Page 42 - Materials Chemistry, Second Edition

L1644_C01.fm Page 18 Monday, October 20, 2003 11:46 AM

1.5.4.1 Life-Cycle Assessment (LCA)

In order to consider environmental impacts of a product’s life-cycle systematically,
the life-cycle assessment (LCA) methodology has been developed. This is the only
standardized tool currently used to assess product environmental loads. The steps
of LCA are: goal and scope definition, inventory analysis, impact assessment, and
interpretation.
The goal, the motivation for research, must be clearly defined from the very
beginning because the following phases will be influenced by its early definition.
The creation of life-cycle inventories (LCIs) is intended to identify and assess the
environmental load associated with the full life-cycle of a product, process or activity.
In the case of a product, the inventory starts at the extraction process of raw materials
from the environment, continues in the production, consumption and use of end
products, and ends when the product or its derivate turns into waste. Operations
such as transportation, recycling, maintenance, etc. must also be considered in the
inventory.
Life-cycle impact assessment (LCIA) allows for easier interpretation of envi-
ronmental information produced during the inventory analysis phase. LCIA includes
several phases:

• Classification of environmental loads within the different categories of
environmental impact
• Categorization of environmental loads by means of a reference pollutant
typical of each environmental impact category
• Normalization of the data obtained from the characterization, dividing it
into real or foreseen magnitude for its corresponding impact category
within a geographical location and a point in time for reference
• Quantitative or qualitative assessment of the relative significance concern-
ing different categories of impacts

These categories, plus the level of detail and methodology, are chosen depending
on the goals and scope of the research.
Following this analysis, more objective and transparent decisions can be made
concerning environmental management for the creation of guidelines for new product
development and guidebooks to define environmental priorities (SETAC, 1993). See
Chapters 2 and 3 for more details.

1.5.4.2 Environmental Risk Assessment (ERA)

The usual point in introducing risk assessment is to emphasize that risk is part of
everything we do and that the risk derived from pollutant exposure should be paid
the attention it deserves. In the U.S. during the late 1980s, about 460,000 of 2.1
million deaths per year were due to cancer. Without taking the age factor into
consideration, the risk of dying from cancer equals 22% (460,000/2,100,000 = 0.22).
Individuals who smoke one package of cigarettes per day have approximately a 25%
risk of dying from heart disease. Meanwhile, the U.S. Environmental Protection

© 2004 CRC Press LLC