Describe how you would conduct an ecologic study to examine whether the consumption of drinking water by residents of Flint, Michigan was associated with cancer risks.

Case Scenario
We have all been alarmed by the recent revelations about lead contamination in the potable water supply of Flint, MI homes. Lead is a heavy metal that is both naturally occurring and anthropogenic that is used in a variety of products; as a pesticide applied to fruit orchards until the 1950s and as an antiknock compound in gasoline until the early 1990s. The high levels now found throughout the environment are due to man-made activities. There are still active primary lead mines in parts of the United States, however; industries that use lead, for example, to make car batteries and ammunition also obtain lead from secondary sources such as battery recycling facilities. Healthy People 2020 has outlined the reduction to exposure to lead in the population as measured by blood and urine concentrations of the metal or its’ metabolites.

Lead poisoning is the number one environmental illness in children and although Illinois has made great strides to reduce the rates of lead poisoning in children, the state maintains one of the highest rates of children with elevated blood levels in the nation. The city of Chicago has seen the decrease and elimination of blood levels in several parts of the city, however; the rate of lead poisoning is up to six times higher than the city average in portions of poor, predominantly African- American neighborhoods. Health issues surrounding childhood lead poisoning contribute to lower intelligence, decreased ability to pay attention and underperformance in school. The current events transpiring in Flint, Michigan with hazardous exposures to lead in the drinking water supply have brought this issue to the forefront. Are the concerns about lead in Flint, Michigan an isolated incident? Is lead in children an important public health concern that we need to pay more attention to in larger cities?

Please answer the questions below in the order in which they are presented (see format for writing the comp exam). Be careful to align your answer with the case study as presented.

A. Epidemiology

Several epidemiologic studies have reported positive significant associations between the consumption of heavy metal contaminated drinking water and certain cancers. Assuming you are leading a team of epidemiologists to assess the effect of water contamination at Flint, Michigan:
i. Describe how you would conduct an ecologic study to examine whether the consumption of drinking water by residents of Flint, Michigan was associated with cancer risks.

ii. Describe inherent methodological limitations of ecologic studies and how you plan to address these limitations in your study.

iii. From your study the following results were generated:

Mean Annual Age-Adjusted Mortality Rates per 100,000 population and Ratios of Age-Adjusted Mortality Rates (RAMR)
Cancer Site
Community A
(Contaminated Water) Community B
(Clean Water) RAMR (95% CI)
All sites 135.66 103.09 1.32 (1.18 – 1.46 )
Rectum 3.45 2.43 1.42 (1.23 – 2.25)
Liver 36.45 29.37 1.49 (0.93 – 2.40)
Bladder 4.85 2.60 1.86 (1.54 – 3.50)
Kidney 1.73 0.69 2.51 (1.27 – 4.94)

(a) Explain these hypothetical results to a group of professionals at attending an APHA conference in Denver Colorado.

(b) You have been invited by the Michigan state senate ad hoc committee on Flint Water Disaster to give scientific evidence of effect of water contamination on the health of people. Use this hypothetical results as evidence-based report to argue for emergency funding for water decontamination.

Biostatistics
Assume that you have the following hypothetical data (see 2016_Bio_Data.xls). Use the data to complete the following tasks.

i. Generate the descriptive statistics and perform an appropriate statistical analysis to determine whether there is a relationship between percent of household below poverty level and childhood lead poisoning rate across the Flint neighborhoods.

(a) Interpret your statistical results and create tables/figures in accordance with the APA guideline for the professional audience.
(b) Also, briefly address the results and their impacts written for a lay audience.

ii. Investigate whether the percent of household below poverty level predicts the childhood lead poisoning rate across the Flint neighborhoods.

(a) Interpret your statistical results and create tables/figures in accordance with the APA guideline for the professional audience.
(b) Also, briefly address the results and their impacts written for a lay audience.