The Vision Behind BlueCities Network
Saurabh Gupta, founder and CEO of Earth5R, opened the sustainability meetup under the BlueCities Network with a compelling overview. Earth5R began in Mumbai and has since expanded operations across 65 countries, focusing on a triple bottom line approach that integrates environmental, economic, and social impacts in all its projects.
One key concern driving the network is the deteriorating condition of rivers and water bodies in urban India. While the ideal “blue” rivers are turning gray or black due to pollution, their state also reflects the effectiveness of urban sustainability practices such as solid waste and water management.
To mobilize community engagement, BlueCities Network uses rivers as a central theme — highlighting their foundational role in civilization and urban life. The network, currently active in India, is rapidly expanding globally, aiming to foster collaboration and knowledge-sharing among sustainability professionals.
Structure and Purpose of the BlueCities Network Meetups
- The network encourages sharing real-world projects and impacts to avoid siloed efforts and redundant work.
- Meetups feature professionals presenting concise 5-minute talks with four slides, maximizing participation.
- Post-presentation discussions foster interaction and idea exchange.
- In-depth follow-up podcasts provide a platform for detailed exploration of important topics.
Speaker 1: Dr. V Prakash Ranjan — Microplastic Pollution from Paper Cups
Dr. V Prakash Ranjan
Background
Dr. V Prakash Ranjan, Assistant Professor in Environmental Engineering at IIT Jammu, specializes in solid waste management, circular economy, and microplastic pollution. His philosophy is grounded in nature-approving sustainable actions, emphasizing practical and scientific approaches.
Research Focus: Hidden Microplastic Release from Disposable Paper Cups
Dr. Ranjan’s groundbreaking research challenges the common perception that paper cups are eco-friendly alternatives for hot beverages. His study revealed that many such cups, lined internally with HDPE (High-Density Polyethylene) plastic, release thousands of microplastic particles when exposed to hot liquids.
Key Findings
- Tested five popular disposable paper cups in Indian urban markets.
- Four out of five cups were lined with HDPE plastic, not biodegradable material.
- Each cup, when filled with 100 ml of hot beverage, released approximately 25,000 microplastic particles.
- Detected microplastics ranged from 150 nanometers to 4.75 micrometers in size.
- Harmful heavy metals such as lead, nickel, and fluoride were found exceeding permissible limits in most samples.
- Hot liquid temperature triggers release of microplastics and metals almost instantaneously.
Broader Implications
- These microplastics not only affect human health via consumption but also contribute to urban pollution, clogging drainage systems and exacerbating flooding risks, as seen in cities like Ahmedabad.
- The research urges re-evaluation of policies and consumer awareness, particularly the misleading labeling of such paper cups as eco-friendly.
- Dr. Ranjan advocates for expanded studies and joint collaborations to monitor microplastic pollution across cities and to examine other overlooked sources such as construction waste plastic (e.g., cement bags fragmenting into microplastics).
Policy and Awareness Efforts
- His published work has gained recognition from the Ministry of Education and international media.
- Educational campaigns, such as displays at public institutions, help raise awareness of the risks associated with disposable paper cups.
- Dr. Ranjan calls for policy reforms that address microplastic pollution and improve waste management practices aligned with BlueCities Network’s goals.
Q&A Highlights
- Why HDPE plastic lining? Contrary to assumptions about low-density plastic (LDPE) or bioplastics, most paper cups contain HDPE lining, which is more persistent and problematic.
- How do lead and nickel leach out? The sudden exposure to hot beverages causes rapid plastic degradation, releasing toxic metals alongside microplastics.
- Community Training and Outreach: Dr. Ranjan conducts trainings during vacation periods to educate communities about microplastic pollution and sustainable waste practices.
Addressing Plastic Sustainability and Microplastic Challenges: Insights from Experts
As India transitions into the summer vacation period, many training programs focused on environmental sustainability are organized during these months. A key discussion during one such session addressed critical questions on the sustainability of industrial-grade plastic oil production and the pervasive issue of microplastics in water bodies.
Sustainability of Industrial-Grade Plastic Oil
A question arose regarding the production of industrial-grade oil from Low-Density Polyethylene (LDPE) and its sustainability. The expert highlighted that the critical factor is not whether the plastic is industrial grade or not, but whether the plastic material can withstand temperatures without degrading harmful substances.
Experiments showed that temperatures around 85-90°C could cause plastic to release toxins, regardless of grade, posing health risks if, for example, hot beverages are poured into containers made from such plastic.
