Patricia
Martz
*a,
T. V. Tony
Phan
*b,
Jacques
L'Haridon
a,
Marie-Hélène
Beausoleil
a,
Kévin
Lafaye
c,
Yves
Gérand
c and
Cyril
Gallardo
b
aL'Oréal Recherche & Innovation – Innovation Durable, 1 avenue Eugène Schueller, 93600, Aulnay-sous-Bois, France. E-mail: jacques.lharidon@loreal.com; patricia.martz@loreal.com
bMANE, 620 route de Grasse, 06620, Le Bar-sur-Loup, France. E-mail: tony.phan@mane.com
cEVEA, 3 rue Michel Rambaud, 69006, Lyon, France. E-mail: k.lafaye@evea-conseil.com
First published on 28th July 2023
In the last few decades, sustainability has become one of the main challenges of beauty companies driven by growing consumer demand for more natural-based cosmetics. Fragrances playing a major role in cosmetic formula, they have to be taken into account in the eco-design process of cosmetics. The composition of fragrances can imply up to one hundred different fragrance ingredients, but is most of the time kept secret to protect the professional knowledge of fragance's suppliers. Different eco-design tools exist, based for example on green chemistry principles and metrics. These tools may address various environmental impacts or life-cycle steps, from the single E-factor indicator, which focuses on the amount of waste per amount of product at the production step, to an elaborated set of indicators, like in the GREEN MOTION™ tool developed by MANE. On the other hand, to assess the holistic environmental impacts of products over their whole life-cycle, Life Cycle Analysis (LCA) is the most recognized method. However, it requires extensive amounts of data which can be difficult to obtain or inaccessible for various reasons, including confidentiality. To compare these different possible approaches of fragances eco-design, the results of an LCA of 27 selected fragrance ingredients are compared to those obtained with the green chemistry tool GREEN MOTION™. Fragrance ingredients were found to have a wide range of environmental impacts, depending on their production process and on the starting raw material used. Overall, tendencies observed on results with the 2 tools are in good accordance. This study therefore showcases the complementarity of simplified eco-design tools and metrics with LCA to address environmental impacts of fragrance ingredients. Indeed, the former can be used as a first approach to identify environmental hotspots and implement eco-design practices in the development process of fragrance ingredients, while the latter highlights potential direct and indirect impacts over the upstream life cycle and the ingredient production itself, and can be used to measure the reduction of the global environmental footprint achieved through the implementation of eco-design practices. Based on these results on fragrance ingredients, a clustering method could be developed to help conduct LCA of fragrances.
Few other LCA have been conducted on fragrance ingredients themselves. In 2019, IFF-LMR published a cradle-to-gate LCA study of rose oil and absolute conducted in collaboration with Quantis.5 The authors presented the environmental results for 5 endpoint indicators: climate change, water consumed, ecosystem quality, resources and human health. Such studies are a great source of knowledge for practitioners looking for environmental data for a particular fragrance ingredient. However, they are scarce in the literature6–9 and much more information would be needed to fully evaluate a fragrance by LCA. Yet, as the authors of this study on rose oil and absolute say, “assessing, improving and ensuring the sustainability of natural ingredients is an absolute necessity for the future of natural(s)” fragrances.5 Therefore, in the aim of improving the knowledge on fragrance environmental impacts, more data on fragrance ingredients are needed.
To address the challenge of fragrance complexity and data confidentiality which renders the application of LCA difficult, a simplified yet robust method of evaluation could be developed, taking inspiration from the variety of tools and metrics developed to answer the need for quantitative knowledge on chemical processes, in order to follow the “green chemistry” concept and its twelve principles proposed by Paul T. Anastas and John C. Warner in 1998.10 A succinct definition of green chemistry can be summarized as the design of chemical products and processes that reduce or eliminate the use and generation of hazardous substances.11 One of the significant contributions of green chemistry was the introduction of the Environmental Factor concept (E-factor) by Sheldon.12 Since then, the field expanded into a wide range of research topics from metrics13–17 to LCA-based tools and hybridized metrics.18–23
All these tools based on green chemistry principles address environmental issues at the chemical structure level by designing more efficient syntheses or processes. Thus, thanks notably to a better yield, benefits can carry on through all stages within a product or a process life cycle. It might nevertheless not always be the case, as the 12 principles of green chemistry are not independent factors24 and the application of one might be in contradiction with another.25 To quantitatively check the effective environmental performance improvement of a process redesigned following the green chemistry concept, LCA offers a comprehensive and quantitative assessment of different environmental indicators. It helps to avoid misleading results or sub-optimization of the environmental impact reduction26 by weighting different factors.27 However, green chemistry tools can complement LCA by providing useful qualitative information on aspects not taken into account by the latter.28 An example of such complementary analysis is the assessment of an innovative route to glycidol from the conversion of a by-product in the epichlorohydrin production process.29 The authors compared the new route with the current value chain by green metrics, an at early stage (AES) LCA30 and the green chemistry-based tool GREEN MOTION™31 to confirm that the proposed process was indeed leading to a decrease of the environmental impact of the epichlorohydrin value chain. However, this case study, which is the comparison of two ways of producing a molecule, one of them including the reuse of a waste as a starting material, provide an ideal case for the comparison of green chemistry-based tool and LCA conclusions since no opposing factors play a role here. The conclusions obtained with these tools could vary more when applied to the comparison of totally different production process and raw materials origin to produce radically different molecules, which is the case for fragrance ingredients.
