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  • amines
  • In foods, nitrosamines are produced from nitrites and secondary amines, which often occur in the form of proteins. (wikipedia.org)
  • The results of this study demonstrate that the nitrosation of hydrophobic secondary amines (e.g., dipropylamine, dibutylamine) by nitrite was significantly enhanced in the presence of micelles of the cationic surfactant cetyltrimethylammonium chloride whereas anionic micelles formed by sodium dodecylsulfate did not significantly enhance the formation of N -nitrosamines. (rsc.org)
  • Cured meat is also added with sodium ascorbate (or erythorbate or vitamin C). As demonstrated by S. Mirvish, ascorbate inhibits nitrosation of amines to nitrosamine, because ascorbate reacts with NO− 2 to form NO. Ascorbate and pH 5 thus favor nitrosylation of heme iron, forming nitrosylheme, a red pigment when included inside myoglobin, and a pink pigment when it has been released by cooking. (wikipedia.org)
  • NDMA
  • The chemical structure of nitrosodimethylamine (NDMA), also commonly called dimethylnitrosamine, is (CH 3 ) 2 N=N=O. Several nitrosamines have been detected in some drinking waters either from industrial discharges or as byproducts of drinking water treatment, especially chloramination. (watertechonline.com)
  • Upstream wastewater discharges provide organic nitrogen precursors like dimethylamine that can react with dichloramine in a process that leads to ppt amounts of nitrosamines, mostly NDMA. (watertechonline.com)
  • The nitrosamines found in drinking water tend to be the low molecular weight types such as NDMA. (watertechonline.com)
  • This review provides an overview of the current state of knowledge on the prevalence of nitrosamines in drinking water, especially nitrosodimethylamine (NDMA), and discusses published research on the detection, mechanisms of formation, and removal of nitrosamines. (scielo.org.za)
  • Nitrosodimethylamine (NDMA) belongs to a group of extremely toxic and mostly carcinogenic substances, the N-nitrosamines. (scielo.org.za)
  • Recently, in South Africa, the presence of NDMA and other nitrosamines, primarily from food and tobacco smoke, have been implicated as a possible cause of higher incidences of oesophageal cancers amongst Black populations in the former Transkei region (Sammon, 2007). (scielo.org.za)
  • 1988). While there appears to be an epidemiological link between cancers and NDMA levels, a theory which is substantiated by several animal studies, it is not yet understood how nitrosamines cause cancer. (scielo.org.za)
  • If NDMA or other nitrosamines become regulated drinking water contaminants in the future, the method could also be used for compliance monitoring. (epa.gov)
  • exposures
  • Tobacco smoking is a source of nitrosamine exposures. (watertechonline.com)
  • Explain to interested patients that this study compared epidemiological trends to identify a possible link between nitrosamine exposure and diseases characterized by insulin resistance, but did not actually measure exposures in patients. (medpagetoday.com)
  • Occupational nitrosamine exposures from a rubber vehicle seal (VS) curing operation were compared with the peripheral blood lymphocyte concentrations of two nitrosamine-related DNA adducts. (cdc.gov)
  • The occupational personal breathing zone (PBZ) nitrosamine exposures ranged from 0.4 to 9.3 ug/m3 in the VS area, from 0.1-2 ug/m3 in an area remote from the VS and were not detected at a nearby rubber plant. (cdc.gov)
  • Although no association was found between PBZ exposure and either the N7mdG adduct concentrations or AGT activity, the significant positive association between working in and near the VS department and the presence of 06mdG adducts, which have mutagenic potential, provides evidence to link nitrosamine exposure one step closer to human cancer by demonstrating an association between external nitrosamine exposures and cancer-related biological effects. (cdc.gov)
  • Occurrence
  • The method was developed for inclusion in EPA's Unregulated Contaminant Monitoring Rule, scheduled for proposal in 2005, in order for the EPA Office of Water to collect nationwide occurrence data on nitrosamines in drinking water and make a regulatory determination. (epa.gov)
  • exposure
  • LITTLE FALLS, N.J., July 6 -- Rising mortality rates for diabetes, Alzheimer's disease, and Parkinson's disease in recent decades parallel increased exposure to nitrosamines in the food supply and environment, researchers found. (medpagetoday.com)
