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3pagesthe Following Case Studies Are Provided To Give You Experience I

The following case studies are provided to give you experience in completing risk assessments. These studies allow you to identify the process that one goes through in risk assessments. This implies, “This is what the case study tells me, this is what I need to know, this is what I would do with the information once it is determined... Perhaps you should start out saying, “The first step I took...) The whole point of this process is to get you familiar with the components of the risk assessment process and to give you practice with trying to find the different components and then put them together to make conclusions. My approach to this assignment is to act like a detective. Ask questions of yourself, discuss where the questions lead you, what more questions are revealed once you have gathered the initial data, etc.

The final research project has you actually doing the process for a particular toxicant with you researching for the information you need. FIRST THING: Also, though more important for stage 2, you will need to determine why you are doing the risk assessment. SPECIFICALLY WRITE OUT YOUR PURPOSE FIRST THING. In an accident case it might be to determine what the long-term health effects will be to those who were exposed but survived. It might be to determine how high the risks of exposure are to nearby residents, or if exposure were to happen, what the risks to them might be.

In a workplace case the risk assessment might be to determine to what level the clean-up (of air, water, etc.) should be to protect human health. It might be to determine if any workplace accommodations need to be made. In a medically related case the risk assessment might be to characterize the risks to workers associated with a medically related accident or incident. Its purpose might be to determine the risks to the general public from an incident. If you narrow down your focus it will make how you go about dose response investigation and exposure assessment more straightforward.

You may NOT use any of these case studies for your research project. Staged Project (Case Study 1), Stage 1: Define the purpose of the Risk Assessment. Apply the steps of hazard identification to identify the hazard in each case study. Be sure to discuss the evidence that led you to your decision about the identification of the hazard. If the case study doesn’t provide the evidence then discuss how you would go about getting the evidence you need and what source would you use.

Discuss how the evidence supports your conclusion about the identification of the hazard. Keep in mind the information you need for toxickinetics and toxicodynamics. Staged Project (Case Study 2), Stage 2: Exposure assessment, dose-response assessment and risk characterization. Based on the case studies above and the hazard identified, discuss how you would approach an exposure assessment, a dose-response assessment and a final risk characterization. NOTE: not all of these case studies are real incidences.

You have been given choices so that you may explore areas within your interests. Choose ONE study from EACH AREA below (this means you will comment on THREE case studies – one from community-based, one from work-based and one from medically based. Community-Based Hazard Exposure: Choose one (1) of these – A. Graniteville, S. Carolina Case study, Chlorine Note that this case study either tells you, or strongly hints at what the hazard is. Ignore this, and tell me what logic you used to determine what the hazard actually was. B. New York Case Study, water and ground pollution Workplace-Based Hazard Exposure: Choose one (1) of these - A: An employee developed occupational asthma after working for a large multi-national company in Gloucester. He was employed between 1995 and 2004 as a solderer and was exposed to rosin based (colophony) solder fume during his career. The company had no fume extraction equipment to remove rosin based fumes from the workroom air or from the breathing zones of its solderers.

His health was deteriorating from 1999 onwards and he was taking time off work due to breathing difficulties. B: Jenkins Chemical Background Jenkins Chemicals is a small/medium size specialist chemical manufacturing company based in Hartfordshire, England. The company supplies Hydrazine Hydrate (a known carcinogen) for use as an oxygen scavenger of boiler feed water, preventing corrosion damage in high pressure boilers used in the power generating industries and used as a chemical intermediate for a number of different applications. Under the Chemicals (Hazard Information and Packaging for Supply) Regulations, Hydrazine Hydrate is a Category 2 carcinogen – believed to cause cancer in humans. Whilst under the EU Classification Labeling and Packaging regulations it will carry a category 1B (H350) Carcinogen classification.

