Anders Holmén

Gasoline pump mechanics had increased frequencies and sizes of micronuclei in lymphocytes stimulated by pokeweed mitogen

Fifteen gasoline pump mechanics and 15 controls were investigated with the lymphocyte micronucleus assay and also with differential count of leukocytes in the peripheral blood. The lymphocytes were stimulated with phytohemagglutinin and pokeweed mitogen in parallel cultures. The pump mechanics had increased frequencies and sizes of micronuclei in the pokeweed mitogen-stimulated cultures but not in those stimulated with phytohemagglutinin. The difference in effect between the 2 mitogens is probably due to an increased sensitivity of the B-lymphocytes to mutagens. The leukocyte count was significantly higher in the gasoline-exposed group. The effect of the occupational exposure was probably caused by the benzene content of the gasoline. The time-weighted average for 8 h was around 1 mg/m3 of benzene, but there were peak levels of 20 mg/m3.

Immune factors, dental amalgam, and low-dose exposure to mercury in Swedish adolescents

Occupational high-dose exposure to metallic mercury can cause immune disturbances in sensitive individuals. Whether low-dose exposure to inorganic mercury from dental amalgam has this effect in humans is one of the issues related to the concept of oral galvanism and is supported by results of animal studies. This study explored some cellular immune factors (B- and T-lymphocytes, T4, T8, monocytes, neutrophilic, eosinophilic, and basophilic granulocytes, and large unstained cells) and some humoral immune factors (immunoglobulins IgG, IgG1, IgG2, IgG3, IgG4, IgA, IgM, IgE, albumin, alfa-1-antitrypsin, orosomucoid, haptoglobin, and antinuclear antibodies) in 41 healthy 15-y-old schoolchildren. The relationship between these factors and amalgam fillings and mercury concentrations in plasma (P-Hg) were investigated. A low, but significant correlation (r = 0.40, p < .05) was found between the number of amalgam surfaces and the P-Hg values, which were low for both sexes (median value = 1.8 nmol/l). There was no significant influence of the number of amalgam surfaces or P-Hg on the immune factors tested, except random findings. The girls had significantly higher values of T8, IgG, and IgG1 than the boys.

Micronuclei and mitotic index in B-, T4- and T8-cells treated with mitomycin C and γ-irradiation

Abstract Lymphocytes were treated in vitro with mitomycin C and γ-radiation at different doses (0–250 nmol/1 and 0–2 Gy, respectively). After incubation in RPMI 1640 medium and stimulation with phytohemagglutinin for 72 h, the lymphocyte subgroups T4 (CD4), T8 (CD8) and B (CD19) were separated by an immunomagnetic method and analyzed for the presence of micronuclei. With mitomycin C the highest levels were found in T4- and B-cells. When micronuclei were induced by irradiation the T4-cells showed the highest frequencies and the B-cells the lowest. The outcome of B-cells with γ-irradiation was probably due to a pronounced cytotoxic reaction in this cell type, which could be measured as a decrease in mitotic index.

Increased frequencies of micronuclei in T8 lymphocytes of smokers

Micronucleus frequencies and mitotic indices were analyzed in B, T4, and T8 lymphocytes from 40 smokers and 42 non-smoking referents. The highest level of micronuclei was found in T4 cells followed by T8 and B cells. These differences were statistically significant. There were statistically significant linear correlations between the micronucleus frequencies of all three subsets. There was a statistically significant effect of smoking only in the T8 cells. Smoking also increased the number of neutrophilic granulocytes and lymphocytes in the peripheral blood. There was a statistically significant effect of age on the micronucleus frequencies in T4 and T8 lymphocytes. The mitotic indices did not have any effect on the micronucleus frequencies and they were not influenced by smoking, age or sex.

Does transurethral resection of a clinically benign prostate gland increase the risk of developing clinical prostate cancer? A 10‐year follow‐up study

Background. Theoretical considerations have raised the suspicion that transurethral resection of the prostate (TURP) may increase the risk of developing prostate cancer in clinically benign prostate glands. Previous studies have not shown an increased risk among men who had undergone TURP for benign prostatic hyperplasia compared with the risk in age‐matched control subjects. However, in all of these studies, all men with stage T1 prostate cancer in the TURP‐group were excluded, possibly creating a bias, because no similar exclusion could be made for the controls.

Micronuclei in lymphocyte subsets in relation to immune proteins and allergic disease.

This is an investigation of 54 boys and 23 girls with a median age of 19 years (range 18-22 years). The study group contained 12 boys and five girls with asthma and 23 boys and seven girls with allergic rhinitis. Sensitivity to pollen and furred animals were reported by 22 boys and eight girls and by 17 boys and six girls, respectively. The levels of serum immune proteins (IgA, IgE and IgG with subclasses, and IgM) were determined by immunological techniques. As a biomarker of chromosomal damages, the lymphocyte micronuclei was used. We analyzed the frequencies of micronuclei in 3000 B-lymphocytes and in equal numbers of T4- and T8-lymphocytes. The lymphocytes were separated by magnetic attraction in T4 (CD4), T8 (CD8) and B (CD19) fractions using Dynabeads(R). The most interesting finding of this investigation was that the three markers of atopic disease, asthma, hypersensitivity to pollen and IgE levels, associated significantly with increased frequencies of micronuclei in B-lymphocytes. There was also a relation between IgA and the frequency of micronuclei in B-cells. In an epidemiological study of 7000 individuals with allergic diseases, we have found an over-risk for lymphomas in the group with positive skin prick test. Hypothetically, we think that there may be a link between our present finding of an increased mutagenic activity and the lymphoma over-risk among individuals with allergic disease since most lymphomas stem from B-lymphocytes.

Acute glomerulonephritis, Henoch-Schönlein purpura and dental amalgam in Swedish children: a case-control study

The issue of adverse health effects from dental amalgam and the concurrent low-dose exposure to inorganic mercury have been scrutinized by several Swedish expert groups during the past years. Only rarely have amalgam fillings in children been related to health effects. Experimental studies in genetically disposed animals have shown that low doses of inorganic mercury can induce autoimmune glomerulonephritis. The present case-control study included 31 children with acute glomerulonephritis and 33 with Henoch-Schönlein purpura retrieved from an in-patient register for the period 1973-1992 at the county hospital in Halmstad, Sweden. The median age was 10 and 9 years, respectively, for the two diagnostic groups. Dental clinics reported amalgam burden of the patients during the year before the date of diagnosis. Corresponding data were obtained for three randomly selected controls for each case, drawn from the case records of the same dental clinics, with matching for age and sex. Odds ratios (95% confidence interval) were 1.42 (0.49, 4.11) for Henoch-Schönlein purpura, 0.59 (0.25, 1.38) for acute glomerulonephritis and 0.84 (0.40, 1.75) for both diseases combined. The results of this study did not indicate increased disease risk in relation to amalgam burden.