Lung cancer mortality among workers making lead chromate and zinc chromate pigments at three English factories.

Lung cancer mortality among 1152 men working at three English chromate pigment factories was studied from the 1930s or 1940s until 1981. Workers at factory C were exposed only to lead chromate and experienced normal mortality (Obs/Exp deaths 7/6.45). Workers at factories A and B were exposed to both lead and zinc chromate; mortality was normal among those who had only low exposure (O/E 7/6.95). For workers with high or medium exposure lung cancer mortality was significantly raised among men remaining at least a year after entering service at factory A during 1932-54 (O/E 21/9.45) and at factory B during 1948-67 (O/E 11/2.50). At factory A, 1933-46 entrants staying only 3-11 months were not affected (O/E 6/5.04) and 1955-63 entrants also appeared unaffected (O/E 2/2.00); working conditions there improved in 1955. The hazard at factories A and B affected workers who left after one year as well as those with longer service, and latent intervals were unusually short. The results indicate that moderate or heavy exposure to zinc chromate may give rise to a severe risk of developing lung cancer, but that exposure which is relatively mild or lasts less than a year may not constitute an effective risk. The results provide no indication that lead chromate induces lung cancer in man, even under conditions conducive to lead poisoning.     

Lung cancer mortality among chromate production workers

Aims: To assess mortality in 1997 among 493 former workers of a US chromate production plant employed for at least one year between 1940 and 1972.

Methods: Cohort members were followed for mortality to 31 December 1997. Standardised mortality ratios (SMRs) were calculated for selected cause specific categories of death including lung cancer. Lung cancer mortality was investigated further by calculation of SMRs stratified by year of hire, duration of employment, time since hire, and categories of cumulative exposure to Cr(VI).

Results: Including 51 deaths due to lung cancer, 303 deaths occurred. SMRs were significantly increased for all causes combined (SMR = 129), all cancers combined (SMR = 155), and lung cancer (SMR = 241). A trend test showed a strong relation between lung cancer mortality and cumulative hexavalent exposure. Lung cancer mortality was increased for the highest cumulative exposure categories (1.05 to <2.70 mg/m³-years, SMR = 365; 2.70 to 23 mg/m³-years, SMR = 463), but not for the first three exposure groups. Significantly increased SMRs were also found for year of hire before 1960, 20 or more years of exposed employment, and latency of 20 or more years.

Conclusions: The finding of an increased risk of lung cancer mortality associated with Cr(VI) exposure is consistent with previous reports. Stratified analysis of lung cancer mortality by cumulative exposure suggests a possible threshold effect, as risk is significantly increased only at exposure levels over 1.05 mg/m³-years. Though a threshold is consistent with published toxicological evidence, this finding must be interpreted cautiously because the data are also consistent with a linear dose response.

     

Mortality study among workers producing chromate pigments in France

In a follow-up study of 294 men who had worked for at least 6 months in a chromate-producing factory in France between 1958 and 1987, only 16 were lost to follow-up and the number of person-years in the study was 5207. Occupational data were provided by the administration of the plant. The causes of deaths were ascertained from hospital and general practitioners' records. The observed numbers of deaths were compared with the expected numbers based on local rates with adjustment for age, sex and calendar time (standardized mortality ratio, SMR). The overall mortality did not differ significantly from that expected (SMR = 1.20, 95% CI = 0.98–1.47), whereas mortality due to lung cancer was in significant excess (SMR = 3.60, 95% CI = 2.13–5.68). Significantly higher lung cancer SMRs were found for workers whose duration of employment was more than 10 years. A non-significant excess was observed for all forms of digestive tract cancer (SMR = 1.30, 95% CI = 0.60–2.47). There were two cases of brain cancer when 0.24 was expected (SMR = 8.44, 95% CI = 1.02–30.49). No previous report has mentioned an association of brain cancer with chromate pigments; however, because of the small numbers involved, a chance excess should be considered.     

