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H Malker

Publications and source records attributed to H Malker.

At least 19 recordsLinked to original sources
PubMed2005

Risk of cancer after low doses of ionising radiation: retrospective cohort study in 15 countries.

OBJECTIVES: To provide direct estimates of risk of cancer after protracted low doses of ionising radiation and to strengthen the scientific basis of radiation protection standards for environmental, occupational, and medical diagnostic exposures. DESIGN: Multinational retrospective cohort study of cancer mortality. SETTING: Cohorts of workers in the nuclear industry in 15 countries. PARTICIPANTS: 407 391 workers individually monitored for external radiation with a total follow-up of 5.2 million person years. MAIN OUTCOME MEASUREMENTS: Estimates of excess relative risks per sievert (Sv) of radiation dose for mortality from cancers other than leukaemia and from leukaemia excluding chronic lymphocytic leukaemia, the main causes of death considered by radiation protection authorities. RESULTS: The excess relative risk for cancers other than leukaemia was 0.97 per Sv, 95% confidence interval 0.14 to 1.97. Analyses of causes of death related or unrelated to smoking indicate that, although confounding by smoking may be present, it is unlikely to explain all of this increased risk. The excess relative risk for leukaemia excluding chronic lymphocytic leukaemia was 1.93 per Sv (< 0 to 8.47). On the basis of these estimates, 1-2% of deaths from cancer among workers in this cohort may be attributable to radiation. CONCLUSIONS: These estimates, from the largest study of nuclear workers ever conducted, are higher than, but statistically compatible with, the risk estimates used for current radiation protection standards. The results suggest that there is a small excess risk of cancer, even at the low doses and dose rates typically received by nuclear workers in this study.

Dose-Response Relationship, Drug↗
PubMed2003

Pediatric spinal cord injury in Sweden; how to identify a cohort of rare events.

STUDY DESIGN: Register study enhanced and verified by medical records and personal interviews and examinations. SETTINGS: Sweden. OBJECTIVES: To define a method of identifying a study population of rare events. To point out the relative importance of every step, an example is given of identifying persons who sustained traumatic spinal cord injury (SCI) in childhood. METHODS: Cases were identified in seven steps that all needed to be fulfilled, from definition of selection criteria through combination of several data sources, to the use of several verification methods. RESULTS: Initial screening by registers identified 384 possible cases, which however were found by subsequent analysis to include a large number of incorrect cases. At completion of all analytic steps, 35 living cases could be fully verified and 14 deceased cases could be partially verified. CONCLUSIONS: Registers offer a practical initial source for study population identification. The screening of International Classification of Diseases codes defining SCI only included less than 30% of 'true' SCIs. Subsequently, further refinement and quality control is necessary in order to ensure validity. Such further verification is time-consuming, but nevertheless necessary in order to verify a true cohort.

Child↗
PubMed1995

Exposure to extremely low frequency electromagnetic fields and the risk of malignant diseases--an evaluation of epidemiological and experimental findings.

Epidemiological and experimental studies concerning extremely low frequency electromagnetic field exposure and malignant diseases published up to 1 July 1994 were evaluated to assess the possible carcinogenicity of electromagnetic fields and the scientific basis for environmental and occupational standard setting. We concluded that there are possible associations between (i) an increased risk of leukaemia in children and the existence of, or distance to, power lines in the vicinity of their residence, (ii) an increased risk of chronic lymphatic leukaemia and occupational exposure to low frequency electromagnetic fields and (iii) an increased risk of breast cancer, malignant melanoma of the skin, nervous system tumours, non-Hodgkin lymphoma, acute lymphatic leukaemia or acute myeloid leukaemia and certain occupations. There is no scientific basis for occupational or environmental standard setting for low frequency electric or magnetic fields.

Adult↗
PubMed1994

Electromyographic activity during typewriter and keyboard use.

This study investigated how ergonomic design influences neck-and-shoulder muscle strain, through keyboard assessment. Muscular activity was measured electromyographically (EMG) from six muscles in the forearm and shoulders of eight experienced typists using each of five different types of keyboard: one mechanical, one electromechanical, and one electronic typewriter; one personal computer/word processor (PC-XT) keyboard; and one angled at 20 degrees in the horizontal plane. The impact on muscular activity of using a palmrest was also studied. The mechanical typewriter induced a higher strain in the forearm and finger muscles than did the modern typewriters and keyboards. These induced no different strain on the neck-and-shoulder muscles, except for the right shoulder muscle, which was more active with the electronic typewriter than with the other machines. Using a palmrest did not decrease the strain on the muscles investigated. Use of the 'angled' PC-XT keyboard did not influence the measured muscular load on the forearm and finger muscles compared to typing on an ordinary PC-XT keyboard, but decreased the extensor muscular strain compared to the electronic typewriter.

