Rokanuzzaman et al. 2022 - Bangladesh egg metals

Rokanuzzaman and colleagues measured lead, cadmium, total chromium, copper, iron, and zinc in egg contents and eggshells from five poultry egg types collected around Jahangirnagar University in Savar, Bangladesh. The study includes indigenous chicken, white layer chicken, brown layer chicken, duck, and quail eggs. Values are reported in mg/kg; the source does not specify a wet- or dry-weight basis beyond drying the egg contents and eggshells before digestion.

Key numbers

• Sample frame: 10 samples total, described as five egg-content samples and five eggshell samples from indigenous chicken, white layer chicken, brown layer chicken, duck, and quail eggs.
• Egg contents, Table 1 (mg/kg): brown layer chicken egg Pb 0.044±0.002, Cd BDL, Cr 0.00208±0.0007, Cu BDL, Fe 8.9±0.9, Zn 21.38±1.6.
• Egg contents, Table 1 (mg/kg): indigenous chicken egg Pb 0.0421±0.07, Cd BDL, Cr 0.001±0.0005, Cu BDL, Fe 11.8±1.05, Zn 22.1±1.5.
• Egg contents, Table 1 (mg/kg): duck egg Pb 0.022±0.005, Cd BDL, Cr 0.00168±0.0004, Cu BDL, Fe 23.822±1.1, Zn 30.84±0.2.
• Egg contents, Table 1 (mg/kg): quail egg Pb 0.486±0.09, Cd 0.024±0.00325, Cr 0.002475±0.0006, Cu BDL, Fe 18.549±1.08, Zn 33.14±0.3.
• Egg contents, Table 1 (mg/kg): white layer chicken egg Pb 0.0001±0.00001, Cd 0.0131±0.00106, Cr 0.00194±0.0004, Cu 0.018±0.0035, Fe 18.486±1.07, Zn 35.36±0.4.
• Eggshells, Table 2 (mg/kg): brown layer chicken eggshell Pb 0.4609±0.064, Cd BDL, Cr BDL, Cu 0.029±0.007, Fe 0.41±0.061, Zn 0.04595±0.006.
• Eggshells, Table 2 (mg/kg): indigenous chicken eggshell Pb 0.3496±0.0283, Cd BDL, Cr BDL, Cu 0.0375±0.003, Fe 0.4195±0.072, Zn 0.0635±0.003.
• Eggshells, Table 2 (mg/kg): duck eggshell Pb 0.3607±0.065, Cd BDL, Cr BDL, Cu 0.0127±0.002, Fe 0.3115±0.053, Zn 0.035±0.005.
• Eggshells, Table 2 (mg/kg): quail eggshell Pb 0.18855±0.01, Cd BDL, Cr BDL, Cu 0.0265±0.0035, Fe 0.69875±0.082, Zn 0.03845±0.004.
• Eggshells, Table 2 (mg/kg): white layer chicken eggshell Pb 0.22185±0.057, Cd BDL, Cr BDL, Cu 0.0, Fe 0.2575±0.021, Zn 0.05375±0.003.
• Estimated dietary intake, Table 3 (mg/kg): chicken egg Pb 0.0020, Cd 0.0003, Cr 3.93x10-5, Cu 0.00042, Fe 0.0307, Zn 0.00619; chicken and duck egg Pb 0.0032, Cd Undetectable, Cr 5.03x10-5, Cu Undetectable, Fe 0.0473, Zn 0.0082.
• Table 4 reports target hazard quotients for Pb of 0.5714 for chicken egg and 0.9142 for chicken and duck egg; the source reports HI 0.0605 and 0.00109 for those rows respectively.

Methods (brief)

Egg and eggshell samples were collected in the Jahangirnagar University area (23°52'56.6"N 90°16'01.6"E) from local markets, washed, labeled, separated, dried in sunlight, and ground with a mortar. The authors weighed 1 gram of each sample powder, digested it with 25 ml of 65% HNO3, added 10 ml perchloric acid and later 2ml HCl, diluted with deionized water up to 60 ml, filtered the digest, and analyzed Pb, Cd, Cr, Cu, Fe, and Zn by atomic absorption spectrophotometry against standard curves. The source reports total chromium, not Cr(VI), and uses BDL without printing LOD/LOQ values in the extracted text.

Implications

Certification (HMTc): This is direct but small-n occurrence evidence for egg products in Bangladesh, with the strongest heavy-metal signal in Table 1 being Pb in quail egg. Eggshell values are useful context for eggshell-as-powder or eggshell exposure questions, but the edible egg-content rows are the relevant product occurrence values for ordinary eggs.

Courses: The paper is useful for teaching why BDL should remain as reported, why total Cr cannot be used as Cr(VI), and why egg contents and eggshells should not be collapsed into one food matrix.

App: The source can support Bangladesh-market egg contamination profiles for Pb, Cd, total Cr, Cu, Fe, and Zn, with a caution that species-specific ingredient routing is limited by the current closed slug vocabulary.

Wiki pages this source may touch

• lead
• cadmium
• chromium
• copper
• iron
• zinc
• eggs
• chicken
• poultry
• eggs-product
• poultry-product

Verification notes

• PDF text was extracted with pdftotext -layout to /tmp/mfk_june8_571.txt; the title block, abstract, Sampling, Method, Results prose, Tables 1-4, Discussion, and Conclusion were checked against this page.
• DOI 10.36348/sjbr.2022.v07i04.004, raw handle MFK_assessment-of-heavy-metals-and-trace-elements, and candidate cite-key path wiki/sources/rokanuzzaman2022-bangladesh-eggs-metals.md were checked before creation; no existing source page was found.
• Units and censoring are copied exactly as printed: concentration rows use mg/kg, and nondetects remain BDL or Undetectable according to the table. No conversions were performed.
• Speciation: the source reports Pb, Cd, Cr, Cu, Fe, and Zn by AAS. Chromium is total chromium; this page does not relabel it as Cr(VI).
• Brand firewall: the source reports local market egg types, not brands. No brand names are attached to values.
• Frontmatter slugs were checked against docs/gpt-collaboration/taxonomy-snapshot.md. The taxonomy lacks exact duck-egg and quail-egg ingredient/product slugs, so those species remain matrix descriptors and source text rather than invented slugs.

Page history

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