Summary
This study measured concentrations of arsenic, lead, cadmium, chromium, iron, and copper in nine commonly consumed vegetables and their paired soils from nine integrated farms across four Upazilas in Noakhali district, Bangladesh. All samples were collected directly from local farms in 2024 to 2025. Metal concentrations were analyzed by atomic absorption spectrophotometry (AAS) using a Perkin-Elmer novAA 400p instrument. Among the nine vegetable types, bitter gourd, lady finger, and pumpkin showed the highest metal accumulation; eggplant showed the lowest. The ascending order of mean concentrations across all matrices was: arsenic less than lead less than cadmium less than chromium less than iron less than copper.
Key numbers
| Measure | Value | Units | Matrix | Source location |
|---|---|---|---|---|
| Highest mean lead | 4.78E-03 | mg/kg fresh weight | Bitter gourd | p. 5, Table 2 |
| Estimated daily intake, arsenic | 0.0736 | mg/day (adult) | Vegetable consumption | p. 5, Table 3 |
| Estimated daily intake, lead | 2.4128 | mg/day (adult) | Vegetable consumption | p. 5, Table 3 |
| Estimated daily intake, cadmium | 0.3644 | mg/day (adult) | Vegetable consumption | p. 5, Table 3 |
| Estimated daily intake, chromium | 0.01098 | mg/day (adult) | Vegetable consumption | p. 5, Table 3 |
| Estimated daily intake, iron | 12.4201 | mg/day (adult) | Vegetable consumption | p. 5, Table 3 |
| Estimated daily intake, copper | 0.5712 | mg/day (adult) | Vegetable consumption | p. 5, Table 3 |
| Cancer risk, lead in bitter gourd | 2.32 × 10^-3 | dimensionless | Bitter gourd | p. 5 |
| Cancer risk, chromium in bitter gourd | 2.32 × 10^-3 | dimensionless | Bitter gourd | p. 5 |
| Cancer risk, cadmium in lady finger | 5.47 × 10^-4 | dimensionless | Lady finger | p. 5 |
The lead and cadmium concentrations in bitter gourd and lady finger exceeded FAO/WHO permissible limits. All lead (Pb) mean values and several cadmium (Cd) and chromium (Cr) mean values exceeded WHO reference limits, while arsenic, iron, and copper concentrations were near permissible limits (p. 5). Cancer risk values for lead in bitter gourd (1.37 × 10^-3 to 1.79 × 10^-3) exceeded the USEPA threshold of 10^-4.
Methods (brief)
54 samples collected (9 vegetable types, 3 replicate samples per type from 9 farms, 1 of each per farm, plus soil). Wet digestion using 1:4 concentrated HNO3/H2SO4. AAS analysis with standards at 1000 ppm. Recovery 90 to 110%. LOD 0.01 ppm/mL. Sampling year 2024 to 2025.
Evidence fitness
This is a small-scale study (n = 54 total) from integrated farms in a single district. The farms were purposively selected based on local dietary patterns, not random market sampling, so values may not represent market-level distributions. The cadmium and lead exceedances above FAO/WHO limits are from the same high-contamination farms and reflect local soil conditions. The EDI estimates are suitable for the Noakhali-specific population context, not for broader market benchmarking.
Limitations
Single district, non-random farm selection, dry-weight basis for concentrations but EDI computed on fresh-weight basis (conversion assumed but not stated explicitly). No CRM recovery values reported. Sample size is small (3 replicates per vegetable type).
Related evidence
Update history
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