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Biomedical subjects

B Pannett

Publications and source records attributed to B Pannett.

At least 37 records · Page 2Linked to original sources
PubMed1996

Mortality of farmers and farmers' wives in England and Wales 1979-80, 1982-90.

OBJECTIVES: To examine the mortality patterns of male and female farmers and farmers' wives in England and Wales. METHODS: Information on all deaths in England and Wales at ages 20-74 during the periods 1979-80 and 1982-90 was obtained from the Office of Population Censuses and Surveys. Proportional mortality ratios (PMRs) and proportional cancer mortality ratios (PCMRs) were used to compare the mortality of farmers with that of the general working population, and of farmers' wives with wives of all working men. RESULTS: Farmers and farmers' wives had high mortality from accidents and suicide and from certain respiratory diseases. Mortality from hernia was also raised. Deaths from cancer were generally below expectations, but the PMR for prostatic cancer was 112 (95%CI 106-118). The PMRs and PCMRs for oesophageal cancer were significantly increased in male farmers from two counties where cider is produced. CONCLUSIONS: The occupational hazards of farming continue to be associated with excess mortality, and most of the risks extend also to farmers' wives. Action is needed to reduce deaths, particularly from accidents and suicide.

Accidents, Occupational↗
PubMed1996

Upper aerodigestive cancer in battery manufacturers and steel workers exposed to mineral acid mists.

OBJECTIVE: To assess the risk of cancer from inhalation of mineral acid mists. METHODS: A cohort study and nested case-control study of upper aerodigestive tumours were carried out in men employed since 1950 at two battery plants and two steel works in Britain. The cohort was identified from personnel records and included 2678 men with definite exposure to acid mists (mainly sulphuric acid), 367 with possible exposure, and 1356 who were unexposed. Mortality was compared with that in the national population by the person-years method. Cases of upper aerodigestive cancer were identified from death certificates and cancer registrations, and their exposure to acids was compared with that of age matched controls (five per case) from the same plant by conditional logistic regression. RESULTS: In follow up to 31 December 1993, 93% of men were traced, including 1277 who had died. Among the men definitely exposed to acid mists, overall mortality was less than in the national population (standardised mortality ratio (SMR) 0.92, 95% confidence interval (95% CI) 0.85-0.98) as was mortality from all cancers (SMR 0.92, 95% CI 0.79-1.05) and specifically from cancer of the larynx (SMR 0.48, 95% CI 0.01-2.70) and lung (SMR 0.98, 95% CI 0.78-1.22). A total of 15 incident or fatal cases of upper aerodigestive cancer were identified during follow up. When these men were compared with controls, risk was moderately increased in those who had worked for at least five years in jobs entailing exposures to sulphuric or hydrochloric acid in excess of 1 mg/m3 (OR 2.0, 95% CI 0.4-10). CONCLUSIONS: These findings are consistent with those from other studies which have indicated a hazard of upper aerodigestive cancer from acid mists. However, they indicate that any risk from exposures to sulphuric and hydrochloric acid below 1 mg/m3 is small.

Aerosols↗
PubMed1995

Differences in occupational mortality from pleural cancer, peritoneal cancer, and asbestosis.

OBJECTIVE: To assess whether the increased risk of disease related to asbestos in occupations from the construction and engineering industries applies equally to pleural cancer, peritoneal cancer, and asbestosis. METHODS: Analysis was based on deaths among men aged 20-74 in England and Wales during 1979-80 and 1982-90. (n = 1,656,096). Information about cause of death and the last full time occupation of decedents was derived from death certificates. Proportional mortality ratios (PMRs) by occupation were calculated for each of pleural cancer, peritoneal cancer, and asbestosis. RESULTS: Altogether, 2848 deaths were attributed to cancer of the pleura, 362 to cancer of the peritoneum, and 281 to asbestosis. When occupations were ranked according to PMRs from these diseases, striking differences were found. The category of construction workers which included laggers had the highest mortality from peritoneal cancer (PMR 990, 64 deaths), but a PMR of only 160 (77 deaths) for pleural cancer. In contrast, several occupations with much higher mortality from pleural tumours had no excess of peritoneal cancer. PMRs for asbestosis related more closely to those for peritoneal than pleural cancer. CONCLUSIONS: These findings suggest that the exposure-response relations for diseases related to asbestos are not all linear, and that risks of pleural mesothelioma may be underestimated by simple extrapolation from observations in cohorts with heavy exposure.

