Dear EarthTalk: I understand there’s an issue with the herbicide atrazine showing up in dangerous quantities in drinking water, mostly throughout the central U.S. Why is this happening and what’s being done about it? -- Marcus Gerde, Spokane, WA

Atrazine is an herbicide that is widely used across the

U.S.

and elsewhere to control both broadleaf and grassy weeds in large-scale agricultural operations growing corn, sorghum, sugar cane and other foods. While its use is credited with increasing agricultural yields by as much as six percent, there is a dark side. The nonprofit Natural Resources Defense Council (NRDC) reports that atrazine exposure has been shown to impair the reproductive systems of amphibians and mammals, and has been linked to cancer in both laboratory animals and humans. Male frogs exposed to minute doses of atrazine can develop female sex characteristics, including hermaphroditism and the presence of eggs in the testes. Researchers suspect that these effects are amplified when atrazine and other harmful agricultural chemicals are employed together.

Atrazine’s wide use makes its impacts that much scarier. NRDC reports that it is the most commonly detected pesticide or herbicide in

U.S.

waters, with the highest levels found in Indiana, Missouri and Nebraska. The Southeast also faces atrazine overload issues. What irks many public health advocates is that, even though study after study implicates atrazine in a long list of environmental and health problems, the U.S. Environmental Protection Agency (EPA) still allows farms to apply 75 million pounds of it each year. The European Union banned atrazine in 2004 due to persistent groundwater pollution there.

Critics of the EPA accuse the agency of selling out the health of the American people so industrial agricultural companies can make big profits. Indeed, in 2003, the EPA estimated a total annual economic impact, if atrazine were to be banned, of over $2 billion, including a yield loss plus increased herbicide cost averaging $28 per acre. In 2006, the EPA concluded that triazine herbicides (such as atrazine) posed “no harm that would result to the general

U.S.

population, infants, children or other...consumers.”

In light of the EPA’s refusal to consider a ban on atrazine, NRDC and other groups have taken up the cause of educating consumers about the dangers posed by our national addiction to dangerous herbicides and pesticides, and lobbying elected officials to add their voices. President Obama has promised to take a hard look at atrazine, but it remains to be seen how long it will be before any such review takes place.

Of course, organic farmers aren’t waiting around for Obama to ban atrazine. By planting diverse crops, rotating them regularly and employing other age-old agricultural techniques, a new generation of American farmers is learning that expensive chemicals may not be able to boost their yields enough to warrant the high financial and environmental costs associated with constant chemical spraying.

As for you and I, the best way to prevent ingesting atrazine with our tap water is to buy a water filter that employs activated charcoal. NRDC publishes a free list of water filter recommendations on its Simple Steps website. If you’re on a well, NRDC recommends having its water tested annually for atrazine and other contaminants. Even bottled water producers may not filter out atrazine from their source aquifers, so filtering at the tap is the only way consumers can be sure to remove it along with other contaminants.

CONTACTS: NRDC, www.nrdc.org; Simple Steps, www.simplesteps.org; EPA, www.epa.gov.

Dr. OZ: Top Travel Tips

Travel health troubles don’t care whether it’s business or pleasure. Avoid jet-lag and other aches and pains by following these tips.

Before you travel, plan some prior protein. The last meal before traveling should contain a good balance of protein and starch, so you will feel satisfied.

Avoid the salt and calorie-laden nibbles at the airport, or in-flight.

Remember, the air in planes is dry. So, drink non-alcoholic decaf beverages and water to avoid dehydration. And even healthy people can get blood clots in their legs after long flights.

Try to walk every now and then during your flight and stretch your calf muscles, even while you are sitting.

Finally, traveler’s constipation is a natural response to unfamiliar environments. Take in lots of fiber and water.

Safe and happy travels.

CEDARS-SINAI RESEARCH SHOWS ANTIBIOTIC PREVENTS IBS SYMPTOMS FOR WEEKS AFTER FINAL DOSE

Results confirm earlier Cedars-Sinai studies showing effectiveness of rifaximin against chronic IBS

A targeted antibiotic provides effective and long-lasting relief of Irritable Bowel Syndrome symptoms, according to the results of two multisite Phase III clinical trials designed by Cedars-Sinai researchers. Rifaximin is the first drug treatment for IBS that relieves symptoms while it’s being administered and continues to benefit patients after they stop taking the drug.

Researchers found that patients who took rifaximin not only experienced relief of their IBS symptoms, including specific symptoms of bloating, abdominal pain and stool consistency, while they were taking the antibiotic, but also that their relief was sustained over the 10 week follow-up period when no antibiotic was administered.

The results of the studies were presented at the Digestive Disease Week conference in New Orleans on May 3.

“These studies validate the role of altered gut bacteria in IBS,” said Mark Pimentel, M.D., GI Motility Program director at Cedars-Sinai and the principal investigator of the clinical trial at Cedars-Sinai. “These findings show that targeted antibiotics provide safe and long-lasting improvement for IBS patients.”

IBS is the most common gastrointestinal disorder in the United States, affecting more than 20 percent of the population. Traditionally, patients with IBS have been described as having “constipation predominant,” “diarrhea-predominant” or an alternating pattern of diarrhea and constipation. In addition to these symptoms, IBS patients often experience abdominal pain or cramps, excess gas or bloating, harder or looser stools than normal and visible abdominal distension.

