Environmental cadmium and lead concentrations in the Bahía Blanca Estuary (Argentina). Potential toxic effects of Cd and Pb on crab larvae

Oceanologia

关键词: Atmospheric electricity;    Air ions;    Gas bubbles;    Baltic Sea;   

DOI  :  

来源: DOAJ

【 摘 要 】

The Bahía Blanca Estuary includes a large tidal plain with an areaclose to 1150 km². Mud is predominant in its sediments, where asignificant population of the crab Chasmagnathus granulata livesduring the whole year. Moreover, there are important urban and industrialdischarges into this environment.Cd and Pb concentrations were determined in samples of water(for both dissolved and suspended particulate matter) and surfacesediments (total and 63 µm fractions). Organic matter wasanalysed in the sediments, while temperature, salinity, pH anddissolved oxygen were measured in the estuarine water. The metal concentrations determined in this study were:1.47 ± 1.08 µg Cd g^–1 and 14.68 ± 4.31 µg Pb g^–1 in surface sediments;2.21 ± 1.33 µg Cd g^–1 and 25.70 ± 7.09 µg Pb g^–1in the <63 µm sediment fraction; 0.18 ± 0.11 µg Cd g^–1and below the analytical detection limit of Pb in suspendedparticulate matter. Furthermore, dissolved Cd and Pb were lowerthan the norms for marine and estuarine waters (2 µg dm^–3for Cd and 5 µg dm^–3 for Pb, E.P.A.).
Simultaneously, the effects of Cd and Pb were studied on recentlyhatched larvae of Ch. granulata, through 96-hour semi-staticacute assays. Viability was the criterion assessed in the assays.LC₅₀ (96 h) for Cd was 46.43 µg dm^–3(36.92 - 56.34 µg dm^–3, whilst that for Pb was 1.00 mg m^–3(0.79 - 1.23 mg dm^–3, which demonstrates that Cd is moretoxic towards larvae. Finally, both LC₅₀ values determinedfor Cd and Pb were higher than the corresponding metal concentrationsmeasured in the Bahía Blanca environment.

【 授权许可】

Unknown