MEXICO CITY — It's a simple warning — don't drink the tap water — and Mexicans take it to heart as much as any foreign tourist does.
Mexicans drink more bottled water than the citizens of any other country do, an average of 61.8 gallons per person each year, according to the Beverage Marketing Corp., a consultancy. That's far higher than Italy, and more than twice as much as in the United States.
A rising mistrust of tap water is behind the thirst for bottled water. Other factors are also at play, however, including clever advertising campaigns by multinational corporations and the failure of the Mexican government to provide timely data on water safety.
The boom in bottled water has an underside, too. Empty plastic water bottles litter landfills and roadsides at a rate that alarms consumer and environmental groups. Recycling experts say that only about one-eighth of the 21.3 million plastic water and soft drink bottles that are emptied each day in Mexico get recycled.
Mexicans weren't always as distrustful of tap water as they are these days.
"Twenty years ago, there were drinking fountains in all the public schools and in most parks," said Claudia Campero, a Mexico representative of Food & Water Watch, a Washington-based consumer advocacy group. Now, such fountains are rare.
Some municipal water systems in Mexico have fallen into disrepair, including in the capital, where a 1985 earthquake that killed more than 10,000 people broke numerous water mains. The city siphons water from the underlying aquifer faster than rainfall can replenish it, causing the city, much of which is built on an ancient lakebed, to sink, which puts additional stress on leaky water mains. Some 30 percent of the city's water is lost to leakage.
"The infrastructure is very old and obsolete. Even though there has been investment, it isn't enough. Runoff is seeping into the water system," said Octavio Rosas Landa, an economist at the National Autonomous University of Mexico.
For years, many residents grew accustomed to boiling tap water to ensure its safety, but natural gas prices have risen, making boiling expensive.
Not all the water is bad. Some provincial cities have improved their water systems, and Environment Ministry officials say that 85 percent of the water coursing through municipal systems is potable. Consumers, however, don't know when they might sip the other 15 percent. Many Mexicans simply don't trust the government to deliver clean, pure water.
That's where multinational companies with bottled water divisions — such as Coca-Cola, PepsiCo, France's Groupe Danone and the Swiss giant Nestle — have found an opening.
"These companies tell people to have confidence in them rather than in the government," Campero said.
One can hardly turn on the television without seeing an ad of a lithe young woman in a sweatsuit sipping from a bottle of premium water or a woman in a bikini whose svelte physique seems due to the bottle of water in her hand.
"Drink 2 liters of water a day," the ads from Bonafont, a leading brand from Danone, say in block letters at the bottom of the screen. Another ad says: "Eliminate what your body doesn't need."
"The competition is very intense," said beverage analyst Ana Paula Pedroni of the IXE brokerage. "The trend is for more marketing."
On street corners, vendors hawk liter bottles of water. Restaurants don't offer tap water, insisting that diners buy bottled water. Primary school students must take money to buy bottled water from kiosks. One brand uses characters from Looney Toons to appeal to the student market.
"Most of my students carry bottles of water, and they drink a lot with this heat," said Rosas Landa, the university economist and water expert.
For big companies, the boom in bottled water consumption in developing countries such as Mexico, India, China and Indonesia has been a godsend, since consumers in Europe, a stronghold of bottled water, have rebelled against throwaway plastic bottles as harmful to the environment.
Not so in Mexico. Former President Vicente Fox, a longtime Coca-Cola executive, looked positively on rising soft drink and bottled water sales, seeing them as a driver of economic growth. Mexicans drink an average of 42.3 gallons of soft drinks per capita annually, surpassed only by U.S. consumers.
The growth of soft drink consumption is slowing in comparison with water, however.
"The sale of water has risen on the order of 8 percent, while soft drinks rose 2 percent," Pepsi Mexico President Juan Gallardo Thurlow announced in early April.
The Beverage Marketing Corp. in New York City says Mexico's bottled water market composes 13 percent of the world's total, and has grown at 8 percent for each of the past five years.
Consumer advocates say Mexicans' thirst could be quenched more easily and inexpensively if municipalities provided reliable drinking water.
"The state has contributed to these companies taking over the market and converting drinking water into a saleable product," said Alejandro Calvillo, the head of Power to the Consumer, a nonprofit Mexican advocacy group.
Calvillo's group estimates that the average Mexican family spends $140 a year on bottled water, much of it in 5-gallon plastic jugs that are commonly delivered to homes. The expense puts a heavy burden on low-income families, he added.
In impoverished neighborhoods in outlying Mexico City, scores of private water companies have popped up, offering large jugs of water for 10 pesos, or about 77 U.S. cents, a third of the price of water from the multinational companies. Such concerns face few inspections, giving consumers water of indeterminate quality.
Further, most Mexican consumers refuse to separate plastic products for recycling, and those who seek to recycle can struggle to find places that'll accept post-consumer plastic.
"The corporations make the consumers responsible for recycling," Rosas Landa said. "They produce the containers, but don't take responsibility for recycling the bottles."
A Houston-based recycling services company, Avangard Innovative Ltd., joined with a Mexican environmental services company last year to open a $35 million recycling plant in Toluca to handle PET, polyethylene terephthalate, the strong, light plastic that's resistant to heat and impermeable to carbonation, making it perfect for beverages.
Still, Calvillo said: "A large part of the PET bottles that are collected are sent to China for recycling." The Chinese plants grind PET bottles into fibers for use in carpeting and other consumer products to sell to countries such as Mexico.
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