Genotoxicity in fishes environmentally exposed to As, Se, Hg, Pb, Cr and toxaphene in the lower Colorado River basin, at Mexicali valley, Baja California, México

• Published in: Ecotoxicology (London) Vol. 29; no. 4; pp. 493 - 502
• Main Authors: Flores-Galván, M. A., Daesslé, L. W., Arellano-García, E., Torres-Bugarín, O., Macías-Zamora, J. V., Ruiz-Campos, G.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-05-2020; Springer; Springer Nature B.V
• Subjects: Ameiurus natalis; Animals; Arsenic; Congeners; Correlation analysis; Cyprinus carpio; Drains; Earth and Environmental Science; Ecology; Ecotoxicology; Environment; Environmental Management; Environmental Monitoring; Erythrocytes; Fish; Fishes; Fishes - physiology; Fresh water; Freshwater fish; Freshwater fishes; Genotoxicity; Inland water environment; Insecticides; Lagoons; Lead; Mercury; Mercury (metal); Metals - metabolism; Metals - toxicity; Mexico; Muscles; Pollutants; Return flow; River basins; Rivers; Selenium; Tilapia; Tilapia zillii; Tissue; Toxaphene; Toxaphene - metabolism; Toxaphene - toxicity; Valleys; Water Pollutants, Chemical - metabolism; Water Pollutants, Chemical - toxicity; Mexico; Colorado River; Baja California Mexico; Water; Fish; Pollution; Micronuclei; Erythrocytes; Mexicali
• ISSN: 0963-9292; 1573-3017
• DOI: 10.1007/s10646-020-02200-9

The environmental exposure to As, Se, Hg, Pb, Cr and toxaphene was assessed for 11 freshwater fish species in irrigation channels, agricultural return flow drains, a drain collecting lagoon and sections of the Colorado River at the Mexicali valley in Baja California, México, during August 2015–April 2016. Arsenic (2.90 ng ml
−1
) and Se (1.41 ng ml
−1
) in water had the highest concentrations in the return flow drains (Hardy River and Xochimilco Lagoon, respectively). However, fish axial muscle tissue had the highest concentration of Se (8.3 µg g
−1
) and Hg (0.36 µg g
−1
) in Colorado River fresh water, while As (1.7 µg g
−1
) in Hardy River fish was highest. Selenium concentrations in all fishes and toxaphene in
Cyprinus carpio
and
Ameiurus natalis
are above the safe levels for human consumption (0.3 µg g
−1
and 180 ng g
−1
respectively). Toxaphene was detected in the fish axial tissue, having the highest concentrations in
Poecilia latipinna
(690 ng g
−1
) in the Colorado River. The low proportion of the 8-Cl toxaphene congeners in fish suggests degradation of this pollutant.
Tilapia
. sp. cf.
zillii
had the most genotoxic damage with 7.4 micronucleated erythrocytes per 10,000 erythrocytes in Xochimilco Lagoon and 2 in Hardy River. The genotoxicity in all the fish species studied was significantly correlated to the concentrations of As and Se in water.