Tokyo, Japan (SPX) Feb 08, 2011
Pharmaceuticals, illicit drugs, shampoo, toothpaste, pesticides, chemical run-off from highways and many other pollutants infiltrate the giant aquifer under Mexico's "Riviera Maya," research shows.
The wastes contaminate a vast labyrinth of water-filled caves under the popular tourist destination on the Yucatan Peninsula. The polluted water flows through the caves and into the Caribbean Sea. Land-sourced pollution may have contributed, along with overfishing, coral diseases, and climate change, to the loss since 1990 of up to 50% of corals on the reefs off the region's coast.
And, with a 10-fold increase in population through 2030 expected, the problems are likely to worsen, according to research published in the journal Environmental Pollution.
"These findings clearly underline the need for monitoring systems to pin-point where these aquifer pollutants are coming from," says Trent University Prof. Chris D. Metcalfe, Senior Research Fellow of the United Nations University's Canadian-based Institute for Water, Environment and Health (UNU-INWEH).
"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."
Dr. Metcalfe conducted the study with Patricia A. Beddows of Northwestern University, Evanston IL, USA; Gerardo Gold Bouchot of CINVESTAV Unidad Merida. Mexico; Tracy L. Metcalfe and Hongxia Li of Canada's Trent University; and Hanneke Van Lavieren of UNU-INWEH. The work was conducted with the cooperation of a local non-governmental organization, "Amigos de Sian Ka'an."
The researchers concluded that illicit drugs, pharmaceuticals and personal care products found in the groundwater at four of the five locations originated from domestic sewage.
The illicit drugs identified were cocaine and its major post-digestion "metabolite" chemical, benzoylecgonine.
Also found were caffeine and a metabolite of nicotine and the ingredients of personal care products such as:
Triclosan (an anti-bacterial agent used mainly in toothpaste, cleansers, and hand sanitizers); Synthetic musks (used in perfumes, deodorants, etc.); Non-prescription painkillers acetaminophen and ibuprofen.
The researchers point to pit latrines, septic tanks and leaking sewer lines as the pollution's likeliest points of origin, noting that just one-third of the state is served by municipal wastewater treatment systems.
Samples drawn near a golf course on a seaside resort, pointed to pesticide applications as another contamination source.
Polycyclic aromatic hydrocarbons (PAH) pollution, meanwhile, likely entered the groundwater as runoff from highways, parking lots, airport tarmac, and other solid surfaces.
Reverse osmosis systems for treating drinking water are widely used in the Riviera Maya, "but this technology is unlikely to remove all micro-contaminants," the study says.
While the levels of pollution found are not considered a health threat today, "the data provided in this study raise some concerns about the potential for human exposure from the consumption of contaminated drinking water."
The researchers note the area has "a general lack of expertise and equipment for monitoring or tracking sources of pollution," and "few administrative links between those responsible for water and coastal management and the labs that generate the (monitoring) data."
+ Impermeable liners installed beneath golf courses and other areas that are extensively covered with turf to restrict the leaching of contaminants, nutrients and pathogens;
+ Lined and impermeable drainage canals, retention ponds and treatment systems to deal with runoff in areas where liners have been installed;
+ Adequate wastewater treatment infrastructure;
+ A halt to injections of treated sewage into saltwater below the freshwater aquifer;
+ Measures to avoid aquifer contamination from hard surface runoff;
+ An integrated approach to coastal zone management; and
+ Protection of all remaining mangroves, which buffer coastal areas from pollution.
They warn too that a combination of sea-level rise and over-extraction of freshwater contributes to saltwater intrusion into the aquifers, posing a threat to the region's freshwater quality and availability.
Without integrated approaches to protecting and managing the aquifer, "the tourism-based economy of the Maya Riviera region will not be sustainable over the medium to long term," the researchers conclude.
They deployed two types of passive sampling devices in five locations at depths of 1.5 to 10.5 meters to sample groundwater flowing under the area at a rate of 0.5 to 2.5 km per day to measure concentrations of contaminants and determine possible sources.
The freshwater in these aquifers forms a distinct lens on top of intruding salt water. The two water layers meet and mix in these flooded cave systems, which extend 8 to 12 km inland.
The area's highly permeable geology, characterized by remarkable sinkholes offering access to the groundwater cave systems, makes the peninsula very susceptible to contamination.
"Diving down a sinkhole into these flooded cave systems was a truly unique experience - and slightly terrifying for someone diving in a cave for the first time," says Ms. van Lavieren, a programme officer at UNU-INWEH and trained rescue diver.
"It is hard to imagine the actual size and shape of these cave systems without actually being in them. Thankfully, we were helped by experienced divers in the area to deploy and collect the passive samplers."
Share This Article With Planet Earth
United Nations University
Water News - Science, Technology and Politics
China earmarks $303 bn for safe water: report
Beijing (AFP) Jan 21, 2011
China plans to invest $303 billion in water infrastructure projects over the next five years that would give millions of rural residents access to safe drinking water, state media reported. Severe flooding and droughts across the country last year destroyed crops and drove up food prices, pushing inflation to its highest level in more than two years, prompting the investment. Beijing wil ... read more
Australian MPs weep for disaster victims|
Disasters could reverse growth: Australia
Australia flags taxpayer levy for floods
Australia sends in troops after mega-cyclone
Bookstores feeling pain from digital technologies
Portable devices linked to US pedestrian death spike
NEC, Lenovo in talks on joint venture: report
Verizon reins in data hogs before unleashing iPhone
Hungarian plant still releasing toxic mud: Greenpeace
Native Brazilians plea for dam project to be scrapped
Pollutants In Aquifers May Threaten Future Of Mexico's Fast-Growing 'Riviera Maya'
Thailand closes dive spots due to reef damage
Norwegian house ratifies Arctic border agreement with Russia
VIMS Team Glides Into Polar Research
Greens: Alaska oil delay a win for polar bears
'Hidden Plumbing' Helps Slow Greenland Ice Flow
Helping Feed The World Without Polluting Its Waters
Argentina admits to malnutrition deaths
Bordeaux wines face climate threat: experts
Russia resumes sturgeon caviar exports to Europe
Sri Lankan floods return, death toll rises to 17
Sri Lankan floods pile on misery: UN
Torrential downpours pile misery on Australia
One million Sri Lankans hit by floods, 14 dead
Arms seized in Nigeria were for Gambia: Iran ambassador
China's finance minister visits Zimbabwe to bolster bonds
Mutiny by south Sudan ex-militiamen kills 20: army
African nations ride the possibilities of bamboo bikes
Study warns of climate-driven migration
Mathematical Model Explains How Complex Societies Emerge And Collapse
U.N.: World population rate must slow
'Tsunami' of obesity worldwide: study
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2010 - SpaceDaily. AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement|