Fluoride often exists in nature in the form of F\({}^{-}\) and forms soluble salts with monovalent alkali metals in groundwater, such as fluoride salt (NaF) and fluoride potassium salt (KF) [3]. Meanwhile, fluorite (CaF\({}_{2}\)), sellaite (MgF\({}_{2}\)), and fluoride-bearing silicate minerals such as mica, amphibole, touralmine, and fluorapatite are commonly found in soils or rocks. Therefore, the weathering of fluoride minerals could be a natural source of fluoride in water [3]. In the groundwater systems, I commonly exists in the form of iodide (I\({}^{-}\)),iodate (IO\({}_{3}\)\({}^{-}\)), and organic iodine (OI), and I\({}^{-}\) is the dominant species in groundwater, whereas IO\({}_{3}\)\({}^{-}\) and OI are the common species in the soil/sediments [29]. Organic contaminants include a range of conventional pollutants such as petroleum hydrocarbon, phenolic compounds, and pesticides, while concerns have also extended to persistent organic pollutants, such as perfluoroalkyl and polyfluoroalkyl substances (PFAS), pharmaceuticals and personal care products (PPCPs), antibiotics, and microplastics [2; 5; 8]). Perfluorinated compounds (PFCs) including PFAS are persistent organic pollutants that can linger in soil and impact groundwater long after their use [40]. They are highly toxic and include chemicals such as PFOA and PFOS. The antibiotic pollution in soils and groundwater is diverse, with substances such as ciprofloxacin and sulfamethoxazole found in high concentrations [8; 20]. Microplastics include small plastic particles including polyethylene and polyvinyl chloride, etc., resulting from the breakdown of larger plastic waste [41; 42]. Pollutants in soil and groundwater pose significant risks to both ecosystems and human health [39; 43]. These pollutants enter the human body through pathways including bioaccumulation, the food chain, and drinking water, leading to different types of toxicity, including chemical toxicity, radiation toxicity, and carcinogenicity. Common pollutants, such as nitrogen, when present in excess, can cause various cancers and other health issues [21]. Heavy metals, such as arsenic, chromium, and lead, can lead to cancer, organ damage, and nervous system disorders [29; 36]. Radioactive isotopes in groundwater can be highly toxic, affecting various bodily systems. Additionally, non-degradable organic pollutants, such as antibiotics and microplastics, pose emerging health risks due to their persistence and limited microbial degradation [20; 42]. The transformation of contaminants within soil-groundwater ecosystems can lead to either an exacerbation or attenuation of their effects. The processes of degradation, redox reactions, and other chemical transformations can significantly impact the persistence and fate of pollutants. An in-depth exploration of these mechanisms together is vital to developing sustainable solutions for remediating contaminated sites. The range of strategies for alleviating the impact of contaminants in soil-groundwater systems includes the monitoring and assessment of pollutant levels, the implementation of containment measures, the promotion of natural attenuation through bioremediation, the incorporation of remediation materials, and the employment of engineered solutions such as permeable reactive barriers or pump-and-treat systems to capture and treat contaminated groundwater, as well as phytoremediation to treat contaminants before they seep into aquifers ([44; 45; 46; 47; 48; 49]). Before these techniques are used, their cost and resulting environmental impacts should be considered. Bioremediation emerges as a particularly promising, sustainable, environmentally friendly, and cost-effective strategy. To start with, understanding the assembly of microbial communities, their driving forces (e.g., their pH, salinity, nutrients, and metals) and their role in transforming pollutants in the vadose-zone-groundwater ecosystem is instrumental to unlocking the full potential of bioremediation [50; 51; 22; 52].