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The yield of organic cotton farming was assumed 30 % lower than conventional cotton. For the modelling, this implies that 30 % more impacts are considered for the production of organic cotton than conventional cotton. The yield was found to vary in the literature between 20 % and 40 % and according to the geographical location (Forster et al., 2013). Since the Ecoinvent dataset for cotton production is not linked to a specific geographical location, but is based on a global average, 30 % was considered as average value. The selected value influences the contribution of the production process to the overall impacts related to the organic cotton carrier bag.

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In the case of organic cotton (COTorg), production contributed to 99 % of the impact, 98 % and 96% for COT and COM scenarios, respectively. The contribution analysis for the production phase of these bags is provided in Tables 19 – 21. The high environmental cost of the cotton production can be ascribed to the energy and material required, which is responsible for 80 % of the climate change impacts. In general, the results showed very little difference between EOL1 and EOL3, due to the comparatively small weight of the avoided waste bin bag in comparison to the mass (and resources required for its production) of the cotton bag. The same behaviour was observed for all impact categories, as well as for COT and COM, even if with a lower magnitude in the impacts.
The environmental impacts connected to the production of the organic cotton bag (COTorg) were considerably higher than those of the conventional cotton bag (COT). This is due to the fact that organic cotton production does not involve the use of synthetic chemicals such as fertilizers and pesticides, which lowers the yield of the cultivation. Eventually, more resources and land are required to produce the same amount of cotton than in conventional cotton cultivation processes