Adult↗
PubMed1995

Contrasting geographical distribution of mortality from pneumoconiosis and chronic bronchitis and emphysema in British coal miners.

To explore whether the characteristics of coal mine dust that predispose to chronic airways obstruction are the same as those associated with pneumoconiosis, mortality from the two disease was compared in coal miners in 22 counties of England and Wales during 1979-80 and 1982-90. The proportional mortality ratios (PMRs) for coal workers' pneumoconiosis varied from 135 (95% confidence interval (95% CI) 16-488) in Leicestershire to 3825 (95% CI 1538-7881) in South Glamorgan. The PMRs for chronic bronchitis and emphysema were consistently higher than those in other occupations, but showed much less geographical variation and did not correlate geographically with those for pneumoconiosis. These findings indicate that the pathogenetic mechanisms by which coal mine dust causes chronic bronchitis and emphysema depend on different features of the dust from those producing pneumoconiosis. Also, they suggest that current social security regulations in Britain, which require evidence of pneumoconiosis as a condition of compensation for chronic bronchitis and emphysema in coal miners, may discriminate unfairly against claimants from some regions.

Adult↗
PubMed1994

Lobar pneumonia: an occupational disease in welders.

We have used data from three analyses of occupational mortality for England and Wales to investigate a suspected hazard of pneumonia in welders. Mortality from the disease was consistently raised in welders aged 15-64, with standardised mortality ratios of 184 (95% CI 150-224) in 1959-63 and 157 (121-200) in 1970-72. Analysis of data for 1979-80 and 1982-90 showed that the increased risk is attributable mainly to an excess of pneumococcal and unspecified lobar pneumonia (proportional mortality ratio 255, 95% CI 192-332). No excess occurred in men above retirement age (65). A possible explanation of these findings is that welding fume reversibly increases the susceptibility of the lung to pneumonic infection. The observation of a similar mortality pattern in moulders and coremakers points to the metallic component of the fume as a possible culprit, but ozone or oxides of nitrogen could also be implicated. There are grounds for lobar pneumonia to be considered an occupational disease in welders.

Adolescent↗
PubMed1994

Retrospective assessment of exposure through modeling in a study on cancer risks among workers exposed to phenoxy herbicides, chlorophenols and dioxins.

OBJECTIVES: The study aimed at developing a model for the retrospective assessment of exposures in epidemiologic studies when little or no data on past exposures are available. METHODS: A deterministic model was developed for the level of exposure by industrial hygienists involved in an international study on cancer risks among phenoxy herbicide or chlorophenol manufacturing workers and pesticide sprayers. The general source-receptor model was used as the conceptual framework for the model. RESULTS: The model included variables related to job, the emission of chemicals, contact with chemicals, personal protection, and other relevant determinants of exposure. Cumulative dose indices were calculated from the duration of exposure (from the work histories) and the level of exposure (from the model). CONCLUSIONS: Deterministic modeling in complex exposure situations may provide more valid and reliable results than its conventional alternative, subjective assessment by an expert.

Chlorophenols↗
PubMed1993

Ethylene oxide: an assessment of the epidemiological evidence on carcinogenicity.

Mortality from cancer among workers exposed to ethylene oxide (EtO) has been studied in 10 distinct cohorts that include about 29,800 workers and 2540 deaths. This paper presents a review and meta-analysis of these studies, primarily for leukaemia, non-Hodgkin's lymphoma, stomach cancer, pancreatic cancer, and cancer of the brain and nervous system. The magnitude and consistency of the standardised mortality ratios (SMRs) were evaluated for the individual and combined studies, as well as trends by intensity or frequency of exposure, by duration of exposure, and by latency (time since first exposure). Exposures to other workplace chemicals were examined as possible confounder variables. Three small studies by Hogstedt initially suggested an association between EtO and leukaemia, but in seven subsequent studies the SMRs for leukaemia have been much lower. For the combined studies the SMR = 1.06 (95% confidence interval (95% CI) 0.73-1.48). There was a slight suggestion of a trend by duration of exposure (p = 0.19) and a suggested increase with longer latency (p = 0.07), but there was no overall trend in risk of leukaemia by intensity or frequency of exposure; nor did a cumulative exposure analysis in the largest study indicate a quantitative association. There was also an indication that in two studies with increased risks the workers had been exposed to other potential carcinogens. For non-Hodgkin's lymphoma there was a suggestive risk overall (SMR = 1.35, 95% CI 0.93-1.90). Breakdowns by exposure intensity or frequency, exposure duration, or latency did not indicate an association, but a positive trend by cumulative exposure (p = 0.05) was seen in the largest study. There was a suggested increase in the overall SMR for stomach cancer (SMR = 1.28, 95% CI 0.98-1.65 (CI 0.73-2.26 when heterogeneity among the risk estimates was taken into account)), but analyses by intensity or duration of exposure or cumulative exposure did not support a causal association for stomach cancer. The overall SMRs and exposure-response analyses did not indicate a risk from EtO for pancreatic cancer (SMR = 0.98), brain and nervous system cancer (SMR = 0.89), or total cancer (SMR = 0.94). Although the current data do not provide consistent and convincing evidence that EtO causes leukaemia or non-Hodgkin's lymphoma, the issues are not resolved and await further studies of exposed populations.

