Impacts of Waste Plastics on Soil Health: Reduction, Control, and Prevention Approaches

Plastic consumption has increased by around 180 times from 1950 to 2018, as reported in the Journal of Cleaner Materials. Plastic usage has increased in recent decades because of cheap manufacturing costs, resulting in the creation of approximately <11,000 tons of plastic in Indian states. It is risky for us to remove plastics from the entire soil because they hinder plant growth. So, it is critical to limit plastic consumption. Plastics are harmful; various types of plastics are available on the market, including PP, PVC, HDPE, LDPE, etc. On the other hand, Tritan plastics are useful because they are BPA-free.  Penskydialomospheres (good hopes in better format) are a powerful source for all of us. It is very urgent and needful for us. Properties such as high glas transition temperature and high melting temperature indicate their ability to maintain shape and strength at elevated temperatures. Currently, the conversion of this plastics form utilization to waste has becomes a worst for out environment. The generation of plastic waste in the world increased gradually due to the three main points are the ability of plastics to replace traditional materials such as ceramic, wood and glass, the easy access to consumer usage.   

One of the creative projects launched by Kachra Cafe is the conversion of garbage into useful items. Waste material provides several benefits due to its mass or density. The procedure is simple and effective. If you have a lot of rubbish, such as plastics, e-waste, or other types of waste, it can be turned into delicious meals or utilised to earn significant points. I also take it from them. Those points can also be redeemed for clothing, showcase goods, and paper-based utensils at their stores (in Bhopal).

Picture: Best out of Waste (Paper-Based Utensils) captured from Bhopal's Kachra Cafe.  

Effective management of waste plastics requires efficient collection, sorting, and recycling methods. Effective waste management infrastructure prevents plastics from polluting the soil through open dumping or landfill contamination. In agricultural fields, the regulated application and proper removal of plastic mulches are crucial to avoiding soil pollution.

Mitigation of soil pollution necessitates comprehensive, sustained strategies. Policies such as extended producer responsibility (EPR), plastic prohibitions, and soil conservation measures mitigate plastic pollution. Consistent surveillance of microplastics in soil, advancement of sustainable materials, and encouragement of circular economy practices are essential preventive strategies.

Here’s a state-wise breakdown of plastic waste generated (as collated from government statements and data summaries):

  

The management of this waste is governed by the Plastic Waste Management (PWM) Rules, which emphasize Extended Producer Responsibility (EPR).

Recyclable vs. Non-Recyclable: Approximately 60% of India's plastic waste is recycled, largely through the informal sector. The remaining 40% often ends up in landfills or as environmental litter.

Single-Use Plastics (SUP): A significant portion of the waste stream consists of SUPs, which were subject to a national ban starting July 2022 to mitigate long-term ecological damage.

Energy Recovery: Non-recyclable plastics (RIC 3, 6, and 7) are increasingly diverted to Cement Kilns for co-processing or used in road construction to improve the bitumen binder properties.

Microplastics environmental release and concern for human health 

There are numerous disadvantages of plastic consumption in daily routine. Once it's started to sell out in terms of baggage or other forms of use of plastics, it can't be recycled back to its original monomer form easily. PP is a type of plastic that currently accounts for 0.7% of the world's recycling rate. It is lower than expected compared with other plastics such as LDPE, HDPE, PP, PVC, Tritan, etc. In the presence of sunlight, plastic releases a number of microplastics (5 mm) and is unable to degrade easily except in the marine environment. These microplastics are consumed by aquatic animals and make it difficult for them to survive. Humans are extremly postering plastics for daily consumption, once it enters the market, that may disrupt the human life cycle. There are no compensation issues by government programme, which includes health issued occured by plastics, even though there are no policies. Attention is mandatory, and there is awaited research on the reduction of plastics. Still, scientists are focusing on replacing, but there are million tons of plastic waste produced annually and dumped into specific areas, where nobody can survive. 

Agricultural soils receive 0.63-1.75 million microplastic (MP) particles/hectare/day due to sewage sludge application. Aged MP have higher sorption coefficients for contamination (heavy metals), Antibiotics, BPA, phthalates. In lab scales, there are some detection methods to understand the presence of MP in soil and water by FTIR, Raman spectroscopy, and pyrolysis-GC/MS. Commonly trace elements and compounds or groups by these advanced techniques. The ubiquity of microplastics in environmental matrices and their confirmed presence in human tissues, combined with mechanistic evidence of oxidative stress, inflammation, and endocrine disruption, highlights microplastics as an emerging global health concern requiring urgent regulatory and technological intervention. 

