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A survey of 200 sites in 20 countries around the world has found that bisphenol A, a synthetic compound that mimics estrogen and is linked to developmental disorders, is ubiquitous in Earth’s oceans.

Bisphenol A, or BPA, is found mostly in shatter-proof plastics and epoxy resins. Most people have trace amounts in their bodies, likely absorbed from food containers. Its hormone-mimicking properties make it a potent endocrine system disruptor.

In recent years, scientists have moved from studying BPA’s damaging effects in laboratory animals to linking it to heart disease, sterility and altered childhood development in humans. Many questions still remain about dosage effects and the full nature of those links, but in January the U.S. Food and Drug Administration announced that “recent studies provide reason for some concern about the potential effects of BPA on the brain, behavior, and prostate gland of fetuses, infants and children.”

The oceanic BPA survey, presented March 23 at an American Chemical Society meeting in San Francisco, was conducted by Nihon University chemists Katsuhiko Saido and Hideto Sato. At an ACS meeting last year, they described how soft plastic in seawater doesn’t just float or sink intact, but can break down rapidly, releasing toxins. In their new findings, they showed that BPA-containing hard plastics can break down too, and found BPA in ocean water and sand at concentrations ranging from .01 to .50 parts per million.

As for what those numbers mean for public and environmental health, it’s hard to say. BPA can cause reproductive disorders in shellfish and crustaceans, and doses below a single part per trillion can have cell-level effects, but the path from water and sand to ocean animals needs to be studied.

One disturbing possibility is that BPA could bioaccumulate, with animals eating BPA-tainted animals that have eaten BPA-tainted animals, finally reaching high concentrations in top-level ocean predators and the humans who eat them. For that to happen, BPA would have to be stored in fatty tissue, rather than passing quickly through the body.

“That’s a really difficult, unsettled question,” said Shanna Swan, a University of Rochester environmental medicine specialist who wasn’t involved in the survey.

In a 2009 Environmental Health Perspectives study of BPA concentrations in people who had recently fasted, Swan found that BPA levels remained high longer than expected. It’s possible that BPA indeed accumulated in their fat, said Swan. They could also have picked up BPA from as-yet-unappreciated non-dietary sources, such as household dust or leaching from PVC water pipes. Or both scenarios may be true.

The BPA contamination found by Saido and Sato likely comes from a mix of boat paint and plastic. About three million tons of BPA-containing plastics are produced each year. The United Nations estimates that the average square mile of ocean contains 46,000 pieces of plastic trash.

“Marine debris plastic in the ocean will certainly constitute a new global ocean contamination for long into the future,” wrote Saido and Sato in their presentation.

Giant Crack in Africa Will Create a New Ocean: A 35-mile rift in the desert of Ethiopia will likely become a new ocean eventually, researchers now confirm.

The crack, 20 feet wide in spots, opened in 2005 and some geologists believed then that it would spawn a new ocean. But that view was controversial, and the rift had not been well studied.

A new study involving an international team of scientists and reported in the journal Geophysical Research Letters finds the processes creating the rift are nearly identical to what goes on at the bottom of oceans, further indication a sea is in the region’s future.

The same rift activity is slowly parting the Red Sea, too.

Using newly gathered seismic data from 2005, researchers reconstructed the event to show the rift tore open along its entire 35-mile length in just days. Dabbahu, a volcano at the northern end of the rift, erupted first, then magma pushed up through the middle of the rift area and began “unzipping” the rift in both directions, the researchers explained in a statement today.

“We know that seafloor ridges are created by a similar intrusion of magma into a rift, but we never knew that a huge length of the ridge could break open at once like this,” said Cindy Ebinger, professor of earth and environmental sciences at the University of Rochester and co-author of the study.

The result shows that highly active volcanic boundaries along the edges of tectonic ocean plates may suddenly break apart in large sections, instead of in bits, as the leading theory held. And such sudden large-scale events on land pose a much more serious hazard to populations living near the rift than would several smaller events, Ebinger said.

“The whole point of this study is to learn whether what is happening in Ethiopia is like what is happening at the bottom of the ocean where it’s almost impossible for us to go,” says Ebinger. “We knew that if we could establish that, then Ethiopia would essentially be a unique and superb ocean-ridge laboratory for us. Because of the unprecedented cross-border collaboration behind this research, we now know that the answer is yes, it is analogous.”

The African and Arabian plates meet in the remote Afar desert of Northern Ethiopia and have been spreading apart in a rifting process — at a speed of less than 1 inch per year — for the past 30 million years. This rifting formed the 186-mile Afar depression and the Red Sea.

The thinking is that the Red Sea will eventually pour into the new sea in a million years or so.

The new ocean would connect to the Red Sea and the Gulf of Aden, an arm of the Arabian Sea between Yemen on the Arabian Peninsula and Somalia in eastern Africa.

Atalay Ayele, professor at the Addis Ababa University in Ethiopia, led the investigation, gathering seismic data with help from neighboring Eritrea and Ghebrebrhan Ogubazghi, professor at the Eritrea Institute of Technology, and from Yemen with the help of Jamal Sholan of the National Yemen Seismological Observatory Center.

www.livescience.com/environment/091102-africa-rift-ocean.html

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