Mexico City's smog is fecal matter

But Don`t Breathe The Air
October 17, 1985|By Edward Flattau. (copyright) 1985, Edward Flattau. Edward Flattau is a Washington-based columnist who specializes in environmental issues.
Mexico City has become one of the few places in the world where it`s possible to contact dysentery just by breathing the air.

The conventional mode of transmission for parasitic diseases is contaminated water or food, so people with access to adequate sanitation facilities usually are safe. But when the parasites manage to invade the atmosphere, no one can be secure.

Health-threatening air pollution has been a fact of life in Mexico City for two decades and is a major reason U.S. Embassy employees there receive hazardous duty pay. Pollutants from factories, automobiles and homes have created a virtually perpetual haze that obscures the surrounding mountains.

But although these pollutants can put dangerous stress on respiratory systems, particularly those of the elderly, sick and very young, they are not in and of themselves carriers of disease. That contrasts with the particles of dried human fecal matter that first began to be detected in Mexico City`s air some 15 years ago.

These contaminants come from the open dumps that were repositories for human waste in the squalid slums that ring the city. During dry period when winds sweep down from the nearby mountains, the fecal matter is blown out of these shantytown pits and across the city in a cloud of dust. Because many of the producers of this waste are in poor health, the particles contain numerous pathogens, including dysentery-producing micro-organisms and salmonella.

Though the Mexican government has been more or less officially silent on the matter, Dr. Umberto Bravo, one of Mexico`s most respected air pollution scientists, has recently been conducting research that confirms the worst fears about airborne parasitic disease. He has found increasing concentrations of pathogens in the city`s air and has even extracted some unsavory cultures from air samples.

Ironically, the recent devastating earthquakes have furnished one of the few glimmers of hope for solving the city`s horrendous air pollution problems. The Mexican government has announced that it will not rebuild any of the 450 buildings demolished during the catastrophe, and will create parks and monuments on the cleared sites instead.

Many of the razed structures were factories, which the government says will be relocated elsewhere in Mexico; the hope is that this shift will prompt more than a million city dwellers to move to the hinterlands.

Officials appear to be using the earthquakes to trigger what they could not launch on their own--the decentralization of the crowded capital before it literally as well as figuratively chokes itself to death.