Blood nitrosamines

There have been some preliminary reports of nitrosamines being found in normal humans, in blood (, 35), and in urine (36). The precise origin of these substances, if their presence is confirmed, is not fully understood at this time. 

An attempt to estimate human daily impact of N nitroso compounds is shown in Table I. The apparent intake from food of preformed nitrosamines is comparatively low, at least in these surveys of a Western diet in England (3). The Intake directly to the respiratory tract from smoking could be somewhat larger. However, if the blood levels reported are confirmed as correct, then inputs of up to 700 meg per day of at least N nitrosodimethylamine (NDMA) may be calculated, based on pharmacokinetic considerations of data obtained in animals and extrapolated to man. It should be emphasized that no information is available at present on nitrosamide intake or in vivo formation, largely because of analytical limitations. 

Reliable methods are available for determination of nitrosamines, especially volatile nitrosamines, in a variety of foods, environmental samples, commercial products, blood and animal tissues. Reviews of these methods are available (1, 2) and descriptions of some state-of-the-art procedures are included in papers on nitrosamine occurrence in this volume. This paper is not intended to be a comprehensive review of historical developments or of the many variations of procedures... 

Pancreatic effect. Cigarette smoke, administered to anesthetized rats alone or in combination with iv ethanol infusion, reduced pancreatic blood flow temporarily and increased leukocyte-endothelium interaction (roller p < 0.001, sticker p < 0.01 vs baseline). Cigarette smoke potentiated the impairment of pancreatic capillary perfusion caused by ethanol, and both the number of rolling leukocytes and myeloperoxidase activity levels were increased compared with ethanol or nicotine administration alone h Tobacco-specific nitrosamines, administered to rats, induced pancreatic acinar cell and ductal cell neoplasms. One of the tumors had a mixed ductal-squamous-islet cell components . 

Chemicals which can damage (a) the liver include carbon tetrachloride, paracetamol, bromobenzene, isoniazid, vinyl chloride, ethionine, galactosamine, halothane, dimethyl-nitrosamine (b) the kidney include hexachlorobutadiene, cadmium and mercuric salts, chloroform, ethylene glycol, aminoglycosides, phenacetin (c) the lung include paraquat, ipomeanol, asbestos, monocrotaline, sulfur dioxide, ozone, naphthalene (d) the nervous system include MPTP, hexane, organophosphoms compounds, 6-hydroxydopamine, isoniazid (e) the testes include cadmium, cyclophosphamide, phthalates, ethanemethane sulfonate, 1,3-dinitrobenzene (f) the heart include allylamine, adriamycin, cobalt, hydralazine, carbon disulfide (g) the blood include nitrobenzene, aniline, phenyl-hydrazine, dapsone. 

Armstrong MJ, Galloway SM. 1993. Micronuclei induced in peripheral blood of E p-PIM-1 transgenic mice by chronic oral treatment with 2-acetylaminofluorene or benzene but not with diethyl-nitrosamine or 1,2-dichloroethane. MutatRes 302(l) 61-70. 

E lipid-soluble antioxidant, prevents lipid oxidation of membranes, needed for healthy blood cells and tissues, blocks nitrosamine formation, protects PUFAs from autoxidation, important for normal immune fimction neuromuscular disorders, red blood ceU mpture (both uncommon) reduces risk of chronic disease (cardio-vascular, precancerous lesions, cancer), immunoenhancement, protec-tion from exercise-induced muscle injury, improves metaboHc control, re-duces risk of compHcations in diabetes... 

See also Blood Food Additives Food and Drug Administration, US Food Safety and Toxicology Gastrointestinal System Nitrite Inhalants Nitrosamines Respiratory T ract. 

In vitro and animal studies show that the organosulfur components of garlic suppress tumor incidence in breast, blood, bladder, colon, skin, uterine, esophagus, and lung cancers. Potential mechanisms include decreasing nitrosamine formation, decreased bioactivation of carcinogens, improved DNA... 

Gough TA, Webb KS, Swann PF. 1983. An examination of human blood for the presence of volatile nitrosamines. Fd Chem Toxicol 21 151-156. 

Toxicology LD50 (oral, rat) 3750 mg/kg LDLo (IV, cat) 100 mg/kg poison by IV route mod. toxic by ing. irritant ing. of Ig. quantities can cause gastroenteritis chronic exposure can cause anemia, nephritis can reduce blood oxygen levels experimental teratogen, reproductive effects mutagenic data can produce nitrosamines linked to cancer TSCA listed... 

Compared to oxidation, EC reduction has not been not widely used with HPLC. Reducible groups include hydroxylamines, nitrosamines, -oxides, peroxides, quinones, aromatic nitro compounds and disulfides. The antibiotic chloramphenicol can be assayed in blood by EC reduction using a mercury film electrode. ... 

The nitroso group is generally more easily reducible than the nitro group. Af-Nitrosamines, e.g., (V-nitroso-W-methylaniline in blood, serum, or albumin, are determined in the pg/kg range... 

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