Environmental pollution has become and increasing concern due to growing risk to human health. Soil pollution is an aspect of environmental pollution that has received comparatively less attention than water pollution. However, considering direct effects of contaminants transmission through ingestion to the human body, it can lead to greater risks for human health. Arsenic is a highly prevalent environmental pollutant, and considerable number of people worldwide suffer from constant exposure to it. While there are several ways to manage and remediate contaminated soils, phytoremediation has been paid special attention due to its higher social acceptability and lower cost. Nevertheless, this approach faces challenges, including effectively handling significant quantities of contaminated biomass, managing it appropriately, and selecting suitable plant species for the remediation process. In this regard, numerous endeavors have been undertaken to tackle these obstacles like strategies encompass the utilization of amendments, adept management of biomass, and the implementation of hybrid remediation approaches. This study aims to review prior research on mechanisms, challenges, and enhanced phytoremediation of arsenic-contaminated soils, encompassing reduction of contaminated biomass after phytoremediation.

In order to assess the environmental impact of soil polluted with trace metals, representative soils were collected surrounding the abandoned Pb–Zn mine mill (SM soils), and the new temporary ore storage site (SS soils), which are located in the vicinity of Medina (Aures), North-east of Algeria. Total digestion has been used to determine the total content of Zinc, Copper, Lead, Cadmium, and Arsenic, then it was analysed by inductively coupled plasma atomic emission spectrometry (ICP-AES). The sequential extraction Tessier scheme was also used to extract the chemical forms of Zn, Cu, and Pb, and their concentrations in each fraction were analyzed by atomic absorption spectrometry. Lead was the most abundant trace metals, its concentration in mg.kg-1 ranged between (67.20 – 46000), followed by Zinc (26 - 1853), Copper (32 – 495), Arsenic (8 – 116), and Cadmium (0.3 - 7.30). Sequential extraction shows that Zinc was mainly associated with reducible and residual fractions. Copper was bound predominantly with the minerals in the residual fraction, followed by the organic matter. Lead was bound mainly with carbonate fraction in SM soils, while Pb in the SM soils was mainly associated with the reducible fraction. The Pb, Zn, Cu mobility factor was significantly higher in SM soils than in SS soils. These results indicate that anthropic activities related to ore concentration and mining process lead to increased concentration of trace metals in surrounding soils, hence their mobility and bioavailability, this consists a potential risk to the environment and biota.

The present study aims at investigating the feasibility of using solar energy as a power source to run electro-kinetic remediation in order to clean-up lead from three types of Iraqi soil. In order to do so, it carries out six tests with enhancement conditions, involving pH control and injection wells. Conducted in the city of Baghdad, Iraq, the experiment, is divided into two groups so that the effect of applying continuous and constant voltage from solar panels study, by means of charge control and battery along with non-continuous and non-constant DC voltage from solar panel could be studied. The DC voltage has been generated by two Solar panels, each with a maximum voltage of 17 volts. All experiments have commenced in March 2017, wherein the soil has been contaminated with a concentration of Pb, equal to 1500 mg/kg as well as initial moisture content equal to 30%. The remediation lasts for seven days, with a potential gradient of about 1.2 V/cm. At the end, the experimental results show that the overall removal efficiencies of 90.7%, 63.3%, and 42.8% have been achieved for sandy, sandy loam, and silty loam soils, respectively, when using solar panels with charge control and battery.