The whys and wherefores of life-cycle assessment

By Catherine Watkins

In This Section

May 2017

  • Life-cycle assessment (LCA) is a tool used by organizations of all sizes to analyze the overall environmental impact of their products, processes, and services.
  • LCA can advance product and process innovation as well as enhance competitive differentiation among brands. It can also be used to identify cost-savings, improve design decisions, and achieve regulatory mandates.
  • If your organization isn’t currently performing LCAs, you can be sure your competitors are doing them on your products.

Life-cycle assessment, or LCA, is a tool for quantifying the overall environmental impact of products and processes, from the extraction of raw materials through to product disposal, or from “cradle to grave.” Industry pioneered development of this analytical methodology beginning in the 1960s; the International Organization for Standardization (ISO) has since codified the methodology into a suite of standards (see sidebar article).

“LCAs can be an important tool in building a company’s business by identifying cost-saving opportunities, such as on energy and water, or by building gross sales or revenue by helping identify new environmentally sustainable products,” says Len Sauers. Sauers, who retired in 2016 as vice president of global sustainability for P&G in Cincinnati, Ohio, USA, currently consults on corporate sustainability strategy through LJS Consulting LLC (also in Cincinnati).

Industry takes the lead

Former AOCS President Erich Dumelin, who retired from Unilever in 2007 as vice president, supply chain strategy and technology for the company’s food business, remembers the early days of LCA development.

In the 1980s, he says, Unilever Switzerland began examining the environmental impact of product packaging using Ecopro software from EMPA (the Swiss Federal Laboratories for Materials Science and Technology in St. Gallen).

“As far as I know, this was the first institution to develop a program to assess the impact of industrial activities on the environment, starting with packaging material,” Dumelin notes. “Later, during my time at the Unilever Center in the 1990s, the first talks about CSR (corporate social responsibility) began on a much broader level, and we became more aware and concerned about the global impact of our products and services.”

One of Unilever’s initial ideas was to choose more sustainable product packaging materials, product formulations, and technologies, according to Dumelin. “The ability to choose alternative materials and processes to produce ‘greener’ products was often constrained by other factors. These included the nutritive value, product functionality, sensory qualities, and cost. Therefore, our emphasis shifted from replacement with ‘cleaner’ alternatives to improving the environmental footprint of the raw materials and processes. For the assessment of the environmental aspects of our sustainability efforts, the LCA tool came in handy and today is probably the method of choice,” he concludes.

Dumelin notes that following the complete edible product supply chain from cradle to fork, including disposal, revealed that the environmental impact of the raw materials was usually much greater than the sum of what followed further down the chain. It also became clear that consumer behavior and preference could have a significant effect on the upstream environmental impact of a product.

“Evaluation of products or processes for environmental impact was done for decades before it was called life-cycle assessment,” explains Len Sauers, adding that P&G was also an early pioneer in LCA development.

LCAs sometimes return surprising results that run counter to a company’s assumptions, he says. A classic example is the comprehensive LCA P&G conducted in 2008, which looked at energy use and greenhouse gas (GHG) emissions for all the company’s product categories. Before conducting the LCA, P&G researchers intuitively assumed the greatest environmental impact of its detergent products would relate to manufacturing.

“We found that the greatest use of energy and largest emissions of GHG came from the consumer-use phase of laundry detergents,” Sauers noted in an email. “More specifically, it came from the heating of water to do laundry. This information formed the basis for a research program into the development of new technologies that improve the performance of laundry detergents in cold water. A new product was introduced—Tide Cold Water. The technologies were also used to improve the performance of our premium brands. We also set a corporate environmental sustainability goal of having 70% of machine loads washed in cold water by 2020.”

The basics of LCA

The methodology for conducting LCAs is contained in a set of standards from the International Organization for Standardization (ISO; see sidebar article). These include full assessments (ISO 14044–14073) as well as streamlined analyses (ISO 14064–14067 and ISO 14069).

In brief, full LCAs comprise four repeating steps: 1) defining the goal and scope of the study, 2) completing a Life-Cycle Inventory (LCI), 3) performing a Life-Cycle Impact Assessment (LCIA), and 4) interpreting the results. As each step is completed, the results of that step are validated against the preceding steps for accuracy and adherence to the original objectives of the study (see Figure 1).

Figure 1

FIG. 1. Methodological framework for life-cycle assessment (ISO 14040 and 14044). This figure visualizes the iterative flow of information in the LCA process. Source: American Center for Life Cycle Assessment (Washington, DC, USA;

The goal and scope of the assessment must be stated explicitly, including defining the functional unit, the system boundaries, the assumptions and the limitations of the study, the impact categories, and the methods used to allocate environmental burdens.

The LCI phase examines all the inputs and outputs in the product’s life cycle, beginning with raw material extraction and extending through manufacture to the consumer-use phase and, finally, through to disposal (or recycling) of the product and/or packaging.

