Bioaccumulation of Toxic Metals from Trace Metals Polluted Soils Using Five Species of Mushroom Found in Anambra State, Nigeria

Abstract:

The aim of the study was to provide base-line data on five mushroom species and determine their potential for remediation of metal polluted soil in Anambra State, Nigeria. Five species of Mushroom namely Termitomyces robustus, Agaricus bisporus, Pleurotus tuber-regium, Amanita phalaoides and Amanita verosa were collected from eleven locations in Uke, Abatete, Ideani, Nnobi, Nnewi (Okpuno-egbu), Nnewi (Umudim) and Ozubulu between 2012 and 2016 in Anambra State, Nigeria. They were kept in clean collection bags and identified by a taxonomist. Some of the mushroom samples were later oven dried at 75 0 C for 4 h and kept for chemical analysis while some were used for cultivation. During cultivation, seeds from matured mushrooms were scrapped from their veils into already compounded substrates/soil from their natural habitats and refuse dump soil. The seeds were allowed to germinate within 4-5 days, the fruiting bodies/spawns were watered once daily for 14 days. The matured mushrooms were harvested, cleaned and oven dried at 75 0 C for 4 h. The dried mushroom samples (wild and cultivated respectively) were homogenized into a fine powder using a blender with titanium blade and stored in pre-cleaned bottles for chemical analysis. These samples were subjected to various chemical analyses using standard methods by the Association of Official Analytical Chemist (AOAC). The data were subjected to one-way analysis of variance (ANOVA) at 95 % level using Statistical Package for Social Scientists (SPSS) version 16.0. Bioaccumulation factors ranged as follows: Cd (0.14 -1.78), Co (0.06 – 3.01), Cr (BDL), Cu (0.01 – 0.35), Fe (1.17 -2.22), Mn (0.38 – 13.53), Ni (0.08 – 1.95), Pb (0.08 – 1.50) and Zn (0.22 – 10.13). The obtained values were above the acceptable limit in food.