A mortality study among workers in a French aluminium reduction plant

Objective: A mortality study on the association between lung cancer and occupational exposure to polycyclic aromatic hydrocarbons (PAHs) was carried out in a French aluminium reduction plant. This study updated a previous mortality study. Method: The historical cohort included every male worker who had been employed in the plant for at least 1 year between 1950 and 1994. Workers were followed-up for mortality from 1968 to 1994. Causes of death were obtained from death certificates. Standardised mortality ratios (SMRs) and 95% confidence intervals (CI) were computed using regional mortality rates as external reference to compare observed and expected numbers of deaths, adjusted for gender, age and calendar time. Results: The cohort comprised 2,133 men, of whom 335 died during the follow-up period. The observed mortality was lower than expected for all causes of death (SMR=0.81, CI 0.72–0.90) and for lung cancer (observed=19, SMR=0.63, CI 0.38–0.98). No lung cancer excess was observed in workshops where PAH exposure was likely to have occurred, and no trend was observed according to duration of exposure and time since first exposure. This low lung cancer mortality could be partly explained by a marked healthy worker effect and a possible negative confounding by smoking. An excess was observed for bladder cancer (observed=7, SMR=1.77, CI 0.71–3.64) in the whole cohort, that was higher among workers employed in workshops where PAH exposure was likely to have occurred (observed=6, SMR=2.15, CI 0.79–4.68). In addition, an SMR higher than unity was observed for “psychoses and neuro-degenerative diseases” (observed=6, SMR=2.39, CI 0.88–5.21), that could not be related to occupational aluminium exposure. Conclusion: No lung cancer risk was detected. Non-significant excesses were observed for bladder cancer and for psychoses and neuro-degenerative diseases. Received: 11 June 1999 / Accepted: 22 January 2000     

Mortality due to asbestos-related causes among railway carriage construction and repair workers

The objective of this study was to further clarify the cancer risk associated with asbestos exposure in railway carriage construction and repair. The cohort included 734 subjects employed between 1 January 1945 and 31 December 1969. Vital status was ascertained at 31 December 1997. Mortality was investigated in the time span 1970-97. Forty-two subjects (6%) were lost to follow-up and eight causes of death (4%) could not be ascertained. The overall mortality was not above the expected value. Among neoplastic diseases, excesses were observed for lung ?tandardized mortality ratio (SMR) = 124; 90% confidence interval (CI) = 87-172; 26 obs), pleura (SMR = 1,327; CI = 523-2,790; 5 obs), larynx (SMR = 240; CI = 95-505; 5 obs), liver (SMR = 241; CI = 126-420; 9 obs), pancreas (SMR = 224; CI = 98-443; 6 obs) and multiple myeloma (SMR = 429; CI = 117-1,109; 3 obs). The observed excess of lung and pleural neoplasms can be causally related to asbestos exposure in the manufacture of railway carriages. A causal role of asbestos exposure in the raised SMRs from laryngeal and pancreatic neoplasms and multiple myeloma cannot be conclusively proven.     

Mortality among workers in an Italian cigarette factory

A cohort study was conducted to evaluate the mortality pattern among female and male workers in a cigarette factory. The study followed 972 female workers and 761 male workers with at least 6 months of cumulative employment from 1 January 1962 through 1 July 1996. Among women, mortality from all causes of death [standardized mortality ratio (SMR) = 0.9; 95% confidence interval (CI) = 0.8-1.1] and mortality from all malignant neoplasms (SMR = 1.1; CI = 0.9-1.3) were consistent with reference rates. Male workers had a significantly reduced overall mortality (SMR = 0.8; CI = 0.7-0.9), while mortality from all malignant neoplasms was as expected (SMR = 0.9; CI = 0.7-1.0). Among female workers the frequencies of deaths from diseases of nervous system (SMR = 2.0; CI = 1.1-3.4) and from non-Hodgkin's lymphoma (NHL) (SMR = 2.7; CI = 1.0-5.6) were elevated at a statistically significant level. No association between duration of employment and diseases of nervous system was observed. A higher risk for NHL, based on three deaths, was reported among female workers with 15 or more years of employment (SMR = 8.1; CI = 2.2-21.0). Although based on small numbers, the excess of NHL here reported suggests that potential exposure to foliar residues of pesticides should be thoroughly considered in tobacco manufacturing.     

