第一部分的研究中主要是對於羊栖菜及食用米中的無機砷物種進行分析，砷元素會以不同物種型態存在著，而不同物種其毒性也不同，而砷化物目前仍廣泛地應用於工業上，若發生不慎外漏情形或廢棄物處理不當而進入環境當中，有可能會經由食物鏈進入生物體中，而發生生物累積效應而危害人體，此次本篇研究是使用陰離子交換樹脂層析法結合(Anion-exchang chromatography)結合ICP-MS分別對於羊栖菜及食用米中砷物種進行分析研究，並使用超純水搭配微波輔助萃取法對羊栖菜進行萃取，其無機砷物種萃取效率近乎100%，本實驗系統在最適化條件下能夠在6分鐘內分離2個無機砷物種及4種有機砷物種，波峰面積及高度皆小於5.6%，偵測極限0.005-0.008 ng mL-1。並將本方法應用於NMIJ CRM 7405-a羊栖菜標準參考樣品及SRM 1568a Rice Flour標準參考樣品，以證明方法的準確性及可行性，最後對於2個市售羊栖菜及2種市售食用米進行測定。
第二部分研究主要是陰離子交換樹脂層析搭配化學蒸氣生成系統，對於TMAO、As(III)、DMA、MMA及As(V)五個砷物種進行物種分析，沖提方式為使用梯度沖提，為得到適當之分析時間及訊號， 將HPLC與CVG系統串連後依序對pH值與相關試劑作探討，並將分離後的砷物種經由化學蒸氣生成(Chemical vapor generator，CVG)系統產生砷之氫化物，搭配氣動式霧化器做為氣液分離裝置，藉此提升砷物種在ICP-MS中的感度，由於系統中使用HCl當作酸化試劑，而Cl會與Ar形成ArCl+造成多原子同質量光譜干擾，在此需要使用動態反應槽(Dynamic reaction cell，DRC) 模式達到去除此光譜干擾之效果，藉此得到較低的偵測極限。並且最後將HPLC-CVG-DRC-ICP-MS 系統應用於食用米真實樣品中。

In the first study, we assess the inorganic arsenic species content in seaweed and rice. The determination of arsenic species have bee used ion exchange chromatography on an anion exchange column with inductively coupled plasma mass spectrometry detection after microwave assisted extraction. The arsenic species studied were arsenite [As(III)], arsenate [As(V)], monomethylarsonic acid (MMA), dimethylarsonic acid (DMA), arsenobetaine (AsB) and arsenocholine (AsC). Chromatographic separation of all the species was achieved 6 min in gradient elution mode using (NH4)2CO3 and methanol at pH 8.5. The recovery of inorganic arsenic species with using ultra-pure water in seaweeds were up to 100%. The limits of detection were in the range of 0.005-0.008 ng mL-1 for various arsenic species based on peak area.
In the Second study is a method employing a chemical vapor generation system and LC combines with inductively coupled plasma mass spectrometry (CVG-LC-ICP-MS) is presented for the determination of arsenic species in rice sample. To get best signal, we have tested concentration of L-cysteine, HCl and NaBH4. Because we have used HCl as acidifying agent. To avoid 40Ar35Cl interferes with 75As, we choose O2 as collision gas in DRC system to aviod polyatomic ions 40Ar35Cl + and get the lower detection limit.The accuracy of the method is evaluated by analyzing by analyzing rice flour certified reference material (SRM 1568a).The method has been applied on rice sample.

