Arsenic Uptake, Toxicity, Detoxification, and

Overview

This source page is a mechanical bulk-ingest record for a PDF in the methylmercury infant-formula research pull. 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:

• Ghulam Abbas 1 , Behzad Murtaza 1 , Irshad Bibi 2,3 , Muhammad Shahid 1, *,
• Nabeel Khan Niazi 2,3,4, * ID , Muhammad Imran Khan 2 , Muhammad Amjad 1 ,
• Munawar Hussain 2 and Natasha 1
• 1 Department of Environmental Sciences, COMSATS Institute of Information Technology,
• drmuhammadamjad@ciitvehari.edu.pk (M.A.); natasha564ag@gmail.com (N.)
• 2 Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad,
• Faisalabad 38040, Pakistan; irshad.niazi81@gmail.com (I.B.); khanimran1173@yahoo.com (M.I.K.);
• 3 MARUM and Department of Geosciences, University of Bremen, D-28359 Bremen, Germany
• 4 Southern Cross GeoScience, Southern Cross University, Lismore 2480, Australia
• nabeel.niazi@uaf.edu.pk (N.K.N.); Tel.: +92-300-669-1981 (M.S.); +92-41-920-1089 (N.K.N.)
• environmental issue (1,2). Most of the PTEs are toxic to plants and animals including humans (3–5).
• Int. J. Environ. Res. Public Health 2018, 15, 59; doi:10.3390/ijerph15010059 www.mdpi.com/journal/ijerph
• Int. J. Environ. Res. Public Health 2018, 15, 59 2 of 45
• Among the PTEs, arsenic (As) is considered as one of the most highly toxic and carcinogenic (6–9).
• (IARC) have ranked As and its compounds as a Group 1 human carcinogen (10,11). The Agency
• for Toxic Substances and Disease Registry (ATSDR) has ranked As at the top among the 20 priority
• hazardous substances (12). It has been reported that one out of every 60 people on this planet is living
• in a region where the concentration of As in groundwater is 50 µg L−1 or greater (2,13).
• and pesticides in agriculture, and irrigation with As-contaminated groundwater (2,6,14).
• The abundance of As is evident due to its presence in more than 200 minerals in the Earth’s
• crust, of which 60% are in arsenate form, 20% are sulfides and sulfo-salts, and the remaining 20%
• are in the form of arsenites, arsenides, silicates, oxides, and elemental As (15). In the soil and water
• environments, As can exist in four different oxidation states: As(-III), As(0), As(III), or As(V) (16).
• reduced conditions, and As(V) is dominant under oxidized environments (2).
• as such could control plant uptake of As and its biogeochemical behavior in the soil-plant system (17,18).
• nature (19). It has been stated that the inorganic form of As is more lethal compared to its organic
• form (20). Further, amongst its inorganic forms, As(III) is more soluble and 60 times more toxic and
• enzymes, culminating inhibition in cellular function and eventually cell death (21–26). However, some
• Duncan et al. (27) reported that dimethylarsenate (DMA), compared to As(V), was more toxic to wheat.
• They reported that the germination rates of wheat exceeded 80% under As(V) stress but decreased
• significantly to 20–40% under DMA stress. Similarly, DMA decreased grain yields by 20–50% compared
• Arsenic is considered non-essential for plants and other organisms (2). Arsenic uptake by plant
• thought to be dependent upon exchangeable (bioavailable) As concentration in soil (17,18,28). In plants,
• As mainly enters as an inorganic form, As(III) or As(V) (29) via transporter proteins that is likely
• information about specific transporters for As uptake by plants is lacking (30). Being analog to each
• physiological, biochemical, and molecular alternations (see Figure 1) (6,26,32–34). The most dangerous
• such as superoxide radical (O2− ), hydroxyl radical (OH), and hydrogen peroxide (H2 O2 ) (17,18,35,36).
• macromolecules, including lipids, proteins, carbohydrate, and DNA (6,37–42). It has been noticed that
• the generation of the ROS in plants is linked to the conversion of As(V) to As(III) (22,37,43).
• increasing activities of the antioxidant enzymes (26,36,40,41,44). The enzymes involved in the
• Int. J. Environ. Res. Public Health 2018, 15, 59 3 of 45
• (GR), and ascorbate peroxidase (APX) (34,41,44–46). Among non-enzyme antioxidants, proline is a

Methods (brief)

• Duncan et al. (27) reported that dimethylarsenate (DMA), compared to As(V), was more toxic to wheat.
• significantly to 20–40% under DMA stress. Similarly, DMA decreased grain yields by 20–50% compared
• dimethylarsenite (DMA(III)), dimethylarsinate (DMA(V)), arsenocholine, arsenosugars, arsenobetaine,
• hydroponic experiment using 46 maize species and reported that the transport of DMA(V) from root
• have been reported to accumulate up to 89% of DMA (145).
• such as DMA can strongly bind to sulfur-activated GSH (144). It has been well documented that
• 27. Duncan, E.G.; Maher, W.A.; Foster, S.D.; Krikowa, F.; O’Sullivan, C.A.; Roper, M.M. Dimethylarsenate (DMA)
• 133. Liu, W.-J.; Wood, B.A.; Raab, A.; McGrath, S.P.; Zhao, F.-J.; Feldmann, J. Complexation of arsenite with
• 134. Raab, A.; Feldmann, J.; Meharg, A.A. The nature of arsenic-phytochelatin complexes in Holcus lanatus and
• 140. Ye, W.-L.; Wood, B.A.; Stroud, J.L.; Andralojc, P.J.; Raab, A.; McGrath, S.P.; Feldmann, J.; Zhao, F.-J. Arsenic
• 141. Li, R.-Y.; Ago, Y.; Liu, W.-J.; Mitani, N.; Feldmann, J.; McGrath, S.P.; Ma, J.F.; Zhao, F.-J. The rice aquaporin
• 142. Raab, A.; Schat, H.; Meharg, A.A.; Feldmann, J. Uptake, translocation and transformation of arsenate and
• 144. Raab, A.; Wright, S.H.; Jaspars, M.; Meharg, A.A.; Feldmann, J. Pentavalent arsenic can bind to biomolecules.
• 311. Karimi, N.; Ghaderian, S.M.; Raab, A.; Feldmann, J.; Meharg, A.A. An arsenic-accumulating, hypertolerant
• 334. Zhang, X.; Uroic, M.K.; Xie, W.-Y.; Zhu, Y.-G.; Chen, B.-D.; McGrath, S.P.; Feldmann, J.; Zhao, F.-J.

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

• Fish — marine, non-predatory (sardines, anchovies, salmon, cod)
• Seaweed/kelp foods (nori, wakame, kombu, dulse — as food products)
• Mercury
• Cadmium
• Lead
• Arsenic
• Nickel
• Aluminum
• Chromium

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.