Meat Eaters Guide: Methodology - Environmental Working Group

Meat Eaters Guide: Methodology
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the data system would need to be higher to reduce this calorie total.”
29. See Hall, Kevin D., GUo, Juen, Dore, Michael and Chow, Carson C, “The Progressive Increase of Food
Waste in America and its Environmental Impact” published on line Nov. 25,2009, accessed November 2010
at http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0007940; and Bloom, Jonathan,
American Wasteland, October 2010.
30. Accessed Aug. 5, 2010: http://www.ers.usda.gov/Data/FoodConsumption/FoodGuideSpreadsheets.htm;
31. Data sources for waste are cited in Section C.3. l on data sources
32. Documented further at the Inventory of Carbon and Energy (http://people.bath.ac.uk/cj219/ice00a.pdf)
33. We validate the LCA GHG emissions of edible products produced before processing instead of the emissions
associated with 1kg of that product consumed, since very few peer-reviewed studies have assessed
LCA greenhouse gas emissions of consumed product. Also, it should be noted that the post-farmgate
emissions for most meat products is relatively small compared with their production emissions.
34. It should be noted that some improvements in efficiency that are achieved by larger animal confinement operations
or the use of antibiotics and growth hormones may have deleterious health and/or environmental
impacts. (e.g. such as increased contamination of water and increased antibiotic-resistant strains of bacteria
in humans).
35. The FAO dairy study (2009) found that a 10 percent change in feed digestibility could reduce emissions by
14.8 percent. Adding other factors such as higher milk yield per cow or more digestible feed could reduce
overall emissions associated with one unit of milk by as much as 20 percent in an extensive system and 15
percent in an intensive system.
36. The FAO dairy study found that replacing solid storage with liquid manure systems could increase GHG
emissions by nearly 6 percent, but in other cases changing manure systems did not result in significant
emission changes.
37. According to Phetteplace (2001), intensive grazing reduced the CO 2 e per unit of production by about 10
percent. The FAO dairy study (FAO 2009) also found that intensive grazing systems generate lower emissions
per unit of milk yield per cow.
38. There is evidence that best management practices in grazing can generate a significant reduction in
greenhouse gas emissions through soil and woody matter carbon sequestration. According to Follet, et al.
2001, BMPs in pastureland or rangeland can present significant (potential to offset GHG emissions with
increased soil carbon sequestration. Ryan, et al 2008, found that grazed pasture generated an increase
in soil organic matter of 1.14 percent a year. Johnson, et. al report on a study by Conant et al (2001) that
found an increase of .4 mg/ha in intensive grazing pasture in the southeastern US. Pelletier et al (2010)
found that emissions from grass-fed beef could be reduced by as much as 40 percent in transitional im-
Environmental Working Group Meat Eaters Guide: Methodology 2011