In the fragrance sector, the use of green chemistry principles and holistic view of LCA have made their appearance in the programs of some of the key players in recent years, albeit with various degree of details.32–35 However, environmental data are still scarce and usually focus on only a few impact categories which could lead to missing out on environmental hotspots. In this context, the company MANE developed a comprehensive approach based on green chemistry principles called GREEN MOTION™31 to assess the environmental impact of all its ingredients, flavours and fragrances. Committed to a continuous improvement of its LCA based eco-design tool of cosmetic products named SPOT, L'Oréal partnered with MANE to determine the complete environmental profile of a representative selection of fragrance ingredients using LCA. The objectives of this work were multiple: (1) allow better assessment of the environmental impact of any fragrances by providing impact factors for widely-used fragrance ingredients (see ESI†), which could also benefit to several industries (cosmetics, detergents, food, pharmaceuticals, etc.), (2) compare environmental impacts obtained with LCA to GREEN MOTION™ ratings, and to a commonly-used metric such as the E-factor to help decision making on which tool to use depending on the objective of the study and (3) help to eco-design fragrance ingredients by providing details on the origin of the environmental impacts.
The LCA study focuses on the production of fragrance ingredients and on all upstream steps, while their downstream use and their end-of-life were excluded from this study as shown in Fig. 1. These steps were excluded as (1) the modeling of the end-of-life of cosmetics and of the ingredients they content depends on their use phase, and (2) methods have already been developed to assess the impact of fragrances at the end-of-life step, for example based on the hazard mentions of fragrance ingredients in the final concentrate,36 allowing to preserve the secret composition of the fragrance. The reference unit selected for the LCA is: “Production of 1 kg of the fragrance ingredient at MANE's plant”.
For its part, GREEN MOTION™, measures the health, safety and environmental impacts of the ingredients based on their level of compliance with the twelve principles of green chemistry. It includes various aspects of the life cycle including raw material, production process and end-of-life.
Finally, the E-factor focuses on the amount of waste generated by the production of an ingredient. It considers raw materials and solvents but does not include the waste generated in the upstream value chain.
Category | Definition |
---|---|
Essentials oils (EO) | Product obtained from a natural raw material of vegetable origin, either by steam distillation with or without water, mechanical processes from the epicarp of citrus fruits or dry distillation, after separation of the possible aqueous phase by physical processes |
Jungle Essence™ extracts | Product obtained from a natural raw material of vegetable origin by extraction with a supercritical fluid followed by a separation by expansion |
Essences by expression | Essential oil obtained by mechanical processes from the epicarp of the fruit of a Citrus, at ambient temperature |
Natural extracts with volatile solvent – Absolutes | Product obtained by extraction with ethanol from a concrete, a floral pomade, a resinoid or a supercritical fluid extract |
Natural extracts with volatile solvent – Resinoids | Product obtained from a dry plant natural raw material by extraction with one or several solvent(s) |
Isolated natural ingredient | Product obtained by fractional distillation as a by-product of an essential oil or extract obtained by concentration, distillation or others isolation techniques |
Bio-based ingredients with a fossil-based moiety | Product obtained by synthesis from a combination of a biosourced raw material with one or more fossil-based ingredients |
Fossil-based ingredients | Product obtained by synthesis from a combination of two or more fossil-based raw materials |
Biotechnology ingredients | Product obtained by a process involving biological entities comprising micro-organisms such as bacteria, yeasts and fungi, or higher organisms such as algae, plants or animals, used as such or in cell or tissue cultures, and enzymes derived thereof |
Category | Ingredient | Olfactive categorya | Raw material | Method of culture | Manufacturing process | Yieldb | Co-products from ingredient production | Relative expected impact in the category |
---|---|---|---|---|---|---|---|---|
a IFRA Fragrance Ingredient Glossary, April 2010 edition. b From raw material to final ingredient. c Jungle Essence™ extracts are ingredients obtained by supercritical CO2 extraction. d This category includes only Orange essence but it is still quite representative because the former is the most used ingredient by far. e Bio-based ingredients with a fossil-based moiety are ingredients obtained by chemical transformation of a natural-based raw material. f The myrcene used was assumed to be from a 50/50 mix of crude sulfate turpentine and pine sourcing. | ||||||||
Essentials oils (EO) and Jungle Essence™ extractsc | Lavender EO | Aromatic | Flower | Mechanized | Hydrodistillation | 1% | Lavender floral water | Low |
Elemi EO | Spicy | Resin | Wild harvest | 20% | — | Low | ||
Orris Butter | Floral | Rhizome | Manual | 0.35% | — | High | ||
Vetiver EO | Woody | Root | Manual | 2% | — | Low | ||
Vanilla Pure Jungle Essence™ | Gourmand | Beans | Manual | Supercritical CO2 extraction | 20% | Exhausted vanilla seeds | Middle | |
Pink Pepper Pure Jungle Essence™ | Spicy | Pink pepper | Wild harvest | 1.5% | — | High | ||
Essences by expressiond | Orange essence | Citrusy | Fruit | Mechanized | Expression | 0.01% | Orange juice (main product) | — |
Natural extracts with volatile solvent – Absolutes | Orange flower absolute | Floral | Flower | Mechanized | Solvent extraction | 0.12% | Wax | High |
Jasmine absolute | Floral | Mechanized | 0.15% | Wax | High | |||
Narcissus absolute | Green | Wild harvest | 0.07% | Wax | Middle | |||
Rose absolute | Floral | Mechanized | 0.16% | Wax | High | |||
Natural extracts with volatile solvent – Resinoids | Benzoin resinoid | Balsamic | Resin | Wild harvest | Solvent extraction | 85% | — | Low |
Labdanum resinoid | Balsamic | Leafy branches | Wild harvest | 84% | — | Low | ||
Labdanum absolute | Balsamic | 60% | — | Middle | ||||
Vanilla absolute | Gourmand | Beans | Manual | 5% | Exhausted vanilla seeds | High | ||
Isolated natural ingredient | cis-3-Hexenol (natural) | Green | Mint leaves | Mechanized | Hydrodistillation then fractionation | 0.001% | Menthol, mint terpenes (α- and β-pinene, limonene, etc.) | — |
Bio-based ingredients with a fossil-based moietye | Iso E super | Woody | Myrcenef | Mechanized/wild harvest | Chemical synthesis | 42% (from myrcene) | Middle | |
Vetiveryle acetate | Woody | Vetiver essence | Manual | 0.84% | High | |||
Myrcene (from crude sulfate turpentine) | Aromatic | Wood chips | Mechanized | 78% | α-Pinene, limonene | Low | ||
Myrcene (from pine) | Aromatic | Pine resin | Wild harvest | 4% | Colophane, α-pinene, limonene | Low | ||
Fossil-based ingredients | Hexyl salicylate | Floral | Synthetized from petrochemical materials | — | Chemical synthesis | 99.9% | — | Middle |
Ethyl 2-methyl butyrate | Fruity | — | 87% | — | Low | |||
Hedione | Floral | — | 20% | — | High | |||
cis-3-Hexenol (fossil-based) | Green | — | 42% | — | Middle | |||
Biotechnology ingredients | Antillone | Fruity | Undecylenic acid | — | Fermentation | Confidential | Confidential | Middle |
γ-Octalactone | Gourmand | Caprylic acid | — | Low | ||||
Tropicalone | Fruity | Undecylenic acid | — | Middle |
- Since wild plants harvested manually require no mechanized work, no chemical inputs nor lead to land occupation, their harvest was assumed to have no impact.
