Aromatic amines are a group of chemicals whose ubiquitous presence in the environment is a result of the multitude of sources from which they originate. These compounds are widely used as raw materials or at intermediate stages in the manufacturing of industrial chemicals such as pesticides, medicines, dyestuffs, polymers, surfactants, cosmetics and corrosion inhibitors, especially in dyestuff ...

'Steroid hormones are essential for the growth, differentiation and function of many tissues in both animaIs and humans. It has been established by animal experimentation that modification of the hormonal environment by surgical removal of endocrine glands, by pregnancy or by exogenous administration of steroids can increase or decrease the spontaneous occurrence of tumours or the induction of ...

Various inbred strains of mice show pronounced differences in susceptibility to carcinogenic agents. Previous experiments (2) with CBA, C3H , CHI, NH, and JK mice revealed that C3 H and JK mice were respectively most and least susceptible to tumors induced by subcutaneous injection of methylcholanthrene. The F1 progeny of the C3H and JK strains have been used in additional investigation of the ...

In making judgments as to the cancer risk from low level exposure to carcinogens it is generally necessary to base these judgments on high dose or high incidence data from laboratory or epidemiological studies. The biological considerations involved in making such extrapolations are discussed, as well as some of the mathematical procedures. The difficulties presented by moving from species to s...

Pi-class glutathione-S-transferase (GSTP1) located on chromosome 11q13 encodes a phase II metabolic enzyme that detoxifies reactive electrophilic intermediates. GSTP1 plays an important role in protecting cells from cytotoxic and carcinogenic agents and is expressed in normal tissues at variable levels in different cell types. Altered GSTP1 activity and expression have been reported in many tum...

The data from this preliminary experiment make it appear that continuous administration of progesterone protects animals from the synergism between estrogen and radiation. However, it also appears that the progesterone has by itself a protective effect against the individual carcinogenic agents since fewer tumors occurred on the opposite side as well as on the radiated side. In this preliminary...

ln 1969, the International Agency for Research on Cancer (lARe) initiated a programme to evaluate the carcinogenic risk of chemicals to humans and to produce monographs on individual chemicals. The Monographs programme has since been expanded to include consideration of exposures to complex mixtures of chemicals (which occur, for example, in sorne occupations and as a result of human habits) an...

We examined the efficacy of metallothionein induction in the prevention of the carcinogenic action of ci'.v-platiimin and melphalan administered repeatedly to mice over a relatively long period. The increased pulmonary metallothionein induced by bismuth or zinc compounds during the period of chemotherapy with (-/¿-platinumor melphalan protected the mice from carcinogenesis of these drugs in th...