Exploring Textile Effluent treatment Techniques to make Water drinkable

The Indian textile industry plays a vital role in the supply chain and marketing of garments and diverse handloom products, thereby strengthening India's commercial position in the global market. The exceptional performance of textiles in the regions of Gujarat, Tamil Nadu, Maharashtra, Rajasthan, Madhya Pradesh, and Punjab in terms of woollen production facilities. According to the Annual Survey of Industries (ASI), 23.6% of the textile sector in Gujarat exhibits high levels of production. 

 

 

Textile industries generate a large volume of complex effluents during the processing of clothes, and before discharging, which is a high organic and inorganic effluent load on the environment. Azo, Benzo, Cationic, Xanthene, a group of dyes that are effective in our humanity and the abiotic life cycle. According to the Central Pollution Control Board (CPCB) survey, 92 million tons of effluent were generated in FY23-24. This wastewater often shows high TDS, salinity, alkalinity, and electrical conductivity, primarily originating from salt-intensive dyeing processes. Additionally, textile wastewater contains heavy metals (Cr, Cu, Ni, Zn), formaldehyde-based resins, and chlorinated compounds, posing ecotoxicological and human health risks. Some of the most carcinogenic groups of dyes are the reactive dyes, which are harmful and highly soluble in water molecules, for example, RB21 (Reactive Turquoise Blue 21) dye. The general molecule's formula is C₄₀H₂₅CuN₉O₁₄S₅, represents a copper phthalocyanine reactive dye with multiple functional groups (nitrogen heterocycles, sulfonic groups) around a central Cu atom. Typically contains reactive vinyl sulfonyl (–SO₂–CH=CH₂) or sulfatoethylsulphonyl groups that can form covalent bonds with hydroxyl (–OH) groups of cellulose fibres during the dying process. One of the most advanced research studies was successfully published in a reputed journal, which one is the advance solutions to degrade this carcinogenic pollutant by using the AOPs (Advance Oxidation Processes) technique. 

Catalyst is the altering the rate of the reaction. One of the most susceptible, highly active, emerging, and advanced materials in the presence of visible light also enhances COD, BOD, and DO rates to make water drinkable. Recent breakthroughs to mineralise faster RB21 with the combination of materials with hybrid techniques like Photocatalyst+Ultrasonication, UV+Ozonation,  Corona Discharge Plasma with Fe2+ addition,n etc. 

    

Method	Approx. RB21 Removal	Notes
Corona plasma + Fe²⁺	~100% color removed, ~83 % COD ↓	Advanced oxidation
Photo‑ozonation	~99 %	Very short reaction times
SmFeO₃‑rGO + ultrasound	High degradation (faster)	Effective on the actual effluent
Fly ash adsorption	Moderate capacity (~105 mg g⁻¹)	Very low cost
Photocatalysis with MgFe2O4	93 %  removal rate	AOP, low cost

Figure 1: Advance Oxidation Process (AOPs) Techniques performance over RB21 dye degradation (Predictive analysis) (a) Various AOPs Utilised for RB21 dye (b) Concentration variation over RB21 with Vis. + H2O2

Figure 1 assumes a RB21 dye concentration of 25 ppm, utilising AOPs techniques, including ozonation, photocatalysis, photo-Fenton, and UV and Vis light irradiation with H₂O₂ as an oxidant to break the interaction between the dye and H₂O molecules. 

Azo bond is extremely ozone-sensitive -N=N- bond undergoes rapid cleavage, R-N=N-R + Ozone to form aromatic amines with smaller fragments. When using ozonation, one ozone molecule can break chromophoric structure, leading to rapid decolourisation, but at high concentrations of RB21,

Ozone ​+ OH− → •OH + O2​

$$•OH + \text{RB21} \rightarrow \text{fragmented intermediates}$$

$$\text{Why its happening, ozonation destroys chromophores first, and some aromatic fragments remain due to not destroyed completely, like sulfonated benzene/naphthalene derivatives. It becomes colourless but lack of degradation onto benzene rings. Why aromatic fragments are hard to remove becausethey have resonance stability and can react with ozone slowly in the presence of hydroxyl radicals. }$$

