QUESTION #1.
A Little Mystery.An industrial land fill was used from about 1880 until about 1950. It filled a small valley in the mountains and was almost on the banks of a medium sized river. It covered about 25 acres with an average depth of waste of 80 feet. In the 1980s several inhabitants in the area became ill with an unusual form of cancer. None had ever worked at the landfill or the industry. The area has private water wells and septic tanks. A very extensive investigation of health records was begun. A number of similar cases were found but those people lived away from the area and had only visited it as tourists or to fish. The nearest intake in the medium sized river for public water is 190 miles downstream. Now please answer the following questions about this case.
A. What pathway or pathways could have linked the land fill to the people living nearby who became ill?
B. How would you determine if a pathway actually worked to cause the illnesses?
C. Would you expect to find a problem in the city 190 miles downstream that uses the river for a water supply? Justify your answer.
D. What would you sample on this site?
E. Who should pay for the short-term and long-term corrective actions needed here?
QUESTION #2.
reference books to define LD50 and describe an experiment to determine this value. Explain what LD50 says about risk and toxicity.