Probably most people who are environmentalists are aware of the contemptuous refusal of the Christie Whitman era EPA to ban methyl bromide as a fumigant for strawberry crops in California.
Anyone who confused Whitman with an "environmentalist"
before she betrayed her home state by suspending coal emission rules and before she got into the climate change denial business, should have been aware of what she was from the methyl bromide action alone.
(Christie Whitman is a supporter, as I am, of nuclear power, but support for the world's largest, by far, form of climate change gas free energy
alone does not make one an environmentalist.)
Methyl bromide is one of the most potent ozone depleting chemicals there is.
As it happens though, methyl bromide, unlike chlorofluorocarbons, is a
naturally occurring chemical.
Tonight, while I was looking for something else, I came across one of those articles you really don't expect to see. Apparently the fourth largest source of methyl bromide is, after the ocean, fumigation, and biomass burning, the crop rapeseed, which is grown for it's oil (canola oil). Note that this is not because methyl bromide is being used as a pesticide, but because the plant forms methyl bromide.
The reference is Shallcross
et al Atmospheric Environment 42 (2008) 337–345.
Methyl bromide (CH3Br) is the most abundant bromine containing organic compound in the free troposphere and is sufficiently long lived to be an important carrier of bromine to the lower stratosphere...
...Under the Montreal Protocol and its amendments, sales and consumption of CH3Br are now proscribed in non-article 5 (developed) countries...
...However, sources of CH3Br appear to be widespread, of both anthropogenic and biogenic origin...
Terrestrial higher plants, such as the Brassicas, appear to be another sizable source of CH3Br. These include agriculturally important species such as rapeseed, cabbages and mustard...
...Work by Saini et al. (1995) found that certain enzymes and tissues in higher plants can convert bromide to CH3Br. Attieh et al. (1995) isolated the enzyme S-adensoyl-L-methionine: halide/bisulphide methyltransferase from Brassica Oleracea ‘April Red’ which is capable of synthesising methyl halides from halides...
...Cabbages are a versatile and widespread kitchen crop, as are the mustards. There are also programs being developed to use certain oilseed crops such as mustards in the production of bio-diesels and biopesticides...
...In Europe, in particular, rapeseed is the primary crop grown specifically for biofuel use and in 2003 the European Union set a target of 5.75% of all transport fossil fuels to be replaced with biofuels by 2010 for each European Union member (OJEU, 2003). These commission goals, combined with rising fossil fuel prices as well as growing fuel demands from Asia, are likely to lead to continued interest in biofuels and, accordingly, rapeseed growth (Bendz, 2005).
We note that since 1961 the estimated volume of emissions of CH3Br from rapeseed has increased by
a factor of 10, and since 1980 by a factor of 3–4.
And here you were thinking that the main drawback to biofuels was the destruction of the Gulf of Mexico and the destruction of the Sumatran rain forest.
Who knew?
The abstract is here:
Rapeseed As A Source of Methyl Bromide