Jurkovic et al. 2025 — Heavy metals in flooded-area chard

Jurkovic et al. measured heavy metals and microbiological indicators in a soil-plant system after major flooding in central Bosnia and Herzegovina. The source is routeable to leafy vegetables because it reports chard tissue measurements, but it should remain jurisdiction- and event-specific because the sampling frame is a flooded-area case study. The paper found elevated Pb in soils and sludge, root-favoring Pb behavior in chard, and cases where chard Cd exceeded permissible amounts.

Key numbers

The study measured Cu, Zn, Ni, Co, Pb, Cd, Fe, Cr, and Mn by flame atomic absorption spectroscopy. Soil and sludge samples were extracted with aqua regia for pseudo-total metals and EDTA for available metals. Chard samples were divided into roots, stems, and leaves.

In pseudo-total soil/sludge results, flooded-area Pb ranged from 98.8 to 277.6 mg/kg, with an average of 180.5 mg/kg. Control-area Pb ranged from 41.9 to 321.1 mg/kg, with an average of 118.7 mg/kg. Sludge Pb ranged from 97.7 to 242.5 mg/kg, with an average of 159.6 mg/kg.

Pseudo-total Cd was much lower than Pb: flooded-area Cd ranged from 0.1 to 0.5 mg/kg, with an average of 0.2 mg/kg; control-area Cd ranged from 0.1 to 0.5 mg/kg, with an average of 0.2 mg/kg; sludge Cd was 0.1 mg/kg for maximum, minimum, and average. The authors state that average Pb in investigated soils exceeded the 80 mg/kg maximum permissible amount they cite, while Cd, Cr, and Co were below cited maximum permissible values.

The authors report that EDTA-extractable heavy metals followed the sequence Pb > Mn > Fe > Cu > Zn > Ni > Co > Cr > Cd. They estimate average Pb extractability at 18.7% and Cu extractability at 46.53%, while Cd was not detectable by AAS in the EDTA extraction.

For chard tissue, Figures 7 through 9 show plant concentrations in mg/kg. Figure 9 compares available soil metal against average plant tissues and shows approximate average Pb near 38 mg/kg in leaves, 46 mg/kg in stems, and 41 mg/kg in roots. Figure 9 shows approximate average Cd near 0 mg/kg in leaves, 0 mg/kg in stems, and about 0.2 mg/kg in roots; the text states that Cd varied among chard tissues and that some chard cases had Cd above permissible amounts. The figure-derived plant values should be treated as approximate until a table-level extraction is available.

Methods (brief)

The study sampled soil, sludge, and chard from flooded and non-flooded control areas after autumn 2024 flooding. Soil and sludge were characterized for basic quality parameters, pseudo-total metals by aqua regia extraction, available metals by EDTA extraction, microbial counts, and carbon/nitrogen content. Chard roots, stems, and leaves were dried and analyzed for the same nine metals by FAAS.

Implications

Certification: This is direct occurrence evidence for chard/leafy-vegetable supply-chain matrices, but it is not a clean-market benchmark source. The values reflect a flood-impacted setting in Bosnia and Herzegovina and should be stratified as event- and jurisdiction-specific context.

Courses: The source is useful for explaining why flooding can change heavy-metal mobility and why edible tissue may not track total soil metals one-to-one.

App: The source supports a leafy-vegetable evidence note for Pb and Cd under flood/disaster contamination conditions.

Microbiome: The paper includes soil microbial measurements but does not assess human or product microbiome outcomes.

Wiki pages this source may touch

• leafy-vegetables-other
• non-root-vegetables
• leafy-greens
• leafy-vegetables
• lead
• cadmium
• nickel
• chromium

Verification notes

The PDF metadata and article first page identify ACS Omega 2025, DOI 10.1021/acsomega.5c08533. The automated filename suggested a leave-on preparation query, but the actual source is a chard soil-plant study. Product-tissue values are presented in figures rather than a text table; this page marks figure-read plant averages as approximate and relies on exact text-extracted soil/sludge table values where available.

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.