Silver nanoparticles are not harmful to fish

New research suggests Silver nanoparticles are not harmful to fish:

Nanosilver kills the microbes that produce nasty smells and it is now widely used in t-shirts, socks and many types of sports clothes. But when these high-tech outfits go in the washing machine, the nanosilver is washed out and ends up in our rivers.

So a team led by Charles Tyler at the University of Exeter have done some research to see what that means to fish, which are usually rather sensitive to silver...

Working with rainbow trout, the team exposed the fish to water enriched with different sizes of nanosilver. The idea was to see if the silver would find its way into the trout and where the tiny particles were more likely to accumulate.

After ten days of exposure Tyler and the team analysed the fish, looking for damage to the cells or to the genes that control essential cell processes.

What they discovered is good news: 'Despite much recent concern around nanoparticle pollution, we found that the fish took up nanosilver in only very small amounts,' says Tyler.

That's encouraging. But note the caveats...

Tyler and his team had the particles they used carefully characterised: 'we knew exactly what we were exposing our fish to,' he says. Other studies exposing fish to slightly different nanosilver particles might yield different results.

Nanoparticles are going to be so useful you can see why industry and scientists can't resist them. But nanoparticle toxicity is still barely understood.

This story came from Planet Earth Online - produced by the Natural Environment Research Council.

Katherine Swinfen Eady, my favourite landscape artist

Here's a lovely image from my favourite landscape artist. It's the Salisbury Plain - Katherine captures the feeling of it so well. It instantly takes me back to when we used to live there and roam across it with Muttley the dog.

Katherine has an exhibition on at the moment - at the Wren Gallery, Burford, Oxon. But you can also see more of her lovely pictures at this link: Katherine Swinfen Eady - landscape artist.

Brown Galingale, Cyperus fuscus - a Red Data Book weed in a suburban garden

My parent's garden is an untidy, tiny 'un-cultivated' (but not un-cared-for) fragment of suburban Sussex. Yet it harbours some lovely rarities. There are orchids on the lawn - carefully mown around since Barrie spotted their tell-tale leaves amidst the grass. Poisonous Thorn apples are tolerated in the borders. And now he's found a Red Data Book species growing as a weed...

I showed a sedgy thing which grew in a Yoghurt pot of parsley in the greenhouse to a botanist at a Woods Mill meeting, and she has said: "Your plant is Brown Galingale - Cyperus fuscus, which I've never seen before, so am delighted to have met it at last. Apparently now known in the UK as a native only from Surrey, Somerset, Hants and Jersey and RDB Vulnerable. Did you say it was in your garden? - I wonder how it got there?"
Always knew my garden was special. Red Data Book listed. Cor!

It's amazing what turns up and thrives if you let it.

First evidence of warming-related methane releases from the Arctic Sea

I've been editing some science stories for the UK's Natural Environment Research Council. This one is on the powerful climate gas methane, seeping from deep water stores in a warming Arctic Sea. It's worrying, if uncertain, news.

First evidence of warming-related methane releases from the Arctic Sea.: "Plumes of the powerful greenhouse gas methane, spotted rising from the seafloor off Spitsbergen, may be early signs of 'positive feedback' in climate change, where warming accelerates further change."

Scientists surveying the Arctic seabed, to estimate how much of the potent greenhouse gas methane might be released by climate warming, have found evidence that the process may already have started.

The team, including researchers from Birmingham University, the National Oceanography Centre, Southampton, and Royal Holloway University, London, found more than 250 plumes of methane bubbles rising from the seafloor off Spitsbergen. This is the first time scientists have found evidence suggesting such seeps are due to ocean warming...

But it's not the only bit of the puzzle. I'm working on another story that talks about a 'negative feedback' effect caused by retreating ice in the Antarctic opening up sea where new marine communities flourish. (More on that later).

Sadly, the two don't balance each other out. Climate science is complicated, yet the overwhelming evidence is that most of the 'feedback' effects on climate change accelerate rather than hold it back.

Birds benefit from agri-environment schemes

Birds benefit from agri-environment schemes: "Twenty years of agri-environment schemes designed to protect biodiversity from intensive farming have succeeded in boosting bird species and population, according to a survey of Peak District farms."

Some good news for wildlife and farming, though I still feel the tide is running the wrong way...

24 hours of global air traffic.

If you've ever wondered whether your flight was really likely to be affecting climate change, take a look at this YouTube clip of 24 hours of flights around the world compressed into a minute or so...

Watching the pattern of light moving across the globe is pretty interesting too.

British timber, British woodlands

Do you buy FSC wood? We usually do for our business and home because of it's environmental credentials. But now I've found out that we might well be doing more good buying British wood. That's because almost all the woodland in the UK is pretty much sustainably managed (give or take a few cowboys). You can't legally fell more than 5 cubic metres of wood in any calendar quarter without a licence from the Forestry Commission, even if it's on your own land. And they don't usually give a licence with insisting that you restock the area, and keep it restocked for at least 10 years. (Here's a summary of the rules, if you're interested.)

So when you compare that with the environmental cost of shipping timber in from overseas, or the unknowns of non-certified timber, buying British looks like the responsible action.

And it can really help UK conservation. Here in Devon, we've found a really local source of timber - a 55 year old plantation that is being felled to reveal and regenerate the original oak woodland it covers. More about that on our Wheatland Farm blog, but here are a couple of pictures. It's going from this...











to this...














Some interesting snippets:

• Apparently, South Africa has certified all of it's timber as FSC approved


• The UK hasn't done very well with woodland conservation in the past. Thousands of years ago most of Britan would have been forested, but as long as 1,000 years ago coverage had fallen to about 15%. And by 1900 we reached a low point of 5%. Since then things have got a little better, with about 8% of land cover wooded by 2000.


• And here's an alarming thought. By the time you make a wooden floor, about 75% of the wood will have gone to waste...