is the parent strain. A screening test is based upon this greater sensitivity, expressed as inhibition of growth, to potential mutagens and known carcinogens. I We have applied this system to several newly synthesized nitrosamines as a means of selecting agents for long-term animal testing. Our results with compounds that were originally studied have generally agreed with those reported. We hav...

The unexpected finding of presence nitrosamine impurities, by USFDA and EMA in year 2018, drugs such as Angiotensin-II Receptor Blockers (ARBs), Ranitidine, Nizatidine Metformin, has triggered the need for a risk assessment strategy evaluation control these probable human carcinogen - pharmaceutical product that are at risk. This leads to voluntarily recall products worldwide. nitrosamines some...

The metabolism of three cyclic nitrosamines has been studied in Sprague-Dawley rats. The compounds were nitrosopyrrolidine, nitrosohexamethyleneimine, and nitrosohepatamethyleneimine and were labeled at the alpha carbon with 14C. At low doses (2 to 4 mg/animal) the compounds were metabolized to 14CO2 to the extent of 77, 43, and 27%, respectively, after 24 hr. At doses closer to the 50% lethal ...

The environmental analysis of amines is important to preserve human health because these compounds often have toxic effects. Gas chromatography (GC) of free amines is generally unsatisfactory owing to the adsorption and decomposition of the solutes on the column. Derivatization of amines is employed to reduce the polarity and to improve the GC properties. Derivatization reactions for the determ...

Cholangiocarcinoma (CCA) is a major public health problem in the northeastern part of Thailand where the prevalence of this cancer is highest in the world. It is a slow growing tumor but highly metastatic with a poor prognosis. The traditional habit of eating raw fish, repeated exposure to liver fluke and consumption of nitrosamine-contaminated food are major risk factors. Understanding of carc...

The biodegradation of secondary amines is particularly important due to their propensity for conversion either chemically or microbiologically to N-nitrosamines which are potent carcinogens. In this research, a weak Gram-positive organism was isolated from river and identified as Mycobacterium. This Mycobacterium grows slowly and effectively utilizes piperazine as the sole source of organic, c...

There is sufficient evidence for an excess occurrence of stomach and lung cancer among rubber workers. However, evidence for causal associations with specific exposures is still limited. A cohort of 8,933 male German rubber workers was followed for mortality from January 1, 1981 through December 31, 1991. Work histories were reconstructed using routinely documented cost center codes. For each c...