Arifin Sandhi

Our study found that sediment heavy metal content is the primary factor influencing heavy metal uptake by emergent macrophyte species. This research aimed to quantify the concentrations of heavy metals and metalloids (As, Cd, Cu, Pb, Si, and Zn) in emergent macrophytes— Lysimachia thyrsiflora, Sagittaria sagittifolia, Phragmites australis, Glyceria fluitans, Carex nigra, Equisetum fluviatile, and Juncus effusus —as well as in the corresponding water and sediment samples from Orrefors, Läen, and Emmaboda, to assess their net accumulation and translocation capacity for application in phytoremediation management. Our results revealed that the sediment As concentration at the Emmaboda site was 23 times higher than the Swedish Environmental Protection Agency (Swe EPA) guideline value. At the Orrefors and Läen sites, the concentrations of heavy metals and the metalloid in water followed the descending order: Zn > Pb > Cu > As > Cd. Among the studied species, L. thyrsiflora was the most abundant across locations and exhibited the highest As accumulation (1,603 mg/kg) in its roots, with minimal translocation to its shoots. Si and Zn showed relatively high translocation to the shoots in most of the surveyed emergent macrophytes, regardless of location. This preliminary study indicates the substantial heavy metal accumulation in L. thyrsiflora and J. effusus . In combination with their limited translocation to the shoots, this underscores their strong potential for phytoremediation-based management of contaminated glasswork sites.

The legacy of post-industrial contamination often limits the safe use of urban soils for food production without pre-treatment to reduce metal(loid) solubility and uptake in crops. In this study, a seed residue biochar was applied at two doses (1% and 5%) to six circumneutral urban allotment soils from Denmark and the UK, all exhibiting elevated concentrations of As, Cd, Pb and Zn. Soil pore water was sampled to assess metal(loid) solubility and soil:solution partitioning, and lettuce was grown to determine metal(loid) uptake. Biochar application had varying effects on metal(loid) solubility. For As and Pb, solubility generally increased, particularly at the higher dose. For Zn and Cd, solubility tended to decline. Metal(loid) uptake in lettuce also varied, with no consistent change between control and treatments for As and Pb, despite their increased solubility. However, a clear reduction in Zn and Cd uptake was observed, especially at the 5% application rate. For Cd, this resulted in a marked decrease in the proportion of samples exceeding health-based guideline values, indicating a tangible reduction in dietary risk. These findings show that even in circumneutral soils, biochar can significantly influence metal(loid) behaviour, with the greatest benefit observed for reducing Cd accumulation in edible crops. However, the observed increase in As and Pb solubility underscores the importance of considering potential risks associated with leaching and water contamination.

Plants are composed of complex organisms that include morphological, physiological and biochemical segments. A number of environmental factors such as, heavy metals, drought, salinity, heat, and cold cause stress towards plants and impact on their growth and yield values. Heavy metal contamination and drought are considered to be two significant environmental (abiotic) factors that are receiving increased attention due their effects on plants. Many plant species from previously non-drought prone areas now face drought as a new stress factor and must develop their avoidance mechanisms. Comparing drought-related tolerance strategies, plants have developed a number of strategies to fight against heavy metal pollution due to its wide coverage. These heavy metal tolerance strategies include detoxification, compartmentalization, and storage in cell vacuoles in plants. Few similarities have been found in the mechanisms of both drought and heavy metal strategies. The use of beneficial microbes is considered as one of the most promising methods to improve stress tolerance because plant-associated microbes decrease metal accumulation while enhancing nutrient supply and water under such stress. In this review, we summarize how drought and heavy metals contamination effect on plant growth, with particular focus on stress avoidance and tolerance mechanisms, as well as, the role of microbes to enhance stress tolerance. Recommendations including irrigation, fertilization and molecular techniques to increase the plant’s tolerance mechanisms against heavy metal and drought conditions are also discussed.

The presence of high levels of carcinogenic metalloid arsenic (As) in the groundwater system of Bangladesh has been considered as one of the major environmental disasters in this region. Many parts of Bangladesh have extensively reported the presence of high levels of arsenic in the groundwater due to both geological and anthropogenic activities. In this paper, we reviewed the available literature and scientific information regarding arsenic pollution in Bangladesh, including arsenic chemistry and occurrences. Along with using As-rich groundwater as a drinking-water source, the agricultural activities and especially irrigation have greatly depended on the groundwater resources in this region due to high water demands for ensuring food security. A number of investigations in Bangladesh have shown that high arsenic content in both soil and groundwater may result in high levels of arsenic accumulation in different plants, including cereals and vegetables. This review provides information regarding arsenic accumulation in major rice varieties, soil-groundwater-rice arsenic interaction, and past arsenic policies and plans, as well as previously implemented arsenic mitigation options for both drinking and irrigation water systems in Bangladesh. In conclusion, this review highlights the importance and necessity for more in-depth studies as well as more effective arsenic mitigation action plans to reduce arsenic incorporation in the food chain of Bangladesh.