$$\text{Figure (a) compares the degradation performance of Reactive Blue 21 (RB21) dye utilizing various advanced oxidation processes (AOPs) across reaction time. All processes demonstrate a time-dependent rise in degradation efficiency, indicating continual reactive oxygen species formation. Initial degradation is modest due to negligible radical formation. UV/H₂O₂ and visible light/H₂O₂ systems outperform ozonation, photocatalysis, and photo-Fenton reactions in degradation efficiency as irradiation time increases. Superior performance of peroxide-assisted systems is due to increased photolysis of H₂O₂, resulting in numerous hydroxyl radicals (•OH) with strong non-selective oxidation capability. The photo-Fenton process degrades effectively by Fe²⁺/Fe³⁺ redox cycling under light, while photocatalysis and ozonation have reduced efficiency due to electron-hole recombination and restricted oxidant use. The study shows that light-assisted H₂O₂-based AOPs effectively degrade RB21.}$$

$$\text{Figure (b) shows how initial RB21 concentration impacts degradation efficiency during visible light/H₂O₂ treatment at various irradiation periods. Increased dye concentration decreases degradation efficiency, suggesting faster degradation kinetics at lower initial concentrations. Low dye concentrations (10–25 ppm) increase efficiency due to better light penetration and more hydroxyl radicals per dye molecule. In contrast, greater concentrations (75–100 ppm) impair efficiency due to the inner filter effect, increased solution opacity, and extra dye molecules and intermediate degradation products competing for hydroxyl radicals. However, continuous irradiation boosts deterioration at all concentrations, proving the durability of the visible light/H₂O₂ combination. These findings show that initial dye concentration controls reaction kinetics and AOP efficiency.}$$

