The mobility of arsenic and its species in selected herbs

Abstract

The aim of the study was verifi cation of the response of chamomile (Matricaria recutita (L.) Rauschert), peppermint (Mentha x piperita) lemon balm (Melissa offi cinalis L.), and sage (Salvia offi cinalis L.) on the elevated contents of inorganic As species in soils. The ability of herbs to accumulate arsenic was tested in pot experiment in which soils were contaminated by As(III) and As(V). The As(III), As(V), AB (arsenobetaine), MMA (monomethylarsonic acid) and DMA (dimethylarsinic acid) ions were successfully separated in the Hamilton PRP-X100 column with high performance-liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) techniques. The study examined total arsenic contents in soil and plants, as well as the mobility of the arsenic species from the soil into the studied plants. Peppermint demonstrated the highest arsenic concentration and phytoaccumulation among studied plants. The sequential chemical extraction showed that arsenic in the contaminated soil was mainly related to the oxide and organic-sulfi de fractions. The results showed that the oxidized arsenic form had a greater ability to accumulate in herbs and was more readily absorbed from the substrate by plants. Research has shown that soil contaminated with As(III) or As(V) has different effects on the arsenic content in plants. The plant responses to strong environmental pollution varied and depended on their type and the arsenic species with which the soil was contaminated. In most cases it resulted in the appearance of the organic arsenic derivatives.