While pyrolysis—a method of chemical recycling—can produce oil from plastic waste, it is often economically unviable compared to mechanical recycling, which allows for multiple cycles of reuse. Pyrolysis and gasification, although technically feasible, are generally considered last-resort solutions.
The Complex Problem of Microplastics in Lakes and Rivers
Removing microplastics directly from lakes and ponds remains a formidable challenge. The consensus is that prevention at the source is the most effective strategy since current technologies to extract microplastics economically from large water bodies are lacking. This issue has gained increasing attention, with research underway to track microplastic flow from the Himalayas through rivers and groundwater.
Intriguingly, microplastic contamination has been detected even 20 meters below ground level in some areas, indicating deep infiltration into groundwater systems. The realization that microplastics are not confined to surface pollution but are pervasive in the environment underscores the urgency for innovative solutions.
Transitioning from Plastic to Compostable Alternatives: The Phyton Approach
Following the discussion on plastic challenges, the session introduced Mr. Santosh Nagaswami, CEO of Phyton Bioengineering, a Bangalore-based material science company pioneering compostable alternatives to single-use plastics. His presentation focused on scalable, eco-friendly packaging and agricultural products that eliminate microplastic residues.
Santosh emphasized that plastics themselves are not the enemy—they have revolutionized medicine, food packaging, and countless other fields. The issue lies in the misuse and improper disposal of plastics. Phyton’s mission is to create polymers that do no harm and enrich the environment wherever possible.
Innovative Compostable Packaging and Agricultural Films
Phyton has developed a range of compostable products, including carry bags, pouches, and bin liners, that outperform existing solutions in sustainability. Their clientele includes industry leaders like Country Delight and Toyota, with whom Phyton is working to transition packaging to fully compostable materials, incorporating a circular economy model where used packaging is recollected, reprocessed, and reused.
One of their flagship innovations is a compostable mulch film designed to replace conventional plastic mulch used in agriculture. Traditional plastic mulch prevents soil moisture evaporation and weed growth but fragments under UV exposure into micro- and nanoparticles that contaminate soil, disrupt microbial life, and eventually enter the food chain.
Phyton’s mulch film lasts between three to five months—matching the growing cycle of short-term crops like tomatoes—and then biodegrades naturally, consumed by soil microbes much like an orange peel. The company also provides machinery to convert residual mulch into biochar, a soil enhancer that supports microbial ecosystems critical for soil fertility.
This product has seen successful pilots across 250 acres with top seed producers globally and in India, marking a significant step toward solving the problem of agricultural plastic pollution.
The Ubiquity and Impact of Microplastics
Santosh highlighted the staggering extent of microplastic pollution, noting its presence even in remote locations like the North Pole and deep ocean trenches where human activity is minimal. Studies reveal that humans ingest microplastics roughly equivalent to the size of a credit card each week, primarily through contaminated food and water sources.
This alarming reality drives Phyton’s commitment to creating solutions that effectively support bans on single-use plastics and provide real-world, scalable alternatives.
Challenges with Compostable Plastics in the Market
Despite growing awareness and regulatory bans, many so-called compostable plastics fail basic biodegradability tests, such as the d-chloromethane test that distinguishes true bioplastics from conventional plastics. Plastic films are still widely visible in everyday settings like local Kirana stores, reflecting the gap between policy and practice.
Phyton’s efforts focus on setting a new standard in the industry, offering products that genuinely break down and reduce environmental harm, pushing the agenda beyond mere bans toward effective implementation.
Speaker 2: Santosh Nagasamy — Insights For Tackling Plastic Pollution
Mr. Santosh Nagasami
Background
Santosh Nagasami is the CEO of Phyton Bioengineering, a Bangalore-based material science company at the forefront of developing compostable alternatives to single-use plastics. With a strong focus on environmental sustainability and scalable innovation, Santosh leads Phyton’s mission to engineer eco-friendly packaging and agricultural solutions that leave no microplastic residues.
A proponent of responsible material use, he advocates for a balanced perspective on plastics—recognizing their immense value in sectors like healthcare and food safety while addressing the urgent need to curb their environmental impact through smarter design and disposal. Under his leadership, Phyton is pioneering the shift toward polymers that not only biodegrade safely but also contribute positively to the ecosystems they return to.
The Reality of Testing in the Industry
Santosh emphasized the importance of rigorous testing in the sustainability field. “Everyone who works in this industry should have that particular test,” he said. “I have personally tested about 15 or 20 of my competitors and 80% of them have failed.” He expressed concern over those entering the sustainability space purely for profit, highlighting that “you can make money anywhere — not in this place.”
