USA banning copper-based antifouling

[JumbleDuck]

On the other hand, metals and complex chain compounds tend to hang around longer and do nastier things.

Yes, and I don't know anything about the dynamics of copper in seawater, though I probably have colleagues who do. I have found a paper (http://plymsea.ac.uk/764/1/The_copper_content_of_sea-water.pdf) saying that seawater contains about 10mg of Cu per cubic metre, so the 1kg or so of copper (in oxide) which I paint on each spring is 100,000 cubic metres' worth. That sound like quite a lot, but Kames Bay contains (scribbles on back envelope) about 60,000,000 cubic metres of seawater so there is already about 3/4 ton of copper sloshing around in it.

 

[NormanS]

See also, tanker spills. Drop a few thousand tonnes of oil in the deep blue and wave action will quite soon return it to carbon molecules. Spread it over a sensitive shorefront and you get lots of dead things with big eyes that play badly in the media. But even there, nature will take its course and clean it up. Biggest f'up was steam cleaning the beaches in Alaska post Exxon Valdex, which stripped them of all life for years.

On the other hand, metals and complex chain compounds tend to hang around longer and do nastier things.

I'm sure you realise that the steam cleaning of a few small patches of shoreline in Prince William Sound, was purely a PR exercise, and would have negligible effect on the environment. Exxon had to be seen to be doing something. The world's media had to be fed.

 

[Hydrozoan]

Yes, and I don't know anything about the dynamics of copper in seawater, though I probably have colleagues who do. I have found a paper (http://plymsea.ac.uk/764/1/The_copper_content_of_sea-water.pdf) saying that seawater contains about 10mg of Cu per cubic metre, so the 1kg or so of copper (in oxide) which I paint on each spring is 100,000 cubic metres' worth. That sound like quite a lot, but Kames Bay contains (scribbles on back envelope) about 60,000,000 cubic metres of seawater so there is already about 3/4 ton of copper sloshing around in it.

No disrespect to the late Dr W R G Atkins, but you could have found something a bit more recent than 1932! Not only the analytical methodology, but also techniques to avoid contamination during sampling, have come on a lot since then – and we have vastly more data on trace metal concentrations in seawater, and from a far wider range of locations.

Your 10mg/m3 is 10ug/l, which is high for dissolved copper (the fraction of toxicological concern in water) in most UK coastal waters. The medians for most areas of England and Wales are about 1-2 ug/l (estuaries) and about 0.5-1 ug/l (coasts) - see e.g. Tables 5.3 and 5.4 (pp 37, 38) at https://www.wfduk.org/sites/default/files/Media/Copper saltwater - UKTAG.pdf

So you are likely overestimating the background of ‘natural’ dissolved copper by perhaps 10x or so – in which case your 750 kg in Kames Bay might be nearer 75kg.

BTW that report proposed a UK Environmental Quality Standard (EQS) to protect marine life, but the actual value finally adopted (link to spreadsheet at https://www.gov.uk/guidance/surface-water-pollution-risk-assessment-for-your-environmental-permit) is 3.76 ug/l dissolved Cu where the Dissolved Organic Carbon level is ≤ 1 mg/l – and higher where the DOC is greater, as complexing of the copper by DOC tends to reduce its toxicity. I have given links to equivalent US marine copper criteria here http://www.ybw.com/forums/showthrea...he-greatest-hazard-to-the-worlds-oceans/page2.

 

[JumbleDuck]

No disrespect to the late Dr W R G Atkins, but you could have found something a bit more recent than 1932!

I did wonder about that, but since it came from a current university website I thought it might still be valid. My doctoral thesis contained references from the 1910s and my masters thesis (in contact stress analysis) had a genuinely relevant reference from the fifteenth century!

So you are likely overestimating the background of ‘natural’ dissolved copper by perhaps 10x or so – in which case your 750 kg in Kames Bay might be nearer 75kg.

Thanks. A tonne of the stuff did seem a bit high!

 

[Hydrozoan]

I did wonder about that, but since it came from a current university website I thought it might still be valid. My doctoral thesis contained references from the 1910s and my masters thesis (in contact stress analysis) had a genuinely relevant reference from the fifteenth century!

Thanks. A tonne of the stuff did seem a bit high!

Determining heavy metals in seawater (especially at their lowest levels in ocean waters) presented huge difficulties for many, many decades. ISTR one eminent marine chemist writing ruefully (in the ‘70s I suspect, and with excusable exaggeration) that the history of studying heavy metals in the oceans to that time had been largely the history of studying (sample) contamination without realising it!

Of course early studies may still have validity and as I said, I wasn’t knocking the seminal work at Plymouth. I haven’t read the paper in detail and the 10ug/l may have been accurate for the samples in question but it isn’t representative of UK waters. Greater efficiency of analysis, and the increase in resources devoted to it, means that geographical and temporal coverage is now vastly better too. But of course advances in toxicity testing have, over a similar period, greatly decreased the ‘levels of concern’.

Thanks BTW for your persistence earlier in the thread on the discussion of leaching rates, which was interesting. I am sorry to have repaid it by so greatly increasing your perception of the significance of your own 1