TABLE OF CONTENTS A life cycle assessment (LCA) consists of four independent elements (ISO [1-4]; CML [5]):
the definition of goal and scope,
the life cycle inventory analysis,
the life cycle impact assessment and
the life cycle interpretation.
The definition of the goal and scope includes a decision about the functional unit which forms the basis of comparison, the product system to be studied, system boundaries, allocation procedures, assumptions made and limitations. The functional unit can either be a certain service or a product, with the latter being the usual choice for the type of studies reviewed here, e.g., comparison of 1 m 3 loose-fill packaging material made of starch polymer versus PS. Critical LCA issues regarding biodegradable polymers are, among others, the share of renewable versus fossil fuel raw materials, the way of growing the agricultural raw materials (intensive versus extensive cultivation), the type of conventional polymer that is chosen as a reference and the mix of waste management processes assumed for both the biodegradable and the non-degradable polymer (landfilling, incineration, recycling, composting and digestion). It is generally assumed that the carbon dioxide originating from the biomass is equivalent to the amount which was previously withdrawn from the atmosphere during growth and that it therefore does not contribute to global warming (fossil fuels required for transport, processing the crops and producing auxiliaries, e.g., fertilisers, are accounted for separately).
The life cycle inventory analysis involves data collection and calculation procedures...
