Overview
The authors bought five leafy or stem vegetables in five Jos markets, pooled them into one composite per vegetable, and measured eight metals by graphite furnace AAS after air-drying. They also estimated daily intakes and hazard quotients. The concentration figure and tables are missing from this PDF, so only the values quoted in the results text can be used.
Key numbers
- Celery: cadmium 0.095 ± 0.006 mg/kg and arsenic 0.185 ± 0.005 mg/kg, the highest of the five vegetables (Section 3.1, p. 3).
- Kenaf: arsenic 0.160 ± 0.017 mg/kg (Section 3.1).
- Sesame leaves: lead 0.025 ± 0.004 mg/kg, the lowest lead value (Section 3.1).
Methods (brief)
Vegetables were washed, air-dried for two weeks and ground; 0.2 g was digested in perchloric and nitric acid and read by graphite furnace AAS in triplicate. No reference material, recovery or detection limit is reported.
Evidence Fitness
One composite per vegetable, no quality-control data and no collection dates. Figure 1 and Tables 3 to 5 are absent from the published PDF, so most metal and vegetable pairs are unavailable. The daily intake values in Section 3.2 are 1000 times what the printed concentrations imply, so a unit is mislabeled somewhere; the extracted values carry an integrity flag. Celery and spring onion bear directly on non-root vegetables.