LCA

LCA, or Life Cycle Assessment, is a systematic method for evaluating the environmental aspects and potential impacts of a product, process, or service across its entire life cycle. The goal is to identify where environmental burdens arise and to support decision making that reduces overall impact, from design to end of use.

It follows four phases defined in international standards: goal and scope definition; life cycle inventory (LCI) in which material and energy inputs and environmental releases are collected; life cycle impact assessment (LCIA) in which those flows are translated into potential environmental impacts; and interpretation to draw conclusions and suggest improvements. Central concepts include the functional unit, which provides the basis for comparison (for example, one liter of beverage or one kilogram of product), and system boundaries, which define cradle-to-grave, cradle-to-gate, or other cut-off criteria.

LCIA typically aggregates emissions and resource use into impact categories, such as climate change (global warming potential), ozone depletion, acidification, eutrophication, photochemical smog, and resource depletion. Some LCAs use midpoint indicators; others use endpoint indicators that relate to potential damage to humans or ecosystems. Data are drawn from life cycle inventory databases and, when possible, site-specific measurements; uncertainty and data quality are key considerations.

Standards guiding LCA include ISO 14040 and ISO 14044, with emerging guidance for water footprints under ISO 14046. LCAs inform product design, procurement, policy analysis, environmental labeling, and corporate sustainability reporting, enabling comparisons of alternatives and identification of hot spots for improvement.

Limitations include data availability and quality, allocation choices when inputs or outputs are co-produced, geographic and temporal specificity, and methodological complexity. Despite these caveats, LCA remains a widely used tool for understanding and reducing environmental impacts of products and systems.