Arsenic concentrations and associated health risks in Laccaria mushrooms from Yunnan (SW China).

Some species of Laccaria have been known to contain relatively high levels of arsenic in Europe and are used as edible mushrooms in the southwest China. One population of Laccaria proxima and one population of L. vinaceoavellanea as well as topsoil (0-10 cm) they grew on were collected from natural habitats of Yunnan (SW China), while other samples such as Laccaria mushroom samples without soil were purchased from four different local markets in Yunnan. Concentrations of arsenic were determined in fruit bodies of the mushrooms and in the soils by using atomic fluorescence spectrometry to assess potential health risks of these species. The mean arsenic concentrations in caps were 135, 14.1-143, 5.5 and 130-163 mg kg(-1) dry weight (dw) for Laccaria amethystina, Laccaria laccata, L. proxima and L. vinaceoavellanea, respectively. The mean value for bioconcentration factor of arsenic in caps of L. vinaceoavellanea was 29.1 for soil with arsenic content at 5.6 mg kg(-1) dw, which indicate that L. vinaceoavellanea is an accumulator for arsenic. Caps of L. amethystina, L. laccata and L. vinaceoavellanea consumed at a volume of 300 g fresh weight for a single meal in a week can yield an exposure amount of arsenic at 4.1, 0.42-4.3 and 3.9-4.9 mg, respectively. These values are higher than the limit dose for the intake of inorganic arsenic recommended by the Joint FAO/WHO Expert Committee on Food Additives.