Mortality in the British printing industry: a historical cohort study of trade union members in Manchester

Oral Cavity Squamous Cell Carcinoma Risk Factors: State of the Art

Head and neck (HN) squamous cell carcinomas (SCCs) originate from the epithelial cells of the mucosal linings of the upper aerodigestive tract, which includes the oral cavity, the pharynx, the larynx, and the sinonasal cavities. There are many associated risk factors, including alcohol drinking coupled with tobacco use, which accounts for 70% to 80% of HNSCCs. Human papilloma virus (HPV) is another independent risk factor for oropharyngeal SCC, but it is only a minor contributor to oral cavity SCC (OSCC). Betel quid chewing is also an established risk factor in southeast Asian countries. However, OSCC, and especially oral tongue cancer, incidence has been reported to be increasing in several countries, suggesting risk factors that have not been identified yet. This review summarizes the established risk factors for oral cavity squamous cell carcinomas and examines other undemonstrated risk factors for HNSCC.

Prevalence of Acute Symptoms among Workers in Printing Factories

Objective. To identify socioeconomic situation factors and behavioral factors associated with the prevalence of acute symptoms among 150 printing workers in 16 printing factories in Southern Thailand. Materials and Methods. A cross-sectional study was conducted by interviewing 150 printing workers in 16 printing factories in Southern Thailand. Results. Acute symptoms comprised dizziness, drowsiness, eye irritation, light-headedness, rhinitis, shortness of breath, cough, chest tightness, nausea/vomiting, exacerbation of asthma, allergic skin reaction, and visual disorder. The prevalence of symptoms was consistently higher among workers in the printing process than among other workers. Smoking cigarettes and drinking alcohol were not associated with an increased prevalence of acute symptoms among these printing-factory workers. Conclusion. The significant associations were found between personal protective equipment and personal hygiene and prevalence of acute symptoms in printing workers.

Occupational risk factors for nasopharyngeal cancer among female textile workers in Shanghai, China

AIMS

To investigate whether occupational exposure to dusts and chemicals in the Chinese textile industry are associated with risk of nasopharyngeal cancer.

METHODS

Sixty seven nasopharyngeal carcinoma (NPC) cases identified during 1989-98 and a random sample (n = 3188) of women were included in a case cohort study nested in a cohort of 267,400 women textile workers in Shanghai, China. A complete occupational history of work in the textile industry was obtained for each woman. A job exposure matrix developed by experienced industrial hygienists was used to assess exposures to specific dusts and chemicals.

RESULTS

Risk of NPC is associated with cumulative exposure to cotton dust. The hazard ratio for women cumulatively exposed to >143.4 mg/m3 x years of cotton dust was 3.6 (95% CI 1.8 to 7.2) compared with unexposed women. Trends of increasing risk were also found with increasing duration of exposure to acids and caustics (p = 0.05), and with years worked in dyeing processes (p = 0.06). Women who worked at least 10 years in dyeing processes had a 3.6-fold excess risk of NPC (95% CI 1.0 to 12.1).

CONCLUSIONS

Occupational exposure to cotton dust, acids, and caustics, and work in dyeing and printing jobs in the textile industry may have increased risk of NPC in this cohort.

Increased morbidity from nasopharyngeal carcinoma and chronic pharyngitis or sinusitis among workers at a newspaper printing company

OBJECTIVES

To determine the association between printing works and nasopharygeal carcinoma as well as other diseases.

METHODS

Demographic data were obtained for those who had worked in a particular newspaper company since its establishment in 1950. Through access to the data bank of the hospital records of the Labor Insurance Bureau for 1985-94, all workers were identified who had been admitted to hospital during their employment in the newspaper company. Multiple logistic regressions were performed to estimate the adjusted morbidity odds ratio (OR) for various diseases among the printing workers with cardiovascular diseases as the reference diseases. Biopsy specimens from patients with nasopharyngeal carcinoma were all subjected to in situ hybridisation of Epstein-Barr virus (EBV), and colocalisation of EBV and secretor component protein.

RESULTS

Of the 1564 people who had worked in this company, 579 of them were admitted to hospital at least once. Five out of 144 printing workers admitted to hospital were diagnosed with nasopharyngeal carcinoma compared with none of the other 435 non-printing workers admitted to hospital. The morbidity OR for nasopharyngeal carcinoma in printing workers was 57.0 (95% confidence interval (95% CI) 2.8 to 1155.3). The morbidity OR for benign skin tumours was 28.0 (95% CI 2.7 to 293.1). Chronic pharyngitis or sinusitis also showed significant relations with printing works with a morbidity OR 29.4 (95% CI 1.7 to 514.7). Using all other diseases as the reference diseases for calculation of morbidity ORs still showed a similar trend. In situ hybridisation of EBV encoded small nuclear RNA-1 (EBER-1) showed tumour cells free of the EBV in each biopsy specimen. Colocalisation of EBER-1 and secretor component showed that some tumour cells contained both secretor component and EBV signal in each case.

