Volatile Organochlorine Compounds Emitted by Temperate Coniferous Forests

Chlorine is one of the most abundant elements in nature, which undergoes a complex biogeochemical cycle. Chlorine bound in some substances is partly responsible for atmospheric ozone depletion and contamination of some ecosystems. As due to international regulations anthropogenic burden of volatile organochlorines (VOCls) in atmosphere decreases, natural sources (plants, soil, abiotic formation) are expected to dominate VOCl production in the near future. Examples of plant VOCl production are methyl chloride, and bromide emission from (sub)tropical ferns, chloroform, 1,1,1-trichloroethane and tetrachloromethane emission from temperate forest fern and moss. Temperate forests are found to emit in addition to the previous compounds tetrachloroethene, and brominated volatile compounds. VOCls can be taken up and further metabolized in plants. The aim of this work is to identify and quantitatively analyze the formed VOCls in temperate forest ecosystems by a cryofocusing/GC-ECD detection method, hence filling a gap of knowledge in the biogeochemical cycle of chlorine.




References:
[1] Kringstad, K. P., et al., "Identification and mutagenic properties of some
chlorinated aliphatic-compounds in the spent liquor from kraft pulp
chlorination," Environ. Sci. Technol. 15(5), 562 (1981).
[2] Hoekstra, E. J., de Leer, E. W. B., and Brinkman, U. A. T., "Natural
formation of chloroform and brominated trihalomethanes in soil,"
Environ. Sci. Technol. 32, 3724 (1998).
[3] Rhew, R. C., Miller, B. R., and Weiss, R. F., "Natural methyl bromide
and methyl chloride emissions from coastal salt marshes," Nature
403(6767), 292 (2000).
[4] G. Asplund, "Origin and occurrence of halogenated organic matter in
soil,"in Naturally-produced organohalogens, edited by A. Grimvall and
E. W. B de Leer (Kluwer Academic Publ., Dordrecht, 1995), pp.35-48.
[5] Matucha, M., et al., "Biogeochemical cycles of chlorine in the coniferous
forest ecosystem: practical implications," Plant Soil Environ 56(8), 357
(2010).
[6] Bastviken, D., et al., "Chloride retention in forest soil by microbial
uptake and by natural chlorination of organic matter," Geochim
Cosmochim Ac 71(13), 3182 (2007).
[7] Keppler, F., et al., "Halocarbons produced by natural oxidation processes
during degradation of organic matter," Nature 403, 298 (2000).
[8] Gribble, G. W., "The diversity of naturally produced organohalogens,"
Chemosphere 52, 289 (2003).
[9] Laturnus, F. and Matucha, M., "Chloride - a precursor in the formation
of volatile organochlorines by forest plants?," J Environ Radioactiv
99(1), 119 (2008).
[10] Saito, T. and Yokouchi, Y., "Diurnal variation in methyl halide emission
rates from tropical ferns," Atmos Environ 40(16), 2806 (2006).
[11] Butler, J. H., "Atmospheric chemistry: Better budgets for methyl
halides?," Nature 403(6767), 260 (2000).
[12] Lovelock, J. E., Maggs, R. J., and Wade, R. J., "Halogenated
hydrocarbons in and over the Atlantic.," Nature 241, 194 (1973).
[13] Frank, H. and Frank, W., "Photochemical activation of chloroethenes
leading to destruction of photosynthetic pigments," Experientia 42, 1267
(1986).
[14] Forczek, S. T., et al., "Trichloroacetic acid of different origin in Norway
spruce needles and chloroplasts," Biol Plantarum 52(1), 177 (2008).
[15] Laturnus, F., "Release of volatile halogenated organic compounds by
unialgal cultures of polar macroalgae," Chemosphere 31(6), 3387
(1995).