Rahman 2007 - total arsenic distribution across Bangladesh rice grain fractions

Rahman and colleagues measured total arsenic in rice plants and milled rice fractions from two Bangladesh rice varieties grown in arsenic-affected Satkhira district fields. The paper reports dry-weight total arsenic values for raw rice, brown rice, bran-polish, polish rice, husk, straw, root, soil, and irrigation water. For HMI routing, the edible rice-grain values are the product occurrence data; soil, water, straw, root, husk, and bran-polish values are supply-chain context rather than direct rice-bulk-grain occurrence rows.

Key numbers

• Publication identity: Chemosphere 69(6):942-948, DOI 10.1016/j.chemosphere.2007.05.044; the raw PDF is an author manuscript with a first-page title matching the published article.
• Study area context: irrigation water from shallow tube wells contained total arsenic 0.070±0.006 mg l-1 in the abstract (n=6), while the Results paragraph reports study-area soil and water total arsenic of 14.5±0.1 mg kg-1 and 0.070±0.006 mg l-1, respectively (n=3).
• Rice varieties: BRRI dhan28 and BRRI hybrid dhan1; rice, soil, and water were collected from arsenic-affected Itagasa and Guddirdangi village sampling areas in Satkhira district, Bangladesh.
• Raw rice total arsenic: BRRI dhan28 0.6±0.0 mg kg-1 dry weight; BRRI hybrid dhan1 0.7±0.2 mg kg-1 dry weight; the paper states n=3.
• Brown rice total arsenic: BRRI dhan28 non-parboiled 0.8±0.1 mg kg-1 dry weight and parboiled 0.5±0.0 mg kg-1 dry weight; BRRI hybrid dhan1 non-parboiled 0.8±0.2 mg kg-1 dry weight and parboiled 0.6±0.2 mg kg-1 dry weight.
• Polish rice total arsenic: BRRI dhan28 non-parboiled 0.4±0.0 mg kg-1 dry weight and parboiled 0.3±0.1 mg kg-1 dry weight; BRRI hybrid dhan1 non-parboiled 0.4±0.1 mg kg-1 dry weight and parboiled 0.5±0.1 mg kg-1 dry weight.
• Rice-fraction context: husk total arsenic was 1.1±0.2 and 0.7±0.1 mg kg-1 dry weight for non-parboiled and parboiled BRRI dhan28; the corresponding BRRI hybrid dhan1 values were 1.6±0.1 and 0.8±0.2 mg kg-1 dry weight.
• Bran-polish context: BRRI dhan28 bran-polish total arsenic was 0.9±0.1 and 0.6±0.2 mg of As kg-1 dry weight for non-parboiled and parboiled rice. The extracted text does not print the corresponding BRRI hybrid dhan1 bran-polish numeric cells, although the paper states the hybrid fractions contained higher arsenic than BRRI dhan28 fractions.
• Plant-tissue context: BRRI dhan28 contained 46.3±1.4 in root, 1.7±0.1 in straw, and 0.6±0.0 mg kg-1 dry weight in raw rice; BRRI hybrid dhan1 contained 51.9±1.3, 1.9±0.1, and 0.7±0.2 mg kg-1 dry weight, respectively.
• Fraction mass distribution: in Table 1, brown rice represented 77.1, 75.9, 77.9, and 77.8% dry weight for BRRI dhan28 non-parboiled, BRRI dhan28 parboiled, BRRI hybrid dhan1 non-parboiled, and BRRI hybrid dhan1 parboiled rice, respectively; polish rice represented 69.8, 68.6, 67.0, and 67.2% dry weight.
• The source’s own ordering statement for rice fractions is rice hull > bran-polish > brown rice > raw rice > polish rice. This is preserved as the authors’ total-arsenic distribution finding, not converted into inorganic arsenic.

Methods (brief)

Rice and soil samples were acid-digested using nitric acid and perchloric acid; soil digestion also used sulfuric acid. Water samples from shallow tube wells were filtered through 0.45 Millipore filter paper and preserved with 2M hydrochloric acid. Total arsenic was determined by hydride generation atomic absorption spectrophotometer (HG-AAS) using a Perkin-Elmer AAnalyst 100 with FIAS 100. Quality checks included reagent blanks, spikes, duplicate samples, spike recovery 87.4% (n = 6), and NIST SRM 1573a tomato leaf with certified arsenic 0.112±0.004 µg g-1 and measured arsenic 0.120±0.009 µg g-1. The method measured total arsenic only; no inorganic-arsenic speciation was performed.

Implications

Certification (HMTc): This source contributes Bangladesh field-rice total-arsenic occurrence context for the rice-bulk-grain row, especially dry-weight brown-rice and polish-rice fraction values. It is not a direct inorganic-arsenic source and should not be pooled as iAs.

Courses: The paper is a useful supply-chain case study for how irrigation-water arsenic and milling/parboiling steps affect the distribution of total arsenic across root, straw, husk, bran-polish, brown rice, and polish rice.

App: The source adds a rice ingredient contamination-profile example for tAs on a dry-weight basis, with prominent labels that the paper reports total arsenic rather than inorganic arsenic.

Wiki pages this source may touch

• arsenic-total
• rice
• rice-bulk-grain

Verification notes

• PDF text was extracted with pdftotext -layout to /tmp/ingest.txt. The extracted text was checked against the rendered PDF pages because Table 1 extracted cleanly but some later table bodies were not present in the text layer.
• Identity checks before creation: DOI 10.1016/j.chemosphere.2007.05.044, exact title phrase, raw handle MFK_07-remediation-method, raw SHA-256 7fede1d0286d9029caf4deae1e0941e2719a4504a803ef9f839596725e646c0c, and cite key rahman2007-rice-grain-arsenic-fractions were searched in wiki/sources/ and evidence files. No existing source page was found; only intake/tracker metadata and unrelated log references appeared.
• DOI disambiguation: the manuscript reference list cites a related Rahman et al. Ecotoxicology and Environmental Safety article with DOI 10.1016/j.ecoenv.2007.01.005; that is not the identity DOI for this raw PDF. The title of this PDF resolves to Chemosphere DOI 10.1016/j.chemosphere.2007.05.044.
• Units and basis are preserved as printed: rice and plant-tissue values use mg kg-1 dry weight or mg of As kg-1 dry weight; water uses mg l-1; tomato-leaf CRM values use µg g-1.
• Speciation: the method is HG-AAS total arsenic after digestion. The page uses tAs and does not substitute inorganic arsenic (iAs).
• Scope separation: edible raw rice, brown rice, and polish rice values are product occurrence evidence; soil, irrigation water, root, straw, husk, and bran-polish are recorded as supply-chain or processing context.
• Missing table extraction: the source states that Table 4 contains the grain-fraction values. The extracted text provides the edible-rice and husk/BRRI dhan28 bran-polish values in the Results prose, but the BRRI hybrid dhan1 bran-polish numeric cells did not extract cleanly; those cells are therefore not reconstructed.
• Closed-vocabulary check: ingredients/rice, products/rice-bulk-grain, matrices: [rice-grain], jurisdictions: [BD], and metals: [tAs] match the current taxonomy/metals vocabulary. No rice-fraction-specific product slug was invented.

Page history

The five most recent substantive edits to this page. The full version history lives in git; when DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.