conventional) 15 46 ± 6 36 ± 2 8±1 33 ± 1 41 ± 1 Rice wafers (organic) 15 115 ± 6 106 ± 1 14 ± 1 88 ± 1 102 ± 1 Rice wafers (conventional) 15 130* 125 ± 2 19 ± 1 106 ± 5 125 ± 5 Rice pudding (organic) 15 3±1 36 ± 2 14 ± 3 24 ± 6 38 ± 1 Rice pudding (conventional) 15 22* 21 ± 1 7±1 18 ± 3 25 ± 1 * n = 1 (single determination) Regulation (EC) No. 2015/1006 mg/kg Christin Hackethal, 28.10.2019, AK-Schwerdtle, Universität Potsdam 9
Results - Rice and rice-based products (III) Consideration of ingredients Intensity m/z (75→91) [counts] Rice-based mixed meals Shrimps (scaled: intensity/50) Shrimps Rice-based meals with vegetables Rice 700 DMA As(V) 1950 As(V) Intensity m/z (75→91) [counts] 600 AsB 1750 1550 DMA 500 1350 400 1150 300 950 750 200 550 100 350 0 150 0 1 2 3 4 5 6 0 1 2 3 4 5 6 Retention time [min] Retention time [min] Table 2: Arsenic content (µg/kg) of rice-based composite dishes (mean ± SD; n=2) Sub- Pooled sample toAs sample toAs extract DMA iAs AsB ∑ As-Sp samples (n) Rice-based meals with vegetables 20 30* 36 ± 2 8±1 31 ± 1 ND 39 ± 1 Rice-based mixed meals 20 48 ± 2 54 ± 2 16 ± 1 27 ± 3 8±1 51 ± 4 * n = 1 (single determination) Christin Hackethal, 28.10.2019, AK-Schwerdtle, Universität Potsdam 10