- Primary data on the resources used for each ingredient production process in MANE's plant were not available. However, aggregated water and energy data were known for 4 types of production units: natural extracts, synthesis, fractionation and biotechnologies. Specific data for each ingredient were then estimated with the assumption that energy and water consumption vary proportionally to some key parameters of the production process: duration, temperature and heating process (see ESI† for more details).
- Thus, energy overconsumption needed to pressurize CO2 into supercritical CO2 could not be specifically attributed to the ingredients that use it.
- For ingredients not produced by MANE, energy and water consumptions were extrapolated from MANE's data and adapted to the country of the supplier manufacturing site.
- Solvents used are fully recycled with a loss rate of 3.5% (data measured by MANE). Lost solvents are emitted to air. The energy necessary to recycle solvents is included in the modeling. In case of by-products in the production process of the ingredient, economic allocation was used with prices data from the manufacturer except in the case of wax by-products and exhausted vanilla beans to which no impact was attributed.
For the presentation of results, life-cycle steps of the production of the ingredients are divided as follows:
- “Raw material” groups the culture of the renewable raw materials and the production of the fossil-based raw materials necessary for the fragrance ingredients.
- “Upstream transport” refers to all transport steps between the raw materials manufacturing site to MANE's plant.
- “Transformation process” includes chemical reagents other than solvents, energy (electricity and heat) consumption, water consumption and infrastructures to extract the ingredient from the raw material. “Solvents” includes the production of solvents and the solvent loss during the recycling process, emitted to air. Recycling process of solvents is included in “transformation process”.
- “Waste” includes all waste generated during the production process of fragrances ingredients. It corresponds mainly to biowaste from the exhausted biomass for ingredients from renewable origin.
To evaluate the environmental impacts of the fragrance ingredients, the methodology of the L'Oréal's product eco-design tool (SPOT) was used. The method, aligned with the Product Environmental Footprint (PEF) method of the European Commission,43 uses the 14 impact categories described in Table 3. To help decision making, a single score is calculated via the aggregation of the normalized and weighed impacts results of LCA. Normalization is a calculation step to estimate the magnitude of impacts by dividing them by a baseline. Normalization values are given by the PEF methodology which are based on the average impacts of a world citizen.44 Weighting is then used to give more or less weight to the environmental indicators before aggregating them into a single score. For this study, values are based on the Planetary Boundaries concept45–47 (see Table 4). This transformation of results simplifies the assessment of ingredients environmental profiles with the use of a single and unitless value, instead of the 14 LCA indicators, all having different units.
Impact category | LCIA method | Unit |
---|---|---|
Climate change (CC) | GWP100, IPCC 2013 | kg CO2 eq. |
Water consumption (WC) | Water scarcity, AWARE, Boulay et al., UNEP 2016 | m3 eq. |
Ecotoxicity, freshwater (EC) | USEtox 1.0, Rosenbaum et al. 2008 | CTUe |
Eutrophication, freshwater (EF) | P equivalents, ReCiPe 2008 | kg P eq |
Eutrophication, marine (EM) | N equivalents, ReCiPe 2008 | kg N eq |
Acidification (A) | Accumulated Exceedance, Seppala et al. 2006, Posch et al. 2008 | mol H + eq |
Land use (LU) | Soil quality index, LANCA, Bos et al. 2016 | Pt |
Eutrophication, terrestrial (ET) | Accumulated Exceedance, Seppala et al. 2006, Poschet al. 2008 | mol N eq |
Mineral, fossil & ren resource depletion (RD) | ADP fossile and ultimate reserve, van Oerset al. 2002 | kg Sb eq. |
Particulate matter (PM) | PM 2.5 eq., UNEP, Fantkeet al. 2016 | Disease inc. |
Ionising radiation (IR) | Ionizing radiation potential, Frischknecht et al. 2000 | kBq U-235 eq. |
Photochemical ozone formation (POF) | POCP, Van Zelm et al. 2008 | kg NMVOC eq |
Ozone depletion (OD) | ODP, WMO 1999 | kg CFC11 eq. |
Human toxicity, cancer & non-cancer (HT) | USEtox 1.0, Rosenbaum et al. 2008 | CTUh |
Impact category | Normalization factor (multiplicative) | Weighting factor (multiplicative) |
---|---|---|
Climate change (CC) | 0.0001 | 0.2550 |
Water consumption (WC) | 0.0018 | 0.0140 |
Ecotoxicity, freshwater (EC) | 0.0001 | 0.0231 |
Eutrophication, freshwater (EF) | 0.6223 | 0.0878 |
Eutrophication, marine (EM) | 0.0512 | 0.0150 |
Acidification (A) | 0.0180 | 0.0145 |
Land use (LU) | 1.2203 × 10−6 | 0.2543 |
Eutrophication, terrestrial (ET) | 0.0057 | 0.0083 |
Mineral, fossil & ren resource depletion (RD) | 5.181 | 0.1113 |
Particulate matter (PM) | 0.0001 | 0.1625 |
Ionising radiation (IR) | 0.0002 | 0.0004 |
Photochemical ozone formation (POF) | 0.0246 | 0.0147 |
Ozone depletion (OD) | 18.64 | 0.0076 |
Human toxicity, cancer & non-cancer (HT) | 1703 | 0.0317 |
Concept | Major criterion | Unit |
---|---|---|
Raw material | Raw material origin | Category |
Process naturalness | Yes/no | |
Solvents | Solvent category | Category |
Hazard and of toxicity of the reagents | GHS pictogram | Pictogram |
Reaction | Mass yield | % |
Number of steps | Number | |
Number of solvents | Number | |
Carbon economy: number of carbons of product/number of carbon of reactants | % | |
Number of protection/deprotection step | Number | |
Overall processing time | Hour | |
Process | Most consuming heating process | Category |
Most consuming cooling process | Category | |
Vacuum | Category | |
Pressure | Category | |
Hazard and of toxicity of the final product | GHS pictogram | Pictogram |
Waste | E factor | kg kg−1 |
All data necessary to calculate GREEN MOTION™ ratings are directly collected from MANE manufacturing sites or from supplier informations.