Microplastics: More Than Just Tiny Particles
According to Santosh, microplastics themselves might not be the biggest problem. Instead, the focus should be on the toxic chemicals they carry. “Microplastics are just vehicles transporting chemicals like endocrine disruptors, lead, arsenic, and cyanide into the system.” These harsh chemicals and heavy metals are used to improve plastic production efficiency but pose severe health and environmental risks.
He explained the mechanism behind chemical leaching: “While polymers are tightly held, the masterbatches containing slip agents are loosely held and can leach out at slightly elevated temperatures.” This explains why a new car left in the sun emits a strong plastic smell — a warning sign of harmful volatile compounds.
Sources of Microplastics: Tires, Clothes, and Packaging
When asked about the leading contributors to microplastics in the environment, Santosh identified tires as the number one polluter, due to friction releasing microplastics into the environment—a problem currently without an effective solution.
The second largest contributor is synthetic clothing, especially poly-cotton blends, which release microfibers during washing that enter water systems. The third contributor is food and product packaging.
Santosh called for policy interventions such as bans and rigorous testing to prevent greenwashing and urged collective action, stating, “Saving the world is not a one-man job. It takes an army.”
Bioplastics: The Compostability Conundrum
Santosh addressed questions about bioplastics, particularly compostability, from panelists and experts.
PBAT vs PLA: Understanding Compostability
Dr. V Praash asked whether bioplastics like PBAT and PLA are compostable under industrial or home conditions.
Santosh explained that PBAT (Polybutylene Adipate Terephthalate) is fossil-based but soil-compostable, meaning natural soil microbial activity can break it down. In contrast, PLA (Polylactic Acid) is plant-based but requires industrial composting facilities with high temperature and microbial activity to break down; PLA does not decompose in natural soil effectively.
Thus, despite PLA’s plant origin, it’s not compostable in typical soil environments, while PBAT is. However, each has trade-offs depending on application, such as the unsuitability of a composting water bottle that decomposes while in use.
Innovations in Bioplastic Fillers: Going Beyond Calcium Carbonate
Santosh revealed that while most bioplastics use calcium carbonate as a filler, his company developed a soil-based multi-mineral filler that contains 30-40% actual soil compounded into polymers. This filler is microbe-eaten to become biomass, enriching soil rather than polluting it. This breakthrough reduces the ecological footprint of compostable plastics, addressing concerns about filler buildup in soil long-term.
Future of Bioplastics: Research on PHA
Santosh also mentioned research on PHA (Polyhydroxyalkanoate), a bacterial fermented polymer that is compostable in every medium — soil, landfill, water — but currently five times more expensive, limiting widespread adoption.
Addressing Microplastic Pollution: Emerging Technologies and Challenges
Professor Narama from IIT Hyderabad raised questions about technologies to collect and segregate microplastics.
Santosh shared ongoing research into:
- Elomeration: Using electrical charge to clump microplastics into larger particles that can be separated.
- Bacteria that eat plastic: Experimental approaches releasing bacteria to biodegrade plastics, though concerns remain about unintended consequences.
He stressed the urgency of tackling microplastics, noting that plastic particles have crossed the blood-brain barrier and accumulated in humans, posing unknown health risks.
Hope from History: Lessons from Leaded Fuel Phase-out
Santosh offered a hopeful perspective by comparing the plastic crisis to the historic global effort to ban leaded fuel. Despite leaded fuel’s severe toxic impact, including a documented drop in global IQ by 20 points, the world united over 20 years to phase it out.
He believes a similar global response is possible for plastics, aided by today’s connected society and platforms amplifying the urgency and solutions.
Bridging the Gap: Making Sustainable Packaging Affordable
Santosh discussed working with municipalities at the grassroots level to make bioplastic packaging commercially viable even for small shops. He is collaborating with the municipality of Indore to make it plastic-free by offering low-margin products that do not financially burden local businesses. The goal is to scale this model as a benchmark for other regions.
Speaker 3: Priyanshu Kumath, CEO of Clean Water- Insights In Nature-Based Water Body Rejuvenation
The session then transitioned to Priyanshu Kumath, founder and CEO of Clean Water, an Indo-based startup focused on reviving polluted water bodies using low-cost nature-based solutions.
Mr Priyanshu Kumath
Background and Focus
Priyanshu holds a civil engineering degree from IIT Bombay and has diverse experience across startups before founding Clean Water.
He highlighted their shift from building sewage treatment plants (STPs) to focusing on scalable nature-based products for water quality restoration because many STPs are either non-functional or do not fully remove pollutants, especially nutrients that promote invasive species growth.
