Environ Anal Health Toxicol.  2019 Sep;34(3):e2019010. 10.5620/eaht.e2019010.

Experimental modeling of the acute toxicity and cytogenotoxic fate of composite mixtures of chromate, copper and arsenate oxides associated with CCA preservative using Clarias gariepinus (Burchell 1822)

• Fagbenro O
• Alimba CG
• Bakare AA

• KMID: 2470822
• DOI: http://doi.org/10.5620/eaht.e2019010

Abstract

Concurrent occurrence of chromium (Cr), copper (Cu) and arsenic (As) from chromated copper arsenate (CCA) wood preservative in aquatic ecosystems demands that their joint-actions in eliciting toxic effects be assessed for adequate understanding of the health risk they may pose to biota. Clarias gariepinus was exposed to As₂O₃, CrO₃ and CuO and their composite mixtures (1:1 and 1:1:1) at various concentrations (0 - 600 mg/L) for 96-h to determine the acute toxicity using OECD (1992) protocol. C. gariepinus was then exposed to sub-lethal concentrations corresponding to 6.25, 12.5, 25.0, 50.0 and 100% of the 96-h LC50 for 7 days to assess the cytogenotoxic effects using piscine micronucleus (MN) test. The 96-h LC50 showed that the metals/metalloid demonstrated differential interactions in a concentration dependent pattern. The 96-h LC50 showed that Cr was the most toxic while Cu and As:Cu were indeterminate (Cr > Cr:Cu > As:Cr > As > As:Cr:Cu > Cu = As:Cu indeterminate). Isobologram and synergistic ratio (SR) models predicted antagonistic interaction between Cu:Cr and As:Cr and synergism between As:Cu in the causation of morbidity and mortality of C. gariepinus. Interaction factor model predicted antagonism as common interactive mechanism among the metal/metalloid mixtures in the induction of MN and abnormal nuclear erythrocytes in C. gariepinus. Predicted interactions among the three metals/ metalloid were largely antagonism and synergism towards the induction of acute toxicity and cytogenotoxicity. The models employed herein may be useful in establishing environmental safe limits for mixtures of metals/metalloids against the induction of acute toxicity and DNA damage in lower aquatic vertebrates.

Keyword

Acute toxicity; antagonistic and synergistic interactions; Clarias gariepinus; joint-action toxicity models; metal mixtures; micronucleus test

MeSH Terms

Arsenic
Biota
Chromium
Copper*
DNA Damage
Ecosystem
Erythrocytes
Micronucleus Tests
Models, Theoretical*
Mortality
Organisation for Economic Co-Operation and Development
Oxides*
Vertebrates
Wood
Arsenic
Chromium
Copper
Oxides