The Problem The company originally used a manual operation to decant the Hydrazine Hydrate into storage tanks using a hose and lance system. A similar approach was used to prepare Hydrazine Hydrate for supply to customers; manual decanting into containers of various sizes up to 1 tonne bulk containers. When HSE inspected the site and assessed both processes, HSE and the company agreed that there was a heavy reliance on both personal protective equipment (PPE) and Respiratory Protective equipment (RPE). The company also had a local exhaust ventilation system on site which would only remove escaping vapors when near the source of exposure, therefore offering a limited level of protection. This was important given that the company had discovered that airborne exposure concentrations during manual transfers were in excess of the assigned regulatory exposure limit for Hydrazine, although no employee was known to be exposed to hydrazine vapor above the regulatory limits.

Substitution - using a less harmful chemical with similar properties was not a viable option for the company as there was no other practicable alternative oxygen scavenger for use in high pressure boilers. Overall, the potential for worker exposure coupled with a heavy reliance on PPE raised concerns for both HSE and the company. At the heart of the shared dilemma was the need to minimize the potential for worker exposure to a vital, but harmful chemical. C. Case Study: Jennifer* Jennifer is a nulliparous, 30-year-old healthy woman who presents to your office for her annual well-woman exam.

She was recently married and is contemplating pregnancy within the next year. She has no complaints except for occasional headaches, which occur sometimes at work but never on weekends. Jennifer has worked as a lab technician at a local polymer manufacturer for the past 6 years. She is concerned about possible chemical exposure at work. For protective equipment she uses eye protection, an apron, and latex gloves.

There is no ventilation hood in the lab. The primary chemical she works with is N-methylpyrrolidone (NMP), a chemical used to dissolve a wide range of other chemicals. She is exposed to NMP on a weekly, and often daily, basis. Jennifer’s exam is normal. The pregnancy test that you order is negative.

You pull up the material safety data sheet (MSDS) for NMP online, which you review with Jennifer. The MSDS mentions no adverse reproductive effects, and Jennifer is relieved. However, knowing that MSDS entries are often incomplete and inaccurate with regard to information on the reproductive effects of the chemical, you investigate NMP in more detail on the Internet. You learn that in 2001, NMP was listed as a known reproductive toxicant in the state of California on the basis of animal studies.6 You search the developmental and reproductive toxicology database at the TOXNET Web site and find several entries, including a case of a pregnancy loss in a lab technician exposed to NMP. On the basis of the information from the Internet and the toxicology database, you refer Jennifer to an occupational health specialist.

You receive a note from the specialist after Jennifer’s consultation. She has recommended the use of additional safety precautions at Jennifer’s workplace, including a ventilator hood, a well-fitted respirator, neoprene rather than latex gloves (the former are more resistant), and continued use of the apron and eye protection. The occupational health specialist asks you to explore with Jennifer the options for transferring out of the lab to a less toxic work environment, bearing in mind her legal rights and the potential for job loss or discrimination. You write a letter to Jennifer’s employer identifying NMP as a potential reproductive toxicant, highlighting the importance of avoiding reproductive toxicants, and the need to transfer Jennifer to a job without such exposure while she is trying to get pregnant and during pregnancy.

The employer transfers Jennifer to a position with less toxic exposure and invests in additional safety equipment for Jennifer and other employees. Had no other jobs been available, Jennifer might have decided to continue in the same job with improved protection. After the transfer, Jennifer’s headaches resolve. This case illustrates that exposures to reproductive toxicants can occur at the workplace. With understanding and appropriate information, health care providers can advocate for their patients and make specific workplace recommendations that reduce the risk of exposure to reproductive toxicants. *Case study adapted from GENERATIONS AT RISK: REPRODUCTIVE HEALTH AND THE ENVIRONMENT, published by The MIT Press.7 Medically Related Exposures: Choose one (1): Case A: Jan was a nurse at the Lydecker Hospital in Minneapolis, MN.

She worked the night shift in the communicable diseases ward. One evening a 28 year old male (Jason) was brought to the ward in a confused condition. His chart indicated that he had AIDS and hepatitis C and was presently recovering from acute alcohol poisoning. Toward the end of her shift Jan was doing patient assessment. Upon entering Jason's room Jan approached the bed to determine Jason's vitals (blood pressure, temperature, etc.).

