In vivo and in vitro ethylene oxide exposure of human lymphocytes assessed by chemical stimulation of unscheduled DNA synthesis

doi:10.1016/0027-5107(81)90011-7

Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis

Volume 83, Issue 2, September 1981, Pages 271-289

https://doi.org/10.1016/0027-5107(81)90011-7 Get rights and content

Abstract

Factory workers exposed to ethylene oxide (EO), 0.5–1.0 ppm in factory air, together with matched controls from the same factory, were examined for evidence of toxic exposure by measurement of unscheduled DNA synthesis (UDS) induced by N-acetoxy-2-acetylaminofluorene (NA-AAF) and of chromosome aberrations in peripheral lymphocytes.

The total chromatid gaps plus breaks were significantly elevated and NA-AAF-induced UDS was significantly reduced in the EO-exposed group as compared with the unexposed control group. The NA-AAF-induced UDS values negatively correlated to the duration (yr) of EO exposure (r = −0.45, p < 0.02) and the number of chromosome breaks (r = −0.61, p < 0.05), indicating an inhibition in vivo of DNA-repair capacity by EO. These data were verified in vitro by biochemical and autoradiographic studies of EO-induced UDS in human blood cells. Above 2 mM EO, UDS was inhibited in lymphocytes whether they were cultured for 24 or 122 h after alkylation with EO. Even at the subtoxic EO dose of 0.1 mM, lymphocytes were sensitized to additional exposures of NA-AAF, so that cytotoxicity was increased to 40% compared with 5% for the controls even though UDS was unaffected.

It is concluded that EO was toxic to lymphocytes, even when they were sensitized at non-toxic EO doses to the cytotoxic action of other mutagens (e.g. NA-AAF), and the cells that did survive above 2 mM EO were inhibited in their DNA-repair capacity as judged by reduced UDS.

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In vivo and in vitro ethylene oxide exposure of human lymphocytes assessed by chemical stimulation of unscheduled DNA synthesis

Abstract

Toxicol. Appl. Pharmacol.

Mutation Res.

Environmental Res.

Mutation Res.

Separation of leukocytes from blood and bone marrow

Scand. J. Clin. Lab. Invest.

Monitoring and risk assessment by means of alkyl groups in hemoglobin in persons occupational exposed to ethylene oxide

J. Environ. Pathol. Toxicol.

On the mutagenic action of ethylene oxide and diepoxybutane in barley

Hereditas

Evaluation of genetic risks of alkylating agents: Tissue doses in the mouse from air contaminated with ethylene oxide

Mutation Res.

Leukemia in workers exposed to ethylene oxide

J. Am. Med. Assoc.