Remediation of Soils Contaminated by Pesticides Using Physicochemical Processes: a Brief Review

Abstract

After years of pesticide application, often indiscriminately, damage has been caused to the environment, as well as to agronomic crops grown in contaminated areas. In water treatment, techniques based on physical and/or physicochemical processes are used, being formed secondary oxidizing agents responsible for the mineralization of contaminants present in the herbicides, thus causing the degradation process. However, few studies have demonstrated the effectiveness of these techniques in soils. The aim of this study was to review the existing studies, presenting the main techniques used for remediation of soils contaminated with pesticides. Emphasis was placed on electrokinetics, advanced oxidative processes, soil washing, chemical or solvent extraction, and combinations of these methods. According to the results of several studies, the combination of techniques, such as electrokinetics and soil washing processes, allows achieving a high efficiency when it is applied for the degradation of agricultural contaminants. The combination of electrolysis with other methods, such as the Fenton’s reagent, ultrasound irradiation, and UV light, also present satisfactory results in removing pesticides in soil treatment. However, Fenton technology used alone is the most promising of the assessed techniques since it can be used for the remediation of several contaminants, especially pesticides, not harming the environment and allowing soil recovery.

Insights into the recent advances in nano-bioremediation of pesticides from the contaminated soil

“…The soil has its capacity for degradation of compounds used in the pesticides up to a certain extent but a high concentration of these compounds is toxic for the soil microflora involved in the bioremediation and therefore needs necessary interventions in this area ( Cheng et al, 2016a ). Several techniques based on physical, chemical and physicochemical principles have been used for the bioremediation of the soil ( Baldissarelli et al, 2019 ).…”

“…For the degradation of chlorinated pesticides like DDT (Dichlorodiphenyltrichloroethane), Fenton’s method was used in combination with other oxidative systems like zero valence ion, Ethylene diamine tetraacetic acid, air (ZVI/EDTA/Air; Cao et al, 2013 ) with the amino ZVI/Air system ( Zhou et al, 2014 ) and with trisodium citrate ( Vicente et al, 2012 ). Though the variety and efficiency of Fenton’s reaction to degrade contaminants and pollutant have shown promising potential but the studies using this technique for mass soil contaminants treatment is still the same ( Baldissarelli et al, 2019 ).…”

“…It is environmentally friendly and requires a shorter treatment time. It can be operated easily with low operation costs ( Baldissarelli et al, 2019 ). But even Fenton oxidation suffers from a few limitations as it causes a reduction in soil pH, oxidizes harmless organic material of the soil and immobilization Fenton technique of inorganic reactive species on the treatment wall ( Cheng et al, 2016a ).…”

Phytoremediation and Bioremediation of Pesticide-Contaminated Soil

“…The remediation of pesticides in soil and ground water is important because of public health, the need for healthy productive soils, and for drinking water that is safe to consume. There are several reviews of research on the remediation processes for pesticide contaminated soil [4,13,21,34,40,78,111,114,122,147,163,192,200,214,219,222,223,228,236,262,[274][275][276][277][278][279][280][281]283,284]. The review on physicochemical remediation processes [275] is a very recent addition to the literature, and the review on bioaugmentation [277] was published in 2017.…”

“…Cycon et al [277] have a table of physico-chemical properties of selected pesticides and a table of characteristics of the degradative potential of pesticide-degrading microorganisms for selected pesticides. Remediation using Fenton reagent has been identified as an effective physicochemical process by Baldissarelli et al [275]. Rodrigo et al [278] have provided a very good review on electrochemically assisted remediation of pesticides.…”