In this study, in order to compare GREEN MOTION™ results with SPOT, GREEN MOTION™ impact was used instead of the direct score described in the original article. Instead of deducting penalty from a 100-score, penalty points are added to a starting 0-score. Thus, the relation between the impact and the score is as follows:
All types of waste were included such as spent materials after extraction, lost solvents, distillation pellets, synthesis residues, etc. Composted biowaste was also integrated into the E-factor since it was not considered as valorized products. Any valorized by-products like exhausted vanilla beans are not considered as waste for E-factor calculation.
Tool | Type of tool | Concept behind | Approach | Perimeter | Complexity |
---|---|---|---|---|---|
SPOT | Advanced model | Life-cycle assessment | Quantitative | Upstream life cycle including the production process of the ingredient. Downstream life cycle excluded in this study. | High |
GREEN MOTION™ | Simplified model | Green chemistry principles | Quantitative | Life cycle of the ingredient | Medium |
E factor | Metric | Waste measurement | Quantitative | Waste of the production process | Low |
The scope of the assessment of the three tools vary accordingly to their time and data requirements. The E-Factor is only a metric that calculates the amount of waste generated to make a product, while SPOT and GREEN MOTION™ evaluate all or a large part of the life cycle. In the case of GREEN MOTION™, the evaluation leads to the quantification of the respect of the Green Chemistry principles. All stages of the life cycle are included in this analysis, but only certain aspects are taken into account. This simplification makes it possible to quickly orient design choices. Whereas SPOT, an eco-design tool based on LCA, assess quantitatively the complete life cycle by creating inventories of flows for each step, but at the cost of collecting a lot of data.
Comparison of the production yield and E-factors of all ingredients (Table 7) shows that the latter is strongly correlated to the former. Ingredients extracted from plants in which they are in low to very low concentration (Essentials oils and Jungle Essence™ extracts, Essences by expression, Absolutes and Isolated natural ingredient) have the lowest production yield (0.001–20%) and the highest E-factor (5–106680) overall. Significant variations between those categories can be explained by the concentration of the ingredient in the plant, the plant production yield and the extraction process yield. On the other hand, ingredients extracted from plants in which they are in high concentration (Resinoids) lead to higher yields (5–85%) and lower E-factors (0.3–25). Ingredients that involve chemical synthesis steps (bio-based ingredients with a fossil-based moiety and Fossil-based ingredients), usually result in higher yields (0.84–99.9%) and lower E-factors (0.3–127) than ingredients extracted from plants. Explanations of this are the high level of optimization of chemical processes used here and the high production yield of fossil fuels based starting raw materials.
