Mercury used in products in the U.S.

Material Flow Analysis MFA
Source:  Alexis Cain, Sarah Disch, Cliff Twaroski, John Reindl, and C. Randy Case, 2007. Substance Flow Analysis of Mercury Intentionally Used in Products in the United States.

This is a quite precise Material Flow Analysis diagram of mercury intentionally used in fluorescent lamps in 2005. 

The substance flow models for each product estimate mercury releases… by combining data on the amount of mercury in products produced or sold with distribution factors that indicate what happens to mercury though the product life cycle. This technique yields estimates of the distribution of mercury-containing products, which are then combined with release factors to estimate the amount of mercury released to air, water, and land…

...[shown here] a flow model for one of the products, fluorescent lamps, in 2005. Air releases are shown across the top of the figure, water releases at the bottom, and releases to land at the right. The mercury flow begins with lamp production and then proceeds to retailers and then consumers, with small losses to air and to wastewater treatment plants at each step as lamps are broken. Additional losses of mercury are shown as waste lamps are transported from consumers to municipal solid waste treatment and lamp recycling, and further losses occur from burn barrels, 4 incinerators, landfills, recycling, and other disposal options. Mercury inputs to wastewater treatment plants partition to water discharges or to sludge and grit, which are subsequently land applied or disposed of. Perhaps surprisingly, the model shows higher mercury releases from transport of waste lamps in the solid waste recycling system than from disposal processes themselves. In addition, in this model, 2005 environmental releases plus mercury recovery exceed inputs, because these outputs are based on prior year purchases of lamps, when mercury content of lamps was higher.

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