Synergistic degradation of Chlorpyrifos by modified solar Photo-Fenton process with bacterial metabolism reduces in vivo biotoxicity in zebrafish (Danio rerio)

The extensive use of Chlorpyrifos (CP) as insecticide has raised concern to their hazardous impact on human health and ecosystems. Bioremediation has been proved as one of the key eco-compatible method for reducing these environmental toxicants. This study explores and evaluate the effectiveness of a combined process including solar Photo-Fenton process followed by bacterial degradation using Ochrobactrum sp. CPD-03 for effective CP degradation in wastewater. Moreover, the in vivo molecular biotoxicity of CP and degraded CP has been evaluated with embryonic zebrafish. The solar Photo-Fenton treatment showed CP degradation efficiency of ∼42 % in 4 h and ∼92 % in 96 h with combined bacterial degradation process. In vivo biotoxicity analysis showed increased survivability of embryonic zebrafish exposed to CP with CPD-03 in water with lesser morphological abnormalities. The mechanistic molecular analysis showed decreased acetylcholinesterase inhibition and GST activity in embryos exposed to CP with CPD-03 for a lesser apoptosis due to influential intrinsic interaction with metabolic proteins. The study advocated to the use of solar Photo-Fenton process followed by bacterial degradation for an efficient ecological degradation of CP for effective reduction of in vivo biotoxicity.