Use of methyl bromide (MeBr) as a quarantine, commodity, or structural fumigant is under scrutiny because its release to the atmosphere contributes to the depletion of stratospheric ozone. A closed-system bioreactor consisting of 0.5 L of a growing culture of a previously described bacterium, strain IMB-1, removed MeBr (>110 μmol L-1) from recirculating air. Strain IMB-1 grew slowly to high cell densities in the bioreactor using MeBr as its sole carbon and energy source. Bacterial oxidation of MeBr produced CO2 and hydrobromic acid (HBr), which required continuous neutralization with NaOH for the system to operate effectively. Strain IMB-1 was capable of sustained oxidation of large amounts of MeBr (170 mmol in 46 d). In an open-system bioreactor (10-L fermenter), strain IMB-1 oxidized a continuous supply of MeBr (220 μmol L-1 in air). Growth was continuous, and 0.5 mol of MeBr was removed from the air supply in 14 d. The specific rate of MeBr oxidation was 7 × 10-16 mol cell-1 h-1. Bioreactors such as these can therefore be used to remove large quantities of contaminant MeBr, which opens the possibility of biodegradation as a practical means for its disposal.
Additional publication details
|Publication Subtype||Journal Article|
|Title||Bioreactors for removing methyl bromide following contained fumigations|
|Series title||Environmental Science & Technology|
|Contributing office(s)||Toxic Substances Hydrology Program|
|Google Analytic Metrics||Metrics page|