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Biomedical subjects

L Hardell

Publications and source records attributed to L Hardell.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Do flame retardants increase the risk of non-Hodgkin lymphoma? The levels of polybrominated diphenyl ethers are increasing in the environment].

Adipose tissue levels of tetra-BDE (2,2',4,4' tetra-brominated diphenyl ether) were measured in 42 male or female cancer patients [19 with non-Hodgkin's lymphoma (NHL), 23 with malignant melanoma (MM)], and in 27 controls without a diagnosis of cancer. As compared with tetra-BDE concentrations in controls, those in the MM subgroup did not differ, but those in the NHL subgroup were higher. Subgrouping of the cancer patients by occupational categories showed professional car, bus and truck drivers (at possible risk of exposure to PBDEs used as flame retardants in vehicle manufacture) to have higher tetra-BDE levels than controls, but not computer operators (at possible risk of exposure to PBDEs used in VDUs). Due to the small size of the series, however, the results may solely be regarded as hypothesis-generating, and further studies are needed.

Adult↗
PubMed1998

Oral snuff, smoking habits and alcohol consumption in relation to oral cancer in a Swedish case-control study.

The use of oral snuff is a widespread habit in Sweden. We investigated whether the use of Swedish moist snuff leads to an increasing risk of oral cancer. Other risk factors such as smoking tobacco and alcoholic beverages were also investigated. Our study comprised 410 patients with oral cancer, from the period 1980-1989, and 410 matched controls. All subjects received a mailed questionnaire. The response rates were 96% and 91% for cases and controls, respectively. In the study, a total of 20% of all subjects, cases and controls, were active or ex-snuff users. The univariate analysis did not show any increased risk [odds ratio (OR) 0.7, 95% confidence interval (CI) 0.4-1.1] for active snuff users. We found an increased risk (OR 1.8, CI 1.1-2.7) for oral cancer among active smokers. Alcohol consumption showed the strongest risk for oral cancer. Among consumers of beer, an increased risk of 1.9 (CI 0.9-3.9) was found. Corresponding ORs for wine and liquor were 1.3 (CI 0.9-1.8) and 1.6 (CI 1.1-2.3), respectively. A dose-response effect was observed. Although not statistically significant, a multivariate analysis similarly suggested that the most important risk factors were beer and liquor consumption, followed by smoking.

Age Factors↗
PubMed1998

[A new study of patients with cancer in Umeå alternative medicine is no alternative].

A questionnaire study comprising 854 cancer patients in the Umeå health care region and covering the 10-year period, 1987-96, showed only a few cancer patients to use alternative medicine treatment for their disease. As compared with 19.4 per cent of 144 residents selected from the population register who answered the questionnaire in 1987, 16.8 per cent of the cancer patients reported using alternative treatments in 1987, 14.4 per cent in 1990, and 16.4 per cent in 1996. The commonest forms of alternative medicine used were chiropractic and acupuncture, and the majority of treatments were for pain in the muscles or musculoskeletal system.

Acupuncture Therapy↗
PubMed1998

Occupational exposures, animal exposure and smoking as risk factors for hairy cell leukaemia evaluated in a case-control study.

To evaluate occupational exposures as risk factors for hairy cell leukaemia (HCL), a population-based case-control study on 121 male HCL patients and 484 controls matched for age and sex was conducted. Elevated odds ratio (OR) was found for exposure to farm animals in general: OR 2.0, 95% confidence interval (CI) 1.2-3.2. The ORs were elevated for exposure to cattle, horse, hog, poultry and sheep. Exposure to herbicides (OR 2.9, CI 1.4-5.9), insecticides (OR 2.0, CI 1.1-3.5), fungicides (OR 3.8, CI 1.4-9.9) and impregnating agents (OR 2.4, CI 1.3-4.6) also showed increased risk. Certain findings suggested that recall bias may have affected the results for farm animals, herbicides and insecticides. Exposure to organic solvents yielded elevated risk (OR 1.5, CI 0.99-2.3), as did exposure to exhaust fumes (OR 2.1, CI 1.3-3.3). In an additional multivariate model, the ORs remained elevated for all these exposures with the exception of insecticides. We found a reduced risk for smokers with OR 0.6 (CI 0.4-1.1) because of an effect among non-farmers.

