DU 301: The Environmental Considerations of Raw Denim

By Eric Steffen
Founder / Maker
FITTED Underground

I'll be honest with you: I came into this topic with a point of view, and the research both confirmed and complicated it. Raw denim is not a perfect environmental choice. Cotton farming, however you slice it, is water-intensive and has real costs. But once you understand the full picture — the chemistry of distressing, the science of synthetic fabrics, the math of longevity — raw denim looks considerably better than most of its alternatives. This article is an attempt to lay out that picture honestly without advocacy. The facts I found are interesting enough to stand on their own. Here we go.

The Water Question

The most widely cited environmental figure in denim is this: producing a single pair of jeans consumes approximately 3,781 liters of water — roughly 1,000 gallons — across its entire lifecycle. That number tends to generate alarm, and it should generate some. But understanding where that water actually goes changes the conversation considerably.

Of that total, 92% comes from cotton farming. Not from the factory. Not from the dyeing process. Not from finishing. The overwhelming majority of the water footprint of a pair of jeans is embedded in the field, in the irrigation of the cotton plant itself. Conventional cotton is one of the thirstiest crops in commercial agriculture, requiring between 7,000 and 29,000 liters of water per kilogram of lint, depending on where and how it is grown.

This means the water problem is fundamentally an agricultural problem, not a manufacturing one. And it means that improvements at the farm level — through organic farming, regenerative agriculture, and precision irrigation — have far more impact on the water footprint of a pair of jeans than any improvement at the factory level. More on that in a moment.

The remaining 8% of water use — from dyeing, washing, and finishing — is not inconsequential, but it is dwarfed by the upstream footprint. And in the case of raw denim, which skips most industrial finishing processes entirely, even that fraction is reduced.

The Finishing Problem: A Ranked Guide to Distressing Techniques

Here is something most consumers never think about: the fades on a pair of pre-distressed jeans were put there by chemicals and machines, at real cost to the environment and in many cases to the workers applying them. When you buy raw denim, you are opting out of this system entirely. The fades come from wear. From you. That choice has genuine environmental consequences.

To understand what you're opting out of, here is a ranked guide to conventional denim finishing techniques, from least to most harmful:

1. Laser Finishing — Least Harmful

The cleanest option in industrial finishing. CO₂ lasers etch fades, whiskers, and patterns directly onto denim with no water, no chemicals, and minimal energy compared to wet processes. Precise, consistent, and scalable. Laser finishing represents the gold standard of sustainable distressing — the industry is adopting it slowly due to high equipment costs, but it is the clear direction of travel. Some reduction in fabric strength is the main downside.

2. Ozone Washing — Low Impact

Ozone gas (O₃) is used in place of chlorine bleach and large volumes of water to fade and lighten denim. Ozone is a natural oxidant that breaks down indigo dye without leaving toxic residues — it converts back to oxygen after use. Significantly lower water use, no hazardous chemical discharge, achievable at room temperature. A major improvement over conventional wet processes. Some technical challenges remain around fabric strength, but ozone washing is increasingly considered best-in-class for sustainable wet finishing.

3. Enzyme Washing (Bio Stone Washing) — Moderate, but Far Better Than Stone

Cellulase enzymes — biodegradable proteins — are used to mimic the abrasion effect of stone washing without the pumice. A few grams of enzyme replace kilograms of stones. A 2025 comparative study found enzyme washing uses 10.6% less water, 1.9% less energy, produces 73% lower chemical impact scores, and generates 23x less suspended solid waste in effluent compared to conventional stone washing. The wastewater is significantly cleaner. Enzyme washing is 100% ZDHC (Zero Discharge of Hazardous Chemicals) compliant. Not without environmental footprint, but dramatically better than what it replaces.

4. Stone Washing — Significant Impact

The original industrial distressing method. Jeans are tumbled with pumice stones — volcanic rock — in large washing machines. A single run of 100 pairs of jeans uses approximately 250 pounds of pumice and 140 gallons of water for one hour of washing. More intense stonewashes run four to six hours. The stones create pumice sediment that must be filtered from wastewater, and they physically degrade the machines and the jeans. Better than the chemical alternatives below, but a significant resource draw by any measure.

