Cocaine, spices, hormones found in drinking water
This story is part of a special series that explores the global water
crisis. For more clean water news, photos, and information, visit
National Geographic's Freshwater Web site.
How's this for a sweet surprise? A team of researchers in Washington
State has found traces of cooking spices and flavorings in the waters of
Puget Sound.
University of Washington associate professor Richard Keil heads the
Sound Citizen program, which investigates how what we do on land affects
our waters.
Keil and his team have tracked 'pulses' of food ingredients that
enter the sound during certain holidays. For instance, thyme and sage
spike during Thanksgiving, cinnamon surges all winter, chocolate and
vanilla show up during weekends (presumably from party-related goodies),
and waffle-cone and caramel-corn remnants skyrocket around the Fourth of
July.
The Puget Sound study is one of several ongoing efforts to
investigate the unexpected ingredients that find their way into the
global water supply.
Around the world, scientists are finding trace amounts of substances,
from sugar and spice to heroine, rocket fuel, and birth control, that
might be having unintended consequences for humans and wildlife alike.
Vanilla Seas
When spices and flavorings are flushed out of a US home, they travel
to a sewage-treatment facility, where most of them are removed.
In the area around Puget Sound, the University of Washington team
found, the spicy residues that remain in wastewater end up flowing into
the sound's inland waterways.
Of all the flavors trickling downstream, artificial vanilla dominates
the sound, Keil said. For instance, the team found an average of about
six milligrams of artificial vanilla per liter of water sampled.
The region's sewage runoff contains more than 14 milligrams of
vanilla per liter. This would be like spiking an Olympic-size swimming
pool with approximately ten 4-ounce (113.4-gram) bottles of artificial
vanilla.
For now, there's no evidence that a sweeter and spicier sound is a
bad thing, salmon, which can smell such flavors, could be enjoying their
vanilla-enhanced habitat, Keil said.
In an attempt to understand some of the consequences of spice in the
water, Keil and colleagues plan to study whether cooking ingredients
harm the reproduction of octopuses in Puget Sound.
Overall, he added, the spice project has become a successful recipe
for educating people, especially school kids, 'that everything you do is
connected to the watershed'.
Illegal drugs
The link from kitchen or bathroom to coast can also grease the path
for some rather unsavory substances, such as illegal drugs, experts have
discovered. After a person has taken drugs such as cocaine, heroin,
marijuana, and ecstasy, active byproducts of these substances are
released into the sewage stream through that person's urine and feces.
These byproducts, or metabolites, are often not completely removed
during the sewage-treatment process, at least in Europe, said Sara
Castiglioni of the Mario Negri Institute for Pharmacological Research in
Milan, Italy. That means the drug-tainted wastewater can enter
groundwater and surface water, which are collectively the major sources
of drinking water for most people.
In a new review study, Castiglioni and colleague Ettore Zuccato found
that illegal drugs have become 'widespread' in surface water in some of
Europe's populated areas.
For instance, in a 2008 study scientists discovered a byproduct of
cocaine in 22 of 24 samples of drinking water at a Spanish
water-treatment plant, despite a rigorous filtering and treatment
process.
Likewise, in 2005, Zuccato found that a daily influx of cocaine
travels down the Po River, Italy's longest river. Though these drug
traces are still tiny, it's possible that the potent residues could be
toxic to freshwater animals, according to the study, which will be
published in an upcoming issue of the journal Philosophical Transactions
of the Royal Society A.
For this reason, the 'risks for human health and the environment
cannot be excluded', the study warns.
Pharmaceuticals
Scientists are also developing a clearer picture of how legal
pharmaceuticals and personal-care products, from antibiotics and
morphine to fragrances and sunscreen, are flooding our waterways.
For example, previous research had revealed that up to 44.1 pounds
(20 kilograms) of pharmaceuticals flow down Italy's Po River each day.
Much like illegal drugs, traces of pharmaceuticals often filter through
traditional sewage-treatment processes. These products are also found in
many US waterways, and studies have shown that certain drugs may cause
harm to the environment, though no evidence to date has shown effects in
people, according to the US Environmental Protection Agency.
Some of the drugs that mimic hormones, such as birth control, may
also throw off an animal's endocrine, or hormone-regulating, system.
Some male fish in the US, for example, have been growing female parts
due to exposure to estrogen in the water.
Christine Dell'Amore, National Geographic News |