Aquatic Ecotoxicology: From the Ecosystem to the Cellular and Molecular Levels

Abstract

This review of aquatic ecotoxicology is presented in three parts. First, we discuss the fundamental concepts and stress the importance of its ecological basis and the complexity and diversity of the field of investigation, which result from actions and interactions between the physicochemical characteristics of the biotopes, the structural and functional properties of the living organisms, and the contamination modalities. Ecotoxicological mechanisms, regardless of the level of biological complexity, primarily depend on the bioavailability of the toxic products. Numerous processes control the chemical fate of contaminants in the water column and/or sediment compartments; accessibility to the biological barriers that separate the organisms from their surrounding medium depends directly on bioavailability. Second, we review the principal methodologies of the field, from in situ studies at the ecosystem/ecocomplex level to bioassays or single-species tests. Third, we focus on mercury, selected as a reference contaminant, in order to illustrate the main ecotoxicological concepts, the complementarity between field and laboratory studies, and the indispensable multidisciplinarity of the approaches. Environ Health Perspect 105(Suppl 1): 21-35 (1997)

Acute intraperitoneal mercury chloride contamination and distribution in liver, muscle and gill of a neotropical fish Hoplias malabaricus (BLOCK, 1794)

“…This observation was relevant, since the fish tissue consumed by humans was the muscle tissue and "Tilapia" showed resistance to the absorption of mercury in the muscle, even when exposed to high concentrations of that element, a conclusion similar to the one reached in the present study. The distribution of mercury in the fish tissues results in the actions and interactions between the factors such as the exposure condition (importance of the entrance path via water/diet or intraperitoneal injection) and the chemical forms of the metal (inorganic mercury Hg(II)/MMHg) (Boudou and Ribeyre, 1997;Jackson, 1998;Wiener et al, 2003;Régine et al, 2006). Thus, the intraperitoneal administration path of the HgCl 2 contributed to the high total concentrations of Hg observed in the liver and gill of the fish.…”

Heavy metal accumulation of Danube river aquatic plants — indication of chemical contamination

“…Increased concentrations of heavy metals in aquatic environments does not lead to visible plant damage as plants have developed specific physiological mechanisms to survive in these polluted conditions [13,20]. The ability to effectively remove metal ions out of solution and to accumulate high levels of these pollutants in plant tissue are dependent on plant species and metal ions.…”

Acute toxicity test of detergent powder in silver carp (Hypophthalmicthys molitrix), common carp (Cyprinus carpio), goldfish (Carassius auratus) and roach (Rutilus rutilus caspicus)

“…The second assumption is that the specified one is the minimum LC50 that kills the fish during the associated exposure interval. Fortunately, most reliable LC50 satisfies these two assumptions (Boudou & Ribeyre 1997 …”