目錄
論文審定書………………………………………………………………………....………. i
誌謝…………………………………….………………………………………………… ii
摘要…………………………………………………………………………........…… .iii
Abstract…………………………………………………………………………………… v
目錄………………………………………………………………………………………. vi
圖目錄 …………………………………………………………………………………...viii
表目錄 …………………………………………………………………………………….ix

第一章　液相層析結合感應耦合電漿質譜儀於海藻及食用米中無機砷物種之分析
壹、前言
貳、實驗部分
一、儀器裝置…………………………………………………………………...……5
二、藥品與溶液的配製………………………………………………………...……6
參、實驗過程
一、液相層析分離條件的探討……………………………………………….9
二、再現性……………………………………………..………………………………..9
三、校正曲線與偵測極限……………………...……………………………..……….9
四、萃取條件最適化…………………………………………………………………10
五、真實樣品分析…………………………………………………………….11
肆、結果與討論
一、液相層析條件最適化探討………………………………………………………..14
二、再現性……………………………………………………………………………27
三、校正曲線與偵測極限……………………………………………..………………27
四、萃取條件最適化……………………………..…………………………………27
五、真實樣品分析……………………………………………………………………37
伍、結論…………………………………………………………………………………..48
陸、參考文獻..…………………………………………………………..………………..49
第二章　液相層析結合化學蒸氣生成感應耦合電漿質譜儀於食用米中砷物種之
　　　　分析
壹、 前言
一、研究背景…………………….............……………………………………………53
二、化學蒸氣生成法………………………………………………………………..54
三、動態反應槽………………………………………………………………………..55
貳、實驗部分
一、儀器裝置……………………………………………………………………........56
二、藥品與溶液的配製..................................................................................................57
參、實驗過程
一、液相層析分離條件的探討……………………………………………….……….58
二、化學蒸氣生成系統條件探討 ……………………..……………………………..60
三、ICP-MS系統操作條件探討……………….……………………………..……….60
四、萃取條件最適化…………………………………………………………..………61
五、真實樣品分析……………………………………………………………….…….61

肆、結果與討論
一、液相層析分離條件的探討......................................................................................62
二、化學蒸氣生成系統操作條件的最適化..................................................................65
三、ICP系統操作條件的最適化...................................................................................74
四、DRC系統條件最適化探討.....................................................................................74
五、再現性……..............................................................................................................83
六、校正曲線與偵測極限..............................................................................................83
七、真實樣品分析…………………………………………………………………….88
伍、結論.....................................................................................................................89
陸、參考文獻.............................................................................................................90



圖目錄
第一章 液相層析儀結合感應耦合電漿質譜儀於海藻及食用米中無機砷物種分析
圖1-1 HPLC-ICP-MS 之系統示意圖…..………………………………….........6
圖1-2 各種砷物種之結構式……………………………………………………..10
圖1-3 各種砷物種於不同pH值環境下之化學式及pKa值…………………….10
圖1-4 實驗流程圖……………………………………...……………………….12
圖1-5 樣品萃取流程圖…………………………………………………….……13
圖1-6 砷物種在pH值下之表徵電荷變化量……………………..……………17
圖1-7 改變動相pH值對層析分離的影響……………………………………..19
圖1-8 改變動相B中碳酸銨濃度對層析分離的影響…………………...……..20
圖1-9 改變動相中甲醇濃度對層析分離的影響……………………….……….21
圖1-10 改變動相A之碳酸銨濃度對層析分離之影響………………………….22
圖1-11 改變動相切換時間對層析分離之影響……………..……………………24
圖1-12 改變動相ramp時間對層析分離之影響……………..………………….25
圖1-13 不同萃取溫度於羊栖菜中砷萃取量之相對訊號……………………….32
圖1-14 不同萃取時間於羊栖菜中砷萃取量之相對訊號………………………..33
圖1-15 以不同濃度之硝酸萃取食用米之萃取效率…………………….……….35
圖1-16 以不同濃度之硝酸萃取食用米之萃取效率……………………………..36
圖1-17 NMIJ CRM 7405-a羊栖菜標準品之萃取層析圖……………….……….40
圖1-18 百貨公司羊栖菜標準品之萃取層析圖…………………………….…….41
圖1-19 年貨大街羊栖菜標準品之萃取層析圖………………………….……….42
圖1-20 為標準參考樣品SRM 1568a Rice Flour萃取所得之層析圖.…….….….44
圖1-21 市售食用米# 1萃取所得之層析圖………………………………..…..….45
圖1-22 市售食用米# 2萃取所得之層析圖……………………………………….46

第二章　液相層析化學蒸氣生成技術結合感應耦合電漿質譜儀於食用米中砷物種之分析
圖2-1 HPLC-CV-ICP-MS之系統裝置圖..............................................................59圖2-2 探討陰離子交換管柱長度對層析時間之影響..........................................64
圖2-3 探討動相A、B之pH值對層析分離影響....................................................65
