Inhibition of two enzyme systems in Euchlanis dilatata (Rotifera: Monogononta) as biomarker of effect of metals and pesticides

Abstract

The inhibitory effects on esterases and phospholipase A2 (PLA2) in the freshwater rotifer Euchlanis dilatata, native to Mexico, were assessed by fluorimetry after in vivo exposure (30 min) in laboratory conditions to sublethal concentrations of metals and pesticides. EC₅₀ values for esterases ranged from 7.9 × 10⁻⁷ for DDT to 61.9 μg l⁻¹ for methyl parathion, while corresponding values for PLA2 ranged from 0.96 × 10⁻⁶ for mercury to 69.2 μg l⁻¹ for lead. These enzyme systems in E. dilatata are very sensitive to the tested agents and suggest they would be suitable biomarkers. However, sensitivity to other environmental contaminants should be investigated in laboratory conditions and field studies to assess their potential as environmental biomarkers.

Keywords::

• Aquatic toxicology
• esterases
• phospholipase A2
• in vivo biomarker
• rotifers

Acknowledgements

The authors wish to thank the National Council for Science and Technology of Mexico for providing a scholarship (271723) to J.C.A.-A. The authors thank Marta Pérez-Reyes for her collaboration in the laboratory.

Declaration of interest

The authors report no declarations of interest.