Nature-Based Solutions
Clean Water’s portfolio includes:
- Floating wetlands
- Floating aerators
- Beneficial microbial cultures
These solutions biologically remove pollutants such as heavy metals, nutrients, and organic contaminants from lakes, ponds, and rivers.
Successful Projects and Impact
Priyansh shared success stories including:
- Horses Shamsi Lake, Delhi: Rejuvenated to control invasive duckweed.
- Piplana Lake, Indore: Despite a functioning STP, invasive species thrived; nature-based solutions maintained water quality within norms.
- Annapurna Lake, Indore: Previously a “dead lake” with mass fish mortality and water hyacinth infestation, now showing signs of recovery.
The Innovating Scalable Solutions for Water Body Restoration in India
Water bodies across India face severe pollution, eutrophication, and biodiversity loss due to unchecked waste discharge and ecological neglect. BlueCities is pioneering a scalable, nature-based approach that combines floating wetlands, solar aerators, and microbial cultures to restore water quality efficiently and sustainably. Here’s an overview of their approach, impact, challenges, and future directions.
The Problem: Pollution and Degraded Water Bodies
Many water bodies in India receive religious waste, ritual offerings, industrial effluents, and untreated sewage. This pollution leads to zero dissolved oxygen levels, resulting in fish kills and harmful ecological impacts. For instance, some lakes had oxygen levels at zero, causing all fish to die.
The water quality deterioration affects not only aquatic life but also human use. Traditionally, polluted water cannot be reused or safely accessed, worsening water scarcity and public health issues.
BlueCities’ Nature-Based, Scalable Solution
Floating Lotus-Shaped Solar Aerators
BlueCities designed a 35-foot diameter floating solar aerator weighing 1500 kg, shaped like a lotus, which oxygenates lakes efficiently. Unlike conventional aerators powered by electricity via cables (which risk theft and damage), this product is solar-powered and floats on the water, integrating solar panels with decorative petals that also beautify the water body.
This innovation provides continuous aeration, improving dissolved oxygen and supporting aquatic life.
Floating Wetlands with Biomedia
Their floating wetlands consist of plants on top of a buoyant island embedded with biomedia made from recycled plastics. This biomedia provides surfaces for beneficial bacteria to colonize, which perform 80-90% of the water purification by breaking down organic pollutants.
Plants contribute about 10-20% of treatment by absorbing nutrients and some heavy metals. Together, these wetlands effectively reduce pollutants like BOD, COD, nitrates, phosphates, and some heavy metals.
Beneficial Microbial Cultures
Powdered microbial cultures containing friendly bacteria are also deployed to accelerate biodegradation and nutrient removal.
Results and Impact
- Water quality improvements have met and exceeded Indian Standards (IS 10500), achieving not only bathing but also drinking water quality at some sites.
- Treated lakes show reduced invasive species like water hyacinth and duckweed.
- Sludge digestion reduces methane emissions, cutting greenhouse gases.
- No mosquito breeding occurs, reducing waterborne diseases.
- Floating systems are climate-resilient, able to float through floods and droughts.
- The restored water can be reused, helping alleviate water scarcity.
BlueCities has successfully implemented this model across multiple states — including Delhi, Gujarat, Tamil Nadu, Karnataka, Himachal Pradesh, Haryana, and Uttar Pradesh — and received awards such as Jal Shakti’s Water Hero and Jal Prahari.
Scalability and Sustainability Model
- Plug-and-Play Deployment: Products are manufactured centrally and shipped nationwide. Installation takes about one day without heavy infrastructure.
- Space-Efficient: Floating products require no additional land, critical since many lakes are encroached.
- Community Involvement: Partnerships with local communities and corporates (via CSR) ensure ongoing maintenance, preventing re-deterioration.
- Financial Sustainability: Innovative revenue models like eco-friendly advertising around lakes help cover maintenance costs without harming ecosystems.
- No Direct Government Tenders: BlueCities primarily collaborates with NGOs, corporates, and community groups, avoiding bureaucratic hurdles while indirectly supplying governments through distributors.
Challenges: Emerging Contaminants and Limitations
- Industrial Effluents & pH Extremes: Biological solutions cannot treat raw acidic/basic industrial waste. Such pollutants must be stopped at the source.
- Persistent Pollutants (PFAS/“Forever Chemicals”): These compounds resist biodegradation and require source control.
- Microplastics: No current biological treatment exists for microplastics in water bodies.
- Pharmaceuticals and Personal Care Products: Some selective plants can degrade certain pharmaceuticals, but the uptake capacity is limited and still under research.