圖2-4 探討動相B濃度柱對層析及氫化物生成效果的影響..............................67
圖2-5 探討動相之甲醇濃度對氫化物生成效果的影響......................................68
圖2-6 探討NaBH4濃度對砷物種的影響..............................................................70
圖2-7 探討L-cysteine濃度對砷物種的影響........................................................72
圖2-8 探討HCl濃度對砷物種的影響..................................................................73
圖2-9 探討混合線圈體積對砷物種的影響..........................................................74
圖2-10 探討霧化氣體流速對砷物種的影響…......................................................76
圖2-11 以O2為反應氣體改變氣體流速對砷物種的影響.....................................78
圖2-12 以H2為反應氣體改變氣體流速對砷物種的影響…………....................79
圖2-13 以O2為反應氣體改變Rpq對砷物種的影響………….............................80
圖2-14 以H2為反應氣體改變Rpq對砷物種的影響…….....................................81
圖2-15 以O2為反應氣體改變AFV對砷物種的影響............................................82
圖2-16 以H2為反應氣體改變AFV的砷物種的影響…………............................83
表目錄
第一章 液相層析儀結合感應耦合電漿質譜儀於海藻及食用米中無機砷物種分析
表1-1 各種含砷化合物之LD50……………………….………………...………....9
表1-2 微波輔助萃取升溫程式…………………………………………………..13
表1-3 微波輔助萃取升溫程式.………………………………….....…………..13
表1-4 動相A中碳酸銨濃度對1 ng mL-1分析物訊號影響……..…………...….23
表1-5 HPLC-ICP-MS系統操作條件………….....................................................26
表1-6 HPLC-ICP-MS測定5 ng mL-1砷物種之滯留時間與分析訊號再現性…28
表1-7 砷物種水溶液校正曲線及偵測極限…………………………….……….29
表1-8 砷物種偵測極限之比較……………………………………….….………30
表1-9 HPLC-ICP-MS測定羊栖菜中砷物種之含量………………………....….39
表1-10 HPLC-ICP-MS測定食用米真實樣品中砷物種之含量…………...……..43
表1-12 比較各研究中，NIST 1568a Rice Flour中砷物種之含量……………….47

第二章　液相層析結合化學蒸氣生成感應耦合電漿質譜儀於食用米中砷物種
　　　　分析
表2-1 HPLC-CVG-DRC-ICP-MS 系統之最適化條件........................................85
表2-2 砷物種滯留時間與分析訊號之再現性......................................................86
表2-3 砷物種水溶液校正曲線及偵測極限..........................................................87
表2-4 砷物種偵測極限之比較..............................................................................88
表2-5 比較各研究中，NIST 1568a Rice Flour中砷物種之含量................................90
表2-6 LC-CV-ICP-MS 與其他分析方法之比較......................................................91

一、液相層析結合感應耦合電漿質譜儀於海藻及食用米中無機砷物種之分析應用
1. Qi, Y. O.; Donahoe, R. J. The environmental fate of arsenic in surface soil contaminated by historical herbicide application. Sci. Total Environ. 2008, 405, 246-253.
2. Moreira, C. M.; Duarte, F. A.;Lebherz, J.;Pozebon, D.;Flores, E. M. M. Arsenic speciation in white wine by LC-ICP-MS. Food Chem. 2011, 126, 1406-1411.0
3. Michalski, R.; Szopa, S.; Jablonska, M.; Lyko, A. Application of hyphenated techniques in speciation analysis of arsenic, antimony, and thallium. Sci. World J. 2012, 305, 1-17.
4. Yu, H. S.; Liao, W. T.; Chai, C. Y. Arsenic carcinogenesis in the skin. J Biomed Sci. 2006, 13, 657-666.
5. Tsai, S. M.; Wang, T. N.; Ko, Y. C. Mortality for certain diseases in areas with high levels of arsenic in drinking water. Arch Environ Health 1999, 54, 186-193.
6. Yang, G.; Xuan, C.; Lee, F. S.; Wang, X. R. Determination of arsenic and it’s species in dry seafood by high performance liquid chromatography inductively coupled plasma mass spectrometry. Anal Chem.2009, 37, 1738-1750.
7. Pizazzo, I.; Gomez, M.; Camara, C.; Palacios, M. A. Arsenic speciation in environmental and biological samples-Extraction and stability studies. Anal. Chim. Acta. 2003, 495, 85-98
8. Yan, X. P.; Ni, Z. M. Vapour generation atomic absorption spectrometry. Anal. Chim. Acta 1994, 291, 89-105
9. 中華民國102年08月21日部受食字1021350295號令修正 藻類食品衛生標準.
10. Dressler, V. L.; Moreira, C. M.; Duarte, F. A.;Lebherz, J.; Pozebon, D.; Flores, E. M. M. Arsemic speciationin in white wine by LC-ICP-MS. Food Chem. 2011, 126, 1406-1411.
