Photodegradation of α-cypermethrin in soil in the presence of trace metals (Cu²⁺, Cd²⁺, Fe²⁺and Zn²⁺)

Abstract

The influence of trace metals (Cu(2+), Zn(2+), Cd(2+) and Fe(2+)) on the photodegradation of α-cypermethrin (α-CYM) in agricultural soil was studied. The soil samples were spiked with α-cypermethrin with/without the presence of metal ions, irradiated under a UV irradiation chamber for a regular period of time and analyzed by using HPLC. The dark control sterile and unsterile soil samples spiked with α-cypermethrin and selected trace metals were incubated for the same interval of time at 25 °C. The results obtained indicated that α-cypermethrin photodegradation followed biphasic kinetics. α-cypermethrin photodegradation half-lives (t1/2) were increased to 0.71 and. 4.5 hours from 0.64 hours respectively in the presence of elevated Zn(2+) and Cu(2+) concentrations. Fe(2+) and Cd(2+) increased the photodegradation reaction kinetics from -1.078 h(-1) to -1.175 h(-1) and -1.397 h(-1) and varied the t1/2 from 0.64 ± 1.41 to 0.59 ± 2.07 and 0.49 ± 2.01 in the soil. Microbes also affected the degradation of α-cypermethrin in metal contaminated soil. The degradation rate was inhibited in unsterile soil and was found to be in the following order: Cd(2+)< Zn(2+)< Cu(2+)< Fe(2+). The degradation/persistence of α-cypermethrin was affected linearly with the increasing soil metal concentrations.

Zn2+ and Cd2+ assisted photo-catalytic degradation of chlorpyrifos in soil

“…For example, Zn 2+ and Cu 2+ are known to reduce the dissipation of deltamethrin and cypermethrin in the soil but Fe promotes their dissipation rate (Yang et al., 2010) . Similarly, our previous studies have also reported the degradation of CLP, and a number of other pesticides in the presence of some metals (Rafique et al., 2016a, Rafique and Tariq, 2015). It is important to determine the metals that have pronounced influence on the photodegradation of pesticides but have minimal hazardous effect on the environment so that a strategy may be developed for safer remediation of these pesticides from the soil.…”

“…2-a). Zinc has also been reported to enhance the photodegradation of α-cypermethrin in soil (Rafique and Tariq, 2015).…”

“…Spiked and reference unspiked soil samples were irradiated for specified time interval. Initial moisture level of soil samples were maintained during the experiment period (Rafique and Tariq, 2015).…”

“…Although few researchers has been tried to characterize these interactions but their potential cocktail effect and toxicity remains mysterious till now (Reddy et al., 2012; Chen et al., 2015). Metals affect the pesticides degradation in multiple ways either they enhance the pesticides breakdown like Fe and Cu enhanced the degradation of metribuzin, chlorpyrifos, imidacloprid (Vágvölgyi et al., 2010; Reddy et al., 2012; Rafique and Tariq, 2015), modulated its dissipation rate e.g. cobalt, Cd 2+ and manganese decreased the degradation of organophosphorus pesticide (such as fenitrothion, chlorpyrifos), Copper nanoparticles can increase the persistence of Atrazine in soil (Moon, 1990a,b, Parada et al., 2019) and unaffected the pesticides dissipation rate like nickel unaffected the degradation of metribuzin (Moon, 1990a,b) and Pb had little influences on the dissipation of high concentrations atrazine (Chen et al., 2014).…”

Facile synthesis and characterization of magnetic nanocomposite ZnO/CoFe2O4 hetero-structure for rapid photocatalytic degradation of imidacloprid

“…They not only influence the people involved in agriculture but also are carried to long distances because of their longer half-lives and entering the water bodies in the end [6, 7, 8, 9, 10]. This scenario is worsened in countries like Iran due to limited water resources and existing resources being polluted by the reckless and unnecessary use of the agrochemicals [11]. Therefore, developing a well-organized and cost-effective technology seems essential to remove these dangerous pollutants from waters and wastewaters completely.…”