Culture growth was monitored by cell counts and chlorophyll analysis. Species tested include Isochrysis galbana, Phaeocystis globosa, Chaetoceros sp., Emiliania huxleyi and Thalassiosira gravida. Methyl chloride, methyl bromide and methyl iodide production has been detected for most species and some negative production, i.e. apparent uptake of halocarbons by the culture has also been observed. DMS production has also been detected. The mechanisms behind halocarbon production by phytoplankton are poorly understood.
Further experiments involving grazing and nutrient manipulation are underway.
It is anticipated these will allow the mechanism of halocarbon production by marine phytoplankton to be investigated and results from some of these experiments will be discussed. The pattern of halocarbon production during the growth cycle will be compared between species and the significance of this halocarbon production on a global scale will be discussed.