11. Cheng, H.; Liu, X.; Zhang, W.; Hu, Y. Extraction and detection of organoarsenic feed additives and common arsenic species in environmental matrices by HPLC-ICP-MS. Microchem. J. 2013, 108, 38-45.
12. Heitlaland P.; Koster, H. D. Comparison of different medical cases in urinary arsenic speciation by fast HPLC-ICP-MS. Int. J. Hyg. Environ. Health 2009, 212, 432-438.
13. Hsieh, Y. J.; Jaing, S. J. Application of HPLC-ICP-MS and HPLC-ESI-MS procedures for arsenic speciation in seaweeds. J. Agric. Food Chem. 2012, 60, 2083-2088.
14. Slejkovec, Z.; Johannes E.; Byrne, A. R.; Goei, J. J. M. Separation of radiolabelled arsenic compounds produced by neutron irradiation of organoarsenic compounds. Anal. Chim. Acta 1999, 380, 63-71.
15. Suner, M. A.; Devesa, V.; Munoz, O.; Velez, D.; Montoro, R. Application of column swiching in high-performance liquid chromatography with on-line thermo-oxidation and detection by HG-AAS and HG –AFS for the analysis of organoarsenical species in seafood samples. J. Anal. At. Spectrom.2001, 16, 390-397.
16. Zheng, J.; Goessler, W.; Kosmus, W. The chromatographic behavior of arsenic compounds on anion exchang colums with binary organic acids as mobile phases. Chromatographia. 1998, 47, 257-263.
17. Styblo, M.; Hughes, M. F.; Thomas, D. J., Liberation and analysis of protein-bound arsenicals. J. Chromatogr. 1996, 677, 161-166.
18. Wangkarn, S.; Pergantis, A. S., High-speed separation of arsenic compounds using narrow-bore high-performance liquid chromatography on-line with inductively coupled plasa mass spectrometry. J Anal. At. Spectrom. 2000, 15, 527-533.
19. Raber, G.; Raml, R.; Gosessler, W.; Francesconi, K. A. Quantitative speciation of arsenic compounds when using organic solvent gradients in HPLC-ICP-MS. J. Anal. At. Spectrom. 2010, 25, 570.
20. Lasen, E. H.; Sturup, S. Carbon-enhanced inductively-coupled plasma-ass spectrometric detection of arsenic and selenium and its application to arsenic speciation. J. Anal. At. Spectrom. 1994, 9, 1099-1110.
21. 王孝銘. 液相層析結合化學蒸氣生成感應耦合電漿質譜儀於水樣中砷物種之分析. 國立中山大學, 高雄市, 2013.
22. Liu, L.; He, B.; Yun, Z.; Sun, J.; Jiang, G. Speciation analysis of arsenic compounds by capillary electrophoresis on-line copled with inductively coupled plasma mass spectrometry sing novel interface. J. Chromatogr. A 2013, 1304, 227-234.
23. Chen, B; Hu B.; He M.; Mao, X.; Zu, W., Synthesis of mixed coating with multi-functional groups for in-tube hollow fibersoild phase microextraction-high performance liquid chromatoghraphy-inductively plasma mass spectrometry speciation of arsenic in human urine. J. Chromatogr. A 2012, 1227, 19-27.
24. Leufroy, A.; Noel, L.; Duailly, V.; Beauchemin, D.; Gue’rin, T., Determination of seven arsenic species in seafood by ion exchange chromatography coupled to inductively coupled plasma-mass spectrometry following microwave assisted extraction: Method validation and occurrence data. Talanta 2011, 83, 770-779.
25. Tsai, M. W.; Sun, Y. C.On-line coupling of an ultraviolet titanium dioxide film reactor with a liquid chromatography/hydride generation/inductively coupled plasma mass spectrometry system for continuous determination of dynamic microdialysate samples. Rapid Commum Mass Spectrom. 2008, 22, 211-216.
26. Soeroes, C.; Goessler, W.; Francesconi, A. K.; Kienzl N.; Schaeffer, R.; Foder, P.; Kuehenelt, D. Arsenic speciation in farmed hungarian freshwater fish. J. Agric. Food Chem. 2005, 53, 9238-9246
27. Castillo, A.; Roig-Navarro, A. F.; Pozo, O. J. Capabilities of microbore columns coupled to inductively coupled plasma mass spectrometry in speciation of arsenic and selenium. J. Chromatogr. A 2008, 1202, 132-140.
