Environmental Science, 10th Edition (Cunningham)

Chapter 8: Environmental Health and Toxicology

GE Exercise: Melvin Iowa, Corn Belt Landscape

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An overview manual is available by clicking here... Google Earth Overview (342.0K)

To continue:
- Make sure you have the Google Earth software installed and running.
- Copy the following latitude and longitude and paste into the "Fly to" field under the Search tab.
- Hit “Enter” for Google Earth to take you to the specified coordinates, then come back here and read the following overview.

Latitude/Longitude: 43.2739, -95.6232

Overview: Melvin Iowa, Corn Belt Landscape, p. 169

Exposure to farm chemicals is an important health risk in many areas. Iowa is at the center of the American corn belt, where farming dominates the economy and the lifestyle of farming families and communities. Nitrites from fertilizers occur in drinking water supplies for many farms and small towns and present a risk to small children. Many pesticides also contaminate ground water and local streams. Atrazine, for example, which is widely used to control weeds in corn, can be found in water throughout this area. Evidence in lab animals suggests that this herbicide can disrupt endocrine functions and developmental processes at very low levels. Farmers who use conventional pesticides and herbicides have significantly higher rates of cancer than those who don't work with these chemicals.

1
The landscape here was surveyed in 1-square mile sections. Many farms consisted of one or more quarter sections (1/2 mile × 1/2 mile), although many farms have been consolidated and combined in recent years. Move north of the marker until the photo imagery becomes high resolution. Using your measuring tool, figure out how many houses there are per square mile in this area.
A)In general there are 0 to 5 houses per square mile.
B)In general there are 5 to 10 houses per square mile.
C)In general there are 10 to 20 houses per square mile.
D)In general there are 20 to 30 houses per square mile.
E)In general there are 30 to 50 houses per square mile.
2
Zoom out and get a sense of how much area is covered by this settlement pattern, with widely scattered houses every half mile or so in all directions. Why would farm chemicals such as Atrazine be a significant public health hazard in this area?
A)There is no reason to believe Atrazine would be a significant public health hazard in this area.
B)By zooming out, one sees that the landscape of the wider corn belt is quite divergent from this one local area, therefore it would be a mistake to assume any correlations exist regarding health hazards.
C)Even though it is called the "corn belt", not much corn is actually planted these days, so Atrazine is an insignificant health issue.
D)This farming landscape covers most of this region of the continent. Throughout this landscape, the risk of exposure to farm chemicals affects a large population, including anyone who drinks well water or works with chemicals.
E)Atrazine isn't water soluble, so it's unclear why it is considered dangerous.
3
Which of the following are reasonable ways to reduce exposure to farm chemicals in rural communities?
A)Make farmers wear hazmat suits
B)Reduce the use of chemicals and switch to alternative farming methods
C)Ban the use of agricultural chemicals
D)Relocate families away from farming areas
E)Develop new drugs that counter the effects of exposure to chemicals
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