5. Chlorine and Acid Bleaching — Harmful

Chemical bleaches — sodium hypochlorite (chlorine bleach) and various acid compounds — are used to achieve light washes and high-contrast distressed looks. These chemicals generate toxic wastewater that must be neutralized and treated before discharge, and they are frequently not properly treated in lower-cost manufacturing environments. The effluent from denim finishing facilities using these methods has turned rivers blue, brown, and sometimes black in denim-producing regions of Bangladesh, India, and China. Harmful to aquatic ecosystems and to the communities downstream.

6. Potassium Permanganate (PP) Spray — Most Harmful

The worst of the commonly used finishing chemicals, and one of the denim industry's worst-kept dirty secrets. PP spray is used to create bright, localized bleaching effects — the crisp white patches on heavily distressed jeans. It is an oxidizing agent classified as hazardous by the European Chemicals Agency: toxic to aquatic life, causes severe skin burns and eye damage, harms fertility, and damages organs with prolonged exposure.

Denim sandblasting — PP's predecessor — was banned in Turkey in 2009 after killing more than 120 workers with silicosis, a fatal lung disease caused by inhaling silica dust. PP became the replacement. It may not be any safer. Workers spray it by hand in enclosed workshops, often without adequate protection. A 2024 Clean Clothes Campaign report documented ongoing worker exposure in the Ergene Basin in Turkey, where surrounding agricultural land is now considered unsuitable for farming due to chemical contamination. PP was added to the ZDHC Foundation's Chemical Watchlist in early 2026, and major brands are under pressure to phase it out. Alternatives exist. Adoption has been slow.

Raw denim requires none of the above. No sandblasting, no PP spray, no acid bleach, no stone washing, no enzyme bath, no laser etching. The fabric leaves the loom dark and raw. The distressing happens over years of wear, through the natural interaction of body, movement, and indigo. This is not an incidental feature of raw denim. It is the point.

The Cotton Dilemma: What's in the Fabric Matters

Cotton is simultaneously the best and worst thing about denim. It is natural, breathable, strong, and — critically, as we'll discuss — biodegradable. But how that cotton is grown shapes its entire environmental story.

Conventional Cotton

The dominant form of cotton agriculture globally. High-yield, extensively irrigated, heavily reliant on synthetic pesticides and fertilizers. The pesticide load of conventional cotton farming is significant — cotton accounts for roughly 6% of global pesticide use despite covering only 2.5% of arable land. Soil degradation, water table depletion, and chemical runoff into waterways are established consequences of industrial cotton farming at scale.

Organic Cotton

Grown without synthetic pesticides or fertilizers, and largely rain-fed rather than irrigated. The water difference is dramatic: organic cotton cultivation uses an average of 182 liters of water per kilogram of lint, compared to 2,120 liters for conventional cotton — a reduction of more than 90%. Organic cotton also supports healthier soil biology, greater biodiversity, and better farmer health outcomes. The catch: organic cotton currently accounts for only about 1% of global cotton supply — and typically costs 20–30% more. FITTED Underground is actively moving toward incorporating more organic cotton selvedge into our product line, which we believe is the right direction to go — both for the quality of the fabric, the integrity of the supply chain and the experience of our customer. 

Recycled Cotton

Made from post-consumer denim and other cotton waste, mechanically processed into new fiber. Significantly lower water and energy requirements than virgin cotton — no farming required. The trade-off is fiber length: mechanical recycling shortens cotton fibers, which reduces the strength and feel of the resulting fabric. Typically blended with virgin cotton to achieve acceptable quality. A promising direction for reducing the footprint of high-volume production. 

Hemp

Possibly the most compelling alternative fiber in this conversation. Hemp requires approximately 50% less water than conventional cotton, grows in roughly half the time, needs little to no pesticide, and actively improves soil health by drawing down carbon and suppressing weeds. Hemp fiber is exceptionally strong — estimated to last significantly longer than comparable cotton under normal wear. In denim, hemp is typically blended with cotton at ratios of 20–55%, because pure hemp denim can be stiff, though it softens considerably with wear. The environmental credentials are strong; the mainstream supply chain is still developing. It is a fiber worth watching closely.