Adult↗
PubMed1992

Malignant lymphoproliferative diseases in occupations with potential exposure to phenoxyacetic acids or dioxins: a register-based study.

The Swedish Cancer Environment Register (CER) is a linkage of census data (e.g., on occupations) with the Swedish Cancer Register. It has been used in different studies to generate hypotheses on occupational risk factors for malignant tumors. In this study the risk for malignant lymphoma and multiple myeloma in occupations with potential exposure to phenoxyacetic acids or other related substances were investigated. An increased standardized incidence ratio (SIR) of 1.3 for multiple myeloma was verified in farmers (no. of cases = 335). This finding applied to both sexes, and the SIR increased over successive time periods. Regarding malignant lymphoma an increased SIR of 1.2 was found in farmers (no. = 227) for the latest time period studied (i.e. 1979-1984). When non-Hodgkin's lymphoma was studied separately, an increased risk (SIR = 1.2) was found only in carpenters (no. = 149), whereas for Hodgkin's disease, sawmill workers (no. = 10) had an increased SIR of 2.1. Physicians also had an elevated risk for malignant lymphoma. A major shortcoming in register studies such as CER is that no individual exposure data on different agents are available. Lack of an association between an occupation and a specific malignant disease, therefore, may not be taken as evidence that persons within that occupation are not at increased risk for that disease.

Agricultural Workers' Diseases↗
PubMed1990

Risk for cancer of the urinary bladder among hairdressers in the Nordic countries.

Several studies have indicated an increased risk for cancer of the urinary bladder among hairdressers. In a Danish linkage between census data and cancer register data both male and female hairdressers have an elevated risk for bladder cancer. The risk for lung cancer is close to unity, indicating that occupational factors rather than smoking, may be responsible for the increased risk for bladder cancer among hairdressers. To evaluate this hypothesis we conducted a collaborative analysis of data from similar linkages in Finland, Norway, and Sweden. The combination of high risk for bladder cancer and low or no risk for lung cancer was not found in the other Nordic countries; however, statistically significant increased risks for both bladder and lung cancer were found among male hairdressers in both Norway and Sweden. The relative risks for bladder cancer were of the same magnitude as the relative risks for lung cancer.

Adolescent↗
PubMed1990

Occupational groups potentially exposed to silica dust: a comparative analysis of cancer mortality and incidence based on the Nordic occupational mortality and cancer incidence registers.

We have analysed mortality and cancer incidence data available in census-based record-linkage studies from the Nordic countries for males in occupational groups with potential exposure to silica dust. The study showed an excess lung cancer risk for foundry workers in all the Nordic countries, and also for miners in Sweden. These results are consistent with the findings of previous in-depth epidemiological studies. The lung cancer risk did not differ significantly from that of the respective national populations for males working in glass, porcelain, ceramics and tile manufacture, in excavation, and in stone quarries, sand and gravel pits. Stone cutters, who are probably not exposed to known lung carcinogens at the workplace but in some places to high concentrations of silica dust, showed a significant excess lung cancer risk in both Finland and Denmark.

Adult↗
PubMed1988

Pleural mesotheliomas and asbestos exposure in the pulp and paper industries: a new risk group identified by linkage of official registers.

Analysis of data obtained by linking the 1960 Swedish Census and the Swedish Cancer Registry has demonstrated an increased risk of pleural mesothelioma among pulp and paper workers. The present study was undertaken with the aim of revealing possible environmental risk factors. The work histories of the 25 cases identified earlier were reviewed. "Certain" or "probable" exposure to asbestos was found among 70% of these workers. The study illustrates how linkage of official registers can be used to identify new risk environments and encourage the establishment of preventive measures.

Asbestos↗
PubMed1987

Occupational cancer risk associated with the storage and bulk handling of agricultural foodstuff.

The cancer mortality experience of 2649 Swedish grain millers was followed during the period from 1961 to 1979. Although the overall cancer incidence was not elevated, the risk of primary liver cancer was significantly elevated for this group (standard incidence ratio = 238). The Swedish data is compared to the cancer mortality experience of workers in the Netherlands and the United States who are also involved in the bulk handling and storage of agricultural foodstuffs (e.g., peanuts, grains). The varying occupational exposures in this international comparison help establish etiologic hypotheses in the absence of comprehensive exposure information. Agents of potential concern include metabolic products of fungal contaminants (e.g., aflatoxins) and pesticides used to protect grain from insect infestation.

