New research reveals that some common food additives behave like estrogen in the body.

A discovery that two commonly used food additives are estrogenic has led scientists to suspect that many ingredients added to the food supply may be capable of altering hormones.

More than 3,000 preservatives, flavorings, colors and other ingredients are added to food in the United States, and none of them are required to undergo testing for estrogenic activity, according to the Food and Drug Administration.

“We need to be mindful of these food additives because they could be adding to the total effect of other estrogen mimicking compounds we’re coming into contact with,” said Clair Hicks, a professor of food science at the University of Kentucky and spokesperson for the Institute of Food Technologists, a nonprofit scientific group.

“The benefits of using these additives in food need to be weighed against the risks they present,” Hicks said.

In a study published in December, Italian researchers screened 1,500 food additives using computer-modeling software, a much faster and cheaper approach than testing lab rats.

The researchers first used modeling to identify 13 molecules that could hypothetically bind with an estrogen receptor, a group of molecules activated by the hormone. Like a clenched fist that fits into the palm of a hand, potentially estrogenic molecules will “fit” inside the receptor, indicating they could interact and alter hormones.

Then, the researchers exposed cells to the 13 food additives, which confirmed that two have estrogen-mimicking properties. Known as “xenoestrogens,” these substances have been linked to reproductive problems in animals and perhaps humans.

The first food additive, propyl gallate, is a preservative used to prevent fats and oils from spoiling that can be found in a range of foods including baked goods, shortening, dried meats, candy, fresh pork sausage, mayonnaise and dried milk.

The second additive, 4-hexyl resorcinol, is used to prevent shrimp, lobsters, and other shellfish from discoloring.

“Some caution should be issued for the use of these two additives,” said Pietro Cozzini, one of the researchers who conducted the study and a chemistry professor at the University of Parma in Italy.

He added that further tests on rats are necessary to determine whether these additives could harm humans.

Paul Foster, whose research focuses on the potential human health effects of endocrine disruptors, agreed. He said there is a big difference between adding estrogenic molecules to cells in a culture dish and actually seeing what happens when that dose is administered to an animal.

“There are a lot of compounds that give quite strong responses in a culture dish that really don’t produce any effects on lab rats,” said Foster, who is deputy director of the National Toxicology Program’s Center for the Evaluation of Risks to Human Reproduction, which is part of the National Institutes of Health.

The major concern, Foster said, is what happens when people are exposed to mixtures of these estrogenic compounds.

“There are examples where you can take dose levels of compounds on their own that won’t produce an effect, but when you put these compounds together, you may get something different,” he said.

However, Foster said people should keep in mind that they already ingest significant numbers of fairly potent estrogens in their diets by consuming foods like tofu and milk, so findings like these shouldn’t necessarily scare people until more research has been conducted.

“It’s clear that humans are exposed to a mixture of these estrogenic compounds,” Foster said. “But you have to try to balance out what might already be present in your diet or your lifestyle with these things that might be coming from some other sources,” such as food additives.

Systems like the one used by the Italian researchers are useful for screening potentially estrogenic additives, Foster said, adding that it’s a “good first step” towards identifying these compounds.

Of the estimated 3,000 additives used in the United States to preserve foods or improve their taste and appearance, only about 2,000 have detailed toxicological information available, according to the FDA.

“Our results are part of a bigger, more important problem, which is that there could be other additives used in foods that could have estrogenic activity,” Cozzini said.

Globally, the market for additives is expected to reach more than $33 billion by 2012. There are five main reasons that companies add compounds to food: to emulsify, to preserve, to add nutritional content, to add flavor or color and to balance alkalinity and acids.

“With some 3,000 compounds being used in food formulations there may be other additives with estrogenic properties that come to light with these types of studies,” Hicks said.

Using the traditional animal testing system, “it would be impossible to test all of the additives in a short time,” Cozzini said. “Every day we discover new molecules, and we must continue to identify new ways to study them.”

Propyl gallate is considered “Generally Recognized As Safe” (GRAS) by the FDA, a title given to food additives that don’t require approval because they have a proven track record based on either a history of use before 1958 or on published scientific evidence. Examples of other GRAS substances include salt, sugar, spices and vitamins.

The other estrogenic one, 4-hexyl resorcinol, which is used on raw shelled seafood to inhibit melanosis, or black spots, was petitioned in 1990 for GRAS status. Its status is still pending, according to Michael Herndon, an FDA press officer.

