Life Cycle Assessment (LCA) is a technique developed to measure the possible environmental impacts caused as a result of the manufacture, use and disposal of a particular product or service. The life cycle refers to all stages of production and use of the product, from extraction of raw materials extraction to production, distribution, consumption and final disposal (even in the case of recycling and/or reuse).

Blind reading:
Quantitative and multicriteria methodology.
The first study classified as LCA was commissioned by Coca-Cola in the US in 1969.
Purpose: understanding costs and impacts of life-cycle standards of packaging made of different types of materials (plastic PET and glass reusable bottles).
Method: observing the inventory of raw materials, the use of fuel and environmental loads in the manufacturing processes.
Legacy: The study is known as Resource and Environmental Profile Analysis (REPA) and was widely disseminated.
Origin: EIO-LCA, the economic input-output life cycle assessment methodology, is based on work with input-output matrices from the 30’s.
LCA studies are determined by the ISO 14040 standard.
There are four major phases observed: goal and scope, inventory analysis, impact assessment and interpretation.
Goal and Scope
Definition of the boundaries of the study (temporal and geographical), to whom the results are intended to, quality criteria and impact categories to be considered.
Inventory Analysis
Collection of data representing the flows of matter and energy entering and exiting the several stages of the product life cycle. This step may include fieldwork with primary data collection or include collection of literature data (secondary data).
Impact Assessment
Software with high data processing capacity is used. They assist experts in “translating” the life cycle model created to reflect the product or service under analysis in environmental impact indicators.
[Highlight: Here are the impact categories not commonly communicated, such as eutrophication, for example.]
[Highlights: One of the most well-known indicators is kg of CO2 for the global warming category.]
Interpretation
Identification of the study’s significant issues, integrity check, sensitivity and consistency of results and definition of conclusions, limitations and recommendations of the study. The interpretation must occur throughout the study and not only in the final stage: such architecture usually does not provide a linear study throughout the phases.
Impact categories assessed (examples):
– Global Warming Potential (GWP) → Global warming
– Ozone Depletion Potential (ODP) → Ozone depletion
– Photochemical Ozone Creation Potential (POCP) → Photochemical ozone creation
– Acidification Potential (AP) → Acidification
– Eutrophication Potential (EP) → Eutrophication
– Eco and Human Toxicity Assessment → Eco and human toxicity
– Consumptive Water Footprint and Water Emissions Footprint → Water footprint
– Direct land use change (LUC) and Indirect land use change (ILUC) → Land use change
The main production, use and disposal steps assessed by LCA:
1 – Extraction and processing of raw materials
This step in the production chain has direct contact with the environment and most of its environmental impacts are related to the depletion of nonrenewable resources, emissions of polluting gases and use of water.
2 – Manufacturing
The impacts of this step are generally related to industrial processes usually associated with high energy consumption, water and atmospheric emissions.
3 – Packaging
The environmental impact of ground transport has an impact on land use and atmospheric emissions due to the use of energy/fuel combustion, as well as water and air transport.
4 – Marketing and Transformation Industry
Usually, transformation is the time when the end product is developed and where design is essential to create product and context inducing a more sustainable life cycle, such as the increase of its durability and recycling potential. In this step, a lot of raw material and energy are required.
5 – Use, reuse, and recycling
Positive and negative impacts are accounted for when the product or service is being used by the final consumer. Plastic, for example, can reduce food waste, in the form of packaging, or reduce the energy expenditure of cars and airplanes, when used as an industrial part (lighter than those produced with metals).
6 – Safe disposal and waste
Disposal can have a negative or positive environmental impact. If the disposal procedure is correct, materials can be reused or recycled for various applications. If it’s incorrect, materials may contaminate the air, soil, and rivers or oceans.
Countries where LCA is used for public policies:
Germany (recycling)
Chile (biofuels)
United States (biofuels)
France (industry)
Mexico (biofuels)
Peru (biofuels)
In Brazil, academic research on LCA is more common in the following sectors:
Livestock and Agriculture
Automotive
Construction
Packaging
Energy
Chemical industry
Mining
LCA application: Austin case (Texas, USA)
A study about LCA to assess the ban on disposable plastic bags → population migrated to durable plastic bags with greater energy footprint → these bags, over time, became disposable, but produced more energy and water impact with less recycling efficiency.
Application of LCA: diaper case
Durable cloth diapers: lower generation of solid waste, higher generation of effluents
Disposable diapers: smaller water footprint, greater generation of solid waste
Conclusion: the most appropriate use depends on local environmental conditions and consumer behavior. Consumer behaviors such as hot washing, ironing or machine-drying, strongly influence the environmental impact of cloth diapers.
Sources:
Brazilian Association of Life Cycle (ABCV – Associação Brasileira de Ciclo de Vida)
Brazilian Institute of Science and Technology Information (IBICT – Instituto Brasileiro de Informação em Ciência e Tecnologia)
Institute of Applied Economic Research (IPEA – Instituto de Pesquisa Econômica Aplicada)
Brazilian Association of Technical Standards (ABNT – Associação Brasileira de Normas Técnicas)
The International Journal of Life Cycle Assessment
Content published in June 14, 2019