Response of chamomile Matricaria recutita to low and moderate soil cadmium pollution
The aim of this study was to evaluate the effects of soil cadmium (Cd) pollution to the growth and quality of medicinal herbs plant chamomile (Matricaria recutita L.) and their extracts. The plants were grown in soils contaminated with Cd (3, 6, 12 mgCd/kg) for four weeks. The morphological, physiological, biochemical parameters and the content of Cd in chamomile tissues and infusions were determined. The results of this study showed that soil contamination with Cd had no adverse effect to the aboveground biomass of chamomile, but slightly reduced root biomass. Cd treatment significantly reduced the number of flowers and their dry weight. Cd soil pollution had no significant adverse effect on the content of photosynthetic pigments, though induced lipid peroxidation and an increase in MDA content was recorded. Cadmium concentrations in the plant tissues and extracts increased along with Cd concentration in the soil. It was found that Cd concentrations in chamomile flowers and infusions were above the maximum allowable Cd levels in medicinal plants and drinking water. This study demonstrated that the use of chamomile products may pose a risk to human health even if chamomiles are growing at environmentally relevant Cd soil concentration.