What Is Green Chemistry? Ahloki’s Approach to Fragrance Ingredients

If Ahloki is a botanical brand, why does it use synthetic fragrance ingredients? It is a fair question, and one worth answering properly. The short version is that the word “natural” describes a source, not a standard of safety or sustainability. The longer version involves some genuinely interesting science about how fragrance molecules are made, how they behave and what they cost the environment.

What Green Chemistry Actually Is

Green chemistry is a scientific approach to designing chemical products and manufacturing processes that reduce or eliminate the use and generation of hazardous substances. Rather than waiting until waste or pollution has been created and finding ways to manage it, the idea is to prevent unnecessary harm at the design stage.

The field emerged during the early 1990s, influenced by work at the United States Environmental Protection Agency. In 1998, chemists Paul Anastas and John Warner published the twelve principles of green chemistry, establishing a framework that continues to influence research, industrial manufacturing and product development.

These principles address more than the toxicity of an individual ingredient. They consider how efficiently raw materials are used, how much waste a process generates, the hazards associated with solvents and other processing chemicals, the energy required for manufacturing, the use of renewable resources and what happens to a chemical after it has served its purpose.

One particularly important principle is prevention. It is better to avoid producing hazardous waste than to create it and subsequently find a way to treat or dispose of it.

Another is known as atom economy. In chemical synthesis, this describes how efficiently the atoms in the starting materials become part of the intended product rather than ending up in unwanted byproducts. A reaction that incorporates most of its starting materials into the desired molecule can be more efficient than one that generates substantial waste.

Then there is the principle of designing chemicals for degradation. Ideally, products should perform their intended function and, after use, break down into substances that do not persist or cause unnecessary environmental harm.

Other principles encourage the use of catalysts, safer solvents, more efficient manufacturing conditions and renewable raw materials where these offer genuine benefits.

These are not simply environmental aspirations. They influence real decisions in chemical manufacturing, including how fragrance ingredients can be produced.

But green chemistry is not a certification that automatically makes an ingredient safe or sustainable. A manufacturing process may perform well against one principle while raising concerns under another. Renewable raw materials, for example, may reduce dependence on fossil resources while creating greater demands for agricultural land or water.

Understanding these tradeoffs requires looking at the entire process rather than selecting whichever characteristic sounds most environmentally reassuring.

And this is where green chemistry becomes particularly relevant to fragrance.

Green chemistry is not opposed to synthetic ingredients. It asks whether chemistry can be designed and used more responsibly, regardless of where the starting material comes from.

Why “Natural” Is Not a Synonym for “Green”

This is the part that often surprises people.

A natural fragrance ingredient may begin with a flower, tree, leaf or resin, but getting that material into a bottle can require considerable resources.

Some aromatic plants yield only very small quantities of essential oil. Large volumes of flowers, leaves, bark or wood may need to be cultivated, harvested and processed to produce a relatively modest amount of concentrated fragrance material.

Steam distillation requires heat and water. Other extraction methods may involve solvents, specialised equipment or additional processing stages. Agriculture brings its own demands for land, irrigation, fertilisers and energy, while wild harvesting raises questions about biodiversity, regeneration and pressure on vulnerable plant populations.

None of these methods is automatically irresponsible. Extraction systems differ considerably, and efficient production, responsible cultivation, solvent recovery and the productive use of plant residues can all improve environmental performance.

But botanical origin does not eliminate those impacts.

Certain aromatic materials have also faced serious conservation pressures. Rosewood, Indian sandalwood and some species used to produce agarwood demonstrate how commercial demand, illegal harvesting and habitat loss can threaten valuable botanical resources.

The problem is not that these materials come from nature. It is that nature does not necessarily replenish them at the rate commercial demand requires.

Consider linalool, a fragrance molecule associated with the floral character of lavender and present in numerous other aromatic plants.

Linalool can be obtained from botanical sources or produced through industrial chemical processes. The molecule’s identity does not change simply because it has a different origin, although the precise chemical composition and characteristics of a finished botanical extract will differ from those of an isolated ingredient.

Obtaining linalool from a botanical source may involve growing, harvesting and processing substantial quantities of plant material. Producing it through another route may avoid some of those agricultural demands but introduce different inputs, including chemical feedstocks, energy and manufacturing waste.

Which route is more environmentally responsible?

It depends.

A well managed botanical supply chain may perform better than an inefficient chemical process. Equally, an efficient synthetic route may place considerably less pressure on land, water and vulnerable plant species.

This is why the question cannot be answered by looking at the word natural on a label.

How Green Chemistry Is Changing Fragrance Production

To understand the opportunity, it helps to look at how fragrance ingredients can be manufactured.

