Heavy Metals and Associated Risks of Wild Edible Mushrooms Consumption: Transfer Factor, Carcinogenic Risk, and Health Risk Index

Abstract

This research aims to investigate the heavy metals (i.e., Cd, Cr, Cu, Ni, and Pb) in the fruiting bodies of six indigenous wild edible mushrooms including Agaricus bisporus, Agaricus campestris, Armillaria mellea, Boletus edulis, Macrolepiota excoriate, and Macrolepiota procera, correlated with various factors, such as the growth substrate, the sampling site, the species and the morphological part (i.e., cap and stipe), and their possible toxicological implications. Heavy metal concentrations in mushroom (228 samples) and soil (114 samples) were determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). In the first part of the study, the soil contamination (index of geo-accumulation, contamination factor, and pollution loading index) and associated risks (chronic daily dose for three exposure pathways-ingestion, dermal, and inhalation; hazard quotient of non-cancer risks and the carcinogenic risks) were calculated, while the phytoremediation capacity of the mushrooms was determined. At the end of these investigations, it was concluded that M. procera accumulates more Cd and Cr (32.528% and 57.906%, respectively), M. excoriata accumulates Cu (24.802%), B. edulis accumulates Ni (22.694%), and A. mellea accumulates Pb (18.574%), in relation to the underlying soils. There were statistically significant differences between the stipe and cap (i.e., in the cap subsamples of M. procera, the accumulation factor for Cd was five times higher than in the stipe subsamples). The daily intake of toxic metals related to the consumption of these mushrooms with negative consequences on human health, especially for children (1.5 times higher than for adults), was determined as well.

Keywords: Bucegi National Reservation; carcinogenic risk; daily intake metals; estimated daily intake; health risk index; industrial area; touristic area; transfer factor; wild edible mushrooms.

Figure 1

Sampling sites.

Figure 2

Index of geo-accumulation calculated for the analyzed soil samples.

Figure 3

Contamination factor (CF—empty squares) and pollution loading index (PLI—red full square) of the heavy metals within the studied area.

Figure 4

The transfer factor in cap (a) and stipe subsamples (b).

Figure 5

Pearson correlations between the soil samples in terms of HMs content combined with hierarchical cluster analysis.

Figure 6

Pearson correlations between the mushroom cap subsamples in terms of HMs content combined with hierarchical cluster analysis.

Figure 7

Pearson correlations between the mushroom stipe subsamples in terms of HMs content combined with hierarchical cluster analysis.