Assessment can't replace life-cycle thinking

As the packaging industry increasingly engages in discussions of metrics and scorecards to assess environmental performance, it is important to distinguish between two terms: Life Cycle Thinking and Life Cycle Assessment.

Life Cycle Thinking is a qualitative framework used to understand and assess systems. It has historically been applied to natural systems through fields like ecology, where we study the relationships between species and their habitats. More recently, in the field of industrial ecology, we have applied the framework of Life Cycle Thinking to industrial systems as a way to understand man-made systems and their interaction with the natural environment.

Often, in an industrial context, Life Cycle Thinking is used to ask: “What are the systemic impacts of an industrial action or process? If I take a certain action, what are the resulting consequences throughout the supply chain and beyond to natural systems?” Because natural and man-made systems are inseparable, this is a challenging question. Life Cycle Thinking doesn't produce easy answers, but it does provide a framework to recognize and understand these complex systems and their interrelationships.

Life Cycle Assessment is rather a quantitative tool used to develop partial answers to the questions posed by Life Cycle Thinking. We use Life Cycle Aassessment to measure the known burdens our industrial processes impose on various environmental impacts like greenhouse gas emissions, water consumption, etc. But Life Cycle Assessment has significant limitations.

It can only be used where inventory data and accepted Life Cycle Impact Assessment (LCIA) methods exist. When either of these is missing, it's not a useful tool. For example, Life Cycle Thinking might help discover that packaging debris is creating problems for marine ecosystems. However, Life Cycle Assessment data and methods don't exist to quantify these effects. This doesn't mean we should ignore the problem, but only recognize that Life Cycle Assessment isn't currently an appropriate tool to address it.

Even when we do have available data and acceptable methods, Life Cycle Assessment provides only an approximation of environmental impacts. Both the data and the LCIA methods include uncertainty. Thus, Life Cycle Assessment should be viewed as guidance for understanding the likely areas of impact.

Like the dual approach to sustainability, Life Cycle Thinking and Life Cycle Assessment should be approached in the same vein. We use Life Cycle Assessment where adequate systems of measurement exist, but must continue to use Life Cycle Thinking to assess the consequences of our actions in a long-term, holistic manner. It's often said that “we treasure what we measure.” If we limit our analyses to systems and impacts we can quantify, we will focus on some impacts (e.g., carbon emissions) while potentially ignoring others (e.g., biodiversity loss). Someday, we may have sophisticated Life Cycle Assessment data and methods to assess a wider range of issues.

But until then, we must recognize the limits of Life Cycle Assessment as a tool.