Category | Ingredient | Yield | E-Factor | GREEN MOTION™ impact | SPOT single score (mPt) |
---|---|---|---|---|---|
Essentials oils (EO) and Jungle Essence™ extracts | Lavender EO | 1% | 100 | 11 | 20 |
Elemi EO | 20% | 5 | 16 | 1.5 | |
Orris Butter | 0.35% | 285 | 43 | 46 | |
Vetiver EO | 2% | 70 | 16 | 4 | |
Vanilla Pure Jungle Essence™ | 20% | 5 | 28 | 14 | |
Pink Pepper Pure Jungle Essence™ | 1.5% | 33 | 38 | 7 | |
Essences by expression | Orange essence | 0.01% | 4470 | 24 | 0.6 |
Natural extracts with volatile solvent – Absolutes | Orange flower absolute | 0.12% | 830 | 64 | 208 |
Jasmine absolute | 0.15% | 350 | 64 | 271 | |
Narcissus absolute | 0.07% | 1500 | 58 | 209 | |
Rose absolute | 0.16% | 600 | 64 | 184 | |
Natural extracts with volatile solvent – Resinoids | Benzoin resinoid | 85% | 3 | 25 | 0.3 |
Labdanum resinoid | 84% | 0.3 | 20 | 11 | |
Labdanum absolute | 60% | 2.5 | 31 | 23 | |
Vanilla absolute | 5% | 25 | 49 | 113 | |
Isolated natural ingredient | cis-3-Hexenol (natural) | 0.001% | 106680 | 31 | 53 |
Bio-based ingredients with a fossil-based moiety | Iso E super | 42% (from myrcene) | 3 | 52 | 2 |
Vetiveryle acetate | 0.84% | 127 | 78 | 9 | |
Myrcene (from crude sulfate turpentine) | 78% | 0.4 | 34 | 0.6 | |
Myrcene (from pine) | 4% | 0.3 | 29 | 0.3 | |
Fossil-based ingredients | Hexyl salicylate | 99.9% | 10 | 61 | 1.1 |
Ethyl 2-methyl butyrate | 87% | 1.3 | 33 | 0.5 | |
Hedione | 20% | 11 | 72 | 9 | |
cis-3-Hexenol (fossil-based) | 42% | 0.1 | 57 | 0.6 | |
Biotechnology ingredients | Antillone | Confidential | 11 | 31 | 47 |
γ-Octalactone | 5 | 27 | 7 | ||
Tropicalone | 27 | 34 | 73 |
However, there are some notable exceptions to these trends: (1) vetiveryle acetate, a Bio-based ingredient with a fossil-based moiety, has a high E-factor of 127 because of Vetiver EO production (which has an E-factor of 70). (2) Myrcene from pine has the lowest E-factor of all despite having a low yield of 4%. It is since the co-products obtained during its transformation process (α-Pinene and limonene) are valorized with similar value, thus few wastes are generated. On the contrary, (3) hexyl salicylate exhibits an almost quantitative yield, but its E-factor is around 10-fold higher than the lowest E-factors. This example shows that chemical syntheses can be highly efficient but at the cost of employing additional chemicals that then need to be disposed at the end of the reaction, which lead to environmental impacts (transport, disposal, end-of-life, etc.).
Overall, it appears that the applied categorization of fragrance ingredients is relevant even though it is mainly based on ISO standard and IFRA definitions, which did not have data on the environmental profile of the ingredients. The exceptions observed mainly come from the choice to integrate ingredients with the worst and the best GREEN MOTION™ ratings. Although yield and E-factor are important metrics to gauge the environmental impact of a fragrance ingredient, more in-depth analysis is required to have a better picture of the potential hotspots.
As Table 8 shows, LCA evaluation of fragrance ingredients reveals a significative variance between categories as well as within each of them. Overall, the main contributor to environmental impacts is the production of raw materials, followed by their transformation process. In case solvents are used in the extraction process, the small fraction of solvents lost during the production (3.5%, primary data) contributes significantly to the environmental profile of ingredients, via the air pollution linked to photochemical ozone formation.
Category | Ingredients | CC | WC | EC | EF | EM | LU | ET | RD | POF | HT | Othersb | Total | Av.c | Raw material | Upstream transport | Transformation process | Solvent | Waste |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
a Total may not add up to the sum of each score due to rounded values. b Others = acidification, particulate matter, ionizing radiation and ozone depletion. c Av. = average SPOT single score of the category. | |||||||||||||||||||
Essentials oils (EO) and Jungle Essence™ extracts | Lavender EO | 2 | 0 | 2 | 1 | 0 | 5 | 0 | 1 | 0 | 9 | 0 | 20 | 18 | 20 | 0 | 0 | 0 | 0 |
Elemi EO | 0.2 | 0 | 0.8 | 0 | 0 | 0 | 0 | 0 | 0 | 0.3 | 0 | 1.5 | 0.1 | 0.1 | 0.3 | 0 | 1 | ||
Orris Butter | 8 | 0 | 3 | 1 | 0 | 30 | 0 | 1 | 0 | 2 | 0 | 46 | 30 | 4 | 11 | 0 | 0 | ||
Vetiver EO | 0 | 0 | 0 | 0 | 0 | 4 | 0 | 0 | 0 | 0 | 0 | 4 | 4 | 0 | 0 | 0 | 0 | ||
Vanilla Pure Jungle Essence™ | 2 | 0 | 0 | 2 | 2 | 7 | 0 | 2 | 0 | 0 | 0 | 14 | 14 | 0 | 0 | 0 | 0 | ||
Pink Pepper Pure Jungle Essence™ | 2 | 0 | 2 | 1 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 7 | 0 | 1 | 2 | 4 | 0 | ||
Essences by expression | Orange essence | 0.1 | 0 | 0.3 | 0.1 | 0 | 0.1 | 0 | 0 | 0 | −0.1 | 1 | 0.6 | — | 0.4 | 0 | 0 | 0 | 0.1 |
Natural extracts with volatile solvent – Absolutes | Orange flower absolute | 69 | 1 | 25 | 8 | 1 | 32 | 1 | 11 | 28 | 29 | 2 | 208 | 218 | 63 | 13 | 94 | 34 | 4 |
Jasmine absolute | 55 | 0 | 31 | 10 | 2 | 25 | 3 | 12 | 51 | 77 | 4 | 271 | 146 | 0 | 58 | 64 | 3 | ||
Narcissus absolute | 87 | 0 | 26 | 6 | 1 | 1 | 1 | 13 | 53 | 17 | 2 | 209 | 0 | 9 | 126 | 67 | 7 | ||
Rose absolute | 33 | 0 | 19 | 8 | 2 | 24 | 2 | 8 | 53 | 31 | 3 | 184 | 80 | 0 | 33 | 67 | 3 | ||
Natural extracts with volatile solvent – Resinoids | Benzoin resinoid | 0.1 | 0 | 0.1 | 0 | 0 | 0 | 0 | 0 | 0.1 | 0 | 0 | 0.3 | 37 | 0 | 0 | 0.1 | 0.1 | 0 |
Labdanum resinoid | 1 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 9 | −1 | 0 | 11 | 0 | 0 | 1 | 10 | 0 | ||
