Document MGny5aQyqyGQvNyy7eOoZ3Q6M

motion Research, 240 (1990) 83-85 Elsevier MUTGEN 01507 -- O Z-9- Cytogenetic analysis of peripheral blood lymphocytes in workers exposed to vinyl chloride L. Hrivnak, 2. Rozinova, S. Korony and E. Fabianova Regional Institute of Hygiene, 975 56 Banska Bystrica (Czechoslovakia) (Received 21 February 1989) (Revision received 31 August 1989) (Accepted 4 September 1989) 83 Keywords. Vinyl chloride-exposed workers; Chromosomes; Peripheral blood lymphocytes; Lymphocytes. Peripheral blood; Chro mosomal aberrations Summary In the present study, the method of cytogenetic analysis of peripheral blood lymphocytes was used to examine 43 workers exposed to vinyl chloride monomer (average exposure 11.2 years) and 22 subjects lected from the same locality (control group). A total number of 8650 metaphases were analysed. All P togenetic parameters examined were increased in the exposed group as compared to the control group and 3 parameters, chromatid breaks, percentage of aberrant cells and breaks per cell, were significantly increased (P < 0.001). V Vinyl chloride monomer (VCM) is a basic com ponent for the production of polyvinylchloride (PVC). PVC, with an estimated yearly production of 16 million tonnes in 1980 (Groth et al., 1981), is in daily contact with the human population. In exposed workers VCM leads to an increased inci dence of angiosarcomas of the liver, brain tumours, malignancies of the haematopoetic system and cancer of the lungs (IARC, 1979; Buffer et al., 1979; Nicholson et al., 1975). Similar results were obtained in experimental animals (Suzuki, 1978, 1981). Increased frequencies of chromosomal aberra tions in exposed workers indicate that VCM has mutagenic effects in man (Ducatman et al., 1975; Correspondence: Dr. L. Hrivnak, Regional Institute of HyJte**n* 975 56 Banska Bystrica (Czechoslovakia). Kuierova et al.. 1979). We analysed the chro mosomes of peripheral lymphocytes of workers exposed to VCM. The maximum allowable con centration for VCM in Czechoslovakia is 10 mg/m3. Materials and methods The exposed group consisted of 43 workers (average age 34.4 + 8.5 years), with an average VCM exposure of 11.2 7.2 years. According to measurements at the work place during the last 6 months before the blood was sampled the VCM concentrations varied from 2 to 40.9 mg/m3. The 22 subjects of the control group had similar social habits and living environments, but they were not exposed to VCM or other known mutagenic agents. All subjects who had been ill or taken medicines (including X-ray examinations) during the previ ous 3 months were excluded. 5-1218/90/103.50 C 1990 Elsevier Science Publishers B.V. (Biomedical Division) ASI 00004941 84 TABLE 1 RESULTS OF CYTOGENETIC ANALYSIS OF PERIPHERAL BLOOD LYMPHOCYTES OF VCM-EXPOSED WORKERS Group N Age (years) Average exposure to VCM (years) Number of Chromosomal metaphases aberrations analysed B' B" E' G Percent of aberrant metaphases ($ AB.C) Breaks per metaphase (B/C) Exposed 43 34.4 8.5 11.2 7.2 4650 Control 22 40.3 8.2 - 2200 119 * 52 19 184 3.30 * 24 18 5 55 1.64 0.037 * 0.019 B'. chromatid breaks; B", chromosome breaks; E'. chromatid exchanges; G, gaps. * Pc 0.001. Peripheral blood lymphocytes were cultured according to Hungerford (1965). Heparinised blood (0.7 ml) was cultured for 48 h at 37 C in RPM1 medium (USOL, Prague), supplemented with 20% inactivated calf serum (USOL, Prague), antibiotics (penicillin, streptomycin, neomycin) and stimulated with phytohaemagglutinin (PHA, USOL, Prague). Colchicine (0.7 g/ml, Fluka) was added to the culture for the last 2 h of incubation. Cytological preparations were made