Traditional perfumery has relied extensively on ingredients obtained directly from plants, including essential oils, absolutes, resins and expressed citrus oils. These remain important materials, not least because a botanical extract may contain dozens or even hundreds of different chemical constituents contributing to its aroma.

Synthetic chemistry gives perfumers another possibility: producing individual aroma molecules or developing alternatives that recreate particular scent characteristics.

A laboratory does not necessarily reproduce the full complexity of a botanical extract. Instead, it may provide a specific molecule with a particular olfactory function, allowing the perfumer to build a fragrance composition using materials from several different sources.

The environmental value of this approach depends on how those molecules are manufactured.

One important development is catalysis. A catalyst makes a chemical reaction possible or more efficient without being consumed in the same way as an ordinary reactant. Carefully designed catalytic processes can improve yields, reduce unnecessary chemical steps and sometimes lower energy requirements.

Another is biotechnology.

Certain aroma molecules can now be produced using biological systems such as microorganisms or enzymes. Fermentation processes, for example, can use selected microorganisms to convert suitable feedstocks into useful compounds.

Biocatalysis uses enzymes to carry out particular chemical transformations, sometimes under milder conditions than conventional manufacturing methods.

These approaches are particularly interesting when they can reduce dependence on scarce botanical materials or avoid inefficient chemical reactions.

But fermentation is not automatically environmentally preferable. A fermentation process still needs nutrients, water, energy, equipment and downstream purification. If the feedstock is an agricultural crop, its production carries environmental impacts of its own. If substantial energy is required to isolate and purify the finished molecule, some of the anticipated benefit may be reduced.

The same applies to synthetic ingredients made from renewable biological feedstocks. A renewable starting material is not proof of a low environmental footprint. The important scientific question is whether a particular manufacturing route genuinely reduces relevant impacts compared with the available alternatives. This is the opportunity green chemistry offers the fragrance industry. Not simply replacing plants with laboratories, but finding more efficient and responsible ways to create the aromatic materials that perfumery needs.

What the Scientific Evidence Actually Tells Us

There is a useful distinction between making a chemical process greener and demonstrating that the resulting ingredient has a lower overall environmental impact. One way researchers investigate this is through life cycle assessment, commonly called LCA.

Life cycle assessment examines environmental impacts across defined stages of a product’s existence. Depending on the scope, it can consider raw material extraction, agricultural production, chemical manufacturing, energy use, transport, product use and eventual disposal. This matters because improving one part of a process does not necessarily improve the whole.

An ingredient manufactured with less energy could still require environmentally intensive raw materials. A renewable ingredient could involve substantial land use. An efficient extraction method could still depend on harvesting a botanical species under ecological pressure.

In a 2023 study published in the scientific journal Green Chemistry, researchers from L’Oréal, fragrance manufacturer MANE and environmental consultancy EVEA assessed 27 fragrance ingredients using life cycle assessment alongside a tool based on green chemistry principles.

The findings were revealing.

Environmental impacts varied considerably between ingredients, including ingredients within the same broad production category. The researchers found that renewable origin did not necessarily result in lower environmental impact than fossil origin.

They also identified important opportunities for improvement, including raw material selection, production yields, transformation processes and solvent use.

The study did not establish that synthetic fragrance is always more sustainable than natural fragrance. It demonstrated something more useful: the environmental performance of an ingredient depends on its actual production system, not simply the category to which it belongs.

There is another important limitation worth understanding. Environmental comparisons are only as informative as their available data and the boundaries of the assessment. A study focused on ingredient production does not necessarily tell us everything about what happens during consumer use or disposal.

For a brand choosing fragrance materials, this means green chemistry principles offer a valuable starting point, while meaningful environmental comparisons require evidence that goes beyond an ingredient’s description. That distinction is important to Ahloki. We can choose to work towards more considered formulation without pretending that every environmental tradeoff can already be measured or resolved.

The Distinction Between “Synthetic” and “Harmful”

The words synthetic and harmful are often treated as though they mean the same thing.

They do not.

Every aromatic plant owes its fragrance to chemistry. Lavender, rosemary, cedar and citrus release volatile molecules that interact with receptors in our noses. It is these chemical structures, rather than the marketing category attached to them, that help determine their smell and behaviour.

A linalool molecule does not become inherently safer because it came from lavender, nor inherently more dangerous because it was manufactured through a chemical process.

But chemical identity is only the beginning of a proper safety assessment.

Toxicologists distinguish between hazard and risk.

Hazard describes the potential of a substance to cause harm. Risk considers the likelihood of that harm occurring under particular conditions of exposure. The amount of a substance matters. So does how it enters the body, how frequently exposure occurs, how long it lasts and whether an individual has particular sensitivities.

