Aquifers poisoned with drugs, chemicals and pesticides threaten Mexico's Riviera Maya
S. L. Baker, features Writer
But there's a major problem. Researchers have discovered that prescription and street drugs, chemicals from shampoo and toothpaste, pesticides, chemical run-off from highways and many other pollutants have infiltrated the giant aquifer under the Riviera Maya.
Bottom line: the water in the area is becoming poisoned.
Aquifers are the saturated zone beneath the water table and they are huge storehouses of groundwater. Wells can be drilled into aquifers to pump out the water. But water coming from the crucial Riviera Maya aquifer is quickly turning toxic.
Chemical waste has polluted an enormous labyrinth of water-filled caves under the area and the contaminated water flows out into the Caribbean Sea. Scientists fear this pollution along with over fishing, coral diseases, and possible climate change, has caused the loss of about half the corals on the reefs off the region's coast over the past 20 years.
In a study just published in the journal Environmental Pollution, a research team including scientists from the Canadian-based Institute for Water, Environment and Health (UNU-INWEH), Northwestern University, Unidad Merida of Mexico and Canada's Trent University discovered drugs (illicit, prescription and over-the-counter) and chemicals from personal care products in the groundwater originated at four of the five locations from domestic sewage. In other words, people are flushing chemicals right into the groundwater.
The major pollutants identified included cocaine and its major post-digestion "metabolite" chemical (benzoylecgonine), triclosan (an anti-bacterial agent used in toothpaste, cleansers, and hand sanitizers), synthetic musks (used in perfumes and deodorants), acetaminophen and ibuprofen. Polycyclic aromatic hydrocarbons (PAH) pollution discovered in the groundwater most likely came from runoff from highways, parking lots, airport tarmac, and other solid surfaces. Water samples drawn near a golf course were contaminated with pesticides, too.
Currently, drinking water is being treated with reverse osmosis systems in the Riviera Maya. Unfortunately, the study concluded, "...this technology is unlikely to remove all micro-contaminants."
And while the levels of pollution found are not considered a health threat today, the study authors noted: "The data provided in this study raise some concerns about the potential for human exposure from the consumption of contaminated drinking water... As well, prevention and mitigation measures are needed to ensure that expanding development does not damage the marine environment and human health and, in turn, the region's tourism-based economy."
The researchers' recommendations for dealing with the critical water contamination issues in the Rivera Maya include having impermeable liners installed beneath golf courses and other areas that are extensively covered with turf to restrict the leaching of contaminants, adequate wastewater treatment infrastructure, a halt to injections of treated sewage into saltwater below the freshwater aquifer, and measures to avoid aquifer contamination from hard surface runoff.
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Feb. 24, 2011