Atmospheric iodine

Moore, R. M., and R. Tokarczyk, Chloro-Iodomethane in N. Atlantic Waters A Potentially Significant Source of Atmospheric Iodine, Geophys. Res. Lett., 19, 1779-1782 (1992). 

In summary, the IO + DMS reaction appears to be potentially important in iodine-ozone chemistry and in controlling the DMS behavior in the marine atmosphere. However, the role of this reaction remains to be confirmed by direct field measurements of key species such as IO and CH3I and also by further laboratory measurements on key reactions of the atmospheric iodine chemistry. 

Computational Studies of the Thermochemistry of the Atmospheric Iodine Reservoirs HOI and IONO2... 

H.-E. Gabler, K. G. Heumann, Determination of atmospheric iodine species using a system of specificly prepared filters and IDMS, Fresenius J. Anal. Chem., 345 (1993), 53-59. 

Duce RA, Watson JT, Winchester JWand Burns F (1963) Atmospheric iodine, bromine and chlorine. J Geophys Res 68 3943. 

In general, soluble forms of iodine seem to be easily available to plants therefore, terrestrial plants contain much less iodine than do marine plants, which are known to concentrate iodine from 50 to 8800 mg kg DM (Shaklette and Cuthbert 1967). Organically bound iodine is scarcely available to plants soil iodine becomes available after the decomposition of organic matter by bacteria (Selezniev and Tiuriuka-nov 1971). Atmospheric iodine also contributes to the iodine content of plants (Kabata-Pendias and Pendias 1992), as plants can... 

As part of the biogeochemical cycle, the injection of iodine-containing gases into the atmosphere, and their subsequent chemical transformation therein, play a crucial role in environmental and health aspects associated with iodine - most importandy, in determining the quantity of the element available to the mammalian diet. This chapter focuses on these processes and the variety of gas- and aerosol-phase species that constitute the terrestrial iodine cycle, through discussion of the origin and measurement of atmospheric iodine in its various forms ( Sources and Measurements of Atmospheric Iodine ), the principal photo-chemical pathways in the gas phase ( Photolysis and Gas-Phase Iodine Chemistry ), and the role of aerosol uptake and chemistry and new particle production ( Aerosol Chemistry and Particle Formation ). Potential health and environmental issues related to atmospheric iodine are also reviewed ( Health and Environment Impacts ), along with discussion of the consequences of the release of radioactive iodine (1-131) into the air from nuclear reactor accidents and weapons tests that have occurred over the past half-century or so ( Radioactive Iodine Atmospheric Sources and Consequences ). 

Figure 8.1 Schematic of the production, transfer, and ioss processes for atmospheric iodine.

In the lower atmosphere, iodine destroys reactions ozone via the... 

The main sources of atmospheric iodine are biogenic, i.e., phytoplankton in the open ocean and certain seaweed species at coastal sites, with some likely contribution from chemical transformation of in seawater. 

The major impact of atmospheric iodine chemistry is the resultant depletion of O3, while other consequences, such as enhanced cloud formation, remain to be established. 

Iodine is an essential element in humans and other mammals, which is used for the synthesis of the thyroid hormones triiodothyronine (T3) and thyroxine (T4). These hormones play a prominent role in the metabolism of most cells of the organism and in the process of early growth and development of most organs, especially brain (Anderson et al., 2000). Besides T3 and T4, reverse T3 (rT3), monoiodotyrosine (MIT), and diiodotyrosine (DIT) are also synthesized and distributed in the body of humans and animals, but only T3 and T4 have a biological function. Iodine in the human body mainly comes through dietary and water intake, and inhalation of atmospheric iodine. Due to low concentrations of iodine in the air (10—20ng/m ), food and water intake form the major source of iodine for adults, while for infants it is milk. The concentration of iodine in foodstuffs is directly related to that in the environment where the foods come from. Iodine deficiency disorders are mainly found in places where the concentration of iodine in the soil and drinking water is very low. In the water, foodsmffs, and... 

Iodine is an essential element to humans and presents in the human body in minute amounts (15-20mg in adults), of which more than 80% exists in the thyroid gland. Iodine in the human body mainly comes from food intake and inhalation of atmospheric iodine. In the thyroid, iodine is added to the essential amino acid thyroxine residue on thyroglobulin. 

Field concentration methods can be used to increase the quantity of in certain materials that are collected. Thus, particle filters and activated charcoal filters have been used to collect atmospheric iodine (Brauer et al., 1974a). Ion-exchange methods, usually using anion exchange resins, have been used to sample water-borne iodine and ionic iodine in milk (Daly et al., 1974 Brauer and Rieck, 1973 Brauer et al., 1974b Keisch et al., 1965). Natural iodine collectors, such as thyroid tissue and seaweed, have been used for collection of environmental I samples (Brauer et al., 1974b Keisch et al., 1964 NSEC, 1963 Boulos et al., 1973 Kelleher and Michael, 1973 Smith, 1977 Oliver et al., 1982 Schuttelkopf and Pimpl, 1982). 

Brauer, F.P., Rieck, H.G., Jr. and Hooper, R.L. (1974a). Particulate and gaseous atmospheric iodine concentrations, page 351 in Physical Behavior of Radioactive Contaminants in the Atmosphere, IAEA Publication No. STI/ PUB/354 (International Atomic Energy Agency, Vienna). 

There may be conversion of atmospheric iodine (i.e., iodine suspended in the atmosphere for long time periods) to chemical... 

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