Environmental trace metals contamination near a copper mining area from central-west region of Romania

The rising global demand for metals has intensified mining operations, resulting in considerable environmental pollution by heavy metals in soils and water bodies, which endangers ecosystems and human health. While heavy metals are naturally present in soils and aquatic environments, human activities such as mining and smelting have significantly disrupted their biogeochemical cycles, causing increased concentrations that pose threats to both the environment and public health. This study focuses on assessing the levels of trace and heavy metals in river water and soils in a Romanian copper mining region, as well as examining their bioaccumulation in soils, aquatic organisms, and plants. The findings aim to provide essential data to support environmental management and remediation efforts.

This study examines environmental metal contamination in the vicinity of a copper mining area located in the Central-West Region of Romania. Samples-including water, mud, soil, fish, and Salix alba leaves-were collected from upstream (UPS), downstream (DWS), and the confluence point (RJ) of the Aries and Abrud rivers within Alba County. Sampling sites encompassed various locations near the mining operations along the river, as well as a reference site approximately 200 km southwest (SW) in a non-mining area. All samples were analyzed using a PerkinElmer AAPinacle 900 T atomic absorption spectrometer. Additionally, concentration factors and pollution load indices for water, mud, and soil were calculated, along with bioaccumulation factors for fish and Salix alba leaves.

Our analyses revealed elevated levels of copper (Cu), iron (Fe), and zinc (Zn) exceeding Romanian water quality standards, while mercury (Hg), cadmium (Cd), and lead (Pb) remained below standard thresholds. The contamination factor (CF) indicated higher concentrations of Cu, Zn, Fe, Hg, Cd, and Pb in the mining vicinity compared to non-mining areas, with increased CF observed downstream and at the river junction, suggesting significant pollutant dispersion. The pollution load index (PLI) corroborated these findings, showing elevated pollution levels in water, soil, and mud samples near the mining site. Bioaccumulation assessments demonstrated a bioconcentration factor (BAF) greater than one for Hg, Cd, and Pb in Salix alba leaves from all sampling points, indicating bioaccumulation, whereas Fe exhibited lower BAF values. In fish, BAFs for Cu, Zn, Hg, and Pb exceeded one across all areas, confirming accumulation, while Fe showed limited bioaccumulation. Notably, cadmium bioaccumulation was detected only upstream and at the river junction, with no accumulation downstream.

These findings highlight the impact of copper mining activities on environmental metal distribution and bioaccumulation in local biota, underscoring the need for ongoing monitoring and mitigation strategies to protect ecological and human health.