Adult↗
PubMed1998

Oral infections and dental factors in relation to oral cancer: a Swedish case--control study.

We investigated the role of oral infections, dentition and dental X-rays for oral cancer in a north Swedish population. This case-control study consisted of 410 cases with oral cancer for the period 1980-89 and 410 matched controls. All subjects received a mailed questionnaire. The response rates were 96% and 91% for cases and controls, respectively. The univariate analysis showed a statistically significant increased risk for oral cancer among individuals reporting problems with recurrent clinical oral infection (odds ratio (OR) 3.8). Separate analyses were made for groups with a clearly stated HSV-1 infection (OR 1.9) and highly suspected HSV-1 infection (OR 3.3) as reported by the subjects. Odds ratios were also calculated for infections in relation to tobacco and alcohol habits. For individuals reporting recurrent infection problems an increased risk was observed in every combination category. Dental factors such as different fillings, dentures and fixed prostheses showed no increased risks. Dental X-ray did not produce an increased OR either. A multivariate analysis suggested that the most important risk factors were oral infections followed by liquor consumption and active smoking.

Alcohol Drinking↗
PubMed1998

Some aspects of the etiology of non-Hodgkin's lymphoma.

In epidemiologic studies, non-Hodgkin's lymphoma (NHL) has been associated with exposure to chemicals such as phenoxyacetic acids; chlorophenols; dioxins; organic solvents including benzene, polychlorinated biphenyls, chlordanes; and immunosuppressive drugs. Experimental evidence and clinical observations indicate that these chemicals may impair the immune system. The risk is increased for NHL in persons with acquired and congenital immune deficiency as well as autoimmune disorders. Also, certain viruses have been suggested to be of etiologic significance for NHL. In some cases of NHL the common mechanism for all these agents and conditions may be immunosuppression, possibly in combination with viruses.

Dioxins↗
PubMed1998

Agent Orange in war medicine: an aftermath myth.

Since the late 1970s several epidemiological studies have appeared linking exposure to phenoxy herbicides or chlorophenols to some malignant tumors. Most of these compounds are contaminated with dioxins and dibenzofurans; for example, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a contaminant of 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), a component of Agent Orange which was sprayed in Vietnam during the war. The results of some of the epidemiological studies on cancer risks associated with exposure to these compounds have been manipulated and misinterpreted, particularly by the Australian Royal Commission on the Use and Effects of Chemical Agents on Australian Personnel in Vietnam. Furthermore, a book on Australian war history entitled Medicine at War, commissioned by the Federal Government, reiterates several of these misinterpretations, despite available contrary evaluations from Australian and U.S. authorities. These remarkable and confusing circumstances in the scientific process are considered also in the light of the recent classification of TCDD as carcinogenic to humans, Group 1, by a Working Group at the International Agency for Research on Cancer in Lyon, France.

2,4,5-Trichlorophenoxyacetic Acid↗
PubMed1998

Case-control study on risk factors for testicular cancer.

Occupational exposures were assessed in a case-control study on testicular cancer using self administered questionnaires. Answers were obtained for 148 (91%) cases and 314 (87%) controls. Of the cases 101 had seminoma and 47 had embryonal testicular cancer. Occupational plastics work yielded odds ratio (OR) 2.9 with 95% confidence interval (CI) 1.3-6.5. Increased risk was found for embryonal cancer regarding farming (OR 3.1; CI 1.03-9.1) and contact with farm animals (OR 3.3; CI 1.00-10.9), but not for seminoma. For all testicular cancer exposure to insects repellents, mostly containing N,N-diethyl-m-toluamide (DEET) gave OR 1.7; CI 1.03-2.8, with a dose-response effect. Somewhat increased risks were found for amateur radio operators (OR 2.2; CI 0.7-6.6), work with radar equipment (OR 2.0; CI 0.3-14.2) and engineers in electronics and telecommunication industry (OR 2.3; CI 0.8-6.7) based on few exposed subjects, however. Video display unit work gave OR 1.5; CI 0.98-2.3 and for exposure 480 working days (median number) the risk increased further to OR 1.8; CI 1.1-3.2. Because of low numbers of exposed subjects in some calculations some of these results might be spurious and need to be further studied.

Adult↗
PubMed1998

Concentrations of the flame retardant 2,2',4,4'-tetrabrominated diphenyl ether in human adipose tissue in Swedish persons and the risk for non-Hodgkin's lymphoma.