Future Directions and Collaborations
BlueCities seeks to:
- Explore advanced plant species and microbial consortia capable of degrading emerging contaminants.
- Partner with experts working on constructed wetlands and pharmaceutical pollutant degradation.
- Scale their product line through impact investment and grant funding.
- Expand community and private-sector partnerships to multiply restored water bodies.
Audience Q&A Highlights
- Preventing Untreated Discharges: Enforcement lies with government authorities, who currently have little incentive to act due to political and economic challenges.
- Floating Wetlands Function: The plants are just the visible part; the real treatment happens via bacterial biofilms on biomedia underneath.
- Addressing Large Complex Lakes: Solutions can be tailored; e.g., in lakes with crocodiles, aerators might be replaced with microbial cultures to boost oxygen.
- Handling Eutrophication: Reducing nutrient levels starves invasive species like water hyacinth, allowing manual removal and ecosystem recovery.
Overcoming Challenges in River Rejuvenation: Insights from Experts
Rejuvenating rivers poses unique challenges compared to lakes due to their dynamic flow and extensive pollution sources. Priyanshu, highlights key limitations and strategies for river restoration.
Practical Limits and Pollution Control at the Source
Unlike lakes, where floating wetlands can cover significant water surfaces, rivers cannot be fully covered due to their continuous flow and large size.
“You can’t cover 100% of a lake’s surface with floating wetlands—typically just 5 to 20%. This means that while these technologies help, stopping pollution at its source remains essential.”
The continuous inflow of pollutants from upstream industrial discharge, sewage, and solid waste complicates restoration efforts. Effective rejuvenation requires coordinated regional action to control pollution entry points.
“For example, cleaning the Yamuna river requires synchronized efforts from Delhi, Uttar Pradesh, and Haryana. Without cutting off industrial waste at the source, downstream water quality cannot improve.”
Technologies for Flowing Water Bodies
Ongoing work adapts floating wetland technology to river environments, complemented by physical barriers to intercept trash and check dams to regulate water flow and sedimentation.
“We are deploying floating trash barriers and planning check dams along rivers to manage plastics and sludge. Combined with point-source pollution control, these interventions can significantly improve river health.”
The Complex Social and Political Dimensions
Addressing river pollution also involves navigating social challenges such as encroachments on riverbanks and lack of buffer zones, which serve as natural protective barriers.
“Implementing buffer zones often requires displacing thousands of people living on riverbanks. This is difficult without political will, compensation funds, and strong enforcement.”
Many settlements along rivers are decades or centuries old, complicating removal or rehabilitation efforts.
Case Study: Oshiwara River Approach
A phased plan developed for the Oshiwara River in Mumbai includes:
- Installing water quality monitoring stations at regular intervals to identify pollution hotspots.
- Pinpointing specific waste discharge points.
- Systematically redirecting wastewater to treatment plants.
- Verifying improvements with continuous data.
This methodical, stepwise approach helps break down the larger challenge into manageable parts and can be scaled for use in major rivers.
Raising Awareness and Accountability
On the topic of awareness, Somitra emphasizes the importance of public pressure and informed citizen action to compel authorities to regulate industrial pollution more effectively.
“People need to understand the direct health risks of pollution—such as deformities and reduced lifespans in heavily contaminated river stretches—and demand accountability.”
He advocates for using tools like Right to Information (RTI) requests and legal recourse through bodies like the National Green Tribunal to enforce pollution control regulations.
Somitra also highlights the critical role NGOs play in advocacy, as profit-driven companies often lack incentives to lead these initiatives unless tied to branding or CSR goals.
Comprehensive Monitoring for Effective Standards
Responding to queries on discharge standards, a comprehensive approach is necessary, covering dozens of water quality parameters—from nutrients to heavy metals and emerging contaminants.
“Targeting just a few pollutants is insufficient. Comprehensive testing guides precise interventions tailored to each water body’s needs.”
However, many organizations prioritize superficial reporting and CSR optics rather than investing in rigorous water quality improvements.
Conclusion and Future Directions
The panel discussion underscored the multifaceted challenges involved in restoring India’s water bodies, emphasizing that effective solutions require a combination of innovative technologies, robust policy enforcement, and active community participation. The complexity of addressing pollution, social factors, and ecological dynamics demands coordinated efforts across governmental agencies, local communities, and the private sector. Continued dialogue, knowledge sharing, and transparency will be crucial to sustaining momentum and driving meaningful progress. As these initiatives advance, integrating scalable nature-based solutions with strong monitoring frameworks can pave the way for healthier, more resilient water ecosystems that support both people and biodiversity.