A substance that causes adverse effects at a high experimental dose may present a different level of risk at much lower concentrations during ordinary use. Conversely, certain substances can cause allergic reactions in susceptible individuals at comparatively low exposures.

This is why responsible fragrance assessment considers both the properties of ingredients and how a finished product is intended to be used. There is another complication that rarely appears in consumer discussions of natural fragrance.

Some aromatic molecules can change chemically when exposed to air. Linalool and limonene, both commonly found in botanical fragrance materials, can undergo oxidation. Research has shown that some oxidation products, particularly hydroperoxides, can be more potent causes of skin sensitisation than the original compounds.

In other words, a molecule’s behaviour can change as it reacts with its surroundings.

This evidence is especially relevant to understanding fragrance allergies and the storage and formulation of products that contact the skin. It should not be interpreted as proof that ordinary candle exposure causes the same effects. Nevertheless, it illustrates an important scientific principle.

Safety is not determined by origin alone. It depends on chemical properties, concentration, exposure and, sometimes, the reactions that occur after an ingredient has been produced.

This brings us to fragrance regulation.

The International Fragrance Association, known as IFRA, develops standards for the safe use of fragrance materials. These standards draw on scientific safety assessments conducted by the Research Institute for Fragrance Materials and reviewed through an independent expert process.

They may restrict the use of certain ingredients, specify maximum concentrations for particular applications or prohibit materials where necessary.

Importantly, the standards distinguish between different categories of product use. A fragrance intended for a candle is not evaluated in precisely the same way as a fragrance intended for a cosmetic applied directly to the skin.

An IFRA certificate of conformity is therefore relevant to the intended application and the concentration at which a fragrance mixture is used.

However, it does not replace a complete assessment of the finished product, nor does it prove that a candle produces no emissions when burned. In Great Britain, chemical substances are also subject to applicable legislation including UK REACH and classification and labelling requirements. The European Union operates its own REACH system.

These regulatory frameworks are separate from green chemistry principles. Compliance establishes important legal and safety responsibilities, while green chemistry encourages manufacturers to go further by considering how chemical products and processes can be improved.

What Happens to Fragrance When a Candle Burns?

This is an important part of the conversation because the environmental and safety characteristics of an ingredient do not end when it enters a finished product.

A scented candle is a combination of wax, fragrance, wick and vessel, and its behaviour depends on how those components work together.

When a candle is lit, heat melts the wax surrounding the wick. The liquid wax travels upwards through the wick by capillary action. Near the flame, wax vapour forms and undergoes combustion, producing heat, light and combustion products.

Meanwhile, some fragrance molecules evaporate from the warmed wax and disperse into the surrounding air.

This is how we experience much of a candle’s scent.

But the process is more complicated than fragrance simply evaporating unchanged.

Some fragrance molecules may be exposed to high temperatures and undergo chemical transformation. The flame itself produces combustion products, and incomplete combustion can generate substances including particulate matter and soot.

Research measuring emissions from scented and unscented candles has identified a mixture of airborne substances, including combustion products and volatilised fragrance constituents.

In a controlled experimental study published in Environment International in 2021, researchers examined candles made using different waxes and fragrance mixtures. They measured gaseous pollutants, volatile organic compounds and particles under controlled conditions.

For most of the exposure scenarios modelled, concentrations were below the guidance values used by the researchers, although some pollutants and scenarios warranted greater scrutiny.

That distinction is important. Detecting a chemical emission does not automatically mean the resulting exposure is hazardous, but neither should the presence of an IFRA compliant fragrance be interpreted as proof that a burning candle has no impact on indoor air.

Room size, ventilation, burning duration, candle construction and flame behaviour can all influence exposure.

There is another piece of chemistry worth understanding.

Many fragrance molecules are volatile organic compounds, or VOCs. Volatility simply describes a substance’s tendency to enter the gas phase. It does not, by itself, tell us whether that substance is harmful.

Some volatile fragrance molecules, including certain terpenes, can react with ozone in indoor air. Under suitable conditions, those reactions may produce secondary compounds, including formaldehyde and very small airborne particles.

This chemistry can occur with molecules from natural sources as well as synthetic ones. It is influenced by the concentrations of the reacting substances and the conditions in the room.

It also explains why biodegradability and indoor air behaviour are not the same thing.

Biodegradation generally refers to the breakdown of substances through biological processes, often assessed in environmental compartments such as water or soil. Atmospheric reactions involve different processes and timescales.

An ingredient that biodegrades under a particular test method is not necessarily removed harmlessly from indoor air, just as an ingredient that reacts quickly in the atmosphere is not automatically safer.