Labdanum absolute | 3 | 0 | 2 | 2 | 0 | 1 | 0 | 1 | 14 | 0 | 0 | 23 | 0 | 0 | 1 | 21 | 0 | ||
Vanilla absolute | 12 | 0 | 0 | 16 | 14 | 55 | 0 | 15 | 0 | 0 | 0 | 113 | 111 | 1 | 1 | 1 | 0 | ||
Isolated natural ingredients | cis-3-Hexenol (natural) | 8 | 0 | 5 | 5 | 3 | 11 | 2 | 2 | 0 | 13 | 2 | 53 | — | 47 | 0 | 2 | 0 | 4 |
Bio-based ingredients with a fossil-based moiety | Iso E super | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 2 | 3 | 1 | 0 | 1 | 0 | 1 |
Vetiveryle acetate | 0 | 0 | 1 | 0 | 0 | 7 | 0 | 0 | 0 | 0 | 0 | 9 | 7 | 0 | 1 | 0 | 1 | ||
Myrcene (from crude sulfate turpentine) | 0.1 | 0 | 0.1 | 0 | 0 | 0.3 | 0 | 0 | 0 | 0.1 | 0 | 0.6 | 0.4 | 0 | 0.2 | 0 | 0 | ||
Myrcene (from pine) | 0 | 0 | 0.1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0.3 | 0 | 0 | 0.2 | 0 | 0.1 | ||
Fossil-based ingredients | Hexyl salicylate | 0.3 | 0 | 0.4 | 0.1 | 0 | 0 | 0 | 0.1 | 0 | 0.2 | 0 | 1.1 | 3 | 0.6 | 0 | 0.5 | 0 | 0 |
Ethyl 2-methyl butyrate | 0.1 | 0 | 0.2 | 0 | 0 | 0 | 0 | 0 | 0 | 0.1 | 0 | 0.5 | 0.3 | 0 | 0.1 | 0 | 0.1 | ||
Hedione | 3 | 0 | 3 | 1 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 9 | 8 | 0 | 0 | 0 | 1 | ||
cis-3-Hexenol (fossil-based) | 0.3 | 0 | 0.1 | 0.1 | 0 | 0 | 0 | 0.1 | 0 | 0.1 | 0 | 0.6 | 0.2 | 0 | 0.3 | 0 | 0.2 | ||
Biotechnology ingredients | Antillone | 3 | 0 | 7 | 1 | 1 | 4 | 0 | 3 | 0 | 28 | 0 | 47 | 42 | Confidential (fermentation process) | ||||
gamma-Octalactone | 4 | 1 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7 | |||||||
Tropicalone | 5 | 0 | 10 | 2 | 1 | 6 | 1 | 4 | 0 | 44 | 1 | 73 |
The environmental hotspots of raw materials derived from cultivated plants are linked to the land use. The mechanization of the cultivation leads to an important contribution to climate change (linked to the diesel necessary for tractors and agricultural machinery and to fertilizers). Eutrophication increases too, linked to fertilizers applied on agricultural soils. Human toxicity becomes a hot topic as well due to the direct Zinc emission to soil from tires abrasion. Because of its high uncertainty, particularly regarding heavy metals, the contribution of human toxicity on SPOT single score is highlighted in graphs.
For ingredients like Elemi EO and Pink Pepper Pure Jungle Essence ™, made with a wild harvested biomass, raw material production is not an environmental issue. Indeed, no land use, no mechanization nor use of pesticides or fertilizers are associated to these raw materials, leading to very small impacts measurable via an LCA. Other life cycle steps contribute nevertheless to the single score, like the incineration of biowaste (Elemi essential oil).
For ingredients coming from fossil raw materials, the environmental hotspots are climate change and ecotoxicity due to the production of the starting materials.
Fig. 3 Contributors of impact of the production of 1 kg of centifolia rose petals on SPOT single score (mPt). |
Secondly, to investigate the potential influence of different raw material origin on the overall environmental impact of a renewable sourced ingredient, two sourcing of Myrcene were compared: one from crude sulfate terpentine (CST), a co-product of paper pulp production, and the other from pine.
The downstream transformation steps are the same, and only the raw material vary. Fig. 4 shows that the global SPOT score varies significantly with Myrcene from CST having a score 2 times higher than Myrcene from pine. Indeed, the former possesses a part of the burdens of kraft pulp production whereas the latter comes free of burdens for its raw material since pine essence is collected by hand from the tree.
Fig. 4 Contributors of impact for Myrcene from crude sulfate turpentine and pine on the SPOT single score (μPt). |
However, because of different overall yield of extraction process from the raw material, the downstream transformation varies in absolute impact value and is higher in the case of Myrcene from pine.
Finally, to compare an ingredient between fossil and renewable resources, cis-3-Hexenol environmental impact was investigated. As shown in Table 9, the cis-3-Hexenol from a renewable source (Mint leaves) has a greater impact than the fossil-based one by an order of magnitude of 100. This huge gap is predominantly due to mint essential oil containing a very small quantity of the desired ingredient (traces to 0.15%).48 This leads to a very low yield (0.001%) and a large consumption of mint leaves and energy for the hydrodistillation. Co-products are generated and valorized (menthol, terpenes such as α-pinene, β-pinene, limonene, etc.), but with less economic value than cis-3-Hexenol. Mint leaves are reused as biomass for energy production. Compared to a two-step synthesis from readily available chemicals (butadiene and formaldehyde), the cis-3-Hexenol from a renewable source has a much higher environmental impact.
Origin | Irrigation | Electricity & infrastructures | Upstream transport | Raw material | Waste | Solvent | Total |
---|---|---|---|---|---|---|---|
Renewable | With | 1.846 | 0.088 | 59808 | 3.794 | 0 | 65536 |
Without | 1.846 | 0.088 | 47304 | 3.794 | 0 | 53033 | |
Fossil | — | 0.254 | 0.016 | 0.165 | 0.198 | 3 × 10−3 | 0.636 |
The culture of mint leaves being the major contributor for the renewable sourced cis-3-Hexenol, its farming practices are the main source of potential eco-design. Mint leaves suppliers of MANE are in a humid region of India which allow them to cultivate with reduced irrigation. With the assumption of an identical harvest yield, this practice leads to a decrease of 24% of the SPOT single score compared to an irrigated culture.