The FDA’s lack of testing for estrogenic compounds doesn’t stop at additives. In 2008, an independent advisory board said the FDA ignored critical evidence concerning another estrogenic compound, bisphenol A, a plasticizing chemical found in polycarbonate baby bottles and the linings of metal foods cans.

“What we’ve seen with the FDA’s handling of BPA is that it’s had its head in the sand,” said Renee Sharp, director of the Environmental Working Group’s California office. “If you look at its assessments, what you see is that it has consistently ignored independent science and consistently used outdated methods in its assessments.”

As concern about the cumulative impacts of these chemicals grows among the scientific community, some studies are suggesting that the effects of these compounds could extend to future generations.

For example, investigators at the National Institute of Environmental Health Sciences have found that adverse effects can be seen in both the granddaughters and grandsons of mice who were developmentally exposed to diethylstilbestrol (DES), a synthetic form of estrogen that caused reproductive problems in pregnant women and their fetuses. While DES was taken off the market in 1971, there are many other compounds that have similar, estrogenic effects.

“This study is the flagship of estrogen mimickers and why we worry about them,” said Shanna Swan, director of the University of Rochester’s Center for Reproductive Epidemiology and a leading expert on reproductive effects of environmental exposures. “The fact that these chemicals can effect future generations has been a huge lesson for the science community.”

Other research has found that low doses of these chemicals can cause significant changes in those exposed to them and their developing offspring. One recent study published in Environmental Health Perspectives found that when rats are exposed to low levels of BPA during lactation, their offspring had an increased chance of breast cancer.

As the evidence that synthetic estrogens may pose a health risk mounts, researchers are uncovering these compounds in new places.

Earlier this month, researchers in Germany found traces of an unknown estrogenic substance leaching into mineral water stored in polyethylene terephthalate (PET) bottles, a commonly used plastic for storing foods and beverages.

The study is the first to find that these containers are leaching synthetic estrogens.

“We already knew that BPA was leaching from polycarbonate baby bottles, so we decided to test bottles of mineral water to see if there was any estrogenic activity,” said Martin Wagner, a PhD student in aquatic toxicology at Johann Wolfgang Goethe University in Frankfurt.

The scientists tested 20 brands of mineral water and found that 60 percent of the samples tested positive, with estrogenic activity in plastic bottles appearing twice as high as compared to activity in water from glass bottles.

In addition, the researchers found that mud snails placed inside the bottles filled with fresh water experienced reproduction rates double of control snails, which suggests that substances from the packaging, and not the water itself, caused the reproductive change.

“The results show that these leached chemicals are important enough to change reproduction in only eight weeks,” Martin said.

Further testing is needed to identify the source of the estrogenic activity, but Wagner said the study’s significance is that it shows people are exposed to more environmental endocrine disruptors than what was previously thought.

“We’re dealing with this chemical mixture, a cocktail effect, and I would say that if you look at a single compound then you might underestimate the exposure to these environmental estrogens,” he said.

Ralph Vasami, executive director of a plastics industry group, the PET Resin Association, said ongoing research on the safety of PET for the past three decades has revealed no safety issues or reasons for concern.

“PET has been proven through considerable research to be a safe packaging material for water and other food and beverage items,” he said. “The PET industry stands on its record of safety and reliability as a packaging material.”

Swan said that the studies reinforce the need for precautionary action when dealing with these types of chemicals, such as avoiding plastic products whenever possible to decrease exposure.
“If you’re taking several hits of something, even if it’s safe at a low dose, it’s going to add up,” Swan said.

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Full article: http://www.sciam.com/article.cfm?id=food-additives-mimic-hormones&sc=WR_20090331

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I never really got to know the young woman. I met her during my third-year psychiatry rotation, when our team was consulted for concerns about depression.

Privacy rules won’t allow me to use her name (where possible, I’ve gotten consent from the others involved in this story). She was terminally ill, sick not just with the disease but with all the complications of its treatment, and confined to bed in the intensive care unit.

By the time I met her she could barely speak. Her face was a vacant yellow moon, and her sparse, colorless hair sprawled tangled and sweat-soaked across her pillow.

What I did come to know of her was through her boyfriend, Josh. They had been together since middle school and had stayed together even as the rest of her life fell apart.

When her strained relationship with her parents became impossible and they were no longer in her life, Josh remained her confidant and closest friend. When she learned she was seriously ill, she and Josh filled out the paperwork required to give him her durable power of attorney.