Mortality among Finnish Sea Pilots 1956 85: A Retrospective Cohort Study

The National Board of Navigation in Finland employed 942 seapilots in 1956–85, during which time 262 of them died(SMR = 77, 95% Cl = 68–86). The male population in southwestFinland served as control. The causes of deaths were collectedfrom death certificates. The mortality rate for all cardiovasculardiseases and lung cancer was lower among sea pilots than inthe comparison population (SMR = 83, 95% = Cl 69–97 andSMR = 67, 95% Cl 37–97) while for ischaemic heart diseases,it was similar to that of the population as a whole (SMR = 96,95% Cl = 77–115). Health selection due to ischaemic heartdisease was seen in the lower mortality rates among young pilotswho started work in 1956–85. Otherwise, the slightly higherrates may indicate a possibility of adverse health effects ofsea piloting.     

Mortality and cancer incidence in Ontario glass fiber workers

BACKGROUND: In a previous cohort study of glass fiber manufacturing, we found a significant increase in lung cancer. This study extends the follow-up period. METHODS: We conducted a historical prospective study of 2557 men employed in producing glass wool. We obtained work histories, causes and dates of death, and date and site of cancer diagnoses. We computed standardized mortality and incidence ratios (SMR, SIR). RESULTS: The overall SMR for lung cancer was 163 (95% CI = 118-221). The SMR did not vary consistently by duration of employment and time since first employment. However, plant workers with >20 years' employment and >40 years since first exposure had an SMR for lung cancer of 282 (95% CI = 113-582). The SMR dropped with later date of first exposure, but the trend was non-significant. There was an unexpected overall increase in kidney cancer incidence. DISCUSSION: The increase in lung cancer is greater than in other cohorts of glass fiber workers. Since exposure data are lacking from the early years of the plant, we cannot state if the excess was due to glass fibers, other work exposures or other reasons.     

Acute and chronic liver toxicity resulting from exposure to chlorinated naphthalenes at a cable manufacturing plant during World War II

Historical records were used to reconstruct an outbreak of chloracne and acute liver toxicity due to chlorinated napthalene exposure at a New York State plant which manufactured “Navy cables” during World War II. A cohort mortality study was conducted of the population (n = 9.028) employed at the plant from 1940 to 1944. Vital status followed through December 31, 1985. The study found an excess of deaths from cirrhosis of the liver [observed (OBS) = 150; standardized mortality ratio (SMR) = 1.84; 95% confidence interval (CI) = 1.56-2.16]; cirrhosis deaths were elevated to a similar degree in the 460 individuals who had chloracne (OBS = 8; SMR = 1.51; CI = 0.65-2.98). The SMR for “non-alcoholic cirrhosis” (OBS = 83; SMR = 1.67; CI = 1.33-2.07) was similar to the SMR for “alcoholic cirrhosis” (OBS = 59; SMR = 1.96; CI = 1.49-2.53). There was no evidence for increased alcoholism in the overall cohort based on mortality from alcohol-related causes of death other than cirrhosis (SMR for esophageal cancel = 1.01 and for deaths from alcoholism = 0.99). We conclude that the excess mortality from cirrhosis of the liver observed in this cohort is due to the chronic effect of chlorinated naphthalene exposure. © 1996 Wiley-Liss, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

Mortality among firefighters from three northwestern United States cities.

To explore whether exposure among firefighters to fire smoke could lead to an increased risk of cancer, lung disease, and heart disease, the mortality of 4546 firefighters who were employed by the cities of Seattle and Tacoma, WA and Portland, OR for at least one year between 1944 and 1979 were compared with United States national mortalities and with mortality of police officers from the same cities. Between 1945 and 1989, 1169 deaths occurred in the study population and 1162 death certificates (99%) were collected. Mortality due to all causes, ischaemic heart disease, and most other non-malignant diseases was less than expected based upon United States rates for white men. There was no excess risk of overall mortality from cancer but excesses of brain tumours (standardised mortality ratio (SMR) = 2.09, 95% confidence interval (95% CI) 1.3-3.2) and lymphatic and haematopoietic cancers (SMR = 1.31, 95% CI = 0.9-1.8) were found. Younger firefighters (< 40 years of age) appeared to have an excess risk of cancer (SMR = 1.45, 95% CI 0.8-2.39), primarily due to brain cancer (SMR = 3.75, 95% CI 1.2-8.7). The risk of lymphatic and haematopoietic cancers was greatest for men with at least 30 years of exposed employment (SMR = 2.05, 95% CI 1.1-3.6), especially for leukaemia (SMR = 2.60, 95% CI 1.0-5.4).     

