Chemical and cytotoxical changes in leaves of Eugenia uniflora L., a medicinal plant growing in the fourth largest urban centre of Latin America

Characteristics of the urban environment are sufficient to alter the degree of cytotoxicity of the extract obtained from the leaves of Eugenia uniflora L. Most people in urban environments obtain medicinal plants through their own cultivation. Eugenia uniflora L. is a native shrub of Brazilian restinga that is common in urban areas. The population commonly uses the leaves to treat various diseases, and the Brazilian National Health Service recommends this species. Thus, research is needed to assess the toxicity of medicinal products derived from this plant grown in urban environments and to determine its reliability for use by the population. Therefore, this study evaluated leaves of E. uniflora grown in an urban environment to identify possible chemical and cytotoxical changes. This study presents an integrated analysis of the environmental conditions, physiology and phytochemistry of E. uniflora, in addition to experiments that evaluate the toxic potential of its extract. Chemical analysis of soil and leaves revealed great variation in the plant’s capacity to accumulate chemical elements. Among the chemical elements analysed, lead stands out as it was detected at the concentration limit allowed by World Health Organization in leaves from an urban site. Results of the cytotoxicity analysis revealed significant differences regarding the viability of VERO cells submitted to extract. We suggest that environmental and soil characteristics of the urban site are responsible, at least in part, for the cytotoxic characteristic of E. uniflora leaf extract.