Iodinated X-Ray contrast media

Recently, Duirk et al. [34] showed evidence that iodinated X-ray contrast media (ICM), such as iopamidol, constitute an iodine source to form iodo-THM DBFs, e.g., dichloroiodomethane, and iodo-acid DBFs, e.g., iodoacetic acid, in chlorinated and chloraminated drinking waters. However, the complete reaction pathway is not fully understood yet, and it is under further investigation. Chloraminated and chlorinated source waters with iopamidol were genotoxic and cytotoxic in mammalian cells. This is in agreement with the previously reported high genotoxicity and cytotoxicity of the iodo-acids and iodo-THMs [20, 21]. 

Kalsch, W. (1999) Biodegradation of the iodinated X-ray contrast media diatrizoate and iopromide. Science cfthe Total Environment 225,143-153. 

Methylene iodide [75-11-6], CH2I2, also known as diio dome thane, mol wt 267.87, 94.76% I, mp 6.0°C, and bp 181°C, is a very heavy colorless Hquid. It has a density of 3.325 g/mL at 20°C and a refractive index of 1.7538 at 4°C. It darkens in contact with air, moisture, and light. Its solubiHty in water is 1.42 g/100 g H2O at 20°C it is soluble in alcohol, chloroform, ben2ene, and ether. Methylene iodide is prepared by reaction of sodium arsenite and iodoform with sodium hydroxide reaction of iodine, sodium ethoxide, and hydroiodic acid on iodoform the oxidation of iodoacetic acid with potassium persulfate and by reaction of potassium iodide and methylene chloride (124,125). Diiodoform is used for determining the density and refractive index of minerals. It is also used as a starting material in the manufacture of x-ray contrast media and other synthetic pharmaceuticals (qv). 

X-ray contrast media are usually highly concentrated aqueous solutions. A typical product contains 300-370 mg iodine/ml, which corresponds to about 600-800 mg of the iodinated organic molecule per ml. The high concentration of the contrast substance leaves limited room for water (about 0.7 ml per ml of contrast agent) and restricts the design of the molecules because... 

In all countries with developed medical care, X-ray contrast media can be expected to be present at appreciable quantities in sewage water. Clara et al [13] detected iopromide at a mean concentration of 3.84 pg in the influent of a WWTP receiving hospital wastewater, while in WWTPs without a hospital within their drainage area this contrast media was not present. lodinated X-ray contrast media are proved to contribute significantly to total absorbable organic iodine in clinical wastewaters up to 130 pg of iodine in the influent of municipal WWTP in Berlin and 10 mg in hospital sewage was detected [23]. 

BETA-BLOCKERS X-RAY CONTRAST SOLUTIONS Beta-blockers are associated with T risk of anaphylactoid reactions to iodinated X-ray contrast materials Uncertain, but postulated that beta-receptors have a role in suppressing the release of mediators of anaphylaxis Consider using low-osmolality contrast media and pretreating with antihistamines and corticosteroids. Stopping beta-blockers a few days before the X-ray is associated with a risk of withdrawal t BP and tachycardia a risk-benefit assessment must therefore be made... 

The radio-opacity of X-ray contrast media depends on the fact that they contain substances that have high atomic numbers, which absorb X-rays. Bismuth, now largely obsolete, has an atomic number of 83, barium 56. Since the soluble salts of barium are poisonous, the insoluble salt, barium sulfate, is used as a suspension. Soluble contrast media are based on iodine, which has an atomic number of 53. This means that in principle they can have the various adverse effects of other iodine-containing compounds. 

Kontrastmittel ausgelbst und provozierbar. [Paraneoplastic multicentric reticulohistiocytosis induced and inductable by iodine containing x-ray contrast media.] Z Hautkr 1985 60(9) 729-36. 

Meglumine is an organic base used as a pH-adjusting agent and solubilizing agent primarily in the preparation of soluble salts of iodinated organic acids used as X-ray contrast media. 

Actomar AI3-08544 Caswell No, 501 Diiodine EINECS 231-442-4 EPA Pesticide Chemical Code 046905 Eranol Ethanolio solution of iodine HSDB 34 lODE Iodine iodine (resublimed) Iodine-127 Iodine colloidal Iodine crystals Iodine solution Iodine sublimed Iodine Tincture DSP lodio losan superdip Jod Jood Molecular Iodine NSC 42355 Tincture iodine Vistarin. Nonmetallic halogen element dyes, alkylation and condensation catalyst, iodides, iodates, antiseptics, germicides, x-ray contrast media, food and feed additive, stabilizers, photographic film, water treatment,... 

Iodo derivatives are particularly interesting members of the halogenated aromatic hydroxy and amino carboxylic acids, for they are intermediates for the preparation of X-ray contrast media. They have been successfully prepared by iodination with IC1, which will therefore be treated in this Section (but see also page 165). 

OTHER COMMENTS used in the manufacture of dyes (aniline dyes, phthalein dyes), iodine compounds (iodides, iodates), antiseptics, and germicides used to reduce friction of hard surfaces, including glass and stainless steel also used as an alkylation and condensation catalyst in the preparation of aromatic amines, in sulfonations and sulfations useful as x-ray contrast media, as stabilizers, food and feed additives, and in water treatment important reagent in analytical chemistry has also been used in pharmaceuticals and medicinal soaps artificial isotopes of iodine are used in biochemical, biological, and chemical structure research. 

The qualitative and quantitative analysis of iodine containing X-ray contrast media and their metabolites in environmental waters of the city of Berhn (Germany), in raw and treated sewage, in surface waters, bank filtrate and raw drinking water, was performed by ESl-LC-MS and MS/MS in positive mode [406, 407]. Concentrations observed were 1.6-20.7 pg L [403]. 

Nowadays, iodine is widely used for the manufacturing of X-ray contrast media, antimicrobial products, as tinctures of polyvinylpyrrolidone-iodine (Povidone-iodine), catalysts in chemical processes (e.g. for the production of acetic acid by carbonylation of methanol in the presence of a rhodium iodide-catalyst (Monsanto process) or an iridium iodide-catalyst (Cativa process)), and also on a smaller scale for the production of pharmaceuticals like thyroid hormones. [ 83 ]... 

The iodine atom has a pronounced abihty to scatter X-ray radiation, and soluble iodine compounds are utilized as X-ray contrast media. 

The entire procedure can be automated on continuous flow instruments, with the use of a digestor. The main disadvantage of protein-bound iodine determinations is interference from iodine-containing compounds such as drugs and X-ray contrast media. 

Why are barium- and iodine-based materials selected for contrast media The production of X-ray images depends on the differences between the X-ray absorbing power of various tissues. This difference in absorbing power is called contrast and is directly dependent on tissue density. To artificially enhance the ability of a soft tissue to absorb X-rays, the density of that tissue must be increased. The absorption by targeted soft tissue of aqueous solutions of barium sulfate and iodized organic compounds provides this added density through the heavy metal barium and the heavy nonmetal iodine. 

The use of gadolinium-based contrast media for radiographic examinations is not recommended to avoid nephrotoxicity in patients with renal impairment, since they are more nephrotoxic than iodinated contrast media in equivalent X-ray attenuating doses... 

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