28. 中華民國104年6月23日修正水產品中無機砷之檢驗方法
29. Pizarro, I.; Gomez, M.; Palacios, M. A.; Camara. C. Evaluation of stability of arsenic species in rice. Anal Bioanal Chem. 2003, 376, 102-109.
30. Kim, J. Y.; Kim, W. I.; Kunhukrishnan, A.; Kang, D. W..; Kim, D. H.; Lee, Y. J.; Kim, Y. J.; Kim, C. T. Determination of arsenic species in rice grains using HPLC-ICP-MS. Food Sci Biotechnol 2013, 22, 1509-1513.
31. Larsen, E. H.; Engman, J.; Sloth, J. J.; Hansen, M.; Jorhem, L. Determination of inorganic arsenic in white fish using microwave-assisted alkaline alcoholic sample dissolution and HPLC-ICP-MS. Anal Bioanal Chem. 2005, 381 339-346
32. Sanz, E.; Munoz-Olivas, R.; Camara, C. A rapid and novel alternative to conventional sample treatment for arsenic speciation in rice using enzymatic ultrasonic probe. Anal. Chim. Acta 2005, 535, 227-235.
33. Li, X.; Xie, K.; Yue, B.; Gong, Y.; Shao, Y.; Shang, X.; Wu, Y. Inorganic sarsemic contamination of rice from Chinese major rice-producing areas and exposure assessment in Chinese population. Science China-Chemistry 2015, 407, 100-107.
34. Zhu, Y. G.; Sun, G. X.; Lei, M.; Teng, M.; Liu, Y. X.; Chen, N. C.; Wang. L. H.; Carey, A. M.; Deacon, C.; Raab A.; Meharg, A. A.; Williams, P. N. High percentage inorganic arsenic content of mining impacted and nonimapcted Chinese rice. Environ Sci Technol. 2008, 42, 5008-5013.
35. Batista, B. L.; Barbosa, F. Speciation of arsenic in rice and estimation of daily intake of different arsenic species by Brazilians through rice consumption. J Hazard Mater 2011, 191, 342-348.
36. D’Amato M,; Forte, G.; Caroli, S. Identification and quantification of major species of arsenic in rice. J AOAC Int. 2004, 87, 238-243.
37. Sanz, E.; Munoz-Olivas, R.; Camara, C.; Sengupta, M. K.; Ahamed, S. Arsenic speciation in rice, straw, soil, hair and nails samples from the arsnic-affected areas of middle and lower Ganga plain. J Environ Sci Health 2007, 42, 1695-1705.
二、液相層析結合化學蒸氣生成感應耦合電漿質譜儀於食用米中砷物種之分析應用
1. Huang, X. H.; Kurata, N.; Wei, X. H.; Wang, Z. X.; Zhao, Q.; Zhao, Y.; Kiu, K. Y.; Lu, H. Y. A map of rice genome variation reveals the origin of cultivated rice. Natrue 2012, 490, 497-503
2. Zavala, Y. J.; Duxbury, J. M. Arsenicin rice: Estimating normal levels of total arsenic in rice grain. Environ. Sci. Technol. 2008, 42, 3856-3860.
3. Sanz, E.; Munoz-Olivas, R.; Camara, C. A rapid and novel alternative to conventional sample treatment for arsenic speciation in rice using enzymatic ultrasonic probe. Anal Chim. Acta 2005, 535, 227-235.
4. Pizarro, I.; Gomez, M.; Palacios, M. A.; Camara, C. Evaluation of stability of arsenic species in rice. Anal Bioanal Chem. 2003, 376, 102-109.
5. 蔡佳穎. 液相層析結合感應耦合電漿質譜儀與環境樣品中鉻與硒及穀物樣品中砷與硒型態分析之應用. 國立中山大學, 高雄市, 2009
6. Qin J.; Li H.; Lin, C. Fenton process-afected transformation of roxarsone in paddy rice soils: Effects on plant growth and arsenic accu,ulation in rice grain. Ecotoxicology and Environmental Safety 2016, 130, 4-10.
7. 王孝銘. 液相層析結合化學蒸氣生成感應耦合電漿質譜儀於水樣中砷物種之分析. 國立中山大學, 高雄市, 2013.