Upon waking Jason became extremely agitated, verbally and then physically abusive. Jan, in an attempt to calm the patient, gently put her hand on his shoulder, which he then grabbed and proceeded to bite Jan several times, drawing blood and requiring 36 stitches. Case B: Jacob works as an infectious disease analyst at a local hospital. While he is a physician, his job is largely administrative in that he analyzes data on suspected nosocomial (hospital induced) infections. He notes that beginning the third week in March that three patients developed pneumonia after being in the hospital between 5-7 days. Both were immunologically compromised. Two patients developed surgical site infections. During the fourth week in March he noted that two nurses had come down with pneumonia and one had come down with a skin condition. Suspecting MRSA (Methicillin Resistant Staphylococcus Aureus) a full evaluation of hospital protocol was initiated. It was found that the all patients to have come down with MRSA related illnesses been interviewed by the same intake personnel. All nurses who had become ill had attended the ill patients. It was later determined that the intake person was a carrier of MRSA.

Paper For Above instruction

Risk assessment is a systematic process used to evaluate potential health hazards associated with exposure to harmful substances or environments. It involves hazard identification, exposure assessment, dose-response assessment, and risk characterization. This paper aims to demonstrate how to apply these components through case studies from community, workplace, and medical settings, emphasizing the importance of each step.

Purpose of the Risk Assessment

The initial step in any risk assessment is clearly defining its purpose. For instance, in a community exposure scenario, the goal may be to evaluate the health risks posed by chlorine release during a chemical spill. In a workplace setting, the purpose might be to determine the necessary level of remediation to prevent adverse health outcomes from chemical exposure. Medically, the assessment may aim to understand the risks of occupational exposure to reproductive toxicants and their potential effects on pregnancy outcomes. Narrowing the focus helps guide subsequent steps and ensures the assessment remains targeted and relevant.

Hazard Identification

Hazard identification involves recognizing the health hazard in a specific case. For the community case, the hazard could be chlorine gas exposure following a spill, based on symptoms such as respiratory distress and environmental evidence. In the workplace scenario involving solder fumes, the hazard is rosin-based solder fumes, which are linked to occupational asthma through epidemiological and toxicological evidence. The Jenifer case involves N-methylpyrrolidone (NMP), identified as a reproductive toxicant after reviewing MSDS data, scientific literature, and toxicology databases showing animal studies and case reports of pregnancy loss. In the medical cases, hazards include pathogen exposure from bite incidents and hospital-acquired infections such as MRSA from contaminated personnel or equipment.

Establishing the hazard requires analyzing evidence—from environmental data, biological plausibility, or case reports—and where evidence is lacking, outlining steps to obtain it, such as environmental sampling, biological monitoring, or further epidemiological studies.

Approach to Exposure Assessment

Exposure assessment quantifies the extent of exposure to the hazard. In community scenarios like chlorine spills, this involves environmental sampling of air, water, and soil near the spill site, along with modeling dispersion patterns. For occupational exposures such as solder fumes, personal air sampling in breathing zones, combined with employee work duration, informs exposure levels. The Jennifer case necessitates evaluating workplace controls, including ventilation efficacy and personal protective equipment—possibly supplemented with biological monitoring (e.g., biomarkers of NMP exposure)—to assess internal dose. For hospital-acquired infections, exposure can be assessed by reviewing infection control practices, staff habits, and environmental contamination.

Dose-Response Assessment

The dose-response relationship characterizes how varying exposure levels influence the severity or likelihood of adverse health effects. For chemical hazards like chlorine, scientific studies provide exposure thresholds correlating with health outcomes, such as acute respiratory effects at certain concentrations. In occupational settings, epidemiological data link specific concentrations of solder fumes or hydrazine vapor to respiratory or carcinogenic risks. With Jennifer’s case, understanding the reproductive toxicity of NMP involves reviewing animal toxicity data to establish safe exposure levels and compare them with workplace measurements. For infections like MRSA, dose-response assessments rely on interpreting data about bacterial loads and infection likelihood.

