Matloob 2016 — heavy metals in cooking spices used in Iraq

Matloob measured ten elements in 160 samples representing 32 natural spices traditionally consumed in Iraq. The paper is direct spice occurrence evidence, with dry-weight concentration tables for essential trace elements and toxic elements.

Key numbers

• Sampling: 32 spice types, five samples per spice, purchased from shops and supermarkets in Babil, Iraq.
• Dry-weight concentration ranges across the 32 spice types were Cu 2.58-30.71 mg/kg, Zn 5.45-129.3 mg/kg, Fe 32.44-1147 mg/kg, Mn 6.42-285.8 mg/kg, Cr 0.052-1.317 mg/kg, Ni 0.280-5.900 mg/kg, Co 0.020-0.754 mg/kg, Cd 0.011-1.389 mg/kg, Pb 0.250-4.159 mg/kg, and Hg 0.032-2.870 mg/kg.
• Mean dry-weight concentrations across spice types were Cu 10.50 mg/kg, Zn 44.21 mg/kg, Fe 267.4 mg/kg, Mn 58.60 mg/kg, Cr 0.480 mg/kg, Ni 1.560 mg/kg, Co 0.232 mg/kg, Cd 0.171 mg/kg, Pb 0.968 mg/kg, and Hg 0.400 mg/kg.
• Highest reported toxic-element examples included Cd 1.389 +/- 0.152 mg/kg in tamarind fruit pulp, Pb 4.159 +/- 0.943 mg/kg in cinnamon bark, and Hg 2.870 +/- 1.320 mg/kg in coriander seed.
• Turmeric rhizomes were reported at Cd 0.227 +/- 0.130 mg/kg, Pb 0.387 +/- 0.101 mg/kg, Hg 0.076 +/- 0.021 mg/kg, Cr 0.500 +/- 0.115 mg/kg, and Ni 0.683 +/- 0.200 mg/kg.
• Black pepper fruit was reported at Cd 0.093 +/- 0.050 mg/kg, Pb 0.317 +/- 0.157 mg/kg, Hg 0.311 +/- 0.087 mg/kg, Cr 1.044 +/- 0.424 mg/kg, and Ni 4.904 +/- 1.618 mg/kg.

Methods (brief)

The study used dry ashing followed by analysis with anodic, cathodic, and adsorptive stripping voltammetry on a Metrohm 797 VA Trace Analyzer. The author used standard additions for quantification. Samples were washed, dried at 80 degrees C for 24 hours, ashed at 550 degrees C, dissolved in 0.25 percent nitric acid, diluted to 50 mL, and analyzed immediately.

The reported basis is dry spice weight. Mercury is reported as total Hg; chromium is total chromium.

Implications

Certification: This is benchmark-relevant occurrence evidence for the spices product row on a dry-weight basis. It supports Iraq-market stratification and should not be silently pooled with US-market spice lots without a market rationale.

Courses: The paper is a compact example of broad multi-spice metals surveillance, with both essential trace elements and non-essential toxic elements in the same analytical workflow.

App: Ingredient-level signals are strongest for spices as a broad category, with item-level entries for turmeric and black pepper where the wiki already has ingredient pages.

Wiki pages this source may touch

• spices
• spices
• turmeric
• black-pepper
• cadmium
• lead
• mercury
• chromium
• nickel

Verification notes

• The PDF uses “Tumeric” in Table 5 and Table 6; this source page routes that row to turmeric.
• Concentrations are mg/kg dry weight, equivalent to ppm and to micrograms per gram.
• The study reports total chromium and total mercury; it does not provide Cr(VI), inorganic arsenic, or methylmercury speciation.

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.