Agriculture↗
PubMed1987

Suicide patterns among physicians related to other academics as well as to the general population. Results from a national long-term prospective study and a retrospective study.

In the present study, we have followed a national cohort of physicians, academics and the general population (part of the compulsory census in 1960) for a period of 10 years and identified all cases of suicide during the period 1961-1970. Furthermore, we have carried out a retrospective study of suicides among the four major medical specialist groups (general practitioners, internists, psychiatrists and general surgeons) and compared these rates with other medical specialists. Results show an elevated standardized mortality ratio (SMR) for suicide among female physicians compared to other academics as well as to the general population. Furthermore, male doctors exhibit an elevated suicide rate only when compared to other academics. Among the various specialists, general surgeons alone exhibited a significantly elevated suicide rate. The study clearly shows that female physicians are more prone to suicide than most other women, but that male physicians are also at risk compared to other male academics. Furthermore, at least in Sweden, general surgeons, not psychiatrists, have the highest suicide rate of all physicians.

Adult↗
PubMed1987

Suicide among Swedish dentists. A ten-year follow-up study.

In the present study, we have followed a national cohort of dentists, academics, i.e. people with three or more years of post-high school education, and the general population for a period of ten years, and identified all cases of recognized suicide during the period 1961 to 1970. The aim of the study was to assess whether suicide rates are higher among dentists even after adjustment for socioeconomic factors. Results show an elevated standardized mortality ratio (SMR) for male dentists compared to other male academics. Female dentists did not exhibit any increased risk. It is suggested that enhanced interest should be given to the possible etiologic role of not only psychosocial factors but also to psychoorganic consequences of mercury exposure among dentists.

Adult↗
PubMed1986

Comparison of temporal changes in U.S. and Swedish lung cancer, 1950-51 to 1981-82.

A comparison was made of temporal changes in lung cancer risk for the U.S. white and Swedish populations from 1950-51 to 1981-82 with the use of both life-table- and cohort-specific proportional hazard models to illustrate different features of the time series. Marked differences were noted for the two populations; Swedish lung cancer risks were generally lower than those in the United States. Sex-specific analyses were conducted that showed that Swedish males had a mortality rate roughly half that for U.S. males over the entire period. In contrast, U.S. white female mortality rates, though roughly equal to those for Swedish females in 1950-51, experienced a relatively more rapid increase; their rates were double the Swedish rates by 1980. The factors contributing to these patterns, such as marked cohort differences in risk, are identified by the various stages of analysis.

Age Factors↗
PubMed1986

Silica dust and lung cancer: results from the Nordic occupational mortality and cancer incidence registers.

Autopsy studies of the relationship between silicosis and lung cancer have been mainly negative; but recent epidemiologic studies have indicated a positive association, and an excess lung cancer risk has been observed in some occupational groups with exposure to silica dust. For the further shedding of light on the possible association between silica dust and lung cancer, analysis was made on mortality and cancer incidence data available in census-based record linkage studies from the Nordic countries for males in occupational groups with potential exposure to silica dust. The study showed an excess lung cancer risk for foundry workers in all the Nordic countries and for miners in Sweden. These results were consistent with findings from previous in-depth epidemiologic studies. The lung cancer risk did not differ significantly from that of the respective national populations for males working in excavation; stone quarries; sand and gravel pits; and glass, porcelain, ceramic, and tile manufacture. Stonecutters, who are probably not exposed to known lung carcinogens at the workplace but in some places to high concentrations of silica dust, showed a significant excess lung cancer risk in both Finland and Denmark. Excess lung cancer risks furthermore were seen for Finish miners, for Finnish males in excavation work, and for Danish glassworkers.

Denmark↗
PubMed1985

Cancer among farmers. A review.

During the performance of routine tasks farmers may come in contact with a variety of substances, including pesticides, solvents, oils and fuels, dusts, paints, welding fumes, zoonotic viruses, microbes, and fungi. Because some of these substances are known or suspected carcinogens, the epidemiologic literature regarding cancer risks concerning farmers has been reviewed. Farmers had consistent deficits for cancers of the colon, rectum, liver, and nose. The deficits for cancer of the lung and bladder were particularly striking, presumably due to less frequent use of tobacco among farmers than among people in many other occupational groups. Malignancies frequently showing excesses among farmers included Hodgkin's disease, leukemia, non-Hodgkin's lymphoma, multiple myeloma, and cancers of the lip, stomach, prostate, skin (nonmelanotic), brain, and connective tissues. The etiologic factors that may contribute to these excesses in the agricultural environment have not been identified. Detailed, analytic epidemiologic studies that incorporate environmental and biochemical monitoring are needed to clarify these associations.

Adolescent↗