Next, the life-cycle impact assessment translates the LCI results into environmental impacts. These can be assessed at either the midpoint—for example, water use, eutrophication or land use—or endpoint levels such as the impact on human health, resource depletion or ecosystem quality.

The final interpretation phase identifies, quantifies, and evaluates information from the results of the LCI and LCIA. It should result in a set of conclusions and recommendations, and in order to comply with ISO 14040 (2006) and ISO 14044 (2006) standards, the LCA must be critically reviewed by a panel, with the results made available to the public.

“In theory, concepts of LCA can be applied to any value chain that involves any kind of material, energy, packaging, processes, products, technologies, processes, or services,” explains Bill Flanagan, director of the Ecoassessment Center of Excellence at GE in Niskayuna, New York, USA. Flanagan also is chair of the board of directors of the American Center for Life Cycle Assessment, a non-for-profit membership organization based in Washington, DC, USA.

Comparing different products or technologies on a functionally equivalent basis can provide strategic insights and potentially even lead to changes in a company’s business model, he says. For example, a company that sells music on compact disc determines through an LCA that it is more advantageous to offer music via download or online streaming.

Caveats and conundrums

So, just how robust is the LCA methodology?

“Data are crucial to LCAs, and LCAs are not hard science,” notes one source, who asked to remain anonymous. “The input and output data need to be selected as consistently and stringently as possible, and that may often be difficult. Nevertheless, LCAs can provide guidelines for policy makers and other interested parties as long as their potential shortcomings are recognized.”

Thomas P. Gloria, director of sustainability at the Harvard Extension School (Cambridge, Massachusetts, USA) and managing director of Industrial Ecology Consultants (Newton, USA) agrees with this view.

“Datasets can be small in sample size and may not be truly representative,” he says. “If it is a critical item in your analysis, you need to check, recheck, and understand the uncertainties and variability associated with datasets, which generally are not well characterized. LCA is a wonderful tool, but there are other methodologies that might be more appropriate at a regional or site-specific level.”

Gloria also counsels that interpretation of LCA results is subjective and, therefore, can lead to difficulties in decision-making. If the results show an increase in environmental impact in one category and a decrease in another, “a value judgment needs to be made.” He emphasizes that “the LCA methodology provides the awareness and transparency to show where the science ends and a value judgment is made.”

Despite the caveats, LCA “is the way you should think in considering the whole of what you are doing,” says Gloria. “The problems in the world are becoming more and more complex, which makes holistic, multidimensional tools such as LCA not just preferred, but essential.”

Catherine Watkins is a freelance writer based in Champaign, Illinois, USA. She may be reached at

Oils heated at 150°C for 20 days. Photo courtesy of DuPont Pioneer.
Oils heated at 150°C for 20 days. Photo courtesy of DuPont Pioneer.


LCA of high-oleic soybean oil used for restaurant frying

Oils heated at 150°C for 20 days. Photo courtesy of DuPont Pioneer.

DuPont Pioneer used attributional life-cycle methodology to quantify the environmental impacts of and identify supply chain hotspots for high-oleic soybean oil (HOSO), conventional soybean oil (CSO), hydrogenated soybean oil (HSO), high-oleic canola oil (HOCO), and conventional canola oil (CCO). (Attributional LCA describes the environmentally relevant physical flows to and from a product or process, whereas consequential LCA analyzes how relevant environmental flows will change in response to possible decisions.)

Two scenarios were used in the study. The first assumed two days of fryer use with a 4% loss rate of oil to the food per day and the second assumed six days of fryer use and a 10% loss rate of oil to the food per day. The system boundaries included agricultural inputs, farming operations, seed processing, soybean and canola oil refining (and hydrogenation, when applicable), transport along the supply chain and of the refined oil to a warehouse near the restaurant, oil use in the restaurant, washing of the fryers, and spent oil disposal.

Results of the study indicated that across all impact categories, the increased oil stability of the high-oleic oils and HSO resulted in roughly a 30–45% reduction in impact relative to conventional oils. The impact categories used for this study were climate change potential, eutrophication potential, acidification potential, land use, and nonrenewable energy demand.

“The large majority of food companies understand high-oleic oils and the value they bring in terms of oxidative stability and function,” noted Susan Knowlton, senior research manager at DuPont Pioneer. “They don’t, however, understand the environmental impact. This LCA helped us to educate people downstream about how oils from Plenish high-oleic soybeans can be used to lower the environmental impact of frying oils in the restaurant setting.”

“Environmental Life-Cycle Impacts of High Oleic Soybean Oil Used for Frying,” Todd M. Krieger and Susan Knowlton, Proceedings of the 9th International Conference on Life Cycle Assessment in the Agri-Food Sector, October 2014. This article is available for download at


The American Center for Life Cycle Assessment (ACLCA; Washington, DC, USA; is a nonprofit membership organization providing education, awareness, advocacy, and communications to build capacity and knowledge of environmental LCA. ACLCA membership is drawn from industry, academia, government, consulting, and nongovernmental organizations. ACLCA includes both domestic and international members.