Ethylene Oxide↗
PubMed1993

A cohort study of workers exposed to formaldehyde in the British chemical industry: an update.

A cohort study of workers exposed to formaldehyde in the British chemical industry in any one of six factories has been extended after the earlier published report in 1984. A further eight years of follow up to the end of 1989 have been included for the originally reported 7660 workers first employed before 1965, and a first follow up to the same date has been carried out for 6357 workers first employed since 1964. Extensive checking of the database has taken place including records at the factories, the MRC Environmental Epidemiology Unit, and the National Health Service Central Register. The updated findings include one death from nasal cancer compared with 1.7 expected in this number of men during the follow up period--which gives no support to the original hypothesis based on animal experimental data that formaldehyde may be a nasal carcinogen in humans. There have been no cases of nasopharyngeal cancer in the cohort compared with an estimated 1.3 expected--which gives no support to the findings in a similarly designed study in the United States of an excess of cancers of the nasopharynx associated with exposure to formaldehyde. There has been a slight excess of about 12% for lung cancer with 402 deaths compared with about 359 expected. This is similar to that found in the United States study, but higher than we reported earlier before the checking procedures and extended follow up. Further analysis gives no definitive indication of this excess of lung cancer being clearly related to formaldehyde exposure, and the increase is within that generally thought consistent with possible confounding effects of cigarette smoking (although no data are available on this point).

Chemical Industry↗
PubMed1991

Mortality and incidence of cancer at four factories making phenoxy herbicides.

To assess the possible carcinogenicity of phenoxy herbicides and related chlorophenols and dioxins, the International Agency for Research on Cancer is coordinating an international collaborative study of workers exposed to these compounds in their production or use. Four British cohorts of chemical manufacturers which have been recruited to the survey are described. They comprise a total of 2239 men employed during 1963-85. These subjects were traced to 31 December 1987 through the National Health Service Central Register and the National Insurance Index, and their mortality compared with that in the national population. Two deaths were from non-Hodgkin's lymphoma with 0.87 expected. Both deaths occurred more than 10 years after first exposure to phenoxy compounds. One further non-Hodgkin's lymphoma was registered in a living subject with probable exposure to phenoxy compounds. No cases of soft tissue sarcoma or Hodgkin's disease were recorded. A nonsignificant excess of lung cancer (19 deaths observed, 14.2 expected) is probably attributable to chance or a confounding effect of smoking. In one cohort only there was increased mortality from circulatory disease (34 deaths observed, 20.4 expected). A nested case-control study did not point to any occupational cause for this excess, but further evaluation will be needed during continued follow up.

Cardiovascular Diseases↗
PubMed1989

Workers exposed to ethylene oxide: a follow up study.

A cohort study has been carried out of 2876 men and women with potential exposure to ethylene oxide. Subjects were identified from employment records at four companies that have produced or used ethylene oxide since the 1950s and at eight hospitals which have had ethylene oxide sterilising units since the 1960s. The cohort represents a substantial proportion of the British workforce with a history of occupational exposure to ethylene oxide. Industrial hygiene data were not available before 1977, but since then time weighted average exposures have been less than 5 ppm in almost all jobs and less than 1 ppm in many. Past exposures were probably somewhat higher. In contrast to some previous studies, no clear excess of leukaemia (three deaths observed, 2.09 expected) and no increase in stomach cancer (five deaths observed, 5.95 expected) were found. This discrepancy with earlier reports may be due in part to differences in levels of exposure. Total cancer mortality was similar to that expected from national and local death rates. Some specific cancers showed small excesses but their relevance to ethylene oxide exposure is doubtful. Again, contrary to some earlier reports, no excess of cardiovascular disease was found. This study does not exclude the possibility that ethylene oxide is a human carcinogen but suggests that any risk of cancer from currently permitted occupational exposures is small.

