Background: There is an interest in developing cheaper and effective methodologies for air pollution monitoring. Thus, biological materials such as plants and animals accumulators of metals have been studied for use in biomonitoring of air pollution. The plant chosen for biomonitoring in the present study was the Tradescantia pallida var. Purpurea (T. pallida). The harmful effects of environmental pollution have been already evidenced by micronucleus assays using the species T. pallida. Three Brazilian studies identified accumulation in leaves of T. pallida of important elements for air pollution biomonitoring using neutron activation analysis. Here, a new methodology using atomic emission spectroscopy with inductively coupled plasma was evaluated.
Methods: Two samples of T. pallida were collected from different sampling points in the city of Sao Paulo. The two plant samples were analyzed by atomic emission spectroscopy with inductively coupled plasma to determine the concentrations of the heavy metals cadmium, lead, lithium, nickel, zinc, cobalt and manganese in the leaves of the species T. pallida.
Results: Making a comparison between concentrations of elements found in the two samples, Mn and Zn appeared in greater quantity in sample 1 (the collection point was a sidewalk next to an avenue with intense traffic of cars - metropolitan region Sao Paulo) than in sample 2 (residential neighborhood - metropolitan region Sao Paulo). Most of the concentrations of the elements were similar and appeared above the detection level of the device (ICP-AES) Spectro Ciros CCD.
Conclusions: All metals were detected in the dry biomass of the plants which brings more elements to the study of this species as a bioindicator of environmental pollution. Here we can not say if the metals were absorbed by the roots or by aerial parts, but establish the levels of these metals in such kind of plant with this methodology can be useful for further studies.
Keywords: Tradescantia pallida , heavy metals , environmental pollution