Lung cancer mortality among workers at a nuclear materials fabrication plant

BACKGROUND: The Oak Ridge, Tennessee Y-12 plant has operated as a nuclear materials fabrication plant since the 1940s. Given the work environment, and prior findings that lung cancer mortality was elevated among white male Y-12 workers relative to US white males, we investigated whether lung cancer mortality was associated with occupational radiation exposures. METHODS: A cohort of 3,864 workers hired between 1947 and 1974 who had been monitored for internal radiation exposure was identified. Vital status was ascertained through 1990. RESULTS: Over the study period 111 lung cancer deaths were observed. Cumulative external radiation dose under a 5-year lag assumption was positively associated with lung cancer mortality (0.54% increase in lung cancer mortality per 10 mSv, se=0.16, likelihood ratio test (LRT)=5.84, 1 degree of freedom [df]); cumulative internal radiation dose exhibited a highly-imprecise negative association with lung cancer mortality. DISCUSSION: The positive association between external radiation dose and lung cancer mortality was primarily due to exposure occurring in the period 5-14 years after exposure (0.97% increase in lung cancer mortality rate per 10 mSv, se=0.28, LRT=6.35, 1 df). The association between external radiation dose and lung cancer mortality was negative for exposures occurring at ages<35 years and positive for exposures occurring at ages 35-50 and 50+years. CONCLUSIONS: There is evidence of a positive association between cumulative external radiation dose and lung cancer mortality in this population. However, a causal interpretation of this association is constrained by the uncertainties in external and internal radiation dose estimates, the lack of information about exposures to other lung carcinogens, and the limited statistical power of the study.     

Long term mortality study of chromate pigment workers who suffered lead poisoning.

Long term mortality was studied in a group of 57 chromate pigment workers who suffered clinical lead poisoning, mostly between 1930 and 1945. One death was attributed to lead poisoning and there were significant excesses of deaths from nephritis (observed/expected 3/0.24) and cerebrovascular disease (9/2.20), as well as non-significant excesses for respiratory diseases (7/3.59) and accidents and violence (3/1.13). The deaths from nephritis followed long spells of service exceeding 10 years. Poisoning appeared to have more adverse long term effects on older workers: 15 men aged 40 or over at the time of acute poisoning experienced generally high mortality, and 30 years later or by the end of 1981 only two survived instead of the seven expected. The risk of cerebrovascular disease appeared to be unrelated to duration of exposure and affected even men employed for under one year. Excluding the 57 lead poisoned men, other contemporary workers at the factories showed no excess mortality from cerebrovascular disease.     

Lung cancer prevalence among shipyard workers

The prevalence of lung cancer has been ascertained during a survey of 286 shipyard workers all 20 to 45 years from onset of asbestos exposure in shipyard work. Two men had had previous thoracic surgery for lung cancer. In addition, bronchogenic carcinoma was found in five men. One was among the 35 men less than 30 years in the yard; three were in the 191 who had begun work 30 to 39 years before, and one was in the group of 60 men who were 40+ years from onset. The potential usefulness of large-scale surveillance programs for the early detection of lung cancer among current and former shipyard workers is discussed.     

Lung cancer among long-term steel workers

A case-control study in an industrialized area of eastern Pennsylvania involving interviews with the next of kin of 335 men who died of lung cancer and of 332 controls who died of other causes revealed a significantly increased risk associated with employment in the steel industry, the area's major employer. The excess was primarily among long-term employees, particularly those who began work before 1935. Adjusted for cigarette smoking, the odds ratio associated with career employment was 1.8 (p = 0.01, 95% confidence interval, 1.2, 2.8). The increase was higher among steel workers who worked in foundry operations, but was seen for broad categories of jobs within the industry. No significant associations were found for other industries, although a 60% increase (p = 0.27, 95% confidence interval, 0.7, 3.7) was noted for zinc smelter workers employed at least 15 years. The findings help clarify the role of occupation as a risk factor for lung cancer in the area, and suggest that exposures in the steel industry contribute to an extent greater than previously recognized.     

