Chapter 3.5: Industrial Smokestack Pollution

Metal smelters, which separate valuable metals like gold, copper, zinc, and cadmium from the ores they are found in, can have substantial impacts on environmental quality.  Smelting, which involves heating mineral ores with chemicals that act as reducing agents, can release large quantities of metals and other pollutants into the atmosphere as well as producing solid waste in the form of tailings.  As a result, smelters that lack effective pollutant removal technologies can have significant effects on human health and surrounding ecosystems.  Among the important pollutants released is SO2, which can react in the atmosphere to form acidic deposition.  This process has contributed to widespread acidification of aquatic and terrestrial ecosystems in some parts of the world. 

Before you start this case study, visit the web sites listed here to review the basics on smokestack pollution.

Background Materials:

To learn more about the nature of air pollution emitted by smelters, review these two cases:
Tacoma, Washington:
Zlatna, Romania:

To review the basics of acidic deposition, follow this link:

To view the video on the La Oroya smelter, follow this link:

Textbook References and Links:

Exercises 2 and 3:  Soto-Jimenez and Flegal study on lead contamination in Torreon:

Exercise 4: go to the following sites for information on Doe Run smelters and transboundary pollution:
Duke Law School paper on transboundary pollution:

Exercises 5 and 6: information on the West Dallas TX smelter case:

Exercise 7:  articles about red spruce decline in the northeastern US:

1983 paper that provides insufficient evidence to link acidic deposition to spruce decline:
1999 study of the effects of acidic deposition on forest health:
2012 study presenting evidence of a potential recovery of spruce-dominated ecosystems following enactment of the Clean Air Act by the US Congress.


Downloadable data and files:

Exercises 2 and 3:  Soto & Flegal 2011.pdf

Exercise 4: Duke Law Journal 1997.pdf

Exercise 7: 1983 spruce paper.pdf,  1999 spruce paper.pdf and 2012 spruce paper.pdf