For Ahloki, this reinforces the importance of considering fragrance as part of an entire candle system rather than assessing a molecule in isolation.

The wax, wick, fragrance concentration, stability, burning characteristics and conditions of use all matter.

It is also why sensible candle care remains important. Maintaining an appropriate wick length, avoiding excessive flickering or smoking, using candles in ventilated rooms and following the manufacturer’s burning instructions can help support more consistent burning.

The intention is not to suggest that candles should be feared.

It is to recognise that bringing fragrance into a living space involves chemistry, and that understanding it allows us to make more informed choices.

How Ahloki Applies This in Practice

Ahloki began with a desire to make more thoughtful choices about the ingredients, materials and products we bring into our homes.

Green chemistry provides a useful framework for that ambition, although it is important to distinguish between applying its principles to product decisions and claiming that every ingredient or manufacturing process has been independently verified as environmentally superior.

We are not a chemical manufacturer producing every fragrance molecule ourselves. We work with materials and fragrance blends supplied through the wider fragrance industry. That makes ingredient selection, supplier information, formulation and responsible product development particularly important.

When considering fragrance ingredients and finished blends, there are several questions that matter to us.

What is the ingredient, and what evidence supports its safe use?

We consider the intended application and the relevant IFRA Standards, including the suitability of fragrance blends for use in candles.

IFRA conformity is an important foundation, but it is not a blanket guarantee of safety in every circumstance. Appropriate formulation, finished product considerations and compliance with applicable regulations remain necessary.

Where does the ingredient come from?

For botanical materials, responsible sourcing involves looking beyond the plant name to questions of cultivation, harvesting, extraction and ecological pressure.

For synthetic ingredients, we are interested in the raw materials and processes used to make them, including whether more efficient routes or renewable feedstocks may offer environmental benefits.

There is no assumption that one source is inherently preferable to another.

Does the alternative genuinely offer an improvement?

A synthetic or nature identical aroma molecule may avoid dependence on a scarce botanical resource. But reducing pressure on a plant population is not the same as demonstrating a lower carbon footprint across every stage of production.

Where reliable comparative data are available, they can inform more considered decisions. Where such data are unavailable, we should be careful not to present assumptions as established environmental facts.

How does the fragrance perform in the finished candle?

Fragrance performance is not simply about creating the strongest scent.

The interaction between wax, fragrance concentration and wick influences how a candle burns and how its aroma is released.

A well considered fragrance blend should work within the candle system, rather than relying on excessive fragrance loading as a substitute for thoughtful formulation.

What about the rest of the product?

At Ahloki, our candles use a plant-based rapeseed and soy wax blend and are hand-poured in England.

The decision to use plant-based wax reflects our preference for renewable agricultural feedstocks, but we do not assume that plant-based automatically means impact-free or that one wax type is always environmentally superior under every comparison.

Responsible decisions extend to the vessel, packaging, transport, product longevity and what can reasonably be reused or recycled.

These choices sit alongside fragrance selection as part of the same wider philosophy.

We want the materials we choose to make sense not just individually, but as part of a product intended to be enjoyed and used in someone’s home.

Why Green Chemistry Is a Continuing Responsibility

There is something reassuring about simple labels.

Natural. Clean. Green. Sustainable.

They offer the impression that a complicated set of decisions has already been made for us.

But chemistry rarely works that way.

A plant-based ingredient can involve intensive agriculture. A synthetic molecule can be manufactured through an inefficient and resource intensive process. A renewable feedstock may reduce dependence on fossil resources while placing new pressures on land or water. An ingredient may satisfy a relevant safety standard without that standard answering every question about environmental impact.

These are not contradictions. They are part of the complexity of making things responsibly.

Green chemistry gives us a better way to approach that complexity. It encourages us to prevent unnecessary harm, improve processes, question material choices and consider what happens beyond the moment a product is manufactured.

It also requires honesty about the limits of what we know.

A fragrance can be beautiful and still have an environmental footprint. A botanical can be precious without being sustainable in every context. A synthetic ingredient can offer a responsible alternative without automatically becoming the better choice.

Ahloki is a botanical brand because nature, scent and the relationship between fragrance and our surroundings remain central to what we create.

But appreciating nature does not mean believing that everything derived from a plant is inherently virtuous, or that everything produced in a laboratory is suspect.

Our approach is to consider the science, the sourcing, the safety and the purpose of each material, while recognising that responsible formulation is an ongoing process of learning and improvement.

We are interested in making better decisions, not simply making better sounding claims.

Because the most meaningful question is not whether an ingredient can be described as natural.

It is whether we understand enough about that ingredient to make a genuinely considered choice.