Removal of Cypermethrin from Water by Using Fucus Spiralis Marine Alga.

Violeta Năstuneac,Florentina-Daniela Munteanu,Mirela Panainte-Lehăduș,Emilian Florin Moșneguțu,Gabriela Cioca,Simona Gavrilaș

doi:10.3390/ijerph16193663

Abstract

Alpha-cypermethrin is a synthetic pyrethroid that was extensively used for insect control, since the early 1980s. However, it is known that its presence in the environment has toxic effects on humans and aquatic life forms. For this reason, it is commendable for it to be removed completely from the contaminated environment. In this study, we evaluated the adsorption capacity of a marine alga for the removal of cypermethrin from water. The adsorption experiments were performed based on the batch equilibrium technique. The samples containing the pesticide were analyzed using gas chromatography with an electron capture detector, after liquid-liquid extraction in hexane. The results obtained from the kinetic adsorption studies showed that the equilibrium time was attained after 40 min. The adsorption parameters at equilibrium concentrations, obtained through the Langmuir, Freundlich, and Temkin models, showed that the used brown marine alga has a maximum amount of adsorbed cypermethrin of 588.24 µg/g. The correlation coefficients obtained for each model prove that the Langmuir model best fits the experimental data.

Highlights

Nowadays, the most used pesticides are synthetic pyrethroids, as they are more cost-effective and less toxic to the vertebrate wildlife [1] compared to other pesticides
The present paper focuses on the possibility to use a brown marine alga, Fucus spiralis, for the removal of cypermethrin from water
For the evaluation of the capability of the alga to adsorb the cypermethrin from water, a kinetic study was conducted

Summary

Introduction

The most used pesticides are synthetic pyrethroids, as they are more cost-effective and less toxic to the vertebrate wildlife [1] compared to other pesticides (organochlorines, carbamates, and organophosphates). The pyrethroids were physiochemically characterized in an extensive review [2], where it was shown that these compounds are highly non-polar molecules, which means a low water solubility, and they present a high bioaccumulation potential Another characteristic refers to their hydrolytic stability at acidic and neutral pHs, while in alkaline conditions, some pyrethroids suffer rapid degradation because of the cleavage of the ester bridge of the molecule [2]. The lipophilicity of these compounds was the subject of different-standard laboratory toxicity research to prove that once the pyrethroids enter the aquatic environment, the exposure to the water phase is diminished by the adsorption and degradation processes. The laboratory and the in-field research led to an impressive database with results on the potential effects of the synthetic pyrethroids [3,4,5]

Methods

Results

Conclusion