  • To explore a possible connection between nitrosamine exposure and the rates of diabetes, Alzheimer's disease, and Parkinson's disease, Dr. de la Monte and her colleagues tracked mortality trends from 1968 to 2005. (medpagetoday.com)
  • These patterns were compared with trends in the consumption of fast food, use of nitrite-containing fertilizers, sales from a major meat processing company, and consumption of grain -- all indirect measures of exposure to nitrosamines -- from 1955 to 2005. (medpagetoday.com)
  • O6-methylguanine DNA adducts associated with occupational nitrosamine exposure. (cdc.gov)
  • With the exception of medicinal nicotine products, low-nitrosamine ST products have the greatest potential to result in reduced toxicant exposure compared with other combustible reduced exposure products and have promise for reducing individual risk for disease. (nih.gov)
  • There is a need for an occupational exposure limit for N-nitrosamines in Sweden. (sjweh.fi)
  • The lack of exposure-response relationships with the subacute symptoms examined in this study may be due to a healthy-worker selection or to the possibility that the symptoms are caused by an exposure not co-varying with N-nitrosamines. (sjweh.fi)
  • chemistry
  • Advanced oxidation processes involving peroxide and UV are also used, but the data indicates that most of the nitrosamine decomposition is from direct UV photolysis rather than hydroxyl radical chemistry. (watertechonline.com)
  • R. Andrade, F. G. R. Reyes and S. Rath, "A Method for the Determination of Volatile N-nitrosamines in Food by HS-SPME-GC-TEA," Food Chemistry, Vol. 91, No. 1, 2005, pp. 173-179. (scirp.org)
  • In accepting that nitrosamines can be by-products of it's manufacturing chemistry, the rubber industry has already started to address the possibilities for reformulation. (chemtec.org)
  • processes
  • Fermentation and heating processes contribute to nitrosamine formation. (watertechonline.com)
  • These results suggest that cationic micelles-forming surfactants might play a role in the formation of N -nitrosamines in wastewater, consumer products and in industrial processes using high concentration of cationic surfactants. (rsc.org)
  • gastric
  • At present, available epidemiological evidence from case-control studies on nitrite and nitrosamine intake supports a positive association with gastric cancer risk. (wikipedia.org)
  • Regarding oesophageal cancer, available evidence supports a positive association between nitrite and nitrosamine intake and gastric cancer (GC), between meat and processed meat intake and GC and oesophageal cancer, and between preserved fish, vegetable and smoked food intake and GC, but is not conclusive. (wikipedia.org)
  • aromatic
  • A good example is (CH3)3CNO, known formally as 2-methyl-2-nitrosopropane, or t-BuNO, which is prepared by the following sequence: (CH3)3CNH2 → (CH3)3CNO2 (CH3)3CNO2 → (CH3)3CNHOH (CH3)3CNHOH → (CH3)3CNO (CH3)3CNO is blue and exists in solution in equilibrium with its dimer, which is colorless, m.p. 80-81 °C. In the Fischer-Hepp rearrangement aromatic 4-nitrosoanilines are prepared from the corresponding nitrosamines. (wikipedia.org)
  • Mechanisms
  • The biochemical mechanisms of the carcinogenicity and the structure-activity relationship of the nitrosamines have since been studied by many investigators and the results have been summarized in three recent symposia (3-5). (springer.com)
  • found
  • They are called tobacco-specific nitrosamines because they are found only in tobacco products, and possibly in some other nicotine-containing products. (wikipedia.org)
  • Nitrosamines can also be found in e-cigarette vapour, though this is reported to be trace amounts, possibly from the propylene glycol and/or vegetable glycerine used in manufacture. (wikipedia.org)
  • Conclusions High levels of N-nitrosamines were found and must be lowered considerably in order to decrease the risk of cancer. (sjweh.fi)
  • Rubber Industry
  • Objectives The aim of this study was twofold: (i) to evaluate the air levels of N-nitrosamines in the Swedish rubber industry and (ii) to estimate the risk of symptoms and changed levels of immunologic markers in relation to these levels. (sjweh.fi)
  • Detection
  • L. Cardenes, J. H. Ayala, V. González and A. M. Afonso, "Fast Microwave-Assisted Dansylation of N-nitrosamines Analysis by High-Performance Liquid Chromatography with Fluorescent Detection," Journal of Chromatography, Vol. 946, No. 1-2, 2002, pp. 133-140. (scirp.org)
  • Results The sum of N-nitrosamines ranged from less than the limit of detection to 36 µg/m 3 and differed with the vulcanization (ie, curing process) method used. (sjweh.fi)