1.An approach for identification and determination of arsenic species in the extract of kelp.
Yu LL1, Wei C, Zeisler R, Tong J, Oflaz R, Bao H, Wang J. Anal Bioanal Chem. 2015 May;407(12):3517-24. doi: 10.1007/s00216-015-8567-8. Epub 2015 Mar 3.
The National Institute of Standards and Technology is developing a kelp powder standard reference material (SRM) in support of dietary supplement measurements. Edible seaweeds such as kelp and laver consumed as diet or dietary supplement contain tens of mg/kg arsenic. The speciation information of arsenic in the seaweed should be provided because the total arsenic alone does not fully address the safety issue of the dietary supplement as the value assignment is originally intended. The inability to avail all arsenic species for value assignment measurements prevented the certification of arsenic species in the candidate SRM; however, approximately 70 % of total arsenic extracted with a 1:1 volume fraction of methanol:water mixture allowed arsenic speciation values to be assigned to a procedure-defined extract, which may be used for method validation in research to improve upon current extraction and measurement practices. Arsenic species in kelp and laver were identified using electrospray ionization ion trap time of flight mass spectrometry (ESI-IT-TOF).
2.IgE antibodies and urinary trimethylarsine oxide accounted for 1-7% population attributable risks for eczema in adults: USA NHANES 2005-2006.
Shiue I1,2. Environ Sci Pollut Res Int. 2015 Dec;22(23):18404-9. doi: 10.1007/s11356-015-5084-4. Epub 2015 Aug 2.
Population attributable risks from serum IgE and dust miteallergen concentrations and environmental chemicals for eczema are unclear. Therefore, it was aimed to examine serum IgE and allergen concentrations and environmental chemicals for eczema in adults and to calculate population attributable risks in a national and population-based setting. Data retrieved from the National Health and Nutrition Examination Survey, 2005-2006, was analyzed. Information on demographics and self-reported ever eczema was obtained by household interview. Bloods and urines (sub-sample) were also collected during the interview. Adults aged 20-85 were included. Statistical analyses were using chi-square test, t test, survey-weighted logistic regression modeling, and population attributable risk (PAR) estimation. Of all the included American adults (n = 4979), 310 (6.2%) reported ever eczema. Moreover, more eczema cases were observed in female adults but fewer cases in people born in Mexico.
3.Establishment of a method for determination of arsenic species in seafood by LC-ICP-MS.
Zmozinski AV1, Llorente-Mirandes T2, López-Sánchez JF3, da Silva MM1. Food Chem. 2015 Apr 15;173:1073-82. doi: 10.1016/j.foodchem.2014.10.102. Epub 2014 Oct 28.
An analytical method for determination of arsenic species (inorganic arsenic (iAs), methylarsonic acid (MA), dimethylarsinic acid (DMA), arsenobetaine (AB), trimethylarsine oxide (TMAO) and arsenocholine (AC)) in Brazilian and Spanish seafood samples is reported. This study was focused on extraction and quantification of inorganic arsenic (iAs), the most toxic form. Arsenic speciation was carried out via LC with both anionic and cationic exchange with ICP-MS detection (LC-ICP-MS). The detection limits (LODs), quantification limits (LOQs), precision and accuracy for arsenic species were established. The proposed method was evaluated using eight reference materials (RMs). Arsenobetaine was the main species found in all samples. The total and iAs concentration in 22 seafood samples and RMs ranged between 0.27-35.2 and 0.02-0.71 mg As kg(-1), respectively. Recoveries ranging from 100% to 106% for iAs, based on spikes, were achieved. The proposed method provides reliable iAs data for future risk assessment analysis.
4.Reversed Phase Column HPLC-ICP-MS Conditions for Arsenic Speciation Analysis of Rice Flour.
Narukawa T1, Matsumoto E, Nishimura T, Hioki A. Anal Sci. 2015;31(6):521-7. doi: 10.2116/analsci.31.521.
New measurement conditions for arsenic speciation analysis of rice flour were developed using HPLC-ICP-MS equipped with a reversed phase ODS column. Eight arsenic species, namely, arsenite [As(III)], arsenate [As(V)], monomethylarsonic acid (MMAA), dimethylarsinic acid (DMAA), trimethylarsine oxide (TMAO), tetramethylarsonium (TeMA), arsenobetaine (AsB) and arsenocholine (AsC), were separated and determined under the proposed conditions. In particular, As(III) and MMAA and DMAA and AsB were completely separated using a newly proposed eluent containing ammonium dihydrogen phosphate. Importantly, the sensitivity changes, in particular those of As(V) and As(III) caused by coexisting elements and by complex matrix composition, which had been problematical in previously reported methods, were eliminated. The new eluent can be applied to C8, C18 and C30 ODS columns with the same effectiveness and with excellent repeatability. The proposed analytical method was successfully applied to extracts of rice flour certified reference materials.