Arsenic speciation of commonly eaten mushrooms from central Europe

Abstract

Environmental context With mushroom consumption increasing worldwide, it is important to know about the concentration of different arsenic species in the most commonly eaten mushroom species, especially since the toxicity depends on the chemical structure. No dangerous amounts of the highly toxic inorganic arsenic were detected in the studied mushrooms. It is therefore safe to consume mushroom fruit-bodies of the investigated species, at least with regard to the arsenic content.Rationale A large variety of different mushroom species is considered edible. They are often considerably distinct from each other in a wide range of properties, among others the elemental profile and the speciation of various elements, e.g. arsenic.Methodology In this first comprehensive study of arsenic and its species in the most popular cultivated and wild-grown edible mushrooms in central Europe, the arsenic mass fraction and the arsenic speciation of a total of 93 mushroom samples were investigated with inductively coupled plasma mass spectrometry (ICPMS) and high performance liquid chromatography coupled to ICPMS.Results The arsenic mass fractions ranged from <0.004 to 1.02 mg kg−1 dry mass. For some mushroom species (e.g. Cantharellus cibarius), only low amounts of the total arsenic could be extracted with water, and other mushrooms revealed unusual arsenic speciation profiles and the presence of compounds that are rarely found in the terrestrial environment, for example dimethylarsinoylacetic acid, accounting for around 12% of the total arsenic in Boletus edulis. Over all, the results highlight the diversity of arsenic species in mushrooms, but also reveal a high consistency within the individual mushroom species.Discussion With mushroom production increasing each year, it is important to know the content of possibly dangerous compounds. The toxic inorganic arsenic was generally below 0.2 mg kg−1 dry mass. Considering the maximum limit that can be eaten of inorganic arsenic without increased health risk, at least 2 kg of the studied mushrooms could be consumed by an average person per day on a regular basis.