Accumulation of heavy metals in native Andean plants: potential tools for soil phytoremediation in Ancash (Peru)

• Published in: Environmental science and pollution research international 2018-12, Vol.25 (34), p.33957-33966
• Main Authors: Chang Kee, José, Gonzales, María J., Ponce, Olga, Ramírez, Lorena, León, Vladimir, Torres, Adelia, Corpus, Melissa, Loayza-Muro, Raúl
• Format: Article
• Language: English
• Subjects: Achyrocline alata; Acidification; Alfalfa; Aquatic plants; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Bioaccumulation; Biodegradation, Environmental; Cadmium; Calamagrostis recta; Contamination; Controlled conditions; Copper; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental liability; Environmental quality; Environmental Restoration and Remediation - methods; Environmental science; Flowers & plants; Heavy metals; Indigenous plants; Indigenous species; Juncus bufonius; Lead; Liabilities; Mathematical analysis; Medicago lupulina; Metal concentrations; Metals; Metals, Heavy - analysis; Metals, Heavy - pharmacokinetics; Mine tailings; Mine wastes; Mining; Nickel; Pennisetum clandestinum; Peru; Phytoremediation; Plant Roots - chemistry; Plant Roots - drug effects; Plant Roots - metabolism; Plant Shoots - drug effects; Plant Shoots - metabolism; Plant species; Plants - drug effects; Plants - metabolism; Polluted environments; Propagation; Public health; Quality standards; Research Article; Roots; Shoots; Soil conditions; Soil contamination; Soil Pollutants - analysis; Soil Pollutants - pharmacokinetics; Soils; Tailings; Translocation; Waste Water Technology; Water Management; Water Pollution Control; Werneria nubigena; Zinc
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-018-3325-z

Metal contamination is a recurring problem in Peru, caused mainly by mine tailings from a past active mining activity. The Ancash region has the largest number of environmental liabilities, which mobilizes high levels of metals and acid drainages into soils and freshwater sources, posing a standing risk on human and environmental health. Native plant species spontaneously growing on naturally acidified soils and acid mine tailings show a unique tolerance to high metal concentrations and are thus potential candidates for soil phytoremediation. However, little is known about their propagation capacity and metal accumulation under controlled conditions. In this study, we aimed at characterizing nine native plant species, previously identified as potential hyperaccumulators, from areas impacted by mine tailings in the Ancash region. Plants were grown on mine soils under greenhouse conditions during 5 months, after which the concentration of Cd, Cu, Ni, Pb, and Zn was analyzed in roots, shoots, and soils. The bioaccumulation (BAF) and translocation factor (TF) were calculated to determine the amount of each metal accumulated in the roots and shoots and to identify which species could be better suited for phytoremediation purposes. Soil samples contained high Cd (6.50–49.80 mg/kg), Cu (159.50–1187.00 mg/kg), Ni (3.50–8.70 mg/kg), Pb (1707.00–4243.00 mg/kg), and Zn (909.00–7100.00 mg/kg) concentrations exceeding national environmental quality standards. After exposure to mine tailings, concentrations of metals in shoots were highest in Werneria nubigena (Cd, 16.68 mg/kg; Cu, 41.36 mg/kg; Ni, 26.85 mg/kg; Zn, 1691.03 mg/kg), Pennisetum clandestinum (Pb, 236.86 mg/kg), and Medicago lupulina (Zn, 1078.10 mg/kg). Metal concentrations in the roots were highest in Juncus bufonius (Cd, 34.34 mg/kg; Cu, 251.07 mg/kg; Ni, 6.60 mg/kg; Pb, 718.44 mg/kg) and M. lupulina (Zn, 2415.73 mg/kg). The greatest BAF was calculated for W. nubigena (Cd, 1.92; Cu, 1.20; Ni, 6.50; Zn, 3.50) and J. bufonius (Ni, 3.02; Zn, 1.30); BCF for Calamagrostis recta (Cd, 1.09; Cu, 1.80; Ni, 1.09), J. bufonius (Cd, 3.91; Cu, 1.79; Ni, 18.36), and Achyrocline alata (Ni, 137; Zn, 1.85); and TF for W. nubigena (Cd, 2.36; Cu, 1.70; Ni, 2.42; Pb, 1.17; Zn, 1.43), A. alata (Cd, 1.14; Pb, 1.94), J. bufonius (Ni, 2.72; Zn, 1.63), and P. clandestinum (Zn, 1.14). Our results suggest that these plant species have a great potential for soil phytoremediation, given their capability to accumulate and transfer met