The Life Cycle Initiative ( is a joint activity of the United Nations Environment Programs and the Society of Environmental Toxicology and Chemistry (SETAC; The objective of the Life Cycle Initiative is to “facilitate the generation and uptake of science-based life cycle approaches and information for products by business, government, and civil society practice worldwide as a basis for sustainable consumption and production.” As such, the Initiative advocates Life-Cycle Sustainability Assessments (LCSA), which extend LCAs in order to evaluate all environmental, social, and economic impacts of product life cycles. A number of reports on LCSAs are available at

Environmental Product Declarations
Customers and consumers alike increasingly demand information about product sustainability before they make buying decisions.

One advantage of conducting an ISO-compliant LCA is that one can then apply for an independently verified and registered document known as an Environmental Product Declaration (EPD; ISO 14025). EPDs are much like nutrition labels; they simply disclose the environmental impacts of a product rather than certifying that the product itself is “green.” Visit to view a sample EPD document for Castillo de Canena extra virgin olive oil. Search among all EPDs registered within the International EPD® System, or browse the database by product category at

LCI databases
The most comprehensive commercially available databases for life-cycle inventories, according to Bill Flanagan of the ACLCA, are ecoinvent and GaBi. The former is available by license at from a not-for-profit association founded by the institutes of the ETH Domain and the Swiss Federal Offices. The latter is available from thinkstep (Echterdingen, Germany) at An interactive map of databases is available at

Published LCAs
“Comparison of oleo- vs. petro-sourcing of fatty alcohols via cradle-to-gate life-cycle assessment,” Journal of Surfactant and Detergents (2016),

This LCA found petro-based fatty alcohols had overall lower average greenhouse gas emissions compared to palm kernel oil (PKO)-based fatty alcohols. “We found the judicious decisions on land use change, effluent treatment and solid waste treatment are key to making PKO-FA environmentally sustainable,” according to the article’s abstract.

“Life-cycle assessment of five vegetable oils,” Journal of Cleaner Production (2015),

Researchers conducted a consequential LCA of palm, peanut, rapeseed, soybean, and sunflower oils, focusing on global warming, land use, and water consumption. “With respect to global warming, rapeseed oil and sunflower oil are the best performing, followed by soybean oil and palm oil, and with peanut oil as the least good performing. For land use, palm oil and soybean oil are the oils associated with the smallest contribution, followed by rapeseed oil, and with sunflower oil and peanut oil as the oils with the largest net occupation of land. When focusing on water consumption (using the water stress index), sunflower oil had the smallest impact, followed by rapeseed oil, palm oil and soybean oil, and with peanut oil as the oil with the largest contribution.”

“Potential of biofuels from algae: comparison with fossil fuels, ethanol and biodiesel in europe and brazil through life-cycle assessment,” Renewable and Sustainable Energy Reviews (2017),

ISO LCA standards
ISO—the International Organization for Standardization—has developed a suite of nine standards relating to life-cycle assessment, which are available for purchase at These standards cover the assessment of impacts on the environment from the extraction of raw materials (cradle) to the final disposal of waste (grave). Note that two additional LCA standards are under development by ISO Technical Committee 207/Subcommittee 5 (ISO 14044:2006/DAmd 1 and ISO PRF TR 14073).

In addition, standards for streamlined LCAs looking only at quantification and validation/verification of greenhouse gas emissions, including calculating the carbon footprint of products, are available (ISO 14064–14067 and ISO 14069).

Following are the standards pertaining to full LCAs.

  • ISO 14040:2006 (Ed. 2)
    Environmental management—Life cycle assessment—Principles and framework
  • ISO 14044:2006 (Ed. 1)
    Environmental management—Life cycle assessment—Requirements and guidelines
  • ISO 14045:2012 (Ed. 1)
    Environmental management—Eco-efficiency assessment of product systems—Principles, requirements and guidelines
  • ISO 14046:2014 (Ed. 1)
    Environmental management—Water footprint—Principles, requirements and guidelines
  • ISO/TR 14047:2012 (Ed. 2)
    Environmental management—Life cycle assessment—Illustrative examples on how to apply ISO 14044 to impact assessment situations
  • ISO/TS 14048:2002 (Ed. 1)
    Environmental management—Life cycle assessment—Data documentation format
  • ISO/TR 14049:2012 (Ed. 2)
    Environmental management—Life cycle assessment—Illustrative examples on how to apply ISO 14044 to goal and scope definition and inventory analysis
  • ISO/TS 14071:2014 (Ed. 1)
    Environmental management—Life cycle assessment—Critical review processes and reviewer competencies: Additional requirements and guidelines to ISO 14044:2006
  • ISO/TS 14072:2014 (Ed. 1)
    Environmental management—Life cycle assessment—Requirements and guidelines for organizational life-cycle assessment
  • ISO/DTR 14073
    Environmental management—Water footprint—Illustrative examples on how to apply ISO 14046