using a routine protocol and the slides were stained with Giemsa. At least 100 metaphases with 46 centromeres were analysed per person for the presence of chromosomal aberrations. The following types of chromosomal aberra tions were recorded; chromatid breaks (B'), chro mosome breaks (B"), chromatid exchanges ('), gaps (G). Gaps were not considered aberrations. Differences between groups were statistically evaluated using the /-test. Relative frequencies were transformed by inverse trigonometric func- TABLE 2 PERCENT ABERRANT METAPHASES SMOKERS AND NON-SMOKERS ABC) IN tion (2 arc sin -JJ) because of their small values (Reisenauer, 1970; Draper and Smith, 1981). Results and discussion The results are summarized in Table 1. All aberration types were increased in the exposed group as compared to the control group. The differences were highly significant for chromatid breaks (B'), percentage of aberrant cells (% AB. C) and for breaks per cell (B/C) (P < 0.001). Table 2 shows the percentages of aberrant cells in the groups of exposed and control persons with respect to smoking habits. In both groups there was no difference between smokers and nonsmokers. The difference in aberrations given as % AB.C between non-smokers in the exposed and the control groups was highly significant (P < 0.001), with respect to the smokers the difference was significant (RcO.05). These data indicate that the main reason for the increased aberration frequencies is the exposure to VCM. Our data agree with the results of Geryk and ZudovA (1986) who reported 4.1% AB.C in VCMexposed workers. Acknowledgements Group * AB C * AB C smokers non-smokers We are grateful to Dr. T. Geist for his kind support. We thank Dr. E. Horvathova for her Exposed 3.3 1.09 3.45 1.04 * 3.23 1.12 * * useful medical advice and D. Knoppova for her A N 43 15 28 laboratory assistance. Range 1-6 2-5 1-6 Control N Range 1.64 0.9 22 0-3 1.73 0.76* 7 1-3 * P < 0.05; ** P< 0.001. 1.60 1.0 ** 15 0-3 References Buffer, A., S. Wood. C. Eiflcr, L. Suarez and D.J. Kjlian (1979) Mortality experience of workers in vinyl chloride monomer production plant, J. Occup. Med., 21, 19S-202. ASI 00004942 1 i Draper, N.R.. and H. Smith (1981) Applied Regression Analy sis, 2nd edn., John Wiley and Sons, New York. (Russian translation, Moscow, 1986). Ducatman. A., K. Hirshom and J.l. Sclikoff (1975) Vinyl chloride exposure and human chromosome aberrations. Mutation Res., 31. 163-165. Geryk, E., and Z. Zudova (1986) Vinyl chloride as occupa tional health hazard, Pracov. Lek.. 38, 1-8. Groth, D.H.. D.W. Lynch, WJ. Moorman. L.E. Slettler, T.R. Lewis, W.D, Wagner and Ch. Kommineni (1981) Pneumo coniosis in ammals exposed to poly(vrnyl) chloride dust. Environ. Health Perspect., 41, 71-81. Hungerford, DA. (1965) Leucocytes cultured from small inocula of whole blood and the preparation of metaphase chromosomes by treatment with hypotonic KC1, Stain Technol.. 40. 333-338. 85 1ARC (1979) Monographs Suppl., International Agency for Research on Cancer. Lyon. Kuierova, M., Z. PolivkovA and J. BAtora (1979) Mutagenni a karcinogenni uiinky vinylchloridu, Prac. Ldk.. 31, 249-252. Nicholson. W.J., E.C. Hammond, H. Seidman and IJ. Selikoff (1975) Mortality experience of a cohort of vinyl chloride workers, Ann. N.Y. Acad. Sci., 246, 225-230 Reisenauer. R, (1970) Methods of Mathematical Statistics and Their Application. SNTL. Prague, 239 pp. (in Czech). Suzuki, Y. (1978) Pulmonary tumors induced in mice by vinyl chloride monomer, Environ. Res., 16, 285-301. Suzuki. Y, (1981) Neoplastic and nonneoplasuc effects of vinyl chloride in mouse lung. Environ. Health Perspect., 41, 31-52. V ASI 00004943 1