Sources and Sinks of Brominated Organics

TABLE 12.6 Estimated Annual Global Emissions of Halon-1211 (CF2ClBr) and Halon-1301 (CF3Br) from 1963 to 1990 (in 106 kg/year) 

Methyl bromide is used as a fumigant for soils (the agricultural use shown in Table 12.7) and shipments of fruits and vegetables as well as for buildings for termite control (shown as structural purposes in Table 12.7). Large amounts are released during biomass burning (e.g., see Mano and Andreae, 1994 Cicerone, 1994) 

Source Range (lO6 kg/year) Anthropogenic (106 kg /year) Natural (lO6 kg / year) 

Whether production or destruction predominates depends on a number of factors, including temperature and the rate of biological production of CH3Br. As a result, the ocean can serve as either a net source or a net sink, depending on the conditions (e.g., see Anbar et al., 1996 and Pilinis et al., 1996). 

The amount of CH3Br that is applied to soils as a fumigant and that escapes to the atmosphere is also uncertain. For example, Cicerone and co-workers (Yagi et al., 1993, 1995) measured a range from 34 to 87% of the methyl bromide applied to a field that escaped to the atmosphere. Since approximately 80% of synthetic CH3Br use is due to soil fumigation (Shorter et al., 

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