So it was that he sat by her bed day after day, occasionally rising from his post there to perform the rudimentary maintenance that she no longer could: wiping the tears from her eyes and clearing the caked secretions around her mouth.

In her medical chart, he is referred to not as her “boyfriend,” but as “family” or even simply as “Josh,” and his presence in her record traces much of the agonizing march of her illness.

As she takes a turn for the worse: “Josh feels that [the patient] is still fighting and would like to proceed with treatment.”

As organ systems begin failing: “Family will readdress code status tomorrow.”

And finally, as supportive medical care is withdrawn: “Josh understands that [she] is dying and states that he is struggling to imagine a future without her.”

•

Five months later, in the dead of winter, a 25-year-old man named David was changing a flat tire on the side of the road when he was struck by a van. He landed in the I.C.U. on a ventilator, with multiple fractures. I had landed there just several days earlier in my capacity as a medical student, and I would follow him as my patient for the next several weeks.

He soon became medically stable enough to move to a general hospital floor, but he had significant behavioral problems that required a sitter to stay with him around the clock. He routinely removed his feeding tube, refused to work with therapists, would not use a bedpan. He was frustrating and difficult to work with, and he was sabotaging his own recovery.

One morning I spoke with his nurse about his progress. His feeding tube had been in place for 30 hours straight. He had begun to cooperate in physical therapy, and he was using the bedpan without complaints.

David’s mother emerged into the hallway to confirm his improvement. It seemed to her to have a lot to do with the sitter who had been assigned to him for the past couple of days.

The sitter, she said, was extremely patient. He was supportive and enthusiastic, listening to David’s stories and sharing stories of his own. He was someone David could relate to, a perfect fit for him. I nodded, encouraged, and walked into the room.

There was David, sitting up in his hospital bed, animated and joking with his sitter. The thick, tedious air that had occupied David’s room effervesced and became light, and it happened so quickly I could not catch my breath.

His sitter was Josh.

It turned out he had taken a job with the hospital after his girlfriend’s death. His story, I realized, was a kind of love story, and in some way it evoked all of our stories, whether we are doctor or patient, comforter or comforted, healer or healed. Josh reaffirmed for me what we medical professionals know but all too easily forget: the human story is not a series of illnesses and treatments that we manage, but is an unfolding mystery — a process with which we ourselves are in ongoing communion, as both witnesses and full as participants.

There, settling into our place in the story, we can see it in its wholeness and let it make us whole. We take part in its healing as it unfolds, and we are healed by its unfolding.

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Full article and photo: http://www.nytimes.com/2009/03/31/health/31case.html?_r=1

Yosemite National Park may be known for its towering granite cliffs and booming waterfalls, but when temperatures drop and snow falls, the park changes personality.

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Morning: Upper Yosemite Falls

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Morning: Rising sun casts shadow on Yosemite Valley

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Evening: Pohono Bridge over the Merced River

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Evening: Yosemite Valley, from the Wawona Tunnel

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Evening: An icy reflection

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Evening: Trees in Stoneman Meadow against a granite wall

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Evening: Setting sun lights up El Capitan

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Evening: Aspen trees in Stoneman Meadow

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Full article and photos: http://www.latimes.com/travel/la-trw-yosemite,0,5845273.special

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In a world first, a rare baby cheetah owes its life to a doctored recording of a recently discovered male call that triggers ovulation.

Kenya, a first-time cheetah mom, gave birth to the healthy female cub on February 18 at the San Diego Zoo’s Wild Animal Park, park officials announced earlier this month.

The cub is a direct result of research reported earlier this year describing a male vocalization called a stutter-bark.

Scientists at the park’s Conservation Research had found that male stutter-barks trigger females’ reproductive systems to start releasing eggs.

The finding was a potential boon, as cheetahs can be difficult to breed in captivity because females don’t have regular ovulation cycles.

But there was still a catch: In captivity, certain females need to mate with particular males to maintain genetic diversity among the big cats.

Vocal Competition

Traditionally, scientists have found that their “arranged marriages” for the cheetahs don’t always suit the animals’ fancies—a situation that could have been aggravated by the fact that the recorded stutter-bark was from the park’s dominant male cheetah.
If a female cheetah heard the call of the dominant—and probably more desirable—male, she might reject the male chosen for her as a good genetic match, the scientists feared.

“To compensate for this, I modified the dominant male stutter-bark call slightly using an acoustic software program,” said Matt Anderson, the lead bioacoustics researcher on the project.

