Is it safe to consume medicinal plants in mined areas? Investigating possible effects caused by a metal-contaminated plant in southern Brazil

Abstract

Mineral extraction areas are a significant environmental concern due to soil, water, and plant food resources contamination. Some medicinal plant species, such as those of the genus Baccharis, potentially bioaccumulate toxic elements. We evaluate the metal content from coal mining activity present in Baccharis sagittalis and in the soil; and whether this plant consumption represents a risk to human health. Cd and Pb presented levels that exceed those recommended by three global health agencies. Cd and Pb showed high levels in the projections of the daily intake recommended by international health agencies. After interviewing local residents close to mining areas, we found that 53.8 % of the interviewees mentioned the consumption of Baccharis sagittalis as infusion. These results indicate that the consumption of metal-contaminated Baccharis sagittalis can cause health problems as those metals accumulate in the human body. However, studies on Al, Ba, Cr, Cu, Mn, Ni, and Zn acceptable levels in plants consumed by humans are scarce. The contamination of plant species with associated traditional use close to mining areas can increase food security vulnerability of people who live near those areas and are constantly exposed to these agents, using plants gathered in the region.