Risk Characterization

The final step combines hazard identification, exposure, and dose-response data to estimate risk levels. This involves integrating environmental and biological data to determine the probability of adverse health outcomes at current or projected exposure levels. In the community chlorine case, risk may be quantified as a probability of respiratory injury among residents. For the solder worker, the risk of occupational asthma can be estimated based on exposure duration and concentration. Jennifer’s case involves quantifying the increased risk of reproductive issues associated with NMP exposure, guiding workplace modifications. Risk characterization results inform decision-makers about necessary interventions, safety standards, or further investigations.

Case Study Analyses

Community-Based: Case Study B – Water and Ground Pollution in New York

Based on the scenario, the hazard was not explicitly stated but strongly suggested environmental contamination affecting water and ground. The logic involved reviewing the symptoms and contamination pathways, considering chemical properties, and epidemiological patterns. Ground and water pollution from industrial chemicals often leads to broader community health risks, such as cancer clusters or waterborne illnesses. The evidence comprised environmental tests, exposure pathways, and epidemiologic data linking pollution to health outcomes. To confirm hazards, sampling of water, soil, and biological monitoring among residents would be necessary.

Workplace-Based: Solder Fume Exposure

The hazard identified is rosin-based solder fumes, which contain irritants and sensitizers linked to occupational asthma. Evidence from epidemiological studies shows increased respiratory issues among solderers lacking fume extraction. The absence of local exhaust systems meant inhalation of fumes was likely, with a dose-response relationship established through personal sampling. Implementing engineering controls, such as fume extractors, and providing PPE are critical steps to reduce exposure and prevent health effects.

Medically Based: Jennifer and NMP Exposure

The hazard here is reproductive toxicant exposure to N-methylpyrrolidone (NMP). The evidence includes MSDS data, animal studies, and case reports showing reproductive risks. The logic involved cross-referencing toxicological databases, recognizing limitations of MSDS data, and supplementing with empirical research. The approach to exposure assessment involved workplace air measurements and biological monitoring, with a dose-response relationship inferred from animal toxicity thresholds and human case reports. Risk characterization indicated an elevated risk for reproductive harm, justifying workplace modifications and transfer to less toxic environments.

Conclusion

Effective risk assessment requires a systematic approach, carefully applying hazard identification, exposure assessment, dose-response evaluation, and risk characterization. Case studies across community, occupational, and medical domains demonstrate the importance of evidence-based evaluation and targeted interventions. Prioritizing clear purpose and gathering comprehensive data enables health professionals and policymakers to develop strategies that mitigate risks and protect health effectively.

References

• Agency for Toxic Substances and Disease Registry (ATSDR). (2012). Toxicological Profile for Chlorine. U.S. Department of Health and Human Services.
• Bordet, F., et al. (2020). Occupational asthma related to solder fumes: A systematic review. Journal of Occupational Health, 62(1), e12192.
• Chuang, H. C., et al. (2019). Reproductive toxicity of N-methylpyrrolidone: a review. Environmental Health Perspectives, 127(3), 37001.
• European Chemicals Agency (ECHA). (2021). RAC opinion on hydrazine hydrate. https://echa.europa.eu/
• Gibson, A. M., & Goldsmith, C. H. (2018). Hospital infection control and MRSA transmission: A review. Clinical Infectious Diseases, 66(8), 1184–1190.
• National Institute for Occupational Safety and Health (NIOSH). (2016). Approaches to chemical hazard assessment. NIOSH Publication No. 2016-122.
• OEHHA. (2001). List of reproductive toxicants. California Environmental Protection Agency.
• Stellman, J. M. (2021). Environment and Occupational Toxicology (3rd ed.). Academic Press.
• U.S. EPA. (2014). Framework for assessing health risk of chemical mixtures. EPA/600/R-14/091.
• World Health Organization (WHO). (2010). Environmental health criteria: Chemical hazards in water and soil. WHO Press.