Open AccessRemoval of methyl bromide in coastal seawater: Chemical and biological rates
Author(s) -
King Daniel B.,
Saltzman Eric S.
Publication year - 1997
Publication title -
journal of geophysical research: oceans
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/97jc01214
Subject(s) - seawater , bromide , isotope dilution , particulates , environmental chemistry , chemistry , isotope , gas chromatography , filtration (mathematics) , tracer , mass spectrometry , chromatography , oceanography , inorganic chemistry , organic chemistry , geology , physics , statistics , mathematics , quantum mechanics , nuclear physics
A stable isotope tracer technique was used to investigate the loss rate of methyl bromide in surface ocean waters. Unfiltered and 0.2 μm‐filtered or autoclaved aliquants of Biscayne Bay seawater samples were spiked with 13 CH 3 Br at roughly 10–100 times ambient concentrations (50–800 p M ) and incubated for 10–30 hours. The concentration of 13 CH 3 Br was monitored using gas chromatography with isotope dilution mass spectrometry, with CD 3 Br as the isotope spike. Removal rates in unfiltered aliquants were significantly faster than in the 0.2 μm‐filtered or autoclaved aliquants, indicating that some of the loss of methyl bromide was associated with particulate matter. Filtration experiments indicate that the particulate material responsible for methyl bromide loss is between 0.2 and 1.2 μm in diameter, suggesting that bacteria are likely to be responsible. The particulate‐related removal of methyl bromide was inhibited by autoclaving, supporting a biological mechanism.