Afrin 2020 — Heavy metals in retail fruits from Dhaka city, Bangladesh
Five fruit types (grape, apple, orange, banana, pomegranate) were collected from five retail outlets in Dhaka and analyzed for Pb, Cd, Cr, Ni, and Co by AAS. All measured concentrations were below FAO/WHO maximum allowable concentrations: Pb <1.50 mg/kg, Cd <0.20 mg/kg, Cr <2.30 mg/kg, Ni <0.80 mg/kg, Co <50 mg/kg. Concentration ranges were very low across all five locations, with little inter-site variation. Risk indices (single-factor pollution index, sum of pollution index, metal pollution index) all indicated the fruits posed no contamination risk under FAO/WHO reference values at the time of sampling.
Key numbers
Concentrations in mg/kg (all sites combined, typical ranges observed):
| Metal | Range across all fruits/sites | FAO/WHO MAC |
|---|---|---|
| Pb | 0.02–0.21 mg/kg | 1.50 mg/kg |
| Cd | 0.001–0.004 mg/kg | 0.20 mg/kg |
| Cr | 0.001–0.006 mg/kg | 2.30 mg/kg |
| Ni | 0.001–0.004 mg/kg | 0.80 mg/kg |
| Co | 0.001–0.003 mg/kg | 50.00 mg/kg |
Highest Pb at Kawran Bazar (banana, 0.21 mg/kg); highest single-factor pollution index for Pb was 0.14 (banana, Kawran Bazar). All pollution index values less than 1.0 indicate no contamination by FAO/WHO reference.
Note: Cr is measured as total chromium; speciation into Cr-VI vs. Cr-III was not performed.
Methods (brief)
AAS (method not fully specified beyond “atomic absorption spectroscopy”). Samples sun-dried, oven-dried, and ground before acid digestion. Quality assurance included CRD design with 3 replications. Study conducted at Sher-e-Bangla Agricultural University laboratory, 2018–2019 season. This is an M.S. thesis (evidence tier B: not journal peer-reviewed).
Implications
Certification: Pb and Cd concentrations in Dhaka retail fruits were well below FAO/WHO MACs; however, FAO/WHO limits are substantially more permissive than EU Regulation 1881/2006 limits (e.g., EU Pb limit for fruits is 0.10 mg/kg, not 1.50 mg/kg). Under EU limits, at least some Pb values from certain sites would warrant closer scrutiny.
Courses: Useful case study of a multi-fruit, multi-site survey in a South/Southeast Asian urban retail context; illustrates the importance of comparing against the applicable regulatory standard (FAO/WHO vs. EU limits give different compliance conclusions).
App: Low-level contamination profile for common retail fruits in Bangladesh. Confidence: low (M.S. thesis, single season, limited n per fruit per site).