Because the cause of IBS has been elusive, treatments for the disease have historically focused on relieving its symptoms through medications that either slow or speed up the digestive process. Earlier research conducted by Pimentel and colleagues documents a possible link between bloating, the most common IBS symptom, and bacterial fermentation by giving participants lactulose breath tests. The test monitors the level of hydrogen and methane – the gases emitted by fermented bacteria – on the breath. Those tests show elevated levels of those gases, indicating that small intestine bacterial overgrowth, or SIBO, may be a cause of IBS.

More than 1,200 patients participated in the Phase III, double-blind, multi-center studies of rifaximin, a nonabsorbable antibiotic that stays in the gut and is currently FDA-approved to treat traveler’s diarrhea and hepatic encephalopathy. IBS patients with mild to moderate diarrhea and bloating were randomized to receive 550 milligrams of rifaximin or placebo for two weeks. Patients were then followed for an additional 10 weeks. Phase III trials are randomized studies on large patient groups to definitively demonstrate the safety and effectiveness of a new drug.

The findings support previous research by Pimentel indicating that IBS is caused by an overgrowth of bacteria in the gut.

“Even after you stop the antibiotic, the patients continue to feel better, which indicates that we did something to strike at what causes the condition,” Pimentel said.

In addition to Cedars-Sinai, other centers participating in the clinical trials included Beth Israel Deaconess Medical Center in Boston, University of Michigan Medical Center in Ann Arbor, University of North Carolina at Chapel Hill, Connecticut Gastroenterology Institute in Bristol, Conn.

Rifaximin is marketed by Salix Pharmaceuticals, Inc. Salix also provided funding for the studies. Pimentel discovered the use of rifaximin for IBS, and Cedars-Sinai holds patent rights to this discovery and has licensed rights to the invention to Salix. Dr. Pimentel is a consultant to Salix, Inc, and serves on its scientific advisory board.

The American Academy of Orthopaedic Surgeons has joined forces with the hopaedic Trauma Association (OTA) on a public service announcement (PSA) urging drivers to NEVER text while driving. Simply put, texting is a deadly distraction that can cause accidents, severe orthopaedic injuries or even death. Orthopaedic surgeons not only treat, but want to prevent accidental traumas.

“The problem with the use of 24/7 communications devices is that every driver believes he or she is immune to slip ups, but isn’t. Orthopaedic surgeons want to prevent the pain and suffering associated with texting-and-driving accidents. To say this habit can be deadly is the truth; it is an outcome we unfortunately see every day,” said AAOS President John J. Callaghan, MD.

The ads -- meant to shock -- read “OMG. Get the Message: Texting while Driving is a Deadly Distraction” in large font over a broken, bloodied windshield. AAOS’ national public service advertising campaign was produced as a print PSA and a billboard. The ads are the first step in educating the public on what has become a commonplace and dangerous practice among drivers. Companion Web sites urge safer practices and shares vital statistics -- www.aaos.org/donttext and www.ota.org/donttext.

“This topic is on the minds of many Americans already – but we wanted to reiterate the traumatic outcomes and the risk involved with memorable images and shocking statistics. The magnitude of a distracted crash can change limbs, lives and futures forever,” said OTA President Timothy J. Bray, MD.

OMG and AAOS/OTA 2010
The 2010 OMG PSA campaign material will be distributed nationally to 1,500 print outlets, including both newspaper and magazines. In addition, the print public service messages will be featured on almost 500 display ads in airports and on outdoor billboards nationwide.

Is your chest pain a heart attack or something else? The Harvard Heart Letter discusses

That dull burning in your chest doesn’t seem to be going away, and it feels like it's getting worse. Is it a heart attack or something else? That’s a vexing question, one that millions of people and their doctors face each year. It’s a problem because chest pain can stem from dozens of conditions besides heart attack, from pancreatitis to pneumonia to panic attack, reports the May 2010 issue of the Harvard Heart Letter.

Doctors use several pieces of information to determine who is, and who isn’t, having a heart attack. The most accurate are blood tests for markers that show damage to the heart muscle, such as creatine kinase and cardiac troponin. But since it takes awhile for blood levels of these proteins to get measurably high, the best early methods are an ECG (electrocardiogram) plus the story and description of your chest pain and other symptoms.

The Harvard Heart Letter notes that it is more likely to be a heart attack if you experience

Women's health from age 50 on: A new special report from Harvard Medical School

Most people know the rock-bottom basics of good health: eat right, exercise, don’t smoke, get plenty of sleep. But there's actually more to staying healthy than that, especially for middle-aged and older women. A Guide to Women’s Health Fifty and Forward, a new Special Health Report from Harvard Medical School, addresses health issues of special concern to these women—osteoporosis, breast cancer, ovarian cancer, and microvascular disease (a type of heart disease that’s more common in women). It also offers advice on age-related health issues that are more bothersome than serious, including wrinkles, hair loss, and hot flashes.

Many women begin making more and more health-related decisions at midlife—when to have a mammogram, colonoscopy, or bone density test; how much to exercise; whether to take a bone-protecting medication; and more. A Guide to Women’s Health Fifty and Forward aims to help women take stock of their health at midlife, understand their health risks, and learn what they can do to stay healthy and strong.

Lifestyle choices, of course, are significant contributors to overall health. Women’s health studies have shown that it’s never too late to feel better by living better. Women who simply replace animal fats with vegetable oils in their diet cut their risk of heart attack almost in half. And according to one study, four lifestyle changes—stopping smoking, becoming more active, reducing blood pressure, and controlling diabetes—greatly reduces a woman’s likelihood of landing in a nursing home.

The report gives women important information and advice on such matters as these:

Dr. OZ: Top Travel Tips

Is your chest pain a heart attack or something else? The Harvard Heart Letter discusses

Women's health from age 50 on: A new special report from Harvard Medical School