Cardiovascular Diseases↗
PubMed1989

Lung cancer in the meat industry.

Routine statistics of occupational mortality and incidence of cancer have consistently shown high rates of lung cancer in butchers. Possible explanations include infection by carcinogenic papilloma viruses, exposure to polycyclic aromatic hydrocarbons and nitrites in the preservation of meat, or a confounding effect of tobacco. To explore these possibilities, we have examined the mortality of 1610 men employed at three British companies processing pork, beef, lamb, bacon, and other meat products. The overall death rate was less than in the national population (271 deaths observed, 310 expected) but there was an excess of deaths from cancer (87 observed, 80 expected), and in particular from lung cancer (42 observed, 32 expected). The risk of lung cancer was concentrated in subjects exposed to recently slaughtered meat, especially after an interval of 10 or more years. These findings increase suspicions of a risk of lung cancer in butchers, although further information is needed about smoking habits in the meat industry. If there is a hazard infection by a papilloma virus would seem the most likely cause.

Abattoirs↗
PubMed1988

Lung cancer among glass fibre production workers: a case-control study.

A cohort study among 4734 employees at an English glass fibre plant previously reported no excess of lung cancer mortality either overall or when examined in broad occupational groups. To investigate occupation in more detail, and to test the hypothesis that processes producing or using finer (respirable) fibres may be related to a higher risk of lung cancer, a nested case-control study has now been carried out. Included are 73 cases of lung cancer and 506 matched controls, for whom jobs held and processes worked on have been blindly recorded in more detail than for the cohort study. Workers known to have been employed on processes containing respirable fibres had a relative risk of lung cancer of 1.2 (95% confidence interval 0.7-2.0) compared with other workers. There was no evidence of a relationship of lung cancer to fibre diameter, duration of exposure, or time since first exposure. The results by broad occupational group were similar to those of the cohort study, and although some of the many detailed occupational categories examined had significantly raised relative risks, these did not appear to be related to exposure to respirable glass fibre. Although the study has not indicated a differential risk of lung cancer among workers exposed to finer diameter glass fibres, the exposure levels were low and the number of cases small.

Chemical Industry↗
PubMed1987

Mortality of workers exposed to styrene in the manufacture of glass-reinforced plastics.

Epidemiologic studies have suggested an increased risk of leukemia and lymphoma among workers exposed to styrene. In a further exploration of this possible hazard, an analysis was conducted of the mortality among 7,949 men and women employed during 1947-1984 in eight British companies manufacturing glass-reinforced plastics. The subjects were identified from company files and traced to the end of 1984 through National Health Service and National Insurance records. The overall mortality in the cohort was less than in the national population (693 deaths observed, 830.1 expected) as was mortality from cancer (181 deaths observed, 223.7 expected). In particular, there was a deficit of deaths from lymphoid and hemopoietic cancer (6 observed, 14.9 expected). The small excess of lung cancer (89 deaths observed, 80.1 expected) was not statistically significant and can probably be attributed to chance. Among 3,494 hand laminators (the job with the highest exposure to styrene) there was one death from lymphoma and none from leukemia. The findings do not exclude the possibility that styrene is a human carcinogen, but give no support to the hypothesis that it causes leukemia and lymphoma.

Female↗
PubMed1986

Follow up study of workers manufacturing chrysotile asbestos cement products.

A cohort study has been carried out of 2167 subjects employed between 1941 and 1983 at an asbestos cement factory in England. The production process incorporated the use of chrysotile asbestos fibre only, except for a small amount of amosite during four months in 1976. Measured airborne fibre concentrations available since 1970 from personal samplers showed mean levels below 1 fibre/ml, although higher levels had probably occurred previously in certain areas of the factory. No excess of lung cancer was observed in the mortality follow up by comparison with either national or local death rates, and analyses of subgroups of the workforce by job, exposure level, duration of employment, duration since entry, or calendar years of employment gave no real suggestion of an asbestos related excess for this cause of death. There was one death from pleural mesothelioma and one with asbestosis mentioned as an associated cause on the death certificate, but neither is thought to be linked to asbestos exposure at this factory. Other suggested asbestos related cancers, such as laryngeal and gastrointestinal, did not show raised risks. Although the durations of exposure were short in this study, the findings are consistent with two other studies of workers exposed to low concentrations of chrysotile fibre in the manufacture of asbestos cement products which reported no excess mortality.

