Table 2.

Different factors responsible for the advanced bioremediation of dyes.

S. No.	Factors	Advanced Oxidation Processes	Biological Treatment	Phytoremediation	Nanotechnology	Biotechnological Approaches
1.	Mechanism	Utilizes chemical oxidation to break down dyes and contaminants through highly reactive species (e.g., hydroxyl radicals).	Microorganisms, enzymes, and natural processes degrade dyes biologically.	Involves the use of plants to uptake, metabolize, or sequester dyes from the environment.	Utilizes nanomaterials or nanoparticles to adsorb, degrade, or facilitate the removal of dyes.	Relies on genetically modified or engineered microorganisms for enhanced dye degradation.
2.	Speed of Treatment	Generally rapid and efficient in dye degradation.	Biodegradation rates can vary and may be slower than chemical oxidation.	Treatment rates can be relatively slow, influenced by plant growth and environmental conditions.	Offers fast and efficient removal through high surface area and reactivity.	Can be engineered for rapid and targeted dye degradation.
3.	Selectivity	May not exhibit high selectivity and can degrade a wide range of dyes.	Microbes may exhibit selectivity towards specific dyes, affecting treatment effectiveness.	Plant species selection influences specificity, with variations in the range of dyes targeted.	Can be designed for selectivity through nanomaterial selection and modification.	Selectivity can be engineered by designing microorganisms with specific dye-degrading enzymes.
4.	Environmental Impact	May generate secondary byproducts and require careful management.	Generally environmentally friendly, with lower chemical use and reduced environmental impact.	Environmentally friendly, as it relies on natural processes and plant uptake.	Impact depends on nanomaterials used, with potential environmental concerns.	Environmental impact may vary depending on genetic modifications, but aims for minimal harm.
5.	Energy Requirements	Requires energy for chemical processes, potentially energy-intensive.	Typically energy-efficient, relying on microbial metabolism or natural processes.	Minimal energy requirements, as it mainly depends on plant growth.	Energy-efficient, but energy may be required for nanoparticle synthesis.	Energy-efficient, but genetic engineering may involve energy-intensive processes.
6.	Scale-Up Complexity	Scaling up AOPs can be complex and may require advanced infrastructure.	Scaling biological treatment systems is generally feasible but can be size-dependent.	Scalability can be challenging for large-scale phytoremediation projects due to space and time requirements.	Nanotechnology can be scaled up relatively easily but requires careful engineering.	Scalability depends on the cultivation and maintenance of engineered microorganisms, which can be challenging.
7.	Cost Effectiveness	Initial setup costs can be high due to equipment and chemical requirements.	Generally cost-effective in the long run due to lower operating costs and sustainability.	Cost-effectiveness depends on factors like plant species, maintenance, and project size.	Costs may vary depending on the nanomaterials used and their availability.	Costs can be higher due to research and development, genetic modification, and monitoring.
8.	Regulatory Considerations	May face regulatory scrutiny due to chemical usage and potential byproduct generation.	Typically meets regulatory compliance easily, especially for non-genetically modified organisms.	Regulatory approval depends on plant species used and potential ecological impacts.	Regulatory concerns related to nanoparticle release and toxicity may apply.	Requires regulatory approval for genetically modified organisms and potential ecological impacts.

Source: [176,177,178,179].