Dandelion (Taraxacum officinale) often considered a weed is a highly versatile and beneficial plant that has been used in food, medicine, and as a natural remedy for centuries.
Soil pollution by potentially toxic elements is of concern since they may transfer to the edible parts of the food, especially when collecting wild plants from not cultivated, and thus not controlled soil. As examples, cadmium and lead are heavy metals that can accumulate in the body over time, leading to a range of adverse health outcomes.
The European Food Safety Authority (EFSA) stipulated maximum mass fractions of certain metals in food stuff, e.g. 0.05 mg/kg and 0.1 mg/kg for cadmium (Cd) and lead (Pb), respectively. Cadmium is primarily absorbed in the gastrointestinal tract when ingested through food. It is then distributed throughout the body, where it binds to proteins and accumulates in various tissues, particularly the kidneys, liver, and bones. Lead is absorbed into the body through the gastrointestinal tract and is distributed to the bloodstream, where it can accumulate in various tissues, including the bones, brain, and kidneys.
Dandelion and soil samples were collected at 19 different places in Croatia, divided into different parts (root, stem, leaf, flower); thus, generating a total of 95 samples. The plant parts were washed with diluted nitric acid, dried at 105 °C, and ground for homogenisation prior to acidic microwave assisted digestion. The quantification of selected potentially toxic elements in the clear digest solutions was carried out using inductively coupled plasma mass spectrometry (ICP-MS). Soil samples were air-dried and pulverized using an agate mortar prior to digestion and analysis. All plant samples had Pb mass fractions above the maximum value, the results ranging from 0.116 mg/kg to 2.39 mg/kg for the flowers, 0.272 mg/kg to 13.9 mg/kg for the leaves, 0.217 mg/kg to 3.56 mg/kg for the stem, and from 0.745 mg/kg to 40.4 mg/kg for the roots. Regarding Cd, all values except for flower and stem in two plants and four flowers exceeded the maximum mass fraction. On the contrast only five soils samples exceeded the World Health Organization (WHO) permissible limit of heavy metals in soil for Cd and only one for Pb.
The elevated levels of Cd and Pb in wild edible plants may pose a public health concern due to the exceedance of recommended limit values. In conclusion of this study, the present dandelion samples cannot be recommended for human consumption.
2025.