Cancer mortality among jewelry workers

Human exposure to heavy metals and related cancer development: a bibliometric analysis

As notifications on carcinogenicity of heavy metals increase, more and more attention is paid recently to heavy metals exposure. In our study, the human exposure to heavy metals and cancer knowledge epistemology was investigated using bibliometric analysis. The bibliometric data of the research articles were retrieved using following keywords: "heavy metal," "trace element", "cancer", "carcinogen", and "tumor" in the Scopus database. Specifically, 2118 articles published between 1972 and 2023 were found, covering a total of 1473 authors, 252 sources, and 2797 keywords. Retrospective data obtained from 251 documents and 145 journals were further analyzed by performance analysis and techniques of science mapping. The number of studies conducted in this field increased from one article published in 1972 to 18 articles published in 2022 in the study of Michael P Waalkes. The most impactful author regarding the number of published papers was Masoudreza Sohrabi with 7 publications. In the majority of the published papers, the most popular keywords were "cadmium" and "carcinogenicity". However, in recent 4 years, the emphasis has been placed more on epidemiology studies. Our study provides general knowledge about the trend of publication on the role of heavy metals in causing cancer. The leading researchers in the field of the effects of heavy metals on the development of cancer were identified in our studies. Our results might also create a better understanding of new and emerging issues and can be used as a comprehensive road map for future researchers.

Investigating the risk of breast cancer among women exposed to chemicals: a nested case-control study using improved exposure estimates

Purpose

The aim of this study was to examine if exposures to chemicals at the workplace were associated with an increased risk of postmenopausal breast cancer, using improved exposure estimates.

Methods

The design is a case–control study, nested within a cohort of women from the Malmö Diet and Cancer Study. The study comprised 2400 women, 731 cases and 1669 matched controls, born 1923–1950 and living in Malmö, Sweden between 1991 and 1996. An occupational hygienist reclassified the probability for exposure given by a job-exposure matrix, using individual data on work tasks. First-time diagnoses of invasive breast cancer were identified through the Swedish Cancer Registry.

Results

Women exposed to chemicals in their occupational environment had a statistically significantly increased risk (OR 1.59, 95% CI 1.11–2.29) of breast cancer, and the risk correlated positively with duration of exposure but not with exposure intensity. Women exposed to chlorinated hydrocarbon solvents for more than 10 years had a significant higher risk of breast cancer (OR 3.06, 95% CI 1.18–7.96) as well as women exposed to oil mist for more than 10 years (OR 3.08, 95% CI 1.12–8.49).

Conclusions

This study gives some support to the hypothesis that exposure to organic solvents as well as oil mist is associated with increased risk of breast cancer.

Occupational silica exposure and risk of various diseases: an analysis using death certificates from 27 states of the United States

BACKGROUND

Although crystalline silica exposure is associated with silicosis, lung cancer, pulmonary tuberculosis, and chronic obstructive pulmonary disease (COPD), there is less support for an association with autoimmune disease, and renal disease.

METHODS

Using data from the US National Occupational Mortality Surveillance (NOMS) system, a matched case-control design was employed to examine each of several diseases (including silicosis, lung cancer, stomach cancer, oesophageal cancer, COPD, pulmonary tuberculosis, sarcoidosis, systemic lupus erythematosus, systemic sclerosis, rheumatoid arthritis, and various types of renal disease). Cases were subjects whose death certificate mentioned the disease of interest. A separate control group for each of the diseases of interest was selected from among subjects whose death certificate did not mention the disease of interest or any of several diseases reported to be associated with crystalline silica exposure. Subjects were assigned into a qualitative crystalline silica exposure category based on the industry/occupation pairing found on their death certificate. We also investigated whether silicotics had a higher risk of disease compared to those without silicosis.

