destroying

Alexandria is the second largest city in Egypt and is the largest city on the Mediterranean coast. Its history goes back over 2,300 years and it was once home to a lighthouse that was among the Seven Wonders of the Ancient World and a Great Library that was the largest in the ancient world. The modern city has more than 6 million residents but still has many historic buildings and ancient monuments. But perhaps not for long.

Rising seas and intensifying storms are taking a toll on the ancient port city. For centuries, Alexandria’s historic structures have endured earthquakes, storm surges, tsunamis, and more. They are truly marvels of resilient engineering. But now, climate change is undoing in decades what took millennia for humans to create.

Over the past two decades, the number of buildings collapsing in Alexandria has risen tenfold. Buildings are collapsing from the bottom up as a rising water table weakens soil and erodes foundations. Since 2001, Alexandria has seen 290 buildings collapse. Comparing present-day satellite imagery with decades-old maps, the authors of a study by the Technical University of Munich have tracked the retreat of Alexandria’s shorelines to determine where seas have intruded into groundwater. The authors say that more than 7,000 buildings in Alexandria are at risk. They call for building sand dunes and planting trees along the coast to block encroaching seawater.

The true cost of this gradual destruction goes far beyond bricks and mortar. This is the gradual disappearance of historic coastal cities. Alexandria is a warning for such cities around the world.

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In This Storied Egyptian City, Rising Seas are Causing Buildings to Crumble

Photo, posted September 11, 2012, courtesy of Sowr via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

PFAS, short for poly and perfluoroalkyl substances, have been used in commercial products since the 1940s. There are more than 4,000 different chemicals in the class. Some of the most commonly used PFAS chemicals, like PFOS and PFOA, have long half-lives, which has earned them the moniker “forever chemicals.”

These dangerous chemicals have not been manufactured in the U.S. since the early 2000s, but they can still be found in various imported goods. PFAS chemicals have been linked to cancer, birth defects, thyroid disease, and liver damage. These forever chemicals linger in the environment and scientists have found them in the blood of virtually all Americans.

Researchers at Rice University have recently discovered an efficient catalyst for destroying PFAS forever chemicals. Unexpectedly, the catalyst was actually in the control group in a study they were performing.

The study, published in the journal Environmental Science and Technology Letters, found that boron nitride, acting as a light-activated catalyst, destroyed PFOA at a faster clip than any previously reported photocatalyst.

The catalyst, boron nitride powder, is a commercially available synthetic mineral that is widely used in makeup, skincare products, thermal pastes for cooling computer chips, and various other industrial products. The discovery began with dozens of failed experiments on a variety of more promising PFAS catalysts. But along the way, they found that the boron nitride control material repeatedly yielded positive results.

The research has already attracted the attention of industrial partners seeking to develop off-grid water treatment systems that both protect human lives and support sustainable economic development.

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Boron nitride destroys PFAS ‘forever’ chemicals PFOA, GenX

Photo, posted April 9, 2009, courtesy of Rex Roof via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rising seas are destroying buildings

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Destroying Forever Chemicals | Earth Wise

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