By Oliver Charles Harry - Founder and Creative Director of Ghini Como, a silk scarf brand based in Argegno on Lake Como
Quick facts: silk and sustainability
- Silk is a renewable, biodegradable protein fibre that decomposes within one to five years in soil, returning peptides and amino acids to the ground with no toxic residue; polyester, by contrast, is a petroleum-derived polymer that does not biodegrade within any human-relevant timeframe
- A systematic review published in Environmental Science and Technology found that polyester textiles release between 210 and 72,000 microplastic fibres per gram of fabric per wash, with figures for a single polyester garment ranging from hundreds of thousands to over one million fibres per wash cycle depending on fabric construction and washing conditions
- The Bombyx mori silkworm completes its reproductive cycle in 45 to 55 days, meaning the raw material for silk replenishes on a biological schedule rather than a geological one - unlike petroleum, from which polyester is derived
- Silk production is not without environmental cost: the cocoon-processing and dyeing stages are energy-intensive and contribute greenhouse gas emissions, particularly where coal-powered electricity is used; this article addresses that nuance directly
- The global silk market was valued at approximately USD 18.6 billion in 2024 and is projected to nearly double by 2033, with mulberry silk dominating production - a growth trajectory driven in significant part by consumer demand for natural, biodegradable alternatives to synthetic textiles
The environmental case for natural silk: why mulberry silk is fashion's most sustainable luxury
One of the greatest tragedies of modern fashion is its reliance on cheap, man-made materials that destroy the environment, wear poorly and are uncomfortable to interact with over time.
When I started Ghini Como, I knew I only wanted to work with purely natural materials that bear no negative impact on the environment.
This inevitably brings us to silk, which is what we use to create all of our scarves.
But why is silk so sustainable, and does it really live up to the hype of being luxury fashion's most sustainable material?
Well, the sustainability credentials of any textile material can only be assessed honestly by examining the full lifecycle - from raw material origin through production, use, and end-of-life disposal - and by comparing that lifecycle against the alternatives it replaces.
Mulberry silk, assessed on this basis, has a strong and specific environmental case that is distinct from the greenwashing that surrounds much of the luxury fashion industry's sustainability claims.
However, it also has real environmental costs, which we will explore in this article.
The raw material: renewable and agriculturally derived
The foundation of silk's environmental advantage over synthetic alternatives is the nature of its raw material.
Polyester is manufactured from polyethylene terephthalate (PET), a polymer derived from petroleum - a finite, non-renewable fossil resource whose extraction and refining carry a substantial carbon burden before a single fibre has been produced.
Mulberry silk begins instead with the white mulberry tree (Morus alba) and the Bombyx mori silkworm, both of which operate on biological cycles rather than geological ones.
Mulberry trees regrow, silkworms reproduce on a 45 to 55-day cycle, and the finished fibre biodegrades without leaving microplastics or toxic residues.
No fossil fuels are needed to create the raw material itself. This distinction - renewable biological feedstock versus finite petrochemical feedstock - is the structural difference from which most of silk's environmental advantages follow.
Biodegradability: what it means in practice
Silk is completely biodegradable, breaking down naturally within one to five years through biological processes that enrich soil with nutrients.
The degradation products are peptides and amino acids - the same compounds found throughout natural soil systems - with no toxic residues and no persistent microplastic fragments.
Polyester does not biodegrade within any human-relevant timeframe. A polyester garment discarded today will remain in some physical form in the environment for centuries, progressively fragmenting into smaller particles but never returning to nature in the way that a protein fibre does.
The distinction matters at scale: the global textile industry produces approximately 92 million tonnes of waste annually, and the majority of that waste is synthetic fibre that will persist in landfill and waterways indefinitely.
Microplastics: the specific harm of synthetic textiles in use
The environmental impact of polyester does not begin at end-of-life. Research published in Environmental Science and Technology found that 12 different polyester textiles demonstrated great variability in microplastic fibre release, ranging from 210 to 72,000 microplastic fibres per gram of textile per wash.
These fibres pass through sewage treatment systems and enter waterways, where they accumulate in river sediment, ocean water, and marine organisms.
Microplastic contamination has now been identified in human blood, lung tissue, and placental tissue in multiple peer-reviewed studies, though the long-term health implications remain an active area of research.
Silk, as a protein fibre, does not shed microplastics. When silk is washed, any released fibres are protein fragments that biodegrade in water and soil rather than accumulating as persistent synthetic particles.
For a buyer who washes a silk scarf correctly once or twice a year, this distinction is largely academic in terms of individual impact - but at the scale of a global textile industry in which polyester accounts for approximately 54% of all fibre production by volume, the aggregate effect of micro-plastic shedding is substantial and measurable.
The honest accounting: where silk's environmental costs are real
A credible environmental case for silk requires acknowledging where the material's sustainability credentials are genuinely limited rather than presenting a one-sided argument.
Sericulture - the cultivation of silkworms and the processing of their cocoons - involves energy-intensive stages that carry a real carbon cost.
Unlike polyester, silk is biodegradable and does not shed microplastics, but its energy-intensive cultivation and processing undermine its green credentials in regions where coal-powered electricity is the norm.
The boiling of cocoons to soften sericin and enable reeling, the heating of incubators during larval development, and the dyeing and finishing processes used in textile production all require energy inputs whose carbon cost depends entirely on the energy source used.
In the Como district specifically, Italy's national grid has a substantially lower carbon intensity than the coal-heavy grids of major Asian silk-producing regions, which partially offsets the energy cost of processing.
The small-run, artisan production model used by Como's family mills also produces less waste per metre of fabric than industrial-scale synthetic production, since the precision of small-run printing reduces the volume of rejected fabric. These are genuine but partial advantages rather than absolute ones.
The conventional sericulture process also involves the killing of the silkworm pupa in the cocoon stage - a necessary consequence of preserving the continuous filament. This is an ethical consideration separate from the environmental one, and it is relevant to buyers for whom animal welfare is part of their purchasing calculus.
Longevity as an environmental argument
The most straightforward environmental case for silk over synthetic alternatives is the one that requires the least scientific qualification: a high-quality silk scarf maintained correctly lasts for decades, while a polyester alternative degrades within one to three years of regular use.
The environmental cost of producing one silk scarf, worn and maintained over fifteen years, is fundamentally different from the environmental cost of producing five or six polyester scarves over the same period to replace ones that have worn out.
This durability argument is independent of the biodegradability, microplastic, and renewable feedstock arguments - it stands on its own as the most accessible reason why choosing a 14 momme mulberry silk scarf from a producer with a transparent supply chain represents a more considered environmental choice than the synthetic alternative, regardless of the buyer's position on the finer points of lifecycle analysis.
What "sustainable luxury" actually means for Como silk
Como silk production at artisan scale combines natural protein fibre, small-run production with minimal waste, a short supply chain within a geographically contained district, and a product designed for decades of use rather than seasonal replacement.
Together, these factors represent a version of luxury that is inherently more sustainable than the high-volume, synthetic-dominated fast fashion model.
That claim does not require overstating the environmental perfection of any production process, because the evidence supports it on its own terms.
At the end of its useful life, silk can break down and return to the soil. The degradation products are just peptides and amino acids, the same building blocks found throughout nature, with no toxic residues.
For a buyer choosing between a product derived from petroleum that will persist in the environment for centuries and a protein fibre that completes a biological cycle, that distinction is both real and relevant - provided it is presented transparently by the brand you are purchasing from.
Oliver Charles Harry is the founder and creative director of Ghini Como, a luxury silk scarf brand which sources its silk entirely from the Province of Como, Italy. He lives in Argegno on the western shore of Lake Como.
