Overview
Usman et al. grew Pleurotus tuberregium mushrooms on four substrate types in Aba, Nigeria and analyzed cadmium (Cd), chromium (Cr), and lead (Pb) in the harvested fruiting bodies. The study is useful as mushroom occurrence evidence because it reports a direct food matrix with substrate metadata. All three target metals were below the detection limit in mushrooms grown on the tested substrates.
Key numbers
| Finding | Source-reported value |
|---|---|
| Substrates | Topsoil, sawdust, riversand, and riversand-sawdust mixture |
| Replicates | Four replicates per substrate |
| Metals analyzed | Cd, Cr, Pb by atomic absorption spectrophotometry |
| cadmium (Cd) in harvested mushrooms | BDL for all used substrates |
| chromium (Cr) in harvested mushrooms | BDL for all used substrates |
| lead (Pb) in harvested mushrooms | BDL for all used substrates |
| Riversand fruiting bodies | Highest mean stipe height, widest mean pileus, and highest yield |
| Proximate range | Protein 16.10 to 17.15 percent; ash 3.68 to 6.68 percent across reported substrates |
Methods (brief)
The study planted Pleurotus tuberregium sclerotia into 500 g portions of four substrates under laboratory conditions. Fruiting-body growth and proximate composition were measured. For heavy metals, dried mushroom samples were acid-digested and Cd, Cr, and Pb were measured using an Agilent FS240AA atomic absorption spectrophotometer.
The heavy-metal results are nondetects. The PDF text layer does not expose numeric detection limits, so this page records the censoring status without inventing substitute values.
Implications
For mushroom ingredient pages, this paper contributes a Nigeria-specific nondetect finding for Cd, Cr, and Pb in Pleurotus tuberregium grown under the tested substrate conditions. It is not evidence that all mushrooms or wild mushrooms are low in these metals, because the study was species- and substrate-specific.
Related evidence
Update history
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