Recently, the levels of heavy metals in medicinal plants have aroused widespread concern because these

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:

• 1 Introduction and elemental Pb from the soil to underground water goes
• attention. Approximately 19.4% of arable land (2.6
  107 hm2) though the Pb content in the higher parts of plants (such as
• in China suffers from heavy metal pollution.1 According to fruits, seeds, and leaves) is low, it remains toxic when consumed
• a 2014 National Soil Pollution Survey Bulletin reported by the by humans due to the large accumulation of Pb in the roots.5
• Ministry of Environmental Protection of China, in 7% of cases, In the last quarter of the last century, people became more
• parts.2 A well-documented phenomenon is Itai-Itai disease, approximately 4 billion people for certain aspects of primary
• which arises due to the accumulation of Cd residue in rice.3 A health care. However, the existence of heavy metals may have
• exist in many fertilizers is Pb, which is easily absorbed and products prepared from medicinal plants.6 Incidents of exces-
• harm to human lives and health. According to Rodriguez et al.,4 and causing signicant economic losses to the TCM industry.7
• School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China
• 43882 | RSC Adv., 2020, 10, 43882–43893 This journal is © The Royal Society of Chemistry 2020
• phytoremediation of heavy metals is of great signicance8–10 and and poses no ecological risk, and the selected crops can be directly
• pollution due to its low cost, which can be 1000 times lower than use low-accumulating plants to remediate polluted soil.
• ing.11 A desired phytoremediation model would not only be mechanisms of low- and non-low-accumulating plants under
• good economic benet.12 However, few plants are both hyper- mechanisms of repair of low-accumulating plants and non-low-
• even though they have lower uptake capacities than hyper- 2.1 The cultivation of medicinal plants
• accumulators. Zhi et al.13 found that Chinese soybean (Tiefeng 29) Soil samples were obtained from depths of 0–20 cm from the
• was a low Pb-accumulator. Research by Manan et al.14 showed that surface, passed through a 4 mm sieve, and then mixed with
• C. asiatica is a low-accumulator of Zn and Pb. Research by Huang suitable amounts of CdCl2$2.5H2O or Pb(NO3)2 solution. Plastic
• et al.15 indicated that Chinese cabbage (No. 12, No. 21) and owerpots (20 cm diameter
  15 cm depth) were used, con-
• cabbage (No. 6, No. 7) are low Cd-accumulating vegetables. taining 2.5 kg of soil in each case. Five treatments were adopted:
• The “rhizosphere” is generally dened as an area of soil 1 CK treatment (control, no Cd or Pb); 2 Cd treatments, i.e., T1
• around the roots where microbes are highly active and affected by (1.0 mg Cd kg1 soil) and T2 (2.5 mg Cd kg1 soil); and 2 Pb
• the secretion of a microbial community by the roots.16 Root treatments, i.e., T1 (500 mg Pb kg1 soil) and T2 (1500 mg Pb
• exudates usually include amino acids, sugars, organic acids, high kg1 soil). T1 and T2 indicate low and medium contamination
• molecular weight compounds, and phenolic compounds.17,18 Low levels. The heavy metal pollution classication standard and
• phenols) and high molecular weight compound (polysaccharides heavy-metal pollution levels.27,28 500 g of each soil sample was
• and proteins) root exudates play critical roles in rhizospheric accurately weighed and placed in a 300-mesh Nylon rhizosphere
• processes.19 In addition, the root exudates of wheat and rice also bag with a diameter of 15 cm. A rhizosphere bag was placed in
• plants that were not treated with Pb and/or Cd.20 Salt et al.21 found sphere soil.29 The soil was watered and the pots were then kept
• distribution and absorption of Pb and Cd in plants.22 leaf Schizonepeta Herb (Nepeta cataria L.) seeds used in this
• membranes under heavy-metal stress, leading to increased with 2% (v/v) hydrogen peroxide for 10 minutes, the seeds were
• plants under these stresses, plants have to modulate the 2.2 Determination of heavy metals in soil and plant samples
• and deionized water 3 times, and they were then divided into
• containing 13% concentrated HClO4 and 87% concentrated
• CAT and POD is to remove H2O2 in organisms.25
• HNO3.30 ICP-AES (Spectro Arcos, Germany) was used to deter-
• mine the Cd and Pb levels.29 The recoveries of these two
• matrix, the element concentration in such plant tissue is still very Approximately 2 g of rhizosphere soil was weighed and placed
• low.26 The cultivation process of low-accumulating plants is simple in a 10 ml centrifuge tube. To inhibit microbial activity, 4 ml of
• This journal is © The Royal Society of Chemistry 2020 RSC Adv., 2020, 10, 43882–43893 | 43883
• 0.1% H3PO4 solution was added to the root exudate compo-

Methods (brief)

• accumulators. Zhi et al.13 found that Chinese soybean (Tiefeng 29) Soil samples were obtained from depths of 0–20 cm from the
• phenols) and high molecular weight compound (polysaccharides heavy-metal pollution levels.27,28 500 g of each soil sample was
• plants under these stresses, plants have to modulate the 2.2 Determination of heavy metals in soil and plant samples
• samples were completely dried in an oven at 70  C, and then
• weighed and ground into powder. 0.50 g of soil sample and
• 0.50 g of plant sample were digested (v/v) in 12 ml of solution
• HNO3.30 ICP-AES (Spectro Arcos, Germany) was used to deter-
• centrifuged with a syringe lter (0.45 mm). 0.25 g of soil sample
• All treatments were repeated three times and each sample was catnip, thyme, and Fineleaf Schizonepeta Herb.
• metal accumulation. The heavy metal levels in the shoots and concentration in the corresponding soil sample; and
• Jialun Lv collected data; Yajun Li and Zehua Wu had primary

Implications

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Wiki pages this source may touch

• Fish — marine, non-predatory (sardines, anchovies, salmon, cod)
• Cadmium
• Lead
• Nickel
• Aluminum
• Chromium

Verification notes

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Update history

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