RESULTS

Those postulated to have had detectable crystalline silica exposure had a significantly increased risk for silicosis, COPD, pulmonary tuberculosis, and rheumatoid arthritis. In addition, a significant trend of increasing risk with increasing silica exposure was observed for these same conditions and for lung cancer. Those postulated to have had the greatest crystalline silica exposure had a significantly increased risk for silicosis, lung cancer, COPD, and pulmonary tuberculosis only. Finally, those with silicosis had a significantly increased risk for COPD, pulmonary tuberculosis, and rheumatoid arthritis.

CONCLUSIONS

This study corroborates the association between crystalline silica exposure and silicosis, lung cancer, COPD, and pulmonary tuberculosis. In addition, support is provided for an association between crystalline silica exposure and rheumatoid arthritis.

Mortality from six work-related cancers among African Americans and Latinos

BACKGROUND

Ethnic minorities have been omitted from many occupational health studies, despite their substantial contributions to the labor force and documented cases of high exposures in some settings. To describe the occurrence of potentially work-related cancers among African American and Latino Workers, we conducted an epidemiologic study based on death certificate data.

METHODS

Data were obtained from 21 states during 1985-1992. Directly adjusted proportionate mortality ratios (PMRs) and standardized mortality rate ratios (SRRs) for ages 20-64 years were computed for cancers of the lung, nasal cavity, pleura, and peritoneum, malignant melanoma and leukemia using the mortality data and population counts from the 1990 census.

RESULTS

Proportionate mortality was generally low for both groups, but African Americans had higher than expected mortality rates for leukemia and cancers of the lung, nasal cavity, and peritoneum. Industry-specific analyses indicate excess leukemia among African American men in the rubber industry (PMR 2.08, 95% confidence interval (CI) 1.29 - 3.35), Latino men in textile (PMR 2. 31, 95% CI 0.81 - 5.13) and wood industries (PMR 2.03, 95% CI 0.81 - 5.13), and Latino women in the chemical industry (PMR 2.18, 95% CI 0.59 - 8.10), among other findings. Excess cancer of the pleura and peritoneum was observed among workers with a variety of usual occupations, consistent with widespread exposure to asbestos.

CONCLUSIONS

This study demonstrates the utility of surveillance data bases for generating basic epidemiologic information on historically neglected workers. Leads about specific workplace exposure can be followed up in more detailed studies.

Workplace exposures and oesophageal cancer

OBJECTIVES

To describe the relation between oesophageal cancer and many occupational circumstances with data from a population based case-control study.

METHODS

Cases were 99 histologically confirmed incident cases of cancer of the oesophagus, 63 of which were squamous cell carcinomas. Various control groups were available; for the present analysis a group was used that comprised 533 population controls and 533 patients with other types of cancer. Detailed job histories were elicited from all subjects and were translated by a team of chemists and hygienists for evidence of exposure to 294 occupational agents. Based on preliminary results and a review of literature, a set of 35 occupational agents and 19 occupations and industry titles were selected for this analysis. Logistic regression analyses were adjusted for age, birthplace, education, respondent (self or proxy), smoking, alcohol, and beta-carotene intake.

RESULTS

Sulphuric acid and carbon black showed the strongest evidence of an association with oesophageal cancer, particularly squamous cell carcinoma. Other substances showed excess risks, but the evidence was more equivocal-namely chrysotile asbestos, alumina, mineral spirits, toluene, synthetic adhesives, other paints and varnishes, iron compounds, and mild steel dust. There was considerable overlap in occupational exposure patterns and results for some of these substances may be mutually confounded. None of the occupations or industry titles showed a clear excess risk; the strongest hints were for warehouse workers, food services workers, and workers from the miscellaneous food industry.

CONCLUSIONS

The data provide some support for an association between oesophageal cancer and a handful of occupational exposures, particularly sulphuric acid and carbon black. Many of the associations found have never been examined before and warrant further investigation.

