Biomedical Engineering Reference
In-Depth Information
100
Elevated inversion
50
Ground-based
inversion
0
0
5
10
15
Observed temperature (
°
C)
Figure
9.6
Two types of thermal inversions that contribute to air pollution.
thermal inversions in the atmosphere (Figure 9.6). The air quality has been characterized by the US
Environmental Protection Agency as seriously polluted, with brick making on the Mexican side identified
as a major source.
18
In Mexico, workers who make bricks are called “ladrilleros.” Many ladrilleros live in unregulated
shantytowns known as “colonias” on the outskirts of Ciudad Juarez. The kilns, using the same design
as those in Egypt thousands of years ago, are located within these neighborhoods, next to the small
houses. The ladrilleros are not particular about the fuel, burning anything with caloric value, including
scrap wood and old tires, as well as more conventional fuels like methane and butane. The dirtier fuels,
like the tires, release large black plumes of smoke that contains a myriad of contaminants.
Children are at an elevated risk of health problems when exposed to these plumes, since their lungs
and other organs are undergoing prolific tissue growth. Thus, the ladrilleros' families are at elevated
risks particularly due to their frequent and high dose exposures. “The health impact is not only of
concern to the worker but also the entire family, especially pregnant women and children who, because
of their socioeconomic status, tend to be undernourished,” according to Beatriz Vera, project coordinator
for the US-Mexico Border Environment and Health Projects. She adds that “many times the entire
family participates in the process. Sometimes children are put directly into the area where the kiln
is fired.”
The two nations' governments are at least somewhat cognizant of the problem, as are numerous
nongovernmental organizations (NGOs). These have included Environmental Defense (ED), Physicians
for Social Responsibility, the Federacion Mexicana de Asociaciones Privadas de Salud y Desarrollo
Comunitario (FEMAP), and El Paso Natural Gas (EPNG). For example, FEMAP and EPNG offer
courses to the ladrilleros from throughout the region on ways to use higher quality fuel, including
improved safety, and business practices as well. Often, however, even if the brick makers know about
cleaner fuels, they cannot afford them. For example, they have used butane, but in 1994 the Mexican