Concentrations of the flame retardant 2,2',4,4'-tetrabrominated diphenyl ether (2,2',4,4'-TeBDE) in the adipose tissue of 77 individuals from Sweden were determined. The subjects were recruited during the time period 1995-97 and encompassed both men and women ranging from 28 to 85 years in age. Of the subjects included, 19 patients had non-Hodgkin's lymphoma (NHL), 23 patients had malignant melanoma, 8 patients had other cancers or in situ changes, and 27 persons had no cancer diagnosis. The mean concentration of 2,2',4,4'-TeBDE was 5.1 ng/g lipid (range 0.6-27.5) for the 27 persons without malignancies. For NHL patients the mean concentration was 13.0 ng/g lipid (range 1.0-98.2). A nonsignificantly elevated risk with dose response was found for NHL when the cases and controls were compared in the two highest concentration groups (2.05-< 5.43 ng/g lipid and > or = 5.43 ng/g lipid) with the lowest group (< 2.05 ng/g lipid) yielding odds ratio (OR) 1.9 with 95% confidence interval (CI) 0.3-14 and OR 3.8, CI 0.7-26, respectively. The results for the patients with malignant melanoma did not differ from the controls.

Adipose Tissue↗
PubMed1998

Environmental and occupational aspects on the etiology of non-Hodgkin's lymphoma.

Immunosuppression, possibly in combination with viruses, could be a main etiologic mechanism for non-Hodgkin's lymphoma (NHL). Chemicals such as phenoxyacetic acids, chlorophenols, dioxins, organic solvents, polychlorinated biphenyls, chlordane, and immunosuppressive drugs have been associated with this disease. Also UV light and blood transfusion have been postulated to be risk factors. Conclusive evidence of a causal association with NHL is not established for all of these exposures, but experimental evidence and clinical observations indicate that all these exposures have in common that they may impair the immune system. Furthermore, acquired and congenital immune deficiency as well as autoimmune disorders increase the risk for NHL. In view of currently available evidence, the first priority for reducing morbidity due to NHL might be to take action against adverse chemical exposures as a measure that is more easily achievable than any other kind of prevention.

Carcinogens↗
PubMed1998

Case-control study on breast cancer and adipose tissue concentrations of congener specific polychlorinated biphenyls, DDE and hexachlorobenzene.

In a case-control study on 43 patients operated for invasive breast cancer (cases) and 35 patients operated for benign breast disease (controls) adipose tissue concentrations of polychlorinated biphenyls (PCBs), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) and hexachlorobenzene (HCB) were investigated. Approximately 10 g of breast tissue free from tumour was taken and frozen until analysis. No significant difference for the sum of non co-planar PCBs or DDE was found between cases and controls. For postmenopausal women the odds ratio (OR) was increased for co-planar PCB #77 > 4.5 pg/g lipid (OR = 5.8, 95% confidence interval (CI) = 0.8-42), PCB #126 > 145 pg/g lipid (OR = 2.2, 95% CI = 0.2-18), PCB #169 > 90 pg/g lipid (OR = 7.8, 95% CI = 0.6-96), and for HCB > 40 ng/g lipid (OR = 1.9, 95% CI = 0.4-7.2) adjusted for age and parity. The risk increased further for postmenopausal women with oestrogen receptor positive tumours yielding for PCB #77 adjusted OR 33 (95% CI 1.8-588), PCB #126 OR not calculable (no unexposed cases), PCB #169 OR 8.6 (95% CI 0.5-136) and hexachlorobenzene OR 7.1 (95% CI 1.1-45). Also for the sum of PCB > 1230 ng/g lipid adjusted OR increased to 1.8 (95% CI 0.4-7.3) whereas the results were similar for DDE.

Adipose Tissue↗
PubMed1997

Occupational exposure to polyvinyl chloride as a risk factor for testicular cancer evaluated in a case-control study.

Occupational exposures were assessed in a case-control study on testicular cancer using self-administered questionnaires. In total, answers were obtained for 148 (91%) cases and 315 (87%) controls. Of the cases, 101 had seminoma and 47 had embryonal testicular cancer. An increased odds ratio (OR) was found for exposure to polyvinyl chloride (PVC) yielding an OR of 6.6 (95% confidence interval, 1.4-32). The risk increased further if cases with self-reported cryptorchidism or orchitis were excluded. Six of the 7 exposed cases had seminoma. Exposure to other types of plastics did not significantly increase the risk of testicular cancer.

