Overview
Zemanova, Pavlik, Pavlikova, and Kyjakova measured cadmium accumulation in spinach leaves grown in Chernozem soil amended with 0, 30, 60, or 90 mg cadmium (Cd)/kg soil. The study is routeable for spinach and leafy-vegetable cadmium context because it reports dry-matter leaf Cd concentrations and harvest timing, but it is not a retail-market occurrence survey. Its strongest use is evidence fitness for contaminated-soil sensitivity, growth-stage interpretation, and upper-bound Cd uptake behavior in spinach.
Key numbers
- Experimental design: spinach cv. Matador was grown in pots containing 5 kg Chernozem soil; Cd was added as Cd(NO3)2*4H2O at Cd1 = 30 mg/kg soil, Cd2 = 60 mg/kg soil, and Cd3 = 90 mg/kg soil, alongside an untreated control.
- Sampling times: spinach plants were sampled 25, 40, 55, and 75 days after sowing. Each treatment was performed in three replications every year, and the paper reports data averaged across two experimental years.
- Derived sample accounting for Cd/yield endpoints: four treatments x four harvest times x six replicate-year observations = 96 treatment-time pot observations, with 10 plants per pot after thinning. The source reports three replications every year, data averaged across two years, and Figure 1 caption gives n = 6 for treatment x growing-period means.
- Cadmium in leaves: the abstract reports Cd content in leaves from 0.60 to 72.38 mg/kg dry matter across the experiment.
- End-of-experiment response: at 75 days, increasing Cd soil dose was associated with aboveground dry-matter biomass declining from 23.5 g per pot to 6.3 g per pot, while leaf Cd rose to the reported maximum of 72.38 mg/kg dry matter.
- The paper reports that the Cd3 treatment reduced aboveground biomass to about 27% of the untreated control and increased Cd content in aboveground biomass up to 120-fold.
- The source reports amino-acid and fatty-acid responses to Cd stress, including elevated glutamic acid and aspartic acid through day 55 followed by declines at day 75 under Cd treatment. Those metabolism endpoints are context for plant stress response, not additional food-occurrence metals.
Methods (brief)
The authors cultivated spinach under natural light and temperature conditions at the Czech University of Life Sciences Prague. Soil moisture was controlled at 60% maximum water-holding capacity. For Cd analysis, plant samples were dry-ashed, ash was dissolved in 1.5% HNO3, and Cd was measured by ICP-OES using RM NCS DC 73350 poplar leaves as the certified reference material. Values are dry-matter plant-tissue concentrations; the paper does not provide a fresh-weight conversion. The source reports cadmium only for metal occurrence and does not provide arsenic, lead, mercury, chromium, nickel, or tin measurements.
Implications
Certification: The source is not a benchmark-pool retail occurrence source. It can support contaminated-soil sensitivity notes for spinach and leafy vegetables and should remain separated from market-sample pools unless a governance-approved contaminated-soil sensitivity pool is being built.
Courses: Useful for explaining why basis, cultivation setting, and experimental dosing must be recorded before comparing leafy-vegetable Cd values across studies.
App: Supports a contaminated-soil context warning for spinach, with explicit dry-matter and experimental-dose labels rather than ordinary-market risk language.
Related evidence
- Spinach
- Leafy Vegetables
- Non-root vegetables
- Spinach
- Leafy / Green Vegetables, Other
- Non-Root Vegetables
- Cadmium
Update history
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