Heavy metals in wild mushrooms from contaminated areas

Abstract

Saprotroph and mycorrhizal fungi play an important role in forest ecosystem, particulary in the biogeochemical cycles. Saprotroph fungi are crucial for degradation of the organic matter. Mycorrhizal improve their hosts mineral nutrition. The mycorrhizal associations give resistance in contaminated areas to the plants. Sometimes inoculated plants hold up better the contamination that non-inoculated plants. The mycelia absorbs (extracts) the soil available fraction and decrease the heavy metal concentration in the plants. The fruit-bodies can be eaten by many animal specie as well as by humans. Some specie wild fungi have a high nutritional value and represent an important economical resource.

Soil, mushrooms and litter were sampled in a lead (Pb)-zinc (Zn) mine (Soria province, Spain). The distribution of metals in soil, litter and fungi shows a high concentration of metals in relation to the control areas. The Zn soil contents ranges are 797­3540 mg/kg, Cd: 2.1-10 mg/kg and Pb: 1485-8166 mg/kg, Litter content ranges: (Zn: 92-1475 mg/kg; Cd 0.9-4.2 mg/kg; Pb: 54-2756 mg/kg) and fruit-bodies ranges: (Zn 118-915 mg/kg; Cd: 1.2-45.2 mg/kg and Pb 12-1475 mg/kg). The bioacumulation factors show high environmental and toxicological risks.