CONCLUSION

Printing works are associated with an increased risk of nasopharyngeal carcinoma, benign skin tumours, chronic pharyngitis or sinusitis, chronic liver diseases, and mechanical injuries. Induction of the development of nasopharyngeal carcinoma is probably not related to EBV infection in these patients.

Incidence of cancer among bookbinders, printers, photoengravers, and typesetters

OBJECTIVES

To to study the risk of cancer, particularly of lung cancer and bladder cancer, among workers in the printing industry according to different occupations.

METHODS

This is a population based retrospective cohort study. The cohort comprised 1332 men and 426 women employed in the printing industry in Iceland according to a published union registry. A computerised file of the cohort was record linked to the Cancer Registry by making use of personal identification numbers. Expected numbers of cases of cancer were calculated on the basis of number of person-years and specific incidences of cancer sites for men and women provided by the Cancer Registry.

RESULTS

Among the men (36 217.5 person-years at risk) there were 125 observed cancers versus 123.66 expected, standardised incidence ratio (SIR) 1.01, 95% confidence interval (95% CI) was 0.84 to 1.20. The SIR (95% CI) for liver cancer was 1.97 (0.55 to 5.20) and the SIR for non-Hodgkin's lymphoma was 2.26 (0.96 to 4.41). No excess risk for cancer was found among women (8631.0 person-years at risk). The SIR (95% CI) for liver cancer was 4.21 (0.47 to 15.20) and for non-Hodgkin's lymphoma it was 4.99 (1.61 to 11.63) among the typesetters. A survey on smoking habits among active and retired union members showed that they smoked less than a random sample of the general population.

CONCLUSION

The cancer site most often reported to show excess risk among printing industry workers has been the lung and the urinary bladder; however, this was not found in the present study. This may be explained by difference in smoking habits among union members compared with the general population. There is a high occurrence of non-Hodgkin's lymphoma, particularly among typesetters, which warrants further studies.

Mortality in a cohort of toluene exposed employees (rotogravure printing plant workers)

Since the beginning of the 1960s, toluene has been used as a solvent in all German rotogravure printing plants in a high degree of purity. These particular exposure conditions allow the investigation of the potential carcinogenicity of long-term toluene exposure. A historical cohort study was performed that included 6830 German men from 11 plants who were exposed to toluene from 1960 to 1992 in three work areas with different exposure levels. Overall, 466 deaths were observed, which provided a standardized mortality ratio (SMR) of 91.3 for overall mortality. A significantly decreased SMR for total mortality was seen in one of the three work areas (SMR = 67). Mortality from cancer did not differ substantially from the expected level, but in one of the work areas, mortality from cancers of the bone (Ninth Revision of the International Classification of Disease [ICD]-9 170; SMR = 813) and connective tissue (ICD-9 171; SMR = 631) was significantly elevated. In the entire cohort, mortality from lung cancer was increased by about 35% above total mortality, and by about 95% in one work area with low toluene exposure (not statistically confirmed). The SMR for death from alcohol dependence was statistically significantly increased (ICD-9 303; SMR = 314).

The prevalence of pulmonary and upper respiratory tract symptoms and spirometric test findings among newspaper pressroom workers exposed to solvents

To investigate the relationship between exposure to organic solvents and the presence of pulmonary and upper respiratory tract mucous membrane symptoms, we conducted a cross-sectional study of 215 newspaper pressroom workers who were occupationally exposed to organic solvent and lubricant mixtures. Thirty-four compositors, who were not occupationally exposed to the solvents or lubricants, served as controls. Pressroom workers and compositors underwent spirometric testing and were also asked about the presence of cough, phlegm, hemoptysis, dyspnea, wheezing, chest tightness, nose or throat irritation, eye irritation, and sinus trouble. The spirometric results did not significantly differ between the two groups. However, the pressroom workers were significantly more likely to report pulmonary or upper respiratory tract mucous membrane symptoms than were compositors (P < 0.005). An exposure-response relationship could be demonstrated when comparing the number of solvents exposed with the total number of symptoms (P < 0.001). Similarly, an exposure-response relationship could be demonstrated when comparing the frequency of use of each of the seven solvents with the total number of symptoms (P < 0.002). Each of these findings was supported in a multivariable linear regression model that adjusted for potential confounders such as age, smoking history, and number of years in the industry. A high prevalence of these symptoms was reported even though the degree of exposure to solvents and lubricants was within the current permissible exposure limits.

Cancer mortality among magazine printing workers

OBJECTIVE

After an inquiry from the employees of an offset printing plant, a historical cohort study was conducted to investigate cancer mortality among these workers.

METHODS

The cohort comprised 262 men, who contributed 2771 person-years of observation. 16 deaths were identified during the follow up period (1980-91). Expected numbers of deaths were derived from age specific regional rates. Standardised mortality ratios (SMR) and 95% confidence intervals (95% CIs) were calculated.