Lung function, biological monitoring, and biological effect monitoring of gemstone cutters exposed to beryls

OBJECTIVES

Gemstone cutters are potentially exposed to various carcinogenic and fibrogenic metals such as chromium, nickel, aluminium, and beryllium, as well as to lead. Increased beryllium concentrations had been reported in the air of workplaces of beryl cutters in Idar-Oberstein, Germany. The aim of the survey was to study the excretion of beryllium in cutters and grinders with occupational exposure to beryls--for example, aquamarines and emeralds--to examine the prevalence of beryllium sensitisation with the beryllium lymphocyte transformation test (BeLT), to examine the prevalence of lung disease induced by beryllium, to describe the internal load of the respective metals relative to work process, and to screen for genotoxic effects in this particular profession.

METHODS

In a cross sectional investigation, 57 out of 100 gemstone cutters working in 12 factories in Idar-Oberstein with occupational exposure to beryls underwent medical examinations, a chest radiograph, lung function testing (spirometry, airway resistance with the interrupter technique), and biological monitoring, including measurements of aluminium, chromium, and nickel in urine as well as lead in blood. Beryllium in urine was measured with a newly developed direct electrothermal atomic absorption spectroscopy technique with a measurement limit of 0.06 microgram/l. Also, cytogenetic tests (rates of micronuclei and sister chromatid exchange), and a BeLT were performed. Airborne concentrations of beryllium were measured in three factories. As no adequate local control group was available, the cutters were categorised into those with an exposure to beryls of > 4 hours/week (group A) and < or = 4 hours/week (group B).

RESULTS

Clinical, radiological, or spirometric abnormalities indicating pneumoconiosis were detected in none of the gemstone cutters. Metal concentrations in biological material were far below the respective biological limit values, and beryllium in urine was only measurable in subjects of group A. Cytogenetic investigations showed normal values which were independent of the duration of beryllium exposure. In one subject, the BeLT was positive. Beryllium stimulation indices were significantly higher in subjects with detectable beryllium in the urine than in those with beryllium concentrations below the detection limit (p < 0.05). In one factory, two out of four measurements of airborne beryllium concentrations were well above the German threshold limit value of 2 micrograms/m3 (twofold and 10-fold), and all gemstone cutters working in this factory had measurable beryllium concentrations in urine.

CONCLUSION

No adverse clinical health effects were found in this cross sectional investigation of gemstone cutters working with beryls. However, an improvement in workplace hygiene is recommended, accompanied by biological monitoring of beryllium in urine.

Occupational risk factors for female breast cancer: a review

OBJECTIVES

Although progress has been made in identifying personal risk factors and in improving treatment for female breast cancer, incidence rates continue to increase. With women now occupying a sizable fraction of the workforce, it is worth inquiring whether there are occupational risk factors for breast cancer. This is a review of occupational studies on female breast cancer.

METHODS

Suitable reports and published articles with associations of female breast cancer and occupation were identified from technical reports, by searching the MEDLINE bibliographic data base, and by reviewing each paper on cancer that was published in 20 major journals during the period from about 1971-94.

RESULTS

A total of 115 studies were identified; 19 studies relied exclusively on data collected for administrative purposes, and there were four incident case-control studies and 92 cohort studies. Although data for individual industries, occupations, and exposures were sparse, there was limited evidence of an association with employment in the pharmaceutical industry and among cosmetologists and beauticians. Associations were also found for chemists and occupations with possible exposure to extremely low frequency electromagnetic fields, but potential methodological weaknesses preclude drawing any definite conclusions. There was little support for increased risks among textiles workers, dry cleaning workers, and nuclear industry workers.

CONCLUSIONS

Few high quality occupational studies directed specifically toward women have been carried out to allow the unambiguous identification of occupational risk factors for breast cancer. It is suggested that investigations that account for non-occupational risk factors and that assess exposure in a more detailed way be carried out. One strategy already suggested is to conduct population based, case-control studies in which subjects are interviewed about their occupational histories and exposure to chemical and physical agents which are then attributed from the job descriptions by a team of experts. These studies can then be supplemented when necessary with cohort studies of specific populations.