The software produced a stutter-bark that sounded authentic but was totally different from the calls of any of the park’s males.

The audio manipulation not only worked, it surprised the scientists by inspiring a bit of the real thing.

“We were delighted when the stutter-barks from this ‘new’ member of the cheetah group stimulated all our males to start stutter-barking themselves,” Anderson said.

“The females heard these calls and started breeding with the males that we wanted them to breed with.”

Shortly afterward Kenya was found to be pregnant, and three months later she gave birth to a single, as-yet unnamed cub.

Since inexperienced cheetah moms often have trouble rearing a lone baby, animal care staff decided to hand-raise the newborn.

Park staff are hopeful that the success could lead to more captive cheetah births in the future.

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Full article and photo: http://news.nationalgeographic.com/news/2009/03/090324-cheetah-birth.html

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As the smallest known frog species in the world’s second largest mountain range, this new amphibian is easy to miss.

But scientists searching the Andes mountains’ upper Cosnipata Valley in southern Peru, near Cusco, spotted the coin-size creature–a member of the Noblella genus–in the leaf litter of a cloud forest between 9,925 and 10,466 feet (3,025 and 3,190 meters).

The most distinctive character of the new species,” scientists write in the February issue of the journal Copeia, “is its diminutive size.” Females grow to 0.49 inch (12.4 millimeters) at most. Males make it to only 0.44 inch (11.1 millimeters).

What’s most surprising is that the frog lives at such high elevations, said study co-author Alessandro Catenazzi, a postdoctoral researcher at the University of California, Berkeley. In general, larger animals are found at greater heights.

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Full article and photo: http://news.nationalgeographic.com/news/2009/03/photogalleries/smallest-frog-pictures/index.html

The financial crisis is ending the new president’s German honeymoon.

Is the financial crisis for Angela Merkel what the Iraq war was for Gerhard Schröder — namely, a reason to seriously strain Germany’s relationship with the U.S.? One need not answer with an unconditional “yes” to be very concerned.

Naturally, at the G-20 meeting in London this week, Europeans will celebrate and praise the new American president. There will be beautiful photo opportunities and demonstrative unity. But the dispute behind the scenes has gotten worse. Barack Obama is demanding a much greater financial commitment from Germany and Europe to revive the economy; Mrs. Merkel and the EU are refusing, and instead urging the Americans to regulate their financial markets more rigidly.

There’s no question, Mrs. Merkel has good substantive arguments on her side. Mr. Schröder had some as well when he opposed George W. Bush before and during the Iraq war. Nevertheless, Americans and the German opposition — namely, Mrs. Merkel’s Christian Democratic Union — accused Mr. Schröder of dishonesty. After all, his antiwar views were also motivated by electoral strategy and were not entirely free of general anti-Americanism.

But come to think of it, isn’t Mrs. Merkel, too, campaigning this year? Her defiant self-assuredness in dealing with Washington may be as popular in Germany as Mr. Schröder’s antiwar stance was. The difference between the two chancellors is that Mrs. Merkel’s way of formulating her position is not aggressive, but subversive. When she defends her financial policies, she likes to remark with a wink that we shouldn’t forget where the crisis began. Everyone knows which country she means.

Mr. Obama speaks of a global crisis that demands global responses. For the Germans, this is indeed a global crisis — but one that must be resolved primarily by the U.S., since it originated there. Therefore, German finance companies that became entangled in dodgy speculations are seen as weak victims who were seduced, while the clever American seducers who caused the real-estate bubble must now be punished.

Now the victims are claiming the right to say “no” to new stimulus packages. And they are demanding that the U.S. never again be permitted to seduce — that it be constrained by “more transparency on the financial markets, which Germany called for long ago,” as Mrs. Merkel says.

Once, there were enormous hopes. With Barack Obama’s election, the trans-Atlantic rift that grew in the Bush years would finally be bridged. Now, in the financial crisis, this hope could prove an illusion. Many Germans believe they are being taken hostage by the U.S., and they want to vent their frustrations. They ask whether Mr. Obama’s gigantic stimulus programs are similar to the gigantic war programs of Mr. Bush. The new president seems to be reacting just as drastically to this “world crisis” as the Republicans did to the terrorist attacks on Sept. 11, 2001, demanding the same unconditional allegiance from allies that Mr. Bush did. Are the neo-Keynesians as mistaken today as the neoconservatives were then? Isn’t American gigantism the biggest problem?