This comparison of renewable and fossil origin for a fragrance ingredient highlights the fact that renewable origin does not always means lower environmental impact. A more in-depth analysis, including important parameters such as yield, potential co-products, agricultural practices, is always needed to identify the environmental issues of both types of sourcing and to determine the less impacting one for a given ingredient.
As Table 10 shows and as LCA did, GREEN MOTION™ evaluation of fragrance ingredients also reveal some significant variance between and within categories but not for all of them. Overall, the toxicity appears to be the biggest contributor, with only some ingredients of the Essentials oils (EO) and Jungle Essence™ extracts category and the Essences by expression where it does not contribute much. This is a main point of difference between GREEN MOTION™ and SPOT since the latter, through LCA, does not capture well health hazards linked to dangerous substances manipulation. Following toxicity, the other biggest contributors are raw material and waste impact E-factor, but only for Fossil-based ingredients (and to some extent Bio-based with a fossil-based moiety ones) and Absolutes ingredients respectively. This is explained by the fact that using fossil-based chemicals is severely penalized in GREEN MOTION™. For Absolutes ingredients, it comes from the fact that their production requires a lot of biomasses, which then need to be disposed, and which explains the relative high contribution of the reaction efficiency concept. Solvent, reaction efficiency and energy consumption all contribute to the same degree overall, except for Essentials oils (EO) and Jungle Essence™ extracts where it depends on the ingredient. Finally, the final product impact is usually not a hotspot except for a few specific ingredients.
Fig. 5 SPOT single score and GREEN MOTION™ impact scores of “Essential oils and Jungle Essence™ extracts” ingredients. |
In contrast, Jungle Essence™ extracts ingredients have higher impacts with GREEN MOTION™ than other ingredients of the same category but not with SPOT. GREEN MOTION™ considers energy consumption and security aspects of pressurized gas manipulation whereas SPOT does not, as specific data were not available to model the pressurization and as security aspects are not (yet) taken into account in LCA.
Fig. 6 SPOT single score and GREEN MOTION™ impact scores of “Natural extracts with solvent – Absolutes” ingredients. |
Fig. 7 SPOT single score and GREEN MOTION™ impact scores of “Natural extracts with solvent – Resinoids” ingredients. |
Fig. 8 SPOT single score and GREEN MOTION™ impact scores of “Bio-based with a fossil-based moiety” ingredients. |
Ingredient category | Main(s) hotspot(s) | Eco-design levers |
---|---|---|
Essentials oils (EO) and Jungle Essence™ extracts | Raw material | Yield of culture or extraction |
More sustainable farming practices | ||
More co-products valorization | ||
Essences by expression | Raw material | Yield of culture |
More sustainable farming practices | ||
Natural extracts with volatile solvent – Absolutes | Raw material and transformation process | Yield of culture |
More sustainable farming practices | ||
More biowaste valorization | ||
More efficient extraction processes (yield and energy use) | ||
Natural extracts with volatile solvent – Resinoids | Solvent | Use of more environmentally friendly and less toxic solvents |
Isolated natural ingredients | Raw material | Yield of culture |
More sustainable farming practices | ||
More co-products valorization | ||
Bio-based ingredients with a fossil-based moiety | Solvent | More sustainable farming practices |
More biowaste valorization | ||
Yield of manufacturing | ||
More efficient extraction processes (yield and energy use) | ||
Chemical synthesis optimization (C factor for example15) | ||
Fossil-based ingredients | Raw material and transformation process | Yield of manufacturing |
More efficient extraction processes (yield and energy use) | ||
Chemical synthesis optimization (C factor for example15) | ||
Biotechnology ingredients | Confidential | Yield of manufacturing |
More efficient processes (energy use and downstream processes) | ||
Optimization of solvent use |
For ingredients from renewable sources, upstream agriculture represents a large part of the environmental burdens (30–100%), the degree depending on the combination of the magnitude of the inputs required for the culture and the type of processing steps they involve: 65–100% when hydrodistillation are conducted, 30–98% when solvent extraction are performed or 31–66% when chemical syntheses are used. Plant cultivations are modeled with a varying level of precision and reliability, from generic databases based on average data (vanilla beans and orange fruit production) to specific data directly coming from the plant producer (all the other ingredients). Using only specific data could potentially change some results of this study. Furthermore, agricultural activities modeling requires a lot of data to overcome potential variability from year to year due to changing climate conditions and plant diseases. To the best of author's knowledge, specific data collected for this study were estimated as average data over several years based on suppliers and farmers experience. Nonetheless, measured data over a longer period would increase the robustness of the results.
Therefore, knowledge on agricultural sector and its practices is of utmost importance to determine the real environmental impact of a given ingredient and to reduce it, along with the overall manufacturing yield (0.01–99.9%). This last parameter acts as a magnifying glass of all upstream impacts, and heavily influences the energy, biomass and solvent quantities needed. Improving the culture yield is important (0.3–30 t ha−1), but it must not be at all costs.
