Overview
Verma and Singh grew fenugreek and spinach at home in plain soil and in soil treated with 5 to 20 ppm of nickel, lead, chromium or cadmium, then measured each metal in leaf, stem, root and soil by ICP-MS. Plant levels rose with the soil treatment and were highest in roots for fenugreek. In plain soil, lead and cadmium were below quantification in every plant part of both crops.
Key numbers
- Spinach leaf, plain soil: lead and cadmium “BLQ”; at the 20 ppm treatment lead “0.8±0.004” and cadmium “1.10±0.9” ppm (Table 2).
- Spinach leaf chromium at the 20 ppm treatment “28.21±0.24” ppm (Table 2).
- Fenugreek root lead at the 20 ppm treatment “11.01±0.001” ppm; leaf “0.47±0.12” ppm (Table 1).
Methods (brief)
Washed plant parts (0.5 g wet ground weight) were microwave-digested in nitric acid and hydrogen peroxide and analysed by ICP-MS with internal standards. How the soil treatments were applied, the number of replicates and the quantification limit are not stated, and no reference material or recovery data are shown.
Evidence Fitness
An experimental spiked-soil pot study, not an occurrence survey: only the plain-soil control reflects ordinary growing, and there lead and cadmium were below quantification. Reporting is poor (one unparseable cell, very large errors on some means, claims of good recovery without data). Fresh leafy vegetables are a proxy for the non-root vegetable purees page, not purees.