Tuesday, July 31, 2018

There Is A Cancer Epidemic Related To Asbestos Exposure

"Asbestos exposure is responsible for the death of millions of people worldwide and the debate on how to handle this crisis is still ongoing. There are a myriad of political and economic obstacles surrounding the issue, and some are uncomfortable subjects to discuss.

One interesting article to start your research is called, ?The asbestos cancer epidemic.? By Joseph LaDou - Division of Occupational and Environmental Medicine, University of California-San Francisco School of Medicine, - Environ Health Perspect. 2004 March; 112(3): 285?. Here is an excerpt: ?The asbestos cancer epidemic may take as many as 10 million lives before asbestos is banned worldwide and exposures are brought to an end. In many developed countries, in the most affected age groups, mesothelioma may account for 1% of all deaths. In addition to mesotheliomas, 5-7% of all lung cancers can be attributed to occupational exposures to asbestos. The asbestos cancer epidemic would have been largely preventable if the World Health Organization (WHO) and the International Labor Organization (ILO) had responded early and responsibly. 
The WHO was late in recognizing the epidemic and failed to act decisively after it was well under way. The WHO and the ILO continue to fail to address the problem of asbestos mining, manufacturing, and use and world trade of a known human carcinogen. Part of the problem is that the WHO and the ILO have allowed organizations such as the International Commission on Occupational Health (ICOH) and other asbestos industry advocates to manipulate them and to distort scientific evidence. The global asbestos cancer epidemic is a story of monumental failure to protect the public health.?

A second study worth examining is called, ?Cancer in asbestos-exposed occupational cohorts: a meta-analysis? Cancer Causes and Control - Volume 10, Number 5 / August, 1999 ? by Michael Goodman, Robert W. Morgan, Rose Ray, Curtis D. Malloy and Ke Zhao. Here is an excerpt: ?Abstract Objective: To examine existing asbestos-exposed occupational cohorts and apply a meta-analytic technique to determine the magnitude of association between exposure and lung cancer and to investigate other cancer sites that may be related to such an exposure. Methods: We summarized the data from 69 asbestos-exposed occupational cohorts reporting on cancer morbidity and mortality. Data were extracted regarding numbers of deaths for each cancer, numbers of mesotheliomas, occupations and latency for respiratory, gastrointestinal, urinary and lymphohematopoietic cancers. For each cancer, we calculated a meta-SMR and examined heterogeneity of results using a chi-square test and by calculating a Z-statistic for each study. To examine the dose?response effect, we divided the studies into tertiles according to the percentage of mesothelioma deaths that served as a proxy estimation of asbestos exposure.

Results: Lung cancer data demonstrated meta-SMRs of 163 and 148 with and without latency, respectively, with significant heterogeneity of results even after stratification according to occupational groups. Stratification of lung cancer studies according to percentage of mesothelioma deaths showed a dose?response effect. Z-scores ranged from ? 12.21 to + 29.49. Analysis for laryngeal cancer yielded meta-SMRs of 157 and 133 with and without latency, respectively, demonstrating homogeneous results across studies but accompanied by no evidence of a dose?response effect. Data for gastrointestinal cancers showed no evidence of a significant association and no dose?response effect. Kidney cancer demonstrated statistically non-significant meta-SMRs of 120 (95% CI 88?160) and 111 (95% CI 94?131) with and without latency respectively.
Conclusions: This meta-analysis demonstrates a wide variability of the association between occupational asbestos and lung cancer. There was a suggestion of an association between asbestos and laryngeal carcinoma and no clear association with other cancers.?

A third study is called, ?Asbestos and renal adenocarcinoma: A case-control study? by Malcolm Maclure - Environmental Research Volume 42, Issue 2, April 1987, Pages 353. Here is an excerpt: ?A case-control study of renal adenocarcinoma has corroborated the hypothesis that asbestos is a cause of the disease. The odds of having been moderately or heavily exposed to asbestos 30 years before diagnosis were 45:473 among cases, whereas the comparable odds among controls were 26:492. A matched-pair analysis yielded an exposure odds ratio of 1.8 with 95% confidence limits of 1.1 and 3.1. After controlling for potential confounders and selection factors by means of logistic regression, the incidence rate ratio was estimated to be 1.6, with a one-sided 95% confidence limit of 1.0.?
If you found any of these excerpts interesting, please read the studies in their entirety. We all owe a great deal of gratitude to these researchers."