In explaining the Americans’ motivations, Germans are reaching conclusions as unfriendly and abstruse as those in the run-up to the Iraq war (greed for oil). On March 9, the German magazine Der Spiegel published a cover story on “The Mistake of the Century — How the Failure of a Single Bank Triggered the World Crisis.” It suggested that the U.S. government purposely allowed the investment bank Lehman Brothers to fail. Why? “Germany was apparently the main goal of the speculation” of Lehman Brothers, the magazine said, “because these kinds of securities are permitted in Germany, but not in France or the United States.” And, “There is a great deal of evidence that banks targeted the funds of unwitting German retirees in trading Lehman securities.” This interpretation of events is widespread in Germany. Even the head of the Protestant church council, Bishop Wolfgang Huber, supports it.

More and more, the diffuse anger about the crisis and its consequences is erupting in social unrest; one need only look to Greece, France, Ireland, Iceland or Eastern Europe. The longer the crisis lasts, the more loudly people will point to its originator, the U.S. Mr. Obama is turning into a lightning rod for European thunder. When he travels to the old Continent for the first time as U.S. president, he most likely won’t see cheering crowds as huge as the one that greeted him last summer in front of Berlin’s Victory Column.

Before the Iraq war, George Bush succeeded in splitting Europe into the “old” and the “new.” In the financial crisis, the Continent is unified in its opposition toward his successor, Barack Obama.

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Full article and photo: http://online.wsj.com/article/SB123846238840772059.html

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It may be prickly on the outside, but the sea urchin’s spines hide — well, if not a heart of gold, at least teeth of calcite.

The urchin’s five teeth are very strong and capable of grinding limestone, creating depressions in the rock that the sea urchin can settle in. Since limestone also consists of calcite (a form of calcium carbonate), how can the teeth grind the rock without being ground down, too?

An international team of researchers has used high-resolution X-ray analytical techniques to discover the secret. The structure and composition of the tip, particularly the orientation of the calcite crystals, is exquisitely controlled, they write in The Proceedings of the National Academy of Sciences.

The teeth consist of calcite crystals (including a small amount of magnesium) in the shapes of needles and plates, and a polycrystalline calcite matrix that contains a higher concentration of magnesium. Yurong Ma, Lia Addadi and Steve Weiner of the Weizmann Institute of Science in Israel, with Pupa Gilbert of the University of Wisconsin and other colleagues, show that the magnesium levels increase toward the tip, contributing to the hardness, and that all the elements are aligned in what they call polycrystalline blocks.

The entire tooth, the researchers report, is composed of two of these blocks, which are interleaved near the tip and may create a corrugated surface that contributes to the grinding efficiency. Toolmakers might be able to learn something from the sea urchin’s approach, the researchers say.

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Full article and pĥoto: http://www.nytimes.com/2009/03/31/science/31oburchin.html?ref=science

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It takes two to duet, and one question for scientists is how these coordinated performances arise — in birds. Are they the result of cooperation, a way in which one pair signals to others that they’ve got it together? Or are they the result of conflict, evolving to avoid one partner’s song interfering with the other’s?

A study of duetting in Peruvian warbling antbirds suggests that it might be a little of both, and that context is everything. Joseph A. Tobias and Nathalie Seddon of the University of Oxford show in Current Biology that sexual conflict can cause the female of a pair that normally cooperates to “jam” the male’s song by singing over it.

The researchers exposed antbird pairs to recorded songs of other antbirds and monitored the songs the pairs produced. In one experiment, they played the songs of an intruding pair. In this case, the resident pair “both stand to lose their territory, so both should cooperate,” Dr. Tobias said. And they do. They produce a coordinated duet that in effect tells the intruders to keep away.

But when the researchers played the song of an unattached female, the pair behaved differently. “You’d expect the resident female to be highly motivated to defend her position in the partnership,” Dr. Tobias said. And that’s what occurs. The male sings its heart out, flirting with the unattached female, and the female of the pair does its best to interfere with the song by singing over it, presumably to make her mate less attractive to the other female.

“It’s clear that the male doesn’t like what she’s doing,” Dr. Tobias said. The behavior “breaks up what is otherwise a very cooperative situation into a more complicated signal,” he added.

It’s the first evidence of this kind of signal jamming among pairs, Dr. Tobias said.

And in that it leads the male to alter its song to avoid the female’s interfering notes, it shows that this kind of conflict could, over a long period, drive the evolution of coordinated song.

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Full article and photo: http://www.nytimes.com/2009/03/31/science/31objam.html?ref=science