常熟市小型蓄电池厂148名铅作业工人的血铅与血液锌原卟啉水平调查

目的 了解铅作业工人血铅和血液锌原卟啉水平.方法 采集常熟市2家小型蓄电池厂148名铅作业工人静脉血,用石墨原子吸收法测定血铅,用AVIV206D锌原卟啉仪测定红细胞锌原卟啉.结果 148名铅作业工人血铅检测水平为0.65 ～ 3.61 μmol/L,超标者102人,超标率为68.92％;红细胞锌原卟啉检测水平为0.54～ 19.7 μmol/L,超标者66人,超标率为44.59％.铅作业男工人血铅和红细胞锌原卟啉含量有相关性,女工无相关性.结论 该市小型蓄电池厂由于铅污染严重,作业工人血铅和血液锌原卟啉检超标情况严重,监督部门要督促企业改进生产工艺和定期进行职业健康监护.     

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.     

Lung cancer mortality in the German chromate industry, 1958 to 1998

OBJECTIVES: We conducted a mortality study of two German chromate production facilities and evaluated possible dose-response relationships between hexavalent chromium exposure and lung cancer. METHODS: Mortality was followed-up through 1998 and limited to those employed since each plant converted to a no-lime production process. More than 12,000 urinalysis results of chromium levels were available, as was smoking information. RESULTS: All-cause mortality indicated a healthy worker effect (standardized mortality ratio [SMR] = 0.80, 95% confidence interval [CI] = 0.67-0.96); however, lung cancers appeared to be increased (SMR = 1.48, 95% CI = 0.93-2.25). No clear dose-response was found in stratified analyses by duration of employment and time since hire. On the basis of urinary chromium data, lung cancer risk was elevated only in the highest exposure group (SMR = 2.09, 95% CI = 1.08-3.65). CONCLUSIONS: These data suggest a possible threshold effect of occupational hexavalent chromium exposure on lung cancer.     

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.     

Lung function predicts mortality: 10-year follow-up after lung cancer screening among asbestos-exposed workers

Purpose

To assess the predictive value of lung function impairment on mortality among asbestos-exposed workers.

Methods

A total of 590 workers originally screened for occupational lung disease including spirometry and pulmonary diffusing capacity measurements were followed up for mortality data (ICD-10 classification). The mean follow-up time was 10.5 years. Associations of different lung function parameters with mortality from all causes and from cardiovascular (I00-I99) and non-malignant respiratory diseases (J00-J99) were analysed. Factor analysis was used to create obstructive and restrictive factors.

Results

A total of 191 deaths were found altogether. Most measured lung function variables were associated with increased mortality when studied separately. Both decreased forced expiratory flow in one second (hazard ratio/measurement unit = 0.977, 95 % CI 0.969–0.988, p < 0.001) and impaired diffusing capacity (0.973, 0.965–0.981, p < 0.001) were independently associated with mortality from all causes, as well as from cardiovascular and non-malignant respiratory diseases. Both obstructive factor alone and the sum of obstructive and restrictive factors were associated with all studied mortality categories. The restrictive factor alone was associated with all-cause and respiratory mortality.

Conclusions

Deteriorated lung function predicts deaths. The reasons for impaired lung function should be medically explored to enable restoring measures aiming thus to prevent premature deaths.     

Lung cancer among rock and slag wool production workers

BACKGROUND: Previous cohort studies have found an elevated risk of lung cancer among rock and slag wool (RSW) production workers. The aim of the present study was to investigate the risk of lung cancer associated with exposure to RSW while controlling for other occupational exposures and tobacco smoking. METHODS: Since 1971, a total of 196 lung cancer cases occurred among men who worked in seven plants in Denmark, Norway, Sweden, and Germany, with start of production between 1937 and 1950. We obtained information on occupational history and extra-occupational factors from either the subject or the next of kin for 133 cases and 513 matched controls. We assessed occupational exposure on the basis of interview data combined with information from expert panels set up in each factory. RESULTS: For cumulative exposure to RSW assessed with a 15-year lag, the smoking-adjusted odds ratios in the second, third, and fourth quartiles of exposure were 1.3 (95% confidence interval [CI] = 0.7-2.3), 1.0 (CI = 0.5-1.9), and 0.7 (CI = 0.3-1.3). Similar results were obtained when we included only those workers employed for more than 1 year, when we included other indicators of RSW exposure, and after control for co-exposures. CONCLUSIONS: This study provides no evidence of a carcinogenic effect on the lung of rock and slag wool under exposure circumstances in the production industry during the last four to five decades.