RESULTS

An increased cancer mortality was found after 10 years of employment (SMR 213, 95% CI 98 to 405, based on nine deaths), mainly due to a high mortality from lung cancer (SMR 381, 95% CI 104 to 975, four deaths), and from oesophageal cancer (SMR 1049, 95% CI 216 to 3065, three deaths). For workers with at least 20 years since the start of employment, the SMR was 262 (95% CI 105 to 540) for all cancer sites, 447 (95% CI 92 to 1306) for lung cancer, and 1094 (95% CI 132 to 3952) for oesophageal cancer. The increased cancer mortality was concentrated among pressmen.

CONCLUSION

Although based on small numbers, the findings suggest an increased risk of cancer among these workers, which should be further investigated.

Clinical features of hematopoietic malignancies and related disorders among benzene-exposed workers in China. Benzene Study Group

Previous occupational cohort studies of benzene-exposed workers have for the most part used only death certificates to validate diagnoses of workers developing leukemia and other hematopoietic and lymphoproliferative malignancies and related disorders (HLD). In a follow-up study of 74,828 benzene-exposed workers and a comparison group of 35,805 nonexposed workers from 12 cities in China, we sought to characterized clinicopathologically and to confirm diagnoses of all cases of HLD. Using medical records, laboratory hematology results, and histopathology, U.S. and Chinese expert hematopathologists, blinded to exposure status, carried out a detailed review using standardized evaluation forms. Key among the findings were a notable diversity of malignant and nonneoplastic hematopoietic and lymphoproliferative disorders, documentation of excess myelodysplastic syndromes among benzene workers, and widespread dyspoiesis involving all hematopoietic cell lines. As sophisticated clinicopathologic characterization and corresponding classification schemes for HLD become increasingly widespread, it is recommended that future epidemiologic investigations of benzene workers incorporate similarly detailed morphologic evaluation. In extending follow-up of this cohort of young workers, we will continue to use all available clinical, laboratory hematology, and pathology data as well as cytogenetic and biochemical markers to characterized various HLD outcomes. These careful surveillance mechanisms should also provide additional insight into carcinogenic mechanisms of benzene and allow comparison of the molecular pathogenesis of HLD induced by benzene versus chemotherapy, radiation, or other exposure.

Cancer in printing workers in Denmark

OBJECTIVES

To study the cancer incidence in printing workers in Denmark.

METHODS

The cohort of 15,534 men and 3593 women working in the printing industry in 1970 were followed up for death, emigrations, and incident cancer cases until the end of 1987. Their cancer incidence was compared with that of all economically active people in Denmark. The smoking and drinking habits reported by members of the printing trade unions at a survey in 1972 were compared with habits reported by members of other trade unions.

RESULTS

Lung, bladder, renal pelvis, and primary liver cancers were in excess among the printing workers. The excess risks of lung cancer among the factory workers in newspaper and magazine production, of bladder cancer in typographers in printing establishments, of renal pelvis cancer in typographers and lithographers, and of primary liver cancer among lithographers and bookbinders exceeded those expected based on the reported smoking and drinking habits.

CONCLUSION

Our results indicate, in line with a previous study from Manchester, that work with rotary letterpress printing was associated with an increased risk of lung cancer. The inconsistent results from studies on bladder cancer in printing workers may point to a risk confined to a certain subgroup. The sixfold risk of primary liver cancer in Danish lithographers warrants studies in other countries.

Lung cancer among newspaper printers exposed to ink mist: a study of trade union members in Manchester, England

A nested case-control study of lung cancer among men exposed to ink mist in newspaper production with rotary letterpress technology is presented. It is based within a historical cohort of 9232 printing workers in Manchester (1949-63). Men who operated newspaper rotary letterpress machines had a lung cancer standardised mortality ratio (SMR) of 179 (95% confidence interval (95% CI) 144-218) when compared with rates for England and Wales for the follow up period 1950-83. When adjustment was made for the higher rates in the local area, the SMR was reduced to 122 (95% CI 98-148). The nested case control study was based on 110 lung cancer cases (1949-86) and 316 matched controls. Duration of work in a rotary letterpress machine room was positively associated with risk of lung cancer (chi 2 linear trend = 3.30, p = 0.07); mean with 30 or more years duration of exposure had a risk of 1.73 (95% CI 0.94-3.17), relative to those with less than 20 years of exposure. Adjustment for period of first exposure in a machine room reduced the strength of the positive duration effect. The magnitude of the SMRs found in the cohort study could be explained by confounding with smoking. The duration effect seen in the case-control study, however, suggests that there may be a real effect of exposure to letterpress ink mists. This is biologically plausible, as benzo[a]pyrene, a known human carcinogen, has been found in appreciable concentrations in the atmosphere of rotary letterpress machine rooms.