Environmental toxicity assessment in the Paraná river delta (Argentina): simultaneous evaluation of selected pollutants and mortality rates of Corbicula fluminea (Bivalvia) early juveniles

• Published in: Environmental pollution (1987) Vol. 112; no. 3; pp. 379 - 389
• Main Authors: Cataldo, D., Colombo, J.C., Boltovskoy, D., Bilos, C., Landoni, P.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.2001; Elsevier
• Subjects: Animal, plant and microbial ecology; Animals; Applied ecology; Argentina; Argentina, Parana R; Biological and medical sciences; Bivalvia - growth & development; Contaminants; Corbicula fluminea; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on protozoa and invertebrates; Fresh Water - chemistry; Fundamental and applied biological sciences. Psychology; Geologic Sediments - chemistry; Hydrocarbons - analysis; Hydrocarbons - toxicity; Hydrocarbons, Chlorinated - analysis; Hydrocarbons, Chlorinated - toxicity; Metals, Heavy - analysis; Metals, Heavy - toxicity; Molluscs; Paraná river; Pesticides - analysis; Soil Pollutants - analysis; Toxicity; Water Pollutants, Chemical - analysis; South America; Argentina; America; Argentina, Reconquista R; Argentina, Lujan R; Corbicula fluminea; Molluscs; Paraná river; Toxicity; Contaminants; Benthic organism; Hydrocarbon; Aliphatic compound; Mortality; Pesticides; Polycyclic aromatic compound; Polychlorobiphenyl; Young animal; Heavy metal; Freshwater environment; Pollutant; Bivalvia; Organochlorine compounds; Chlorocarbon; Water pollution; Stream; Invertebrata; Mollusca
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/S0269-7491(00)00145-7

Mortality rates of juveniles of Corbicula fluminea toxicity corresponded well with sediment pollutant levels in a river delta of Argentina. Water and sediment samples were collected in the lower Paraná delta at four sites with different levels of exposure to pollution to evaluate the anthropogenic impact through chemical analyses and mortality bioassays. Individual polychlorinated biphenyls, chlorinated pesticides, aliphatic hydrocarbons, polycyclic aromatic hydrocarbons, and heavy metals were measured in waters, porewaters and sediments. The same three phases were also subjected to toxicity assays with straight-hinged juveniles of Corbicula fluminea. Concentrations of several pollutants were above levels recommended for the protection of aquatic life: in waters, Zn, Cu and Cr were 1.6–4.9 times higher, whereas in the sediments Cr was 1.8–3.6, and benzo(a)pyrene was 2.8–5.6 times higher. Pollutant concentrations followed a clear geographic pattern with highest values in the densely populated area of the Reconquista and Luján rivers, lower levels in the San Antonio, and lowest loadings in the remote Paraná de las Palmas. This gradient was adequately matched by the pattern of mortality rates of C. fluminea early juveniles, which were highest in the Reconquista-Luján (40–93%) and lowest (and not significantly different from the control) in the Paraná (3.3–23%). Mortality rates also increased from surface waters (3.3–53%), to porewaters (12–73%), to sediments (23–93%). Although toxicity was probably mainly due to dissolved contaminants, agreement between chemical and biological evidence of pollution was best for the sediment compartment, whereas porewater and surface water showed a higher degree of variability.