The functional unit of this present study is the, “number of
shopping bags used for grocery shopping per year by an average
Chinese/Indian/HK resident”. For the territories considered for this
study, we assume that plastic and paper bags are comparable and
they are equivalent to each other in their functional front. When it
comes to non-woven and woven bags, we assume that 1 nonwoven
and 2 woven cotton bags will replace 100 single use plastic
and paper bags. Further, our above said assumptions can be validated
from the relevant literature also (Nolan ITU et al., 2002;
ExcelPlas Australia et al., 2004; James and Grant, 2005; Reusable
shopping bags; Envirosax; Alburyenvirobags). Hence 1095 plastic
and paper bags,10.95 non-woven and 21.9 woven bags are required
to fulfill the functional unit assumed for this study for an average
Chinese and HK residents. For Indians, 150 plastic and paper bags,
1.5 non-woven and 3 woven bags are needed to fulfill this study’s
functional unit.
The end-of-life values were derived from a survey conducted in
China, Hong Kong and India as reported in the references in detail
(Muthu et al., 2010a). Results from the survey were used in Life
cycle impact calculations in the usage and disposal states were
compared with the life cycle stage without usage and disposal
criteria.