Applications in environmental risk assessment of leucocyte apoptosis, necrosis and respiratory burst analysis on the European bullhead, Cottus sp

The use of a biochemical multi-biomarker approach proved insufficient to obtain clear information about ecosystem health. The fish immune system is considered as an attractive non-specific marker for environmental biomonitoring which has direct implications in individual fitness and population growth. Thus, the present work proposes the use of fish immunomarkers together with more common biochemical biomarkers in sampling conditions optimized to reduce biomarker variability and increase parameter robustness. European bullheads (Cottus sp.) from 11 stations in the Artois-Picardie watershed (France) were sampled. In the multiple discriminant analysis, the sites were highly correlated with apoptosis, respiratory burst, GST and EROD activities. Moreover, the use together of biochemical and immune markers increased the percentage of fish correctly classed at each site and enhanced site separation. This study argues in favor of the utilization of apoptosis, necrosis and respiratory burst for the determination of environmental risk assessment in addition to the set of biochemical biomarkers commonly used in fish. •Optimization of biomarker variability and parameters robustness for biomonitoring.•Adding of fish immunomarkers together with more current biochemical biomarkers.•Use of immune system allows a better evaluation of fish health.•We argue for the deployment of immunomarkers in freshwater monitoring programs. Attractive use of freshwater fish leucocyte non-specific immune function in environmental risk assessment according to international recommendations.