Research A Carcinogen That Can Be Classified As Either An En ✓ Solved
Research A Carcinogen That Can Be Classified As Either An Environmenta
Research a carcinogen that can be classified as either an environmental or occupational toxicant that has had relevance in the news within the last five years. In your paper, analyze and briefly summarize the situation that brought the carcinogen to newsworthy status. Discuss the exposure limits of this carcinogen, and how individuals were exposed. Also, discuss the toxicological effects that were not only observed, but all of the possible effects of this agent. In referencing Chapter 23 from your assigned reading, briefly discuss the models used for assessing cancer risks.
Your analysis should be at least three pages in length. The title page and reference page are not included in the required paper length. Your paper must contain at least three references and may include reliable internet sources, books, and professional journals or resources related to the profession. All sources used, including the textbook, must be referenced; paraphrased and quoted material must have accompanying citations.
Sample Paper For Above instruction
Introduction
In recent years, concerns surrounding environmental carcinogens have garnered significant attention from both the scientific community and the public. One such carcinogen that has been prominently featured in the news within the last five years is asbestos. Recognized historically for its use in construction and industrial applications, asbestos exposure has been linked to a variety of cancers, notably mesothelioma and lung cancer. This paper examines asbestos as an environmental and occupational carcinogen, explores the circumstances that brought it into the spotlight recently, discusses exposure limits, toxicological effects, and evaluates the risk assessment models used to understand its carcinogenic potential.
Background and Newsworthiness
Asbestos remains a concern due to ongoing legacy contamination and renewed awareness of its health impacts. In 2020, news reports highlighted the danger of asbestos exposure in homes undergoing renovation, especially in older buildings where asbestos-containing materials (ACMs) were present but not properly remediated. Several lawsuits and investigations uncovered that improperly managed asbestos led to heightened exposure risks for workers and residents. The media coverage prompted increased regulatory scrutiny, emphasizing the need for strict controls and public awareness campaigns. The resurgence of concern was also fueled by new scientific studies indicating that even minimal exposure could contribute to carcinogenesis, challenging previous safety standards.
Exposure Limits and Modes of Exposure
Occupational exposure limits for asbestos have been established by several agencies, including the Occupational Safety and Health Administration (OSHA) and the Environmental Protection Agency (EPA). OSHA's permissible exposure limit (PEL) for asbestos is 0.1 fiber per cubic centimeter of air (f/cc) averaged over an 8-hour workday, whereas the EPA's guidelines recommend minimizing exposure as much as possible due to its carcinogenic nature. Individuals are primarily exposed through inhalation of airborne fibers, which may occur during activities such as demolition, construction, manufacturing, or home renovations involving older building materials. Secondary exposure can occur through contaminated clothing or dust settling in living or working environments.
Toxicological Effects
Asbestos fibers cause pathogenic effects primarily through chronic inflammation, cellular damage, and genotoxicity induced by the fibers' physical and chemical properties. When inhaled, asbestos fibers can lodge within the lung tissue and pleural linings, leading to asbestosis—a fibrotic lung disease characterized by scarring and impaired respiration. Long-term exposure increases the risk of developing malignancies such as mesothelioma, a cancer of the mesothelial cells lining the lungs and abdomen, and lung carcinomas. Recent studies also suggest potential links to other cancers, including laryngeal and ovarian cancers. The carcinogenic process involves fiber persistence, oxidative stress, and DNA damage, promoting mutations and cellular transformation.
Cancer Risk Assessment Models (Chapter 23 Reference)
Chapter 23 of the assigned textbook discusses various models for assessing cancer risks associated with chemical exposures. Quantitative cancer risk assessment often employs dose-response models like the linear no-threshold (LNT) model, which assumes that any non-zero dose of a carcinogen increases cancer risk proportionally. This conservative approach is widely used for asbestos, especially when epidemiological data are limited or uncertain. Benchmark dose modeling and molecular epidemiology are also employed to refine risk estimates, considering individual susceptibility and fiber dose. These models help regulatory agencies establish exposure limits and develop protective policies. In the case of asbestos, risk assessments underpin regulatory actions aimed at minimizing exposure and preventing asbestos-related diseases.
Conclusion
Asbestos exemplifies a carcinogen that poses significant environmental and occupational health challenges. Recent news coverage has heightened awareness of its persistence in older buildings and the risks associated with improper management. Understanding its exposure pathways, toxicological effects, and risk assessment models are vital for developing effective control measures. Continued research and stringent regulatory standards are essential to prevent asbestos-related diseases and protect public health.
References
1. Agency for Toxic Substances and Disease Registry (ATSDR). (2019). Toxicological Profile for Asbestos. U.S. Department of Health and Human Services.
2. International Agency for Research on Cancer (IARC). (2012). IARC Monographs on the Evaluation of Carcinogenic Risks to Humans: Asbestos (Review of Human Carcinogens).
3. Occupational Safety and Health Administration (OSHA). (2016). OSHA Fact Sheet: How to Manage Asbestos in the Workplace. OSHA.
4. World Health Organization (WHO). (2014). Asbestos Fact Sheet. WHO.
5. Lee, T., & Landrigan, P. J. (2019). "Assessing Cancer Risk from Asbestos." Environmental Health Perspectives, 127(4), 44002.
6. Donaldson, K., et al. (2017). "The Toxicology of Asbestos." Toxicology Letters, 268, 21-27.
7. Kamp, D. W. (2015). "Asbestos and Lung Disease." Clinics in Chest Medicine, 36(4), 793–800.
8. Teta, M. J., et al. (2021). "Fibers and Carcinogenesis: Mechanisms and Risk Assessment." Journal of Occupational and Environmental Medicine, 63(2), 107-116.
9. Ruggieri, M., et al. (2020). "Environmental Exposure to Asbestos: Recent Developments." Environmental Science & Technology, 54(4), 2015–2023.
10. World Health Organization. (2014). Elimination of asbestos-related diseases: comprehensive action plan. WHO.