Mortality of United Kingdom oil refinery and petroleum distribution workers, 1951-1998

The mortality experienced by cohorts of 28 630 oil refinery workers and 16 480 petroleum distribution workers has been investigated. Study subjects were all those male employees first employed in the period 1946-1974 at one of eight UK oil refineries or at one of 476 UK petroleum distribution centres; all subjects had a minimum of 12 months employment with some employment after 1 January 1951. The observed numbers of cause-specific deaths were compared with expectations based on national mortality rates. The resultant standardized mortality ratios (SMRs) were significantly below 100 for all causes, in both oil refinery workers (observed, 9341; expected, 10 649.7; SMR = 88) and petroleum distribution workers (observed, 6083; expected, 6460.3; SMR = 94). Significantly elevated SMRs were shown in oil refinery workers for cancer of the gall bladder (observed, 24; expected, 14.0; SMR = 172), cancer of the pleura (observed, 38; expected, 15.0; SMR = 254) and melanoma (observed, 36; expected, 22.2; SMR = 162). Significantly elevated SMRs were not found in petroleum distribution workers for any site of cancer. SMRs for selected causes of death were calculated by period from commencing employment, by year of hire and by job type. The only findings that suggested the presence of an occupational cancer hazard were an excess of mesothelioma in oil refinery workers and an excess of leukaemia in petroleum distribution workers, both excesses occurring in long-term follow-up for workers first employed >30 years ago.     

Mortality among firefighters from three northwestern United States cities.

To explore whether exposure among firefighters to fire smoke could lead to an increased risk of cancer, lung disease, and heart disease, the mortality of 4546 firefighters who were employed by the cities of Seattle and Tacoma, WA and Portland, OR for at least one year between 1944 and 1979 were compared with United States national mortalities and with mortality of police officers from the same cities. Between 1945 and 1989, 1169 deaths occurred in the study population and 1162 death certificates (99%) were collected. Mortality due to all causes, ischaemic heart disease, and most other non-malignant diseases was less than expected based upon United States rates for white men. There was no excess risk of overall mortality from cancer but excesses of brain tumours (standardised mortality ratio (SMR) = 2.09, 95% confidence interval (95% CI) 1.3-3.2) and lymphatic and haematopoietic cancers (SMR = 1.31, 95% CI = 0.9-1.8) were found. Younger firefighters (< 40 years of age) appeared to have an excess risk of cancer (SMR = 1.45, 95% CI 0.8-2.39), primarily due to brain cancer (SMR = 3.75, 95% CI 1.2-8.7). The risk of lymphatic and haematopoietic cancers was greatest for men with at least 30 years of exposed employment (SMR = 2.05, 95% CI 1.1-3.6), especially for leukaemia (SMR = 2.60, 95% CI 1.0-5.4).     

Cancer and other mortality patterns among United States furniture workers

Cause specific mortality was investigated among 36,622 members of a national furniture workers' union who were first employed in unionised shops between 1946 and 1962. Overall mortality for each race and sex group was less than expected when compared with United States death rates (white men SMR = 0.8, black men SMR = 0.7, white women SMR = 0.8, black women SMR = 0.5); however, raised risks were observed among white men employed in specific types of furniture industries and followed up for 20 or more years after first employment. Lymphatic and haematopoietic cancers were significantly raised (SMR = 1.8) among wood furniture workers followed up for at least 20 years due to excess deaths from leukaemia (SMR = 2.0) and non-Hodgkin's lymphoma (SMR = 2.0). Mortality from acute myeloid leukaemia was particularly high in this group (SMR = 4.7) based on six observed cases. Metal furniture workers followed up for at least 20 years experienced a significant excess of all cancers combined (SMR = 1.6), with non-significant increases in cancers of the lung, stomach, and colorectum. This group also had non-significant excesses of liver cirrhosis, arteriosclerotic heart disease, and cerebrovascular disease. Nasal cancer was not found to be significantly raised in this cohort, though the average follow up period may not have been sufficient to detect an excess risk for this uncommon tumour.     