Asbestos↗
PubMed1986

A survey of cancer and occupation in young and middle aged men. I. Cancers of the respiratory tract.

In a search for clues to previously industrial carcinogens the occupational and smoking histories of young and middle aged men with different types of cancer were compared. The study population comprised men aged 18-54 and resident in the counties of Cleveland, Humberside, and Cheshire (including the Wirral). From hospital and cancer registration records 2942 members of the study population in whom cancers were diagnosed during the period 1975-80 were identified retrospectively. The occupational and smoking histories of these patients were sought by a postal questionnaire addressed either to the patients themselves or, if they had died, to their next of kin. The overall response rate to the questionnaire was 52.1%. Additionally, limited occupational information was obtained for 89% of cases from their hospital notes. Analysis of these data suggests that no serious bias arose as a consequence of the incomplete response to the questionnaire. This paper concentrates on the results for cancers of the respiratory tract and mesothelioma. Mesothelioma was found to cluster in laggers, electricians, and shipyard workers, and nasal carcinoma in woodworkers. Carcinomas of the larynx and of the bronchus were examined by formal statistical techniques, each being compared with a control group made up of all other cancers combined. Several interesting occupational and industrial associations were shown, in particular, an excess of bronchial carcinoma in the leather industry (RR = 2.6, CI 1.2-6.0), in building labourers (RR = 1.7, CI 1.0-2.9) and other construction workers (RR = 1.8, CI 1.0-3.0), in bakers and pastry cooks (RR = 3.6, CI 1.3-10.4). and in cooks (RR = 2.5, CI 1.2-5.1). In addition, a small cluster of lung tumours was observed in men who had worked as dental mechanics.

Adolescent↗
PubMed1986

A survey of cancer and occupation in young and middle aged men. II. Non-respiratory cancers.

In a search for clues to previously unrecognised industrial carcinogens the occupational and smoking histories of young and middle aged men with different types of cancer have been compared. The study population comprised men aged 18-54 and resident in the counties of Cleveland, Humberside, and Cheshire (including the Wirral). Within this population 2942 patients in whom cancers were first diagnosed during the period 1975-80 were identified retrospectively from hospital and cancer registration records. Lifetime occupational and smoking histories were then sought from these subjects (or if they had died by proxy from their next of kin), using a postal questionnaire. The overall response rate was 52.1%. Analysis of limited occupational data obtained from the hospital notes of 89% of the patients suggests that no serious bias arose from the incomplete response to the questionnaire. The present paper describes the findings for non-respiratory cancers. Some tumours did not occur with sufficient frequency to warrant formal statistical analysis. Nevertheless, examination of the histories of patients with these cancers showed several interesting occupational clusters. In particular, five out of 29 patients with acute myeloid leukaemia had worked in electrical trades. The more common cancers were studied by statistical techniques. A large number of possible occupational associations were examined, and some will probably have achieved conventional levels of statistical significance by chance. The results should therefore be interpreted with caution, taking into account evidence from other studies and the biological plausibility of suggested hazards. Among the more interesting findings were an excess of bladder cancer in lorry drivers (RR=1.6, CI 1.0-2.4) and in men employed in the manufacture of vegetable and animal oils and fats (RR = 4.8, CI 1.8-12.9).

Adolescent↗
PubMed1986

Mortality of workers exposed to 2 methyl-4 chlorophenoxyacetic acid.

The authors examined the mortality and cancer incidence of employees at a company which has manufactured, formulated, and sprayed 2 methyl-4 chlorophenoxyacetic acid (MCPA) and other phenoxy acid herbicides. Ninety-eight percent of the 5,784 men employed by the company during 1947-1975 was traced to the end of 1983. The overall mortality of the cohort was less than that of the national population, as was mortality from cancer. When allowance was made for rural residence, the deficit of cancer deaths became a slight excess, but not statistically significantly so. Among workers whose jobs entailed potential exposure to MCPA, there was one death from soft tissue sarcoma (0.6 expected). No further cases of soft tissue sarcoma were registered among living members of the cohort. Three potentially exposed workers died from nasal carcinoma, but this tumor has not previously been associated with phenoxy herbicides and the cluster of cases may have occurred by chance. The findings do not exclude the possibility that MCPA is a human carcinogen, but they suggest that any risk of soft tissue sarcoma is less than that indicated by earlier studies of 2,4,5-T (2,4,5-trichlorophenoxyacetic acid) and 2,4,5-trichlorophenol and is small in absolute terms.

2-Methyl-4-chlorophenoxyacetic Acid↗