Researchers mixed twelve edible-plant extracts with lead-nitrate solution and measured lead remaining in the centrifuged liquid. The results document a laboratory treatment experiment. They do not measure lead in the original foods, and the reported removal percentages use an undiluted control despite a twofold dilution in each treatment.
Key numbers
| Measurement | Source-reported result | Location and qualification |
|---|---|---|
| Experimental groups | Twelve plant extracts, each tested in triplicate | Methods pp723–724; reaction replicates do not establish independent market samples. |
| Reaction mixture | 25 mL stock plus 25 mL extract | Methods p724; a dilution-only control was also measured. |
| Undiluted/diluted controls | 1,277/710 ppm | Tables 1–3; source-labelled Pb concentration, stock preparation basis unresolved. |
| Collard-green-treated liquid | Mean 2.4 ppm, SD 0.015, SE 0.0088 | Table 1; residual liquid, not collard-green tissue. |
| Carrot-treated liquid | Mean 20.6 ppm, SD 0.61, SE 0.35 | Table 2; table removal 98% conflicts with 95.5% in abstract/conclusion. |
| Lime-treated liquid | Mean 540.8 ppm, SD 70.7, SE 40.82 | Table 3; source removal 57.6% uses the undiluted control. |
Means, standard deviations, standard errors and reported percentages are retained for all treatments and both controls. Repeated controls and chart labels do not create additional independent observations.
Methods (brief)
Store- or market-purchased plants and garden bitter leaf were pureed with deionized water, filtered and centrifuged. Triplicate extract/lead-solution mixtures were shaken at room temperature, then centrifuged again. A commercial laboratory measured the liquid by EPA Method 6010 ICP-AES. Methods state 24 hours, while the abstract says 22 hours. Collection dates, plant origins and numerical detection limits are not supplied.
Evidence fitness
Supports qualified laboratory-method context and source-reported residual-liquid summaries. The analyzed material was treated water, so these values cannot establish impurity levels in food ingredients or retail wipes. The experiment does not demonstrate drinking-water safety, clinical benefit or field-scale remediation.
Limitations
The paper describes 1.3 g of lead nitrate in 1 litre as 1,300 ppm lead without resolving compound versus elemental concentration. Removal percentages compare diluted treatment mixtures with the undiluted control, confounding dilution with treatment. Several abstract, conclusion, table and chart numbers disagree. These original values remain distinct; no replacement efficacy calculation is presented.
Reaction triplicates do not demonstrate reproducibility across independent plant lots. The paper supplies no complete liquid/solid mass balance, measured acidity, extract-blank results or detailed recovery data. Consequently, the proposed acidity explanation and removal mechanism remain uncertain.
Related evidence
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