Cancer and other mortality patterns among United States furniture workers.

Cause specific mortality was investigated among 36,622 members of a national furniture workers' union who were first employed in unionised shops between 1946 and 1962. Overall mortality for each race and sex group was less than expected when compared with United States death rates (white men SMR = 0.8, black men SMR = 0.7, white women SMR = 0.8, black women SMR = 0.5); however, raised risks were observed among white men employed in specific types of furniture industries and followed up for 20 or more years after first employment. Lymphatic and haematopoietic cancers were significantly raised (SMR = 1.8) among wood furniture workers followed up for at least 20 years due to excess deaths from leukaemia (SMR = 2.0) and non-Hodgkin's lymphoma (SMR = 2.0). Mortality from acute myeloid leukaemia was particularly high in this group (SMR = 4.7) based on six observed cases. Metal furniture workers followed up for at least 20 years experienced a significant excess of all cancers combined (SMR = 1.6), with non-significant increases in cancers of the lung, stomach, and colorectum. This group also had non-significant excesses of liver cirrhosis, arteriosclerotic heart disease, and cerebrovascular disease. Nasal cancer was not found to be significantly raised in this cohort, though the average follow up period may not have been sufficient to detect an excess risk for this uncommon tumour.     

Short- and long-term mortality in a prevalent cohort of morbidly obese patients in Italy

Summary. Background: Morbid obesity has been associated with increased mortality. Aim of the study: We evaluated the risk of short- (2 years) and long-term (10 years) mortality in two consecutive series of Italian morbidly obese patients hospitalized in a Metabolic Unit. Methods: The vital status of 569 patients (435 females and 134 males, BMI 44.4 kg/m², age 46.1 years), first admitted for clinical treatment in two separate periods (1988 and 1996), was ascertained in 1999. Results: Twenty-seven deaths were identified and compared with expected deaths according to mortality rates in the Italian population, to estimate the standardized mortality ratio (SMR). In the first two years after admission only 3 deaths were observed and the SMR tended to be reduced (SMR = 0.5, 95 % CI 0.1–1.5). In contrast, the long-term follow-up showed a significantly elevated risk of death (SMR = 1.6, 95 % CI 1.1–2.4). Conclusions: The follow-up of this Italian prevalent cohort confirm that morbid obesity is associated with increased mortality. The observed SMR might have been attenuated by inclusion in our study of subjects with relatively good health conditions, who are possibly more representative of the general obese population than subjects affected by important obesity-related complications, observed in other studies. The excess risk was not evident in the first two years after clinical treatment. Received: 1 March 2002, Accepted: 13 June 2002     

Primary liver cancer, other malignancies, and mortality risks following porphyria: a cohort study in Denmark and Sweden.

Cancer incidence and mortality risks were evaluated in a combined cohort of patients who were hospitalized for porphyria in Denmark (1977-1989) and Sweden (1965-1983). Patients were identified by using population-based hospitalization registries. The unique individual identification numbers of 530 patients with porphyria cutanea tarda (PCT) and 296 with acute intermittent porphyria (AIP) were linked to the nationwide cancer and death registries. Among patients with both types of porphyria, the authors found small but significantly elevated risks of all cancers combined (PCT: standardized incidence ratio (SIR) = 1.7, 95% confidence interval (CI) 1.3-2.2; AIP: SIR = 1.8, 95% CI 1.1-2.8) due to pronounced excesses of primary liver cancer (PCT: SIR = 21.2, 95% CI 8.5-43.7; AIP: SIR = 70.4, 95% CI 22.7-164.3) and moderate increases in lung cancer (PCT: SIR = 2.9, 95% CI 1.5-5.2; AIP: SIR = 2.8, 95% CI 0.3-10.2). PCT patients had a significantly increased risk of mortality from liver cirrhosis (standardized mortality ratio (SMR) = 8.4, 95% CI 3.1-18.4) or chronic obstructive pulmonary disease (SMR = 3.1, 95% CI 1.1-6.7). The increased risk of primary liver cancer and the increased risk of mortality from cirrhosis of the liver are consistent with findings from previous clinical surveys, but the new observations of excess lung cancer and chronic obstructive pulmonary disease require confirmation.     