The 98/2 Cotton/Elastane Question

This blend deserves honest treatment, because it is extremely common — not just in mass-market stretch denim but even in some raw denim. Elastane (also sold as spandex or Lycra) is a petroleum-derived synthetic fiber. Even at 2% of a garment's composition, it creates a serious problem at end of life: elastane is essentially impossible to separate from cotton using conventional mechanical recycling. A garment that is 98% cotton and 2% elastane cannot be meaningfully recycled — the elastane contaminates the cotton fiber and the entire garment is typically destined for landfill, where the elastane component will persist for 20–200 years.

There is also the microplastics dimension. Even a 2% elastane content means the garment sheds synthetic microfibers during wear and washing — in smaller quantities than a fully synthetic garment, but measurably. Emerging bio-based alternatives to elastane exist, but they are not yet mainstream.

At FITTED Underground, are moving away from stretch blends, with a preference for 100% cotton selvedge. The fit challenge that elastane is typically used to solve — accommodating bodies that don't conform to standardized sizing — we address differently, through custom size options and in-store alterations. We think that's the better answer.

What Happens When It's Done: Cotton vs. Synthetics

End-of-life is where the environmental story of fabric becomes most stark.

100% cotton denim biodegrades readily. Under composting conditions, cotton fabric loses 30–90% of its mass within 15–90 days. In a Cornell University study, denim jeans buried in a compost pile began breaking down within a month — after five months, only the synthetic components remained. Cotton microfibers biodegrade in freshwater, saltwater, and wastewater treatment environments. In a landfill, biodegradation is slower due to anaerobic conditions, but cotton still breaks down in months to years rather than centuries.

Polyester takes 20 to 200 years to degrade. It is made from the same petroleum-derived polymer as PET plastic water bottles — a fact that carries new significance as we learn more about what happens to plastic as it breaks down.

The Microplastics Alarm

This is the part of the environmental conversation about synthetic fabrics that most people haven't fully reckoned with yet — and the science emerging in 2024 and 2025 is increasingly difficult to dismiss.

Synthetic fabrics — polyester, nylon, acrylic, and spandex/elastane — shed microscopic plastic fibers during wear and washing. These microplastic fibers are now found essentially throughout the human body: in blood, in liver and kidney tissue, in breast milk, and in the tonsil tissue of children. A 2024 UCSF systematic review, the first conducted using gold-standard National Academy of Sciences methods, concluded that microplastic exposure is suspected to contribute to harm in the reproductive, digestive, and respiratory systems, and suggested a link to colon and lung cancer. A separate landmark study analyzed tumor samples from 61 patients with various cancers and found microplastics present in higher concentrations in cancerous tissues than in adjacent healthy tissue across multiple cancer types.

It is important to be precise here: causal links between microplastics and cancer in humans have not yet been definitively proven. The science is still developing, and much of the most compelling evidence comes from animal and cell studies. What we can say accurately is that the trajectory of the research is alarming, that microplastics are now present in human biology in ways they were not a generation ago, and that multiple research institutions are calling for urgent action.

100% cotton denim sheds no microplastics. Cotton microfibers, when shed, biodegrade. This distinction may, as the science matures, prove to be one of the most important arguments for natural fiber clothing available.

The Solutions: What's Being Done About the Water Problem

The water footprint of cotton is the hardest problem to solve, because it is rooted in agriculture rather than manufacturing. But meaningful work is underway.

Organic farming is the most immediately impactful change. The shift from irrigated conventional cotton to rain-fed organic cotton can reduce per-kilogram water consumption by more than 90%. The challenge is scale: the three-year certification transition period is a barrier for many farmers, and demand signals from brands are the most effective accelerant.

Regenerative agriculture goes a step further. Where organic farming focuses on what you don't use, regenerative farming focuses on what you actively restore: soil health through cover cropping and reduced tillage, carbon sequestration through improved soil organic matter, biodiversity through crop rotation and habitat management. Farms practising regenerative methods have shown dramatically higher pollinator activity, improved water retention, and reduced input costs over time. A 2024 study in Gujarat found regenerative farms recorded 62.6% higher bee activity than control farms and nearly double the plant species. The key insight: better soil absorbs and retains water more efficiently, directly reducing irrigation demand.

