LCA Food 2012 in Saint Malo, France! - Manifestations et colloques ...

PLENARY SESSION 2: METHODOLOGICAL CHALLENGES FOR ANIMAL PRODUCTION SYSTEMS8 th Int. Conference on LCA in the
Agri-Food Sector, 1-4 Oct 2012
labour income includes wages (worker salaries, payments and fringe benefits) and proprietary income (all
income received by self-employed individuals). Value added to the US economy is a measure of labour income
plus indirect taxes (excise, sales and property taxes, as well as, fees, fines, licenses and permits) and
other property-type income (dividends, interest payments, rents and profits). Within these three areas, the
economic IO analysis measures the direct and indirect economic impacts of the US dairy sector. Direct impacts
stem from dairy production and processing. Indirect economic effects arise from the dairy sector’s purchases
of goods and services from other sectors.
The economic IO analysis was conducted using the IMPLAN IO software for the year 2008 (MIG, Minnesota,
US). The US dairy industry was comprised of five IMPLAN sectors: Dairy cattle and milk production,
Fluid milk and butter manufacturing, Cheese manufacturing, Dry-condensed and evaporated dairy products
and Ice cream and frozen dessert manufacturing. Dairy’s contribution to both the US economy and to overall
agricultural economic activity was computed using methods described by Popp et al., (2010).
The social analysis uses SSA to calculate the percentage of worker hours for the supply chain of US dairy
products that are attributable to country-specific sectors. The SSA relies on an extension of the Global Trade
Analysis Project (GTAP) global IO model. This model maps 2008 worker hours for the supply chain of dairy
products according to the sectors and countries involved in production (Benoît-Norris et al., 2012; Benoît et
al., 2011). As with the economic IO model, the supply chain analysis is conducted at the sector level. The
sector classification scheme for the SSA differs from the scheme used in the economic IO analysis (see Discussion
section). The SSA includes the GTAP sectors “Raw Milk” and “Dairy Products”. Raw Milk refers to
dairy farming and Dairy Products is comprised of manufactured dairy products, specifically the following
United Nations Central Product Classification categories: Processed liquid milk, Cream, Milk and cream in
solid forms, Milk and cream concentrated or containing added sugar or other sweetening, Yoghurt and other
fermented or acidified milk and cream, Dairy products n.e.c., Butter and other fats and oils derived from
milk, Cheese and curd, Lactose and lactose syrup, Ice cream and other edible ice, Casein. Results of the SSA
identify potential social hotspots throughout the US dairy supply chain. Presenting the share of worker hours
according to country-specific sectors is particularly relevant because social impacts often manifest through
employment (socialhotspot.org). In addition, a literature review examines social issues of on-farm dairy production
in the US but does not include other stages of the dairy life cycle. A review of social impacts for
other life cycle stages will be included in future research.
3. Results
Environmental impacts for the life cycle of fluid milk consumed in the US are presented in Figure 1 by IM-
PACT 2002+ category and life cycle stage. Farming stages of the life cycle, including feed production and
dairy farming, contribute significantly (50+%) to several impact categories, including land occupation, terrestrial
acidification/nitrification, respiratory organics and respiratory inorganics. The feed production stage
is responsible for 99% of land use and ecosystem impacts through land occupation for crop production.
Farming stages are responsible for 95% of terrestrial acidification/nitrification, particularly through on-farm
release of ammonia, which can be oxidized to nitric acid in the environment.
Approximately 50% of human health impacts, comprised of respiratory organics, respiratory inorganics, and
carcinogens, occur by the farm gate. The principal sources of respiratory organics are on-farm releases of
volatile organic compounds, primarily ethanol released from the fermentation of silage. Field application of
fertilisers (especially urea), manure management, off-farm energy generation and dust from operations contribute
to respiratory inorganics. Farming stage fuel use contributes to carcinogens primarily through release
of aromatic hydrocarbons associated with deep supply chain natural gas extraction and processing.
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