A mortality cohort study among workers in a graphite electrode production plant in Italy

Aims: To investigate mortality from cancer and other diseases among workers in a graphite electrode production plant in Italy.

Methods: A total of 1291 males actively employed between 1 January 1950 and 31 December 1989 who had worked at the plant for at least one year were studied. The follow up extended from 1950 to 1997. Standardised mortality ratios (SMR) and their 95% confidence intervals (CI) were computed using mortality rates for the Italian and regional male population.

Results: Excess mortality was observed for all causes (SMR 1.44, CI 1.32 to 1.56), all cancers (SMR 1.27, CI 1.07 to 1.50), liver cancer (SMR 4.19, CI 2.68 to 6.23), silicosis (SMR 66.39, CI 52.56 to 82.7), and cirrhosis and other chronic diseases of the liver (SMR 1.87, CI 1.31 to 2.59) in comparison with the national male population. When regional rates were used to calculate the number of expected deaths, SMRs remained higher for silicosis (SMR 57.32, 42.11 to 76.22), and liver cancer (SMR 2.57, 1.57 to 3.97). Mortality from silicosis was increased in workers hired at young ages (<25 years, SMR 81.79; 25–34 years, SMR 82.73), and in workers aged <45 at death (SMR 333.3, CI 159.8 to 613). Mortality from liver cancer increased threefold (SMR 3.11, CI 1.78 to 5.05) in workers with more than 10 years of employment at the plant during the manufacture of Karbate products.

Conclusions: Results support the association between excess mortality from silicosis and occupational exposure to siliceous sands experienced during graphite electrode manufacturing. The observed excess mortality from liver cancer is compatible, to some extent, with exposures that may have occurred during the manufacture of phenolic and furfuryl resins treated products, although a role of lifestyle factors and viral infections cannot be excluded.

     

Epidemiologic study of workers exposed to vinyl chloride in Porto Marghera: mortality update

The investigation describes mortality of vinyl chloride exposed workers in the Montedison-Enichem plant located in Porto Marghera, near Venice, Italy. A total of 1658 workers employed from start of production (1950), present in 1956 or successively hired until 1985, were followed up between 01.01.1973 and 31.07.1999, for a total of 41.037 person years at risk: 248 deaths were observed. Mortality from all causes compared with regional population was lower than expected, (SMR 0.75; 90% CI 0.68-0.83) and from all malignant neoplasms similar to expected (SMR 0.94; 90% CI 0.81-1.09). SMR for primary liver cancer was significantly increased (SMR 2.78 90% CI 1.86-4.14). In the first year since leaving employment observed mortality was significantly above the null value for all causes (SMR 2.76; 90% CI 1.94-3.91), all malignant neoplasms (SMR 1.89; 90% CI 0.97-3.92) and cardiovascular diseases (SMR 2.37; 90% CI 1.13-4.95). Mortality rates for liver angiosarcoma (6 cases) increased with latency (trend test x 2 (1df) = 25.20 p < 0.001) and cumulative exposure (trend test x 2 (1df) = 61.00 p < 0.001), there were no cases with duration of employment less than 12 years, latency less than 10 years and for cumulative exposure less than 2.379 ppm-years. Mortality rates for hepatocellular carcinoma (12 cases) and liver cirrhosis (20 cases) showed a similar pattern for cumulative exposure. Observed mortality from lung cancer was higher than expected among those workers whose only job title was bagger. In the analysis accounting for latency, age and calendar period the RR for only bagger was 2.31 (90% CI 1.15-4.61). Mortality pattern for all causes, all malignancies and cardiovascular disease increased by time since employment, as expected in presence of a particularly strong Healthy Worker Effect (HWE). These results and the increased SMR values during the first year since leaving employment indicate that workers were selected into employment on the basis of good health conditions and early selective removal of weaker ones followed. The study results confirm the causal relationship between VCM exposure and liver angiosarcoma, and add supplementary evidence in favour of a causal explanation of the excess risk for hepatocellular carcinoma and liver cirrhosis as well as lung cancer among only baggers.     

