Abstract
Chlorpyrifos is an organophosphorus insecticide, acaricide and miticide used worldwide for the control of soil-borne insect pests. It must be considered as a substance of growing concern, given its use, toxicity, environmental occurrence, and potential for regional to long-range atmospheric transport. Considering the incomplete removal attained by conventional water treatment processes, we investigated the efficiency of electrolytic radicals production and sonoelectrolysis on the degradation of the pesticide. The treatment has been conducted in a novel electrochemical reactor, equipped with a boron-doped diamond anode and a solid polymer electrolyte (SPE). Different current intensity and times have been tested and coupled with sonication at 40 kHz. Up to 69% of chlorpyrifos was completely removed in 10 min by electrolysis operated at 0.1 mA, while 12.5% and 5.4% was converted into the treatment intermediates 3,5,6-trichloro-2-pyridinol (TCP) and diethyl (3,5,6-trichloropyridin-2-yl) phosphate, respectively. Ultrasound irradiation did not enhance the removal efficiency, likely due to mass transport limitations, while the energy consumption increased from 8.68∙10− 6 to 9.34∙10− 4 kWh µg− 1 removed. Further research is encouraged, given the promising processing by the SPE technology of low conductivity solutions, as pharmaceuticals streams, as well as the potential for water and in-situ groundwater remediation from different emerging pollutants as phytosanitary and personal care products.
Highlights
Chlorpyrifos (CP) is an organophosphorus insecticide, acaricide and miticide effective against a broad spectrum of insect pests
Helium was chosen as carrier gas (1.96 mL min− 1), injection was made in splitless mode, sampling time and purge flow were set at 1 min and 3 mL min− 1, respectively
This study demonstrated that chlorpyrifos can be effectively removed from water by anodic oxidation and ultrasonic irradiation, even at concentration < 0.1 mg L− 1
Summary
Chlorpyrifos (CP) is an organophosphorus insecticide, acaricide and miticide effective against a broad spectrum of insect pests. The inhibition of the enzyme acetylcholinesterase in the central and peripheral nervous systems leads to the breakdown of the neurotransmitter acetylcholine, overstimulating muscarinic and nicotinic receptors (Zhao et al 2006). The lethal times LT50 and LT90 for orally treated Apis mellifera workers were calculated as 171.1 and 3.2 h, 839.7 and 11.7 h at 0.001 and 100 ppm, respectively. The lethal concentrations on honeybee workers LC50 and LC90 ranged from 170.6 to 0.01 ppm and from 2855.2 to 1.4 ppm after 3 and 120 h of treatment, respectively. CP application in cotton fields resulted in the death of 39.7% of the bee workers, and in a significant decrease of bee foraging activities
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
