Toxicology Reports 11 (2023) 295–306

Overview

This source page is a mechanical bulk-ingest record for a PDF in the research-pulls corpus. It preserves source-level identity, routeable product/analyte scope, and exact extracted numeric lines for later human or fresh-context audit. It does not derive HMTc thresholds, percentiles, or brand-by-brand comparisons.

Key numbers

The worker extracted the full PDF text with layout preservation twice and compared extraction hashes before commit. The following lines are copied from numeric/table-bearing regions of the PDF and retain the source units and wording where legible:

• population(IARC) (1–4). Long-term exposure to As can induce oxidative (8,9,13–15). Given that rice is a staple food for over 60% of the global
• physiological state of the rice plant (26,31–34). The mean As (also known as NIP2;1), play a crucial role in facilitating arsenite uptake
• factor (TF) of 0.05–3.8 (mean: 0.76) from soil to shoots of rice and a 2.5. Arsenic speciation and methylation in rice
• lower TF from soil to grain of 0.01–0.12 (mean: 0.04) demonstrating
• that larger proportion of As is sequestered and stored in the vacuoles In rice grains, methylated arsenic species account for 10–90% of the
• to As-contaminated soil reduced As uptake in rice plants by up to 56% hury et al. (74,75) observed that rice cultivated in Bangladesh, where
• by up to 42% and 36%, respectively (60). These findings suggest that contaminated areas. Similarly, several studies have reported that rice
• methylated As species (65,67). periments in Aberdeen, Scotland (16). The study reported a 27% lower
• to remove impurities and is reused for non-potable purposes, such as and methylation of As in rice plants (9,97,103). The researchers found
• mulation in rice grains by 18.2–52.7% (84,85). The authors recom­ DMA in the rice grain, suggesting that AWD can enhance the methyl­
• Table 2 promotes the methylation of As in soil and water systems (101). During
• methylation of iAs to DMA and inhibits the methylation of MMA. The mechanisms (84,107) (Table 2). Firstly, SDI reduces the amount of
• promote the activity of As-methylating microorganisms in the soil, for uptake by the rice plant (Table 2). Besides, reducing available As in
• reported lower MMA (0.003 ± 0.004 mg kg− 1) (Table 1) in rice bran activity of microorganisms that convert iAs to organic methylated As
• For instance, Weber et al. (13) also reported a much lower mean DMA For example, a study conducted in China found that SDI reduced the tAs
• (0.031 ± 0.010 mg kg− 1) in rice bran under AWD compared to that content in the rice grain by 39% compared to continuous flooding
• under CF (0.149 ± 0.0622 mg kg− 1) (Table 1). In contrast, under CF, the (Table 2). Another study conducted in California, USA, showed that SDI
• anaerobic conditions in the soil promote the methylation of iAs to MMA. reduced the total As content in the rice grain by 24% compared to flood
• rice grain was higher in plants grown under CF compared to AWD which thylarsinic acid (DMA), in the rice grain (Table 2). A study conducted in
• reduced As accumulation and enhanced methylation of As in rice plants grain by 68% compared to flood irrigation. Thus, SDI can significantly
• under ARC compared to that under CF (Table 2). The authors associated It is reported that the mechanisms of As-methylation in rice are
• In specific pH ranges, like slightly acidic to neutral soils, there’s a in six steps namely: 1) uptake of As, 2) transport of inorganic As, 3)
• tial) favour the stability of AsV (99,101). This means that in oxidized dissolution into the solution and subsequent interaction with proximate
• es070627i. heavy metals in leaf vegetables from agricultural soils and associated potential
• biological solutions to reduce arsenic risk from rice (|), Front. Plant Sci. 8 (2017) C. Basu, C.R. Chanda, D. Lodh, K.C. Saha, S.K. Mukherjee, et al., Groundwater
• (60) Y. Liang, M. Nikolic, R. Bélanger, H. Gong, A. Song (first.), in: Y. Liang, safe for vegetable irrigation? Empirical evidence from Lebanon, Water 14 (2022),
• Total Environ. 650 (2019) 546–556, https://doi.org/10.1016/j. genotype on lead concentration in rootstalk vegetables and the selection of

Methods (brief)

• nificant health risk to humans when consumed through contaminated methylarsonous acid (MMA(III)), dimethylarsinous acid (DMA(III)),
• food, such as rice, being a staple food for a large portion of the world’s monomethylarsonic acid (MMA(V)) and dimethylarsinic acid (DMA(V))
• inorganic arsenate (AsV). In recent years, there has been a growing in­ global issue, with varying levels of iAs detected in rice samples world­
• such as phosphate transporters and high-affinity phosphate transporters MMA and DMA, originate from biological processes involving microbial
• located in the roots. total arsenic, mainly present as DMA, partly as MMA and TMAO (67,68)
• that P that is a chemical analogue of As and both are up-taken through more easily excreted forms such as MMA and DMA (69–71).
• soil amendment with Si can be an effective strategy for mitigating As samples from As-affected areas of West Bengal, India, had higher total As
• compared to rice samples from non-affected areas (76,77).
• rice crops (82,83). For instance, a study investigating the impact of increased the proportion of dimethylarsinic acid (DMA), which is a less
• mulation in rice grains by 18.2–52.7% (84,85). The authors recom­ DMA in the rice grain, suggesting that AWD can enhance the methyl­
• with appropriate water management practices and organic amendments grown under AWD has higher levels of DMA and lower levels of MMA
• AsV + 3e- + 3 H+ → AsIII (DMA), less toxic form of As, in the rice grain compared to CF suggesting
• Methylation of MMA to DMA as lower (>7 folds), respectively, in plants cultivated under CF compared
• MMA + SAM → DMA + SAH accumulation and the methylation of As are stimulated and inhibited,
• bacteria oxidize AsIII to AsV. DMA and lower levels of MMA compared to rice grown under CF, sug­
• Under anoxic conditions, other gesting that aerobic conditions promote the methylation of iAs to DMA
• DMA. ylate iAs to DMA over MMA (41,89,106). In contrast, under CF, the
• methylation of iAs to DMA and inhibits the methylation of MMA. The mechanisms (84,107) (Table 2). Firstly, SDI reduces the amount of

Implications

This page makes the source discoverable for category-level evidence routing. Values remain source-native and should be used only with the stated matrix, species, basis, geography, and censoring context from the paper. The page does not convert total mercury to methylmercury or use total arsenic as inorganic arsenic.

Wiki pages this source may touch

• baby-cereals-dry
• Fish — marine, non-predatory (sardines, anchovies, salmon, cod)
• Mercury
• Cadmium
• Lead
• Arsenic

Verification notes

• Identity check: DOI, raw handle, candidate cite-key, and SHA-256 were compared against existing wiki/sources/ pages before creation.
• Full-PDF read: pdftotext -layout was run on the full PDF twice; extracted text hashes matched before the page was written.
• Numeric verification: numeric/table-bearing lines were selected mechanically from the verified extraction and preserved without unit conversion or rounding.
• Brand firewall: the worker skips PDFs when extracted numeric lines appear brand/manufacturer-sensitive; this page contains category-level or species-level evidence only.
• HMTc firewall: no threshold, percentile, pass/fail, clean/dirty, or certification math is stated.

Update history

The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and 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.