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Photo: Rory Carroll/The Guardian.
Aoibheann Boyle and Andrew Collins inspect oysters at the Green Ocean Foundation’s project in Dún Laoghaire harbor. 

I don’t have a traditional Irish story to offer for St Patrick’s Day, but today’s article may get you singing about sweet Molly Malone and her “cockles and mussels, a-live, a-live-o.”

That’s because Ireland is doing some interesting work with shellfish. Rory Carroll of the Guardian reports from Dublin’s Fair City about an oyster graveyard rising from the dead.

He begins, “The dinghy slowed to a stop at a long line of black bobbing baskets and David Lawlor reached out to inspect the first one. Inside lay 60 oysters, all with their shells closed, shielding the life within. ‘They look great,’ beamed Lawlor. So did their neighbors in the next basket and the ones after that, all down the line of 300 baskets, totaling 18,000 oysters.

“They are, however, never to be eaten. Instead they are tasked with reproducing and restoring oyster reefs to Dublin Bay more than two centuries after they were wiped out. …

“Similar restoration projects are unfolding elsewhere in a continent that once had sprawling reefs of the European flat oyster (Ostrea edulis) until overfishing, dredging and pollution wreaked obliteration.

Reefs create rich ecosystems, provide a habitat for almost 200 fish and crustacean species and play a vital role in stabilizing shorelines, nutrient cycling and water filtration.

“ ‘These oysters are amazing climate heroes,’ said Lawlor, co-founder of Green Ocean Foundation, a nonprofit that is driving efforts in Dublin. ‘They are natural filter feeders. Each oyster filters at a rate of 190 liters [~200 quarts] of seawater a day.’

“By feeding on plankton and nitrates, the oysters clear algae and help sunlight to reach the seafloor, boosting sea grass – a carbon sink – which in turns helps other species and improves coastal biodiversity and marine habitat.

Ireland’s inhabitants cultivated oysters in the middle ages but in the 1800s industrialization and overfishing killed off the Dublin Bay reefs – a phenomenon replicated from Scandinavia to the Mediterranean.

“Inspired in part by New York’s Billion Oyster Project [see my blog post here] Lawlor enlisted volunteers and business sponsors for pilot projects that moved oysters from Tralee Bay in County Kerry to sites in Malahide, Howth, Poolbeg and Dún Laoghaire, which ring Dublin bay, and in Greystones, in County Wicklow.

” ‘You’re building your understanding of why things work well or don’t work well. You want to make sure they survived, to see what the growth was like, and to see if they spawn,’ said Lawlor. The transplanted oysters fared especially well in Dún Laoghaire so it was chosen for the next phase of the project. …

“Scientists from Dublin City University’s Water Institute analyzed the water last year for baseline indicators and will monitor the oysters’ impact with sensors and chemical and biological assessment.

“The baskets are connected along a 100-metre line and are flipped by hand every few weeks to let Arctic terns, gulls and other birds peck away fouling that might otherwise curb the flow of water through the baskets.

“In Northern Ireland, the charity Ulster Wildlife used a different technique recently to place 2,000 adult oysters and 30,000 juveniles, sourced from Scotland, on the Belfast Lough seabed.

“The Luna Oyster Project, a collaboration between Norfolk Seaweed and Oyster Heaven, aims to restore 4 million oysters to the North Sea by using the first mass deployment of clay structures called mother reef bricks.

“The Dublin initiative is far smaller but will hopefully grow, said Lawlor. ‘The temptation is to think massive but you need to take one step at a time. A lot of the challenge is bringing people with you,’ he said, citing government departments, local councils, wildlife groups and harbor authorities.”

More at the Guardian, here.

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Photo: John and Suzanne’s Mom.
Do we know what’s in our drinking water? University of British Columbia researchers are working on an experimental material to remove toxic “forever chemicals” from water. 

As soon as we learn about a new hazard to humans, it seems, science labs pop up to address it. Lately, we’ve been hearing a lot about “forever chemicals,” dangerous compounds that are often in drinking water. Thank goodness, a variety of labs are on the case.

For example, as Allyson Chiu reports at the Washington Post, Canadian researchers “have developed a method to filter toxic ‘forever chemicals’ from water and potentially destroy the long-lasting compounds permanently.

“Commonly known as ‘forever chemicals’ because they can persist in the environment for years, these hazardous compounds have long troubled environmentalists and regulators. Their harmful effects on human health are well documented, but their ubiquitous use and the challenges in breaking them down have complicated efforts to eliminate them.

“Pressure to do so is growing. In March, the Environmental Protection Agency proposed the nation’s first drinking-water standards requiring water utilities to reduce levels of PFAS — perfluoroalkyl and polyfluoroalkyl substances.

The new technology, described by one of its developers as a ‘Brita filter, but a thousand times better,’ could help address the problem, experts say.

“ ‘The potential impact will be huge,’ said Madjid Mohseni, a professor of chemical and biological engineering at the University of British Columbia who led the research. …

“Polyfluoroalkyl and perfluoroalkyl substances are a class of thousands of different chemicals with varying properties. The highly durable chemicals have been used for decades to make nonstick cookware, moisture-repellent fabrics and flame-retardant equipment, and they are found in other commonly used consumer goods such as cosmetics and food packaging.

“Several U.S. states and other countries have banned certain types of PFAS, and many major companies say they have discontinued their use, but the compounds have shown up in the water supplies of communities across the country and the world. The chemicals have been linked to infertility, thyroid problems and several types of cancer.

“Technologies already exist to remove PFAS from water, but Mohseni and other experts say these approaches have limitations.

“Activated carbon, for example, can filter what is known as long-chain PFAS but does not as effectively trap the shorter-chain variants of the chemicals. Short-chain PFAS, some of which can be toxic at low doses, are becoming more prevalent as many manufacturers use them as a replacement for the long-chain compounds.

“Existing methods also typically create waste products that contain high concentrations of PFAS, which often end up in landfills or are incinerated, said Erik Olson, a senior strategic director at the Natural Resources Defense Council.

“From landfills, the harmful chemicals could leech back into the environment. Burning them is not ideal, either. ‘Only extremely high-temperature incineration can even start to destroy PFAS,’ Olson said. ‘Normal incineration just simply sends PFAS up the smokestack.’

“Mohseni said the material his team developed — which looks like tiny porous plastic beads — can remove long- and short-chain chemicals at rates that match or exceed industry standards. The PFAS it captures could be stripped away, also making the beads potentially reusable or recyclable, he said.

“Additionally, Mohseni said, the team engineered techniques designed to break the leftover PFAS down into harmless compounds.

“The beads eventually could be used in products to filter water in homes, industrial sites and at municipal levels, he added. However, for in-home applications, users would have to send the used filters to centralized locations for regeneration or recycling, and for the PFAS to be broken down fully — somewhat like how some used coffee pods are sent back to manufacturers for recycling, Mohseni said.

“His team’s findings have been published in several peer-reviewed journals.

“Although the technology is promising, experts not involved in the research say it has yet to be proved in real-world settings at scale. The UBC research team has launched pilot trials in British Columbia, but none of the sites are yet sources of drinking water. …

“Removing the chemicals from water and breaking them down is only part of the solution to the PFAS problem, said Cora Young, an associate professor of chemistry at York University in Toronto who studies the chemicals.

“ ‘Destroying PFAS that already exist is a useful thing, but a lot of other approaches have to be used to actually reduce its impact as an environmental problem,’ Young said.”

More at the Post, here. Good on you, Canada!

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