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Ozone layer deal may have led to new contaminant problem – CBC.ca

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A landmark environmental agreement that helped close the ozone hole in the 1990s has led to new chemical contaminants forming in the atmosphere and accumulating on land.

“The Montreal Protocol was probably one of the best regulations out there to involve all the countries at once,” said Heidi Pickard, one of nine researchers to publish the findings in a paper Thursday.

“But, of course, you have these unintended consequences.”

The Montreal Protocol, which came into force in 1989, banned chlorofluorocarbons, or CFCs, that were used in refrigerators, air conditioners and aerosol sprays. They were destroying the ozone layer, which helps protect the planet from damaging ultraviolet solar radiation.

It has been signed by 197 parties and is considered the world’s most successful environmental agreement.

Rows of air conditioners are seen on the walls of a building in Singapore’s financial district December 11, 2009. The Montreal Protocol, which came into force in 1989, banned chlorofluorocarbons, or CFCs, that were used in refrigerators, air conditioners and aerosol sprays. (Vivek Prakash/Reuters)

But the chemicals used to replace the banned ones are breaking down in the atmosphere into new contaminants known as short-chain fluorinated alkyl acids.

They don’t seem to be as toxic as other long-lived contaminants such as dioxins. They are, however, highly persistent, said co-author Amila De Silva of Environment Canada.

“They’re known as forever chemicals. They just don’t break down.”

Little is known about this family of chemicals, said Pickard, who now works at Harvard University. But at least one of them is known to be toxic to plants. Others harm freshwater insects. Others accumulate in plants, including food crops.

High accumulation rate

Their presence is growing. Although still measured in billionths of a gram per litre, their concentration in ice cores from two High Arctic locations has increased about sevenfold since 1990, said co-author Alison Criscitiello from the University of Alberta.

“It’s significant,” she said. “The accumulation rate is fairly high.”

A giant glacier is seen making its way to the waters of Croaker Bay on Devon Island Friday, July 11, 2008. Short-chain fluorinated alkyl acids have been found contaminating two of Earth’s remotest places — the Devon Island ice cap and Mt. Oxford on Ellesmere Island. (Jonathan Hayward/Canadian Press)

Concentrations of one chemical known to be harmful are expected to increase as further substitutes for the banned compounds are phased in.

As well, preliminary data suggests the concentration of these chemicals is higher in the south.

“When we measure rain and snow in populated urban areas, we’re finding quite a prevalence of these substances in much higher concentration,” De Silva said.

Finding these acids in two of Earth’s remotest places — the Devon Island ice cap and Mt. Oxford on Ellesmere Island — should be a warning, the scientists say. More needs to be known about them, and soon.

“There is not toxicological information out there,” Pickard said.

No one knows, for instance, if they increase in concentrations higher up the food chain.

“The lower end of the food web is probably the target for these substances — the invertebrates, the plankton, plants that take up water,” De Silva said.

Pickard said some scientists believe the chemicals have immune-system impacts on children at levels already exceeded in the ice cores.

“There’s a lot of research that needs to be done,” said Criscitiello. “It’s quite a large class of chemicals.”

The researchers hope their paper in Geophysical Research Letters will spark interest. And, if nothing else, they hope their findings highlight a need to cast a wide scientific net when environmental regulations are drafted.

“When the Montreal Protocol came into effect, there wasn’t enough research available to understand (the consequences),” said De Silva. “A more holistic approach to decision-making when it comes to environmental impacts is necessary.

“It’s difficult to do, but it is necessary.”

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Crew Dragon with two NASA astronauts docks to ISS – TASS

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NEW YORK, May 31. /TASS/. The Crew Dragon spacecraft with Doug Hurley and Bob Behnken on board has successfully docked to the International Space Station (ISS), as follows from a NASA broadcast on Sunday.

The spacecraft began approaching the ISS about two hours before docking than was carried out 10:16 ahead of the schedule. The Crew Dragon spacecraft was launched using the SpaceX Falcon 9 rocket at 22.22 pm Moscow time on May 30 from the Cape Canaveral, Florida.

Crew Dragon is a configuration of the cargo spacecraft Dragon, which had already delivered cargoes to the ISS. A Falcon-9 rocket put the cargo vehicle in space on March 2. Its docking with the ISS was carried out automatically the next day.

NASA stopped crewed flights in 2011 after the Space Shuttle program came to an end. From that moment on all astronauts were delivered to the ISS and back by Russia’s Soyuz spacecraft. Originally the Untied States was to start using commercial spacecraft for crewed missions in 2017.

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Toddler could be battling rare syndrome in response to COVID-19 – Winnipeg Free Press

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More than a month after testing positive for COVID-19, a Winnipeg toddler is fighting another illness – a possible rare inflammatory syndrome that could be part of the body’s reaction to new viruses.

The girl’s mother told CBC News doctors are trying to find out whether the one-year-old has developed Kawasaki disease, or multi-system inflammatory syndrome in children, now that she is negative for COVID-19 but is still seriously ill.

To read more of this story first reported by CBC News, click here.

The Winnipeg Free Press and CBC Manitoba recognize each other as trusted news sources. This content is made available to our readers as part of an agreement to collaborate to better serve our community. Any questions about CBC content should be directed to: talkback@cbc.ca

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A full Strawberry Moon illuminates Weyburn's sky – Weyburn Review

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June’s full moon, which is the last full moon of spring or the first of summer, is traditionally called the Strawberry Moon.

This full moon brings with it a penumbral eclipse, which occurs when the moon crosses through the faint outer edge of Earth’s shadow (the penumbra), making part of the moon appear slightly darker than usual. Unlike a full lunar or solar eclipse, the visual effect of a penumbral eclipse is usually so minimal that it can be difficult to see.

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This eclipse was only visible from parts of Australia, Asia, Africa, Europe, and South America, but not from North America.

The tradition of naming moons is rich in history. According to the Old Farmer’s Almanac, the name, Strawberry moon, originated with Algonquin tribes in eastern North America who knew it as a signal to gather the ripening fruit of wild strawberries.

Other names for this moon include the Honey Moon and the Mead Moon. It has also been called the Rose Moon, as many roses begin blooming in June.

Historically, full moon names were used to track the seasons and, for this reason, often relate closely to nature. The moon names used today come from Native American and Colonial-era sources. Traditionally, each full moon name was applied to the entire lunar month in which it occurred, rather than just the full moon itself.

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