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Straw mushrooms were grown on lead contaminated rice straw and stubble. Study materials were dried, acid digested, and analyzed for lead using flame atomic absorption spectrophotometry. The results showed the highest lead concentration in substrate was 445.350 mg kg−1 in Treatment 3 (T3) and the lowest was BD (below detection) in Treatment 1 (T1). The maximum lead content in straw mushrooms was 5.072 mg kg−1 dw in pileus of T3 and the minimum lead content in straw mushrooms was BD in egg and mature (stalk and pileus) stage of T1. The lead concentration in straw mushrooms was affected by the age of the mycelium and the morphology of mushrooms. Mushrooms’ lead uptake produced the highest accumulation in the cell wall. Some lead concentrations in straw mushrooms exceeded the EU standard (>3 mg kg−1 dw).

A greenhouse study was conducted to observe the localization of lead in narrow-leaved cattail, Typha angustifolia. Light and transmission electron microscopic studies were performed on root, rhizome and leaf of the cattail grown in control (75 kg dry weight of soil with no added lead) and in the same weight of soil amended with 20,000 mg lead nitrate. At 15 and 90 days after planting, most lead was accumulated in root cells around vacuoles and slowly transported to leaves. In the lead-contaminated soil, parts of the root cell wall were damaged at the end of the experiment. Lead was deposited in the rhizome near the cell wall. Similar deposits were observed in the roots and rhizomes suggesting that lead was transported and localized in a similar area, whereas the leaf cells accumulated lead in the chloroplasts.

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