Overview
Amjad and colleagues measured lead (Pb), nickel (Ni), cadmium (Cd), and chromium (Cr) in 30 locally available chocolate samples from Lahore, Pakistan. The study reports sample-level concentrations for each analyte after acid digestion and atomic absorption spectrophotometry. The paper is direct chocolate occurrence evidence, with values reported as ppm or mg/kg for finished chocolate samples.
Key numbers
Tables 2-5 report one concentration value per chocolate sample after triplicate analysis.
| Metal | n | Source-reported range | Highest sample | Source comparison |
|---|---|---|---|---|
| lead (Pb) | 30 | 0.375-3.400 mg/kg | SMSWLC-4 at 3.400 mg/kg | 27 of 30 samples exceeded the Punjab Food Rules value of 0.5 mg/kg cited by the authors. |
| nickel (Ni) | 30 | 0.005-2.050 mg/kg | MCK-18 at 2.050 mg/kg | 24 of 30 samples exceeded the Punjab Food Rules value of 0.025 mg/kg cited by the authors. |
| cadmium (Cd) | 30 | 0.50-3.50 mg/kg by Table 4 | KCS-13 at 3.50 mg/kg | The authors state 53% of samples exceeded the Punjab Food Rules value of 1.0 mg/kg. |
| chromium (Cr) | 30 | 0.005-0.280 mg/kg | CBCBCB-8 at 0.280 mg/kg | The authors state 53% of samples exceeded the Punjab Food Rules value of 0.02 mg/kg. |
The abstract summarizes Pb as 0.375-3.4 mg/kg, Ni as 0.005-0.28 mg/kg, Cr as 0.005-0.28 mg/kg, and Cd as 0.50-3.25 mg/kg. The detailed tables report Ni up to 2.050 mg/kg and Cd up to 3.50 mg/kg.
Methods (brief)
Samples were collected from local shops and markets in Lahore and digested before analysis by atomic absorption spectrophotometry at the Pakistan Council of Scientific and Industrial Research in Lahore. The paper reports triplicate analysis for each chocolate sample. The measured analytes are total Pb, total Ni, total Cd, and total Cr; no arsenic, mercury, tin, aluminum, uranium, or chromium speciation data are reported.
Implications
Certification: This source provides finished-chocolate occurrence data for Pb, Ni, Cd, and Cr in the Lahore retail market. It should be treated as Pakistan-market evidence and not silently pooled with US-market chocolate evidence without a market-basis decision.
Courses: Useful for teaching why finished-product chocolate surveillance needs multi-metal panels rather than cadmium-only screening.
App: Adds non-US finished-chocolate occurrence evidence for Pb, Ni, Cd, and total Cr.
Microbiome: Not addressed.
Related evidence
Update history
No substantive edit history is available in this build. The full commit record is available in git.