8. Pohl, P. Recent advances in chemical vapor generation via reaction with sodium tetrahydroborate. TrAC, Trends anal Chem, 2004, 23, 21-27.
9. D’Ulivo, A. Cheical vapor generation by tetrahydroborate(III) and other borane complexes n aqueous media. Acritical discussion of fundamental processes and mechanisms involved in reagent decomposition and hydride formation. Spectrochim. Acta Part B 2004, 59, 793-825.
10. Silva, M. M. D.; Jesus, A. D.; Zmozinski, A. V.; Vieira, M. A.; Ribeiro, A. S. Determination of mercury in naphtha and petroleum condensate by photochemical vapor generation atomic absorption spectrometry. Microchem. J. 2013, 110, 227-232.
11. Lust, A. New dynamic reaction cell technology. Atomic Spectroscopy 1999, 20, 1-36.
12. 劉殷孝. 液相層析結合感應耦合電漿質譜儀與電噴灑質譜儀與水樣與食品中鉻與銻之分析應用. 國立中山大學, 高雄市, 2014
13. Schmeisser, E.; Goessler, W.; Kienzl N.; Francesconi, K. A. Volatile analytes formed from arsenosugars: Determiation by HPLC-HG-ICP-MS and implications for arsenic speciation analyses Anal. Chem. 2004, 76, 418-423.
14. Chen, H.; Brindle, I. D.; Le, X. C. Prereduction of arsenic(V) to arsnic(III), enhancement of the signal, and reduction of interferences by L-cysteine in the determination of arsenic by hydride generation. Anal. Chem. 1992, 64, 667-672.
15. Hwang, C. J.; Jiang. S J. Determination of arsenic compounds in water samples by liquid chromatography-inductively coupled plasma mass spectrometry with an in situ nebulizer-hydride generator. Anal. Chim. Acta 1994, 289, 205-213.
16. Sanchez-Rodas, D.; Gomez-Ariza, J. L.; Giraldez, I.; Velasco, A.; Morales, E. Arsenic speciation in riverand estuarine waters from southwest spain. Sci Total Environ. 2005, 345, 207-217.
17. Sanz, E.; Munoz-Olivas, R.; Camara, C. A Comparison of biota sample pretreatments for arsenic speciation with coupled HPLC-HG-ICP-MS. Analyst 2012, 125, 401-407
18. Tsai, M. W.; Sun, Y. C.On-line coupling of an ultraviolet titanium dioxide film reactor with a liquid chromatography/hydride generation/inductively coupled plasma mass spectrometry system for continuous determination of dynamic microdialysate samples. Rapid Commum Mass Spectrom. 2008, 22, 211-216.
19. Sur, R.; Dunemann, L. Method for the determination of five toxicologically relevant arsenic species in human urine by liquid chromatography-hydride generation atomic absorption spectrometry. J. Chromatogr. B 2004, 807, 169-176.
20. 鄭雅瑜 液相層析結合感應耦合電漿質譜儀與環境水樣與食米樣品中砷物種分析及酒品含鉻化合物之分析應用. 國立中山大學, 高雄市, 2015.
21. Li, X.; Xie, K.; Yue, B.; Gong, Y.; Shao, Y.; Shang, X.; Wu, Y. Inorganic sarsemic contamination of rice from Chinese major rice-producing areas and exposure assessment in Chinese population. Science China-Chemistry 2015, 407, 100-107.
22. Zhu, Y. G.; Sun, G. X.; Lei, M.; Teng, M.; Liu, Y. X.; Chen, N. C.; Wang. L. H.; Carey, A. M.; Deacon, C.; Raab A.; Meharg, A. A.; Williams, P. N. High percentage inorganic arsenic content of mining impacted and nonimapcted Chinese rice. Environ Sci Technol. 2008, 42, 5008-5013.
23. Batista, B. L.; Barbosa, F. Speciation of arsenic in rice and estimation of daily intake of different arsenic species by Brazilians through rice consumption. J Hazard Mater 2011, 191, 342-348.
24. D’Amato M,; Forte, G.; Caroli, S. Identification and quantification of major species of arsenic in rice. J AOAC Int. 2004, 87, 238-243.
25. Sanz, E.; Munoz-Olivas, R.; Camara, C.; Sengupta, M. K.; Ahamed, S. Arsenic speciation in rice, straw, soil, hair and nails samples from the arsnic-affected areas of middle and lower Ganga plain. J Environ Sci Health 2007, 42, 1695-1705.