HLTH 8034 Week 1 Scale Question Orientation Post Example

Week 1 Discussion: Introductions and an Environmental Health Problem

Nitrate in County Wells From Fields Across the Line: An Introduction, One Problem That Refuses a Single Boundary, and the Scale Question It Raises

I work in environmental health for a county in the Midwest, a composite I will call Alder County so that I can describe it frankly. My role meets three kinds of exposure most weeks: private well water, septic failures and the occasional complaint about odor or dust from livestock operations. Of the three, well water is the one that keeps me up at night, because the people affected usually cannot see, smell or taste the problem.

The problem I bring this term is nitrate in household wells. Over the past several sampling seasons, results from wells in the county's eastern townships have climbed toward, and in some homes above, the federal drinking water limit for nitrate. Our department's records point upstream: the shallow aquifer under those townships is recharged partly from farmland in the next county, where corn and soybean acreage receives heavy fertilizer applications each spring. The health concern is real. The federal limit exists chiefly to prevent methemoglobinemia in infants, and a review of the epidemiologic literature found evidence linking nitrate in drinking water to colorectal cancer, thyroid disease and some birth defects, in some studies at levels below the limit (Ward et al., 2018). Nationally, nitrate is among the contaminants most often found above health benchmarks in domestic wells, especially in agricultural areas (DeSimone et al., 2009).

What I have not settled is the scale at which the problem should be argued. At the scale of the well, it belongs to the household: federal drinking water law does not reach a private well, and testing and treatment are the owner's responsibility (U.S. Environmental Protection Agency [EPA], n.d.). Evidence at that scale is a single lab result. At the scale of the county, it belongs to my department, which can sample, map results and advise, but cannot regulate what happens on farmland across the line. At the scale of the groundwater basin, it belongs to whatever body manages the aquifer, and in some states such districts can require changes in fertilizer practice. The evidence there is a trend across many wells and years. Each choice hands the argument to a different authority, and I suspect the course will push me toward the basin while my job keeps pulling me back to the county.

Reply to Priya

Priya, you brought wildfire smoke reaching your city from forests two states away. At which scale would you argue it: your city's monitors, the state that issues alerts, or the region the smoke crosses? I ask because I could not decide for my own problem, and each answer gave a different agency the job. Your choice will also decide which monitors count as evidence.

Reply to Tomas

Tomas, your example of lead in school drinking fountains looks like a building-scale problem at first. Is it? If the lead comes from service lines owned by the utility, the scale might be the water system, not the school, and the responsible party changes with it. The evidence would change too: fountain samples at the building scale, service line records at the system scale.

References

DeSimone, L. A., Hamilton, P. A., & Gilliom, R. J. (2009). Quality of water from domestic wells in principal aquifers of the United States, 1991-2004: Overview of major findings (Circular 1332). U.S. Geological Survey. https://doi.org/10.3133/cir1332

U.S. Environmental Protection Agency. (n.d.). Private drinking water wells. https://www.epa.gov/privatewells

Ward, M. H., Jones, R. R., Brender, J. D., de Kok, T. M., Weyer, P. J., Nolan, B. T., Villanueva, C. M., & van Breda, S. G. (2018). Drinking water nitrate and human health: An updated review. International Journal of Environmental Research and Public Health, 15(7), Article 1557. https://doi.org/10.3390/ijerph15071557