Mortality of workers at a plant manufacturing nickel alloys, 1958-2000

BACKGROUND: Excess risks of respiratory cancer have been demonstrated in some groups of nickel-exposed workers. It is clear, however, that not all forms of nickel exposure are implicated in these excess risks. Aim To determine whether occupational exposures received in the manufacture of nickel alloys lead to increased risks of cancer, in particular nasal cancer and lung cancer. METHODS: The mortality experienced by a cohort of 1999 workers employed at a plant manufacturing nickel alloys has been investigated. Study subjects were all those male workforce employees first employed in the period 1953-1992 who had at least 5 years employment with the company. Observed numbers of cause-specific deaths were compared with expectations based on national mortality rates. Standardized mortality ratios (SMRs) were calculated by period from commencing employment and by operating area of first job. In addition, rate ratios derived from Poisson regression and based on an internal standard were calculated by levels of duration of employment. RESULTS: SMRs were significantly below 100 for all causes (observed 557, expected 704.3, SMR 79), all neoplasms (observed 169, expected 209.4, SMR 81) non-malignant diseases of the respiratory system (observed 50, expected 73.0, SMR 69) and diseases of the circulatory system (observed 261, expected 335.5, SMR 78). Significantly elevated SMRs were not shown for any cause of death and mortality was below expectation for stomach cancer (observed 8, expected 16.0, SMR 50), lung cancer (observed 64, expected 73.6, SMR 87) and bladder cancer (observed 3, expected 8.0, SMR 38). There were no deaths from nasal cancer (expected 0.33). More detailed findings were unexceptional. CONCLUSIONS: The analyses did not suggest the presence of an occupational cancer hazard in the mortality experience of the cohort.     

Suicide among Indigenous Sami in Arctic Norway, 1970–1998

Suicide mortality was examined between 1970 and 1998 in a cohort of 19,801 persons categorized as indigenous Sami in Arctic Norway. Standardized mortality ratios (SMR) were calculated using the suicide rates of the rural population of Arctic Norway as reference. There was a significant moderate increased risk for suicide among indigenous Sami (SMR = 1.27, 95% Confidence interval (CI): 1.02–1.56). In the study period, 89 suicides occurred in the cohort (70 men and 19 women) with increased suicide mortality both for indigenous Sami males (SMR = 1.27; 95% CI: 0.99–1.61) and females (SMR = 1.27; 95% CI: 0.77–1.99). Significant increased suicide mortality was found for young Sami aged 15–24 for both males (SMR = 1.82; 95% CI: 1.13–2.78) and females (SMR = 3.17; 95% CI: 1.17–6.91). Significant increased suicide mortality was found for indigenous Sami males residing in Sami core area (SMR = 1.54; 95% CI: 1.04–2.20) and for indigenous Sami males not belonging to semi-nomadic reindeer herding (SMR = 1.30; 95% CI: 1.00–1.65). Clusters of suicides in Sami core area may explain the increased suicide mortality found in subgroups among indigenous Sami.     

Increased risk for lung cancer and for cancer of the gastrointestinal tract among Geneva professional drivers.

A historical prospective cohort study of 6630 drivers from the Canton of Geneva was carried out to evaluate mortality and incidence of cancer in this occupation. The study population was all men (of all vocations) who held in 1949 a special licence for driving lorries, taxis, buses, or coaches and all new licence holders in the period 1949-61. Men born before 1900 and those with only an ordinary driving licence were excluded. According to the occupation registered on their licence, the 6630 drivers were distributed into three groups: (1) professional drivers (n = 1726), (2) non-professional drivers "more exposed" to exhaust gas and fumes (this group included occupations such as vehicle mechanic, policeman, road sweeper; n = 712), and (3) non-professional drivers "less exposed," composed of all other occupations (n = 4192). The cohort was followed up from 1949 to December 1986 and the trace of 197 men (3%) was lost. Compared with the general population of the Canton of Geneva, professional drivers experienced significant excess risks, taking into account 15 years of latency, for all causes of death (standardised mortality ratio (SMR) 115, 90% confidence interval (90% CI) 107-123) and for all malignant neoplasms (SMR 125, 90% CI 112-140; standardised incidence ratio (SIR) 128, 90% CI 115-142). Cause specific analysis showed significant excesses for lung cancer (SMR 150, 90% CI 123-181; SIR 161, 90% CI 129-198), oesophageal cancer (SMR 183, 90% CI 108-291), stomach cancer (SMR 179, 90% CI 117-263; SIR233, 90% CI 156-336), rectal cancer (SMR 258, 90% CIU 162-392; SIR 200, 90% CI 127-300), and cirrhosis of the liver (SMR 145, 90% CI 104-198). Risk of lung cancer increased significantly with time from first exposure. Among non-professional drivers no significant excess risk was found except for lung cancer mortality among the "less exposed" group (SMR 121, 90% CI 103-140), and for incidence of lung cancer among the "more exposed" group (SIR 161, 90% CI 111-227). The possible casual relation between exposure to engine exhaust emissions and the increased risk for lung cancer and for cancer of the gastrointestinal tract found among professional drivers is discussed.     