More sustainable supply chains, established in adapted environment, is an efficient way to reduce the impact of renewable-sourced ingredients (see cis-3-Hexenol case). However, alternative agriculture systems, such as organic farming and agroecological systems, are still misrepresented in LCA54 and further methodological developments are needed to better capture the potential related benefits in LCA.55,56 Wild plants harvested by hand could be seen as a solution since it is usually considered without impact in LCA, but careful evaluation is needed to avoid potential natural resources overexploitation and biodiversity impacts. The valorization of co-products and the development of a potential circular economy are key levers to lower the environmental impacts of fragrance ingredients. In this regard, biowaste of such processes (0–600 kg kg−1 of product) is a major source of potential raw material to be valorized in a circular economy.57
Concerning fossil-based ingredients, the wide variety of environmental profiles comes from the difference in the number and complexity of synthesis stages. Knowing the full production process is thus important to evaluate their impact with good reliability and eco-design their chemical synthesis pathway. However, it is not a trivial task when such substances are produced by different manufacturers along the supply chain. Ingredients evaluated in this study involve relatively simple and/or known processes which could be modelled based on reliable data and assumptions. However, the synthetic pathway and/or missing specific data (e.g. solvents, catalysts, energy, etc.) could help to refine the environmental profile since their contribution may be significant (see Table 8).
LCA is a powerful tool to analyze environmental issues but is a very data intensive method. Although the amount and quality of data available for this study was high, knowledge on materials bought from suppliers is always weaker, which forces to make assumptions. Even for substances produced in-house, specific data for a specific process cannot always be obtained and often consumption data are annualized at the plant level. For example, overconsumption of energy for CO2 pressurization could not be quantified and attributed to the Jungle Essence™ extracts. A sensitivity analysis was conducted with Vanilla Pure Jungle Essence™ ingredient. When replacing MANE's data on energy and water consumption with an adapted supercritical CO2 process from decaffeination of green coffee inventory from the WFLDB,41 the single score increased by around 11%. This suggests that the supercritical CO2 consumption is a key parameter of the fragrance ingredient environmental performance and should be assessed more in details in following studies to improve the modeling and the environmental profile assessment of this category of ingredients.
Comparison of the LCA results with the green chemistry-based tool GREEN MOTION™ leads to similar tendencies overall. Some differences on specific aspects can be explained by the fact that LCA/SPOT and GREEN MOTION™ consider the whole life cycle but different parts are integrated in different manners: the former quantifies all inputs and outputs of the inventory whereas the latter integrates qualitatively or semi-quantitatively some parameters of LCA (yield, waste generated, etc.) and some not usually integrated in LCA such as safety aspects.
The 2 tools can nevertheless be complementary in the aim of evaluating the environmental profile of fragrance ingredients. Detailed results and knowledge about the environmental hotspots of the ingredients over their upstream life cycle can be gained with SPOT single scores based on LCA. However, such analysis is time and data-consuming, which limits its ease of realization. Thus, when one wishes to evaluate a range of ingredients and implement eco-design practices, GREEN MOTION™ appears to be a suitable tool. Indeed, easy to implement on a large scale, it works with a lower number of selected criteria derived from green chemistry principles. For that reason, GREEN MOTION™ method tends to deliver higher impacts for ingredients that requires a lot of hazardous chemicals in their process production, no matter the amount needed. In a conservative approach, this allows to compensate for the lack of some environmental and health issues not well covered in LCA studies, such as the dangerousness of manipulating toxic substances. However, one important limit of GREEN MOTION™ method is that it does not capture the upstream agriculture potential environmental issues for renewable raw materials and that subject should be dealt in parallel to avoid impact displacement during eco-design processes.
Finally, the E-factor is a simple metric to gauge the mode of production of fragrance ingredients, which can help in a first approach to design more efficient processes, requiring less resources and generating less waste. The reality of the assumed benefits for the environment must nevertheless be checked in a second step, as indirect impacts may be linked to catalysts, solvents, raw materials production or to an overconsumption of energy or water.
These 3 tools can be used in complementary during innovation processes. When a new project starts, metrics like E-factor are helpful tools to steer innovation in the right direction to reduce potential environmental impacts. When a concept becomes mature enough, GREEN MOTION™-like tools allow to eco-design it. Finally, when the innovation is about to be settled, a full LCA can be used to confirm or infirm the environmental benefits of the innovation.
Indeed, currently in LCA, fossil-based and bio-based substances can have an overall similar environmental impact, albeit different depending on the indicators.58 Nonetheless, renewable sources could be an efficient way to tackle resources depletion and greenhouse gases. However, this is highly dependent on the type of culture implemented as agriculture is often mechanized and uses diesel for agricultural machinery, (chemical) fertilizers and pesticides. To overcome this challenge, several eco-design practices can be implemented to reduce the overall environmental impact of bio-based ingredients.59 Among the possible actions, more sustainable and adapted culture of starting biomasses60 and more efficient extraction/transformation processes would lead to the biggest improvements. Alternatively, more valorization of co-products and biowaste in a circular economy philosophy could also drastically reduce environmental burdens.
Following green chemistry principles and using dedicated tools such as GREEN MOTION™ will allow in a first step to focus the eco-design on the last steps of the production process of fragrance ingredients. These tools can lead to efficient reduction of environmental burdens of fragrance ingredients. In a second step, LCA can be conducted to measure in an exhaustive way all the potential environmental impacts of the whole life cycle, identify hotspots and validate improvements after implementation of eco-design practices. This is particularly important for hotspots in the upstream value chain.
The results presented in this study are a first step towards a clustering method of ingredients composing fragrances, that could be developed to help conducting a LCA and assess globally the environmental impact of any complex fragrance compositions while respecting the confidentiality of the formula. Indeed, ingredients could be grouped in relevant clusters, depending on their production process and on their starting raw material, as demonstrated here. Then, the environmental LCA profile of a fragrance would be estimated based on its quantitative composition in each ingredient cluster, without disclosing the exact composition of the formula. As knowledge is gained on ingredients, data quality of ingredients categories will improve, leading to an improvement of the environmental evaluation of fragrances. This first clustering approach paves also the way for future sub-clusters developments and subsequent improvements.
Footnote |
† Electronic supplementary information (ESI) available. See DOI: https://doi.org/10.1039/d2gc04860d |
This journal is © The Royal Society of Chemistry 2023 |