Bioaccumulation of heavy metals in mesozooplankton from a human impacted south western Atlantic estuary (Argentina)

VILLAGRAN DIANA MARIEL; FERNÁNDEZ SEVERINI MELISA DAIANA; BIANCALANA FLORENCIA; SPETTER CARLA VANESA; FERNANDEZ ELEONORA; JORGE EDUARDO MARCOVECCHIO

JOURNAL OF MARINE RESEARCH

SEARS FOUNDATION MARINE RESEARCH

Lugar: New York; Año: 2019

0022-2402

The total metal concentrations (Cd, Cu, Pb, Zn, Mn, Ni, Cr and Fe) in the mesozooplankton (200 μm-2 mm) were studied for a year in a human impacted estuary strongly affected by urban and industrial discharges, located in the South Atlantic. Over the last 25 years, this estuary has been the site of significant anthropogenic impacts including industrial activities, maritime traffic and regular dredging. A quantitative and qualitative analysiswas also carried out to identify the mesozooplanktonic community that was sampled for metal determinations. The mesozooplankton had high concentrations of toxic metals such as Cd, Pb, Cr and Ni, which may indicate that theseorganisms are strong accumulators of these metals. Also, the analyzed metals had a wide temporal variation, the highest levels being in autumn and spring. The ranges were: Cd: 0.3-3.8; Cu: 35.3-226.6; Cr: 1.4-57.9; Fe: 1060-57370; Mn: 18-1102; Ni: 2.8-57.3; Pb: 2.4-66.7; Zn: 97.6-1872.2 (μg g-1dry weight). Total zooplankton abundance also showed a significant temporal variation and the most important taxa were the copepods Acartia tonsa,Eurytemora americana, the barnacle Balanus spp. (in the nauplius larval stage) and the crab Cyrtograpsus altimanus(in the zoea larval stage).In zooplankton, all the metals were detected throughout the whole sampling year and at all sampling sites, which suggests the presence of continuous or quasi-continuous sources of these contaminants. Thus, the mostabundant zooplankton species could be considered as potential biomonitors for trace metals in heavily impacted marine environments like estuaries.