Increased risk for lung cancer and for cancer of the gastrointestinal tract among Geneva professional drivers.

A historical prospective cohort study of 6630 drivers from the Canton of Geneva was carried out to evaluate mortality and incidence of cancer in this occupation. The study population was all men (of all vocations) who held in 1949 a special licence for driving lorries, taxis, buses, or coaches and all new licence holders in the period 1949-61. Men born before 1900 and those with only an ordinary driving licence were excluded. According to the occupation registered on their licence, the 6630 drivers were distributed into three groups: (1) professional drivers (n = 1726), (2) non-professional drivers "more exposed" to exhaust gas and fumes (this group included occupations such as vehicle mechanic, policeman, road sweeper; n = 712), and (3) non-professional drivers "less exposed," composed of all other occupations (n = 4192). The cohort was followed up from 1949 to December 1986 and the trace of 197 men (3%) was lost. Compared with the general population of the Canton of Geneva, professional drivers experienced significant excess risks, taking into account 15 years of latency, for all causes of death (standardised mortality ratio (SMR) 115, 90% confidence interval (90% CI) 107-123) and for all malignant neoplasms (SMR 125, 90% CI 112-140; standardised incidence ratio (SIR) 128, 90% CI 115-142). Cause specific analysis showed significant excesses for lung cancer (SMR 150, 90% CI 123-181; SIR 161, 90% CI 129-198), oesophageal cancer (SMR 183, 90% CI 108-291), stomach cancer (SMR 179, 90% CI 117-263; SIR233, 90% CI 156-336), rectal cancer (SMR 258, 90% CIU 162-392; SIR 200, 90% CI 127-300), and cirrhosis of the liver (SMR 145, 90% CI 104-198). Risk of lung cancer increased significantly with time from first exposure. Among non-professional drivers no significant excess risk was found except for lung cancer mortality among the "less exposed" group (SMR 121, 90% CI 103-140), and for incidence of lung cancer among the "more exposed" group (SIR 161, 90% CI 111-227). The possible casual relation between exposure to engine exhaust emissions and the increased risk for lung cancer and for cancer of the gastrointestinal tract found among professional drivers is discussed.     

Cohort mortality study of rubber and plastics product makers in Italy

A retrospective cohort mortality study was carried Out in 20industrial factories in the Local Health Unit Bologna Sud (EmiliaRomagna, Italy), where different rubber and plastics productswere manufactured. The cohort consisted of 925 subjects (578males and 347 females) employed for at least six months continuously;follow-up was between the beginning of operation of each factory,ranging between mid fifties and mid seventies, and 31 December1989. For those exposed more than one year cause specific StandardizedMortality Ratios (SMRs) were computed using regional rates forcomparison, 90% confidence intervals (Cl) were calculated assumingthe Poisson distribution. Among the 748 subjects employed formore than one year (457 males and 291 females) there were nolost to follow-up, 54 individuals were dead (41 males and 13females) and for three subjects the cause of death was unknown.The results showed that all causes mortality was above expectancyin the total cohort (SMR=123; 54 Obs; 90% Cl=97–154),among males (SMR=117; 41 Obs; 90% Cl=89–152) and females(SMR=143; 13 Obs; 90% Cl=85–228). Increased mortalityfor all malignant tumours was observed in the total cohort (SMR=150;25 Obs; 90% Cl=104–209) and for both genders. All ninelung cancer cases were observed among males, the SMR was equalto 218 and was statistically significant; seven cases occurredat duration of exposure less than 10 years and six at latencyup to 20 years. The interpretation in terms of causality ofthe present investigation is limited by the small number ofobservations and by exposure definition solely in terms of employmentin the study factories; nonetheless the results are indicatingthe existence, in this group of rubber and plastics productmakers, of an adverse health effect which deserve further investigation.