Precision irrigation — using soil moisture sensors, satellite data, and AI-driven advisory tools — allows farmers to apply water where and when the crop actually needs it, rather than on a fixed schedule. U.S. cotton production has improved irrigation water efficiency by 58% over recent decades through these technologies. Significant room for further improvement remains, particularly in India and Pakistan.

Alternative fibers — hemp, linen, and blends incorporating these crops — directly reduce the cotton content of denim and its associated water footprint. EU regulation requiring 30% low-impact fibers in garments by 2030 is creating real incentive for fiber diversification at scale.

And then there is the direct answer: wear what you have, longer. The most powerful tool available to an individual denim wearer for reducing environmental impact is simply not buying a new pair. A pair of jeans worn 1,000 times has a per-wear water footprint approximately 10–20 times smaller than one worn 50 times and replaced. The environmental argument for raw denim is inseparable from the behavioral argument: you wear it more, wash it less, repair it instead of replacing it, and you love it too much to throw it away.

The Slow Fashion Multiplier

Everything above comes down to this.

The 3,781 liters of water and 33.4 kilograms of CO₂ embedded in a pair of jeans are fixed at the point of production. What happens to those numbers over time depends entirely on what you do with the jeans. A pair worn 1,000 times — the realistic lifespan of a well-made raw denim jean that is cared for, washed sparingly, and repaired when needed — amortizes that footprint across a decade. The per-wear environmental cost becomes genuinely small.

Raw denim enforces a different relationship with clothing. It doesn't look best on day one — it looks best on day 500, after it has been broken in, faded by your specific life, and begun to tell a story that is entirely yours. That relationship makes replacement psychologically difficult in a way that a pair of mass-market jeans does not. The fades make it irreplaceable. The investment — financial and temporal — makes it worth repairing. The beauty that comes with age makes it worth keeping.

This is not incidental to the environmental argument. It is the environmental argument, stated in human terms. Buy fewer things. Buy better things. Wear them until they tell a story. The jeans will teach you the rest.

An Honest Summary

Raw denim is not a perfect environmental choice. Cotton farming carries real costs regardless of what happens downstream, and there is no clothing that is truly free of environmental footprint.

But compare it to the realistic alternatives. Compared to conventionally finished denim — with its stone washing, chemical bleaching, and potassium permanganate spray — 100% cotton raw selvedge is dramatically cleaner at the factory level and dramatically longer-lived at the consumer level. Compared to synthetic fabrics — polyester, nylon, acrylic, spandex — 100% cotton is biodegradable, does not shed microplastics, and does not deposit petroleum-derived particles in human tissue. Compared to fast fashion of any material, the math of longevity is simply not close.

Organic cotton, worn long, washed rarely, repaired when needed. That is the raw denim proposition. And it is, on the available evidence, a good one.

What Comes Next

The environmental case for raw denim depends on one behavioral commitment above all others: washing less, and washing right. How you wash your jeans — when, how often, and by what method — has more impact on their longevity and environmental footprint than almost any other choice you make. That's DU 302: How to Wash Raw Denim.

← Previous: DU 206 — Where to Shop for Raw Denim in NYC  |  Next: DU 302 — How to Wash Raw Denim →

Further Reading

• Will the Denim Industry Ever Ban Potassium Permanganate? — Sourcing Journal
• Cotton vs. Synthetics: The Truth About Biodegradability — Cotton Incorporated
• Microplastics in the Air May Be Leading to Lung and Colon Cancers — UCSF
• Regenerative Agriculture and Cotton — CottonWorks

Eric Steffen is the founder of FITTED Underground, a custom jeans and raw denim workshop at 108 Bayard Street in Williamsburg, Brooklyn. He has been making jeans by hand since 2014. Denim University is his attempt to share everything he's learned — about the history, the craft, and the culture behind the world's most enduring garment.