$$  In the figure, sets for the degradation of the pollutants with various techniques for the effluent treatment. The first graph shows the results based on the different concentration 10, 20, and 30 ppm over the US (Ultrasound) in the presence of UV light, with PDS and a certain amount of catalyst dosage were estimated. That graph shows that the highest degradation range is at 10 ppm, while 30 ppm shows the results are much lower due to the increase in the concentration of effluent. Figure 1: Overall Lab Experimental setup for Hydrogen Production after wastewater treatmentWastewater treatment has emerged not only as a critical environmental necessity but also as a promising platform for sustainable hydrogen production. Our studies and reviews for advanced wastewater treatment methods – namely, electrochemical, photocatalytic, biological, and thermochemical processes but the sol-gel approach enhanced the morphology of the spinel structure. Among these, electrochemical methods such as electrocoagulation and microbial electrolysis cells have shown hydrogen yields up to 1.2 m3 of wastewater under optimised conditions, while photocatalytic degradation using solar-assisted systems reports quantum efficiencies reaching 8-12% with Hydrogen rates around 250 µmol/h·g_cat. Thermochemical gasification of sludge can yield 4-5 wt% of Hydrogen from dry biomass. The incorporation of spinel-type catalysts enhances these processes. Spinels such as AlFe2O4, with other transition metals, Co, Mn, Zn, and Ni, have demonstrated excellent redox stability, high oxygen evolution reaction activity, and resistance to deactivation under wastewater treatment conditions. For instance, Aluminium used in photoelectrochemical water splitting under restimulated sunlight achieved a current density of 12 mA/cm2 at 1.23 V vs RHE, with a Faradic efficiency of over 85%, but another spinel not receive a higher yield of hydrogen. This review highlights the synergistic role of spinel oxides in wastewater valorisation and hydrogen production, emphasising the importance of material engineering and process optimisation to drive sustainable energy and environmental goals. Aluminium ferrite (AlFe₂O₄), a spinel-structured mixed metal oxide, has garnered significant attention for its multifunctional role in both wastewater treatment and hydrogen production. Its inherent physicochemical properties—namely, high thermal and chemical stability, redox-active metal centres, and magnetic separability—render it an efficient and reusable catalyst. In wastewater treatment applications, AlFe₂O₄ exhibits remarkable activity in heterogeneous Fenton-like oxidation processes, facilitating the degradation of recalcitrant organic pollutants via hydroxyl radical generation. The presence of Fe³⁺/Fe²⁺ redox cycling, synergistically enhanced by Al³⁺ substitution, improves electron transfer kinetics and structural robustness under operational conditions. Furthermore, AlFe₂O₄ serves as a promising catalyst in hydrogen evolution reactions (HER) and thermochemical water-splitting cycles, where its band structure and surface characteristics promote charge carrier separation and catalytic efficiency. The dual applicability of AlFe₂O₄ in environmental remediation and sustainable energy systems underscores its potential as a cost-effective and scalable material platform for integrated catalytic technologies. Proton exchange membrane fuel cells (PEMFCs) represent a leading technology for clean and efficient energy conversion, relying on the continuous supply of high-purity hydrogen gas as the primary fuel. In PEMFC systems, hydrogen undergoes electrochemical oxidation at the anode, producing protons and electrons that are utilised to generate electric power, while oxygen reduction occurs at the cathode to form water as the sole by-product. The sustained operation of PEMFCs necessitates a reliable hydrogen source, either from compressed hydrogen cylinders, metal hydrides, or in situ hydrogen generation systems such as reforming or hydrolysis. The choice of electrocatalyst is crucial to achieving high performance and durability; platinum (Pt) remains the benchmark anode and cathode catalyst due to its excellent catalytic activity and stability. However, efforts to reduce Pt loading have led to the development of Pt-alloys (e.g., Pt-Co, Pt-Ni) and non-precious metal catalysts (e.g., Fe-N-C materials) with enhanced catalytic efficiency and cost-effectiveness. The hydrogen supply rate must be precisely controlled to meet the stoichiometric and pressure requirements of the fuel cell stack, typically maintaining a hydrogen flow rate of 0.5–1.0 NL/min per 1 kW of power output. Efficient humidification, thermal management, and membrane hydration are also critical to sustain proton conductivity and overall system performance. This abstract highlights the integrated considerations of hydrogen delivery, catalyst optimisation, and fuel cell operating conditions essential for the continuous and efficient operation of PEM-based hydrogen fuel cells. Aluminium dross, a high-temperature by-product generated during the aluminium smelting and recycling process, represents a significant secondary resource rich in metallic aluminium and alumina phases. Its valorisation for hydrogen production not only offers a sustainable waste management strategy but also contributes to renewable energy generation. The residual metallic aluminium in the dross readily reacts with water in alkaline or acidic media, producing hydrogen gas through a corrosion-driven hydrolysis reaction. Among the various approaches, alkaline-mediated hydrolysis, particularly using NaOH or KOH solutions, is considered the most efficient due to its ability to suppress the passive oxide layer on aluminium particles, thereby enhancing reaction kinetics. The primary reaction, 2Al+2NaOH+6H2O→2NaAl(OH)4+ 3H2 proceeds exothermically and can be optimised by adjusting parameters such as temperature, pH, particle size, and stirring speed. The use of mechanical activation (e.g., ball milling) and additives such as gallium or bismuth has been reported to further increase hydrogen yield by disrupting the protective alumina layer. Post-reaction residues primarily consist of alumina and sodium aluminate, which can be further utilised in industrial applications. This method not only enables the efficient extraction of hydrogen from aluminium dross but also aligns with circular economy principles by converting metallurgical waste into valuable energy resources. Traditional storage solutions such as high-pressure cylinders (>350 bar) or cryogenic tanks (<20 K) are limited by high energy requirements, infrastructure costs, and inherent safety risks. In contrast, metal–organic frameworks (MOFs) have emerged as a class of advanced porous materials with tenable pore architectures and ultrahigh specific surface areas, making them highly suitable for reversible hydrogen physisorption. MOFs such as MOF-5, HKUST-1, and MIL-101 exhibit promising gravimetric and volumetric storage capacities under moderate pressure (10–100 bar) and cryogenic conditions (~77 K), with some achieving near or above 7 wt% H₂ uptake. Their modular chemistry allows for structural optimisation toward enhanced binding enthalpies and sorption kinetics. Integrating MOF-based hydrogen storage systems with aluminium dross-derived hydrogen generation platforms can enable on-demand hydrogen capture and controlled release, addressing key bottlenecks in storage and transport, and paving the way for scalable hydrogen energy systems. Furthermore, coupling the stored hydrogen with PEM fuel cells enables clean energy conversion with high efficiency and zero emissions. Continued development in catalyst engineering—particularly low-Pt or non-precious metal catalysts—can enhance the cost-effectiveness and durability of PEMFCs. Research must also address the dynamic integration of hydrogen generation, real-time storage regulation, and fuel cell load response for practical deployment. In the broader context of circular economy and energy resilience, this combined approach has the potential to transform metallurgical waste into a clean energy vector. Future research should focus on system-level optimisation, lifecycle assessment, techno-economic analysis, and scalability of the integrated platform to support industrial and off-grid energy applications.AlFe2O4 is a visible light active spinel ferrite semiconductor with a narrow bandgap (1.9-2.1 eV), which might occur, allowing it to absorb light when light hits AlFe2O4. AlFe2O4 + hv – e- + h+ The electron (e-) goes to the conduction band, and the hole pairs are generated in the valence band. Conduction band Electrons (e-). Electrons reduce protons in water to generate hydrogen gas. 2H+ + 2e- = H2 H+ +organic contaminants = oxidation products (e.g., CO2, H2O). Holes oxidise organic matter in wastewater, aiding degradation. $$