Adult↗
PubMed1997

No association between immunohistochemical expression of p53, c-erbB-2, Ki-67, estrogen and progesterone receptors in female papillary thyroid cancer and ionizing radiation.

An association has previously been reported between exposure to medical diagnostic ionizing radiation and papillary thyroid cancer in women. To further evaluate potential mechanisms in carcinogenesis, the expression of p53, c-erbB-2, as well as Ki-67, estrogen and progesterone receptors were analyzed by immunohistochemistry in 19 women exposed to X-rays and for comparison in nine women without such reported exposure. They all had papillary thyroid cancer. No difference was found between these groups. The results of this study showed that p53, c-erbB-2, Ki-67, estrogen and progesterone receptors are not involved in papillary thyroid cancer associated with exposure to medical diagnostic ionizing radiation.

Adult↗
PubMed1997

Sinonasal cancer and occupation. Results from the reanalysis of twelve case-control studies.

A pooled reanalysis of twelve case-control studies on sinonasal cancer and occupation from seven countries was conducted in order to study associations with occupations other than wood- and leather-related occupations. The pooled data set included a total of 930 cases (680 men and 250 women) and 3,136 controls (2,349 men and 787 women). All the studies included a detailed occupational history for cases and controls. Each job was coded using the same classifications for occupation and industry. Two approaches were used in the analysis: systematic analysis of occupations; a priori analysis using a preestablished list of occupations and industries. The results confirmed associations observed in several studies not included in this analysis. For agricultural workers, significant excesses were observed for squamous cell carcinoma among women (OR = 1.69) and men (OR = 3.72 for ten years or more of employment as an orchard worker), and adenocarcinomas among men (OR = 2.98 for ten years or more of employment). Associations with textile occupations were observed for adenocarcinoma among women (OR = 2.60) and squamous cell carcinoma among men (OR = 5.09 for fiber preparers, 3.01 for bleachers). Elevated risks for both histologic types were observed among men employed in food manufacturing (OR = 3.25, adenocarcinoma), or as food preservers (OR = 13.9, squamous cell carcinoma), and among men employed as cooks (OR = 1.99, squamous cell carcinoma). A positive association with squamous cell carcinoma was observed for male transport equipment operators (OR = 1.21), and also with adenocarcinoma for male motor-vehicle drivers (OR = 2.50). A number of other associations were observed in the systematic analysis.

Adenocarcinoma↗
PubMed1997

Occupation and occupational exposure to UV light as risk factors for hairy cell leukaemia evaluated in a case-control study.

To investigate the role of occupation as a risk factor for hairy cell leukaemia a case-control study on 121 male, hairy cell leukaemia (HCL) patients, and 484 controls matched for age and sex, was conducted. We found significantly elevated risk for HCL among building painters (OR, 5.7; 95% CI, 1.6-20.8; based on six cases and four controls) and construction workers (OR, 3.3; CI, 1.2-9.2; based on seven cases and eight controls). Farming has been suggested as a risk factor in HCL. In this investigation farmers had an OR of 1.2 (CI, 0.6-2.3) and farm workers an OR of 1.5 (CI, 0.8-2.8). However, having ever worked in farming yielded an OR of 1.8 (CI, 1.1-2.9). Having grown up mainly in a rural area gave an OR of 1.4 (CI, 0.9-2.4). UV light has been suggested as a risk factor for non-Hodgkin's lymphoma (NHL). To evaluate the impact of UV exposure, classification of occupations as indoor, outdoor or mixed indoor/outdoor was made. Outdoor and mixed outdoor/indoor work yielded ORs of 2.3 (1.0-4.9) and 1.6 (1.0-2.5), respectively. When the effect of outdoor/indoor or mixed indoor/outdoor work was analysed using a scoring system the OR was 2.0 (CI, 0.9-4.4) for farmers compared with 0.8 (CI, 0.3-1.9) among non-farmers in the highest scoring group. There was no clear correlation between socioeconomic status as defined by the Swedish Socio-Economic Classification (SEI), and the risk of HCL. As many comparisons were made, the possibility of associations occurring by chance can not be excluded.

Adult↗