This assignment is in two parts: Part 1: Exposure Assessment Case Study Read “Cross-sectional Exposure Assessment of Environmental Contaminants in Churchill County, Nevada” by the Centers for Disease Control and Prevention (2003). Use this case study to complete the Exposure Assessment form. Part 2: Risk Assessment Case Study Read “Illness Associated with Drift of Chloropicrin Soil Fumigant into a Residential Area – Kern County, California, 2003.” Use this case study to complete the Risk Assessment assignment. Please see the attachment

Exposure Assessment Case Study


Exposure assessment is a crucial step in environmental health studies as it involves estimating the levels of exposure to specific contaminants and evaluating potential risks to human health. The case study titled “Cross-sectional Exposure Assessment of Environmental Contaminants in Churchill County, Nevada” conducted by the Centers for Disease Control and Prevention (CDC) in 2003 provides valuable insights into the process of conducting exposure assessment in a specific population. This study aims to identify and understand potential exposure pathways and the associated health risks in Churchill County. This assignment will utilize the case study to complete the Exposure Assessment form.

Summary of the Case Study

The case study conducted by the CDC focuses on Churchill County, a rural community located in Nevada, which experienced an unusually high occurrence of childhood leukemia and other diseases. The study aimed to investigate potential environmental contaminants that could be responsible for these health issues. The researchers conducted an extensive exposure assessment to identify potential pathways of exposure and quantify the levels of exposure.


The exposure assessment utilized in this study involved multiple approaches, including questionnaire surveys, environmental sampling, and biomonitoring. Questionnaires were administered to residents to gather information on potential sources of exposure, such as occupation, hobbies, and lifestyle factors. Environmental samples, including air, water, soil, and food, were collected and analyzed for various contaminants. Biomonitoring involved measuring the concentrations of specific contaminants in the biological samples (e.g., blood, urine) of study participants.


The case study identified multiple potential exposure pathways in Churchill County, including contaminated soil, water, and air. The researchers found elevated levels of heavy metals, such as arsenic and lead, in the soil samples, which could be a result of past mining activities in the area. Additionally, high concentrations of pesticides were detected in air samples, indicating potential exposure through inhalation. The biomonitoring data revealed the presence of various contaminants in the blood and urine samples of study participants, further confirming exposure to these substances.


The exposure assessment conducted in Churchill County provided important insights into the potential sources of contamination and pathways of exposure. The findings highlighted the need for further investigations to establish the link between these exposures and the reported health issues. The study also emphasized the importance of community involvement and collaboration between researchers, public health agencies, and the residents to effectively address and mitigate exposure risks.


One limitation of this exposure assessment case study is the lack of specific exposure quantification for individual study participants. Although biomonitoring provided information on the presence of contaminants in biological samples, it did not provide a comprehensive understanding of the magnitude and duration of exposure. Additionally, the study did not assess the potential cumulative effects of multiple contaminants, which could have a synergistic impact on human health.


The exposure assessment case study conducted in Churchill County, Nevada, highlighted the presence of environmental contaminants and potential exposure pathways in the community. The study employed a combination of questionnaire surveys, environmental sampling, and biomonitoring to identify and quantify exposure to contaminants. Further research is necessary to establish a conclusive link between the identified exposures and the reported health issues in the community. The findings underscore the importance of conducting thorough exposure assessments to assess and manage potential risks to human health