Sister chromatid exchange and micronucleus frequency in human lymphocytes of 1,650 subjects in an Italian population: II. Contribution of sex, age, and lifestyle

Abstract

Sister chromatid exchange (SCE) and micronuclei (MN) analysis was carried out on 1,650 healthy individuals living in Pisa and in two nearby small cities, Cascina and Navacchio (Ca‐Na). The effect of smoking on SCEs was linearly correlated with the number of cigarettes per day, and an increase of 7.3% SCEs was detectable for as few cigarettes as 1–10/day. Ex‐smokers showed intermediate mean values of SCEs (8.09 ± 1.88) in comparison with never smokers (7.54 ± 1.61) and current smokers (8.45 ± 1.94). Mean values of SCEs of ex‐smokers decreased linearly with time of smoking cessation, reaching the mean values of never smokers within 8 years. The extent of SCE decrease was inversely proportional to the number of cigarettes previously smoked. No interaction between smoking habits and coffee or alcohol drinking on SCEs was observed. A borderline (P = 0.053) increase in mean SCE values in coffee drinkers (more than 3 cups/day) was found. The age effect on SCEs was remarkable in Ca‐Na, but not in Pisa donors. Job type was not associated with significant modification of mean values of SCEs. Multiple logistic regression analysis revealed a statistically significant association between the proportion of high frequency cells (HCF) outliers and coffee consumption. Age and sex appeared to be by far the most important variables associated with modifications in MN frequency, which increased by 0.04 and 0.02 per year in males and females, respectively. Children and young donors (age ≤ 40 years) showed lower MN frequency regardless of sex, whereas sex appeared to determine a significantly higher increase of MN only in females older than 40 years. In contrast, in males the MN rate by age tended to level off after the age of 30–50. MN frequencies of Pisa blue‐ and white‐collar workers were statistically significantly higher than in students (+0.71 and +0.55, respectively). Smoking did not determine any increase of MN frequency. A total lack of correlation (P = 0.913) between MN and SCEs was observed. Environ. Mol. Mutagen. 31:228–242, 1998 © 1998 Wiley‐Liss, Inc.

Treatment of Pregnant Women with a Betamimetic and Verapamil Increases the Micronuclei Frequency in Umbilical Cord Blood Lymphocytes

“…A number of published studies showed the same frequency of MN among males and females aged ≤ 19 years (Barale et al 1998;Shi et al 2000). Analyzing a pooled database of nearly 7000 subjects, Bonassi et al (2001) showed an effect of sexual differences of MN only in adults.…”

Instabilidade cromossômica induzida por agroquímicos em trabalhadores rurais na região de Passo Fundo, Rio Grande do Sul, Brasil

“…Em relação ao hábito de fumar, os presentes achados estão de acordo com aqueles encontrados por Kourakis et al (1992), que estudaram a freqüência de aberrações cromossômi-cas em linfócitos de 29 trabalhadores expostos a uma mistura de pesticidas, e não encontraram diferenças significativas entre fumantes e não fumantes. De modo semelhante, Barale et al (1998) analisaram materiais obtidos em culturas de linfócitos de 1.650 indivíduos italianos, e não encontraram relação entre o hábito de fumar e o aumento na freqüência de micronúcleos.…”

“…Esses resultados es- Barale et al (1998). Páldy et al (1987), além de observarem que a exposição a uma mistura de pesticidas pode produzir efeitos citogenéticos em células somáticas humanas, também verificaram uma tendência no aumento da taxa de aberrações cromossômicas com relação ao tempo de exposição, situada em torno de 11 a 15 anos, que decresce após 15 anos de exposição.…”

DNA Damage and Oxidative Stress in Patients with Chronic Obstructive Pulmonary Disease

“…The studies about smoker-induced DNA damage are contradictory and show that there is no difference between smokers and nonsmokers [25,26]. Others studies report unexpected negative results [27] and sometime smokers present lower DNA damage than non-smokers [28]. A few cigarettes per day may stimulate an adaptive response and a continued exposure to mutagens/carcinogens may induce resistance to further DNA damage [29].…”