The life cycle analysis (LCA) method quantifies the environmental impacts of a given product. In LCA, researchers compile a list of the resources and pollutants produced during product production and use. An impact assessment is derived from this to estimate the product's ultimate effects on human health, ecosystem function, and natural resource depletion. LCA method standardization has sought to maintain flexibility while ensuring consistency and clarity in reporting. LCA has been used to estimate the net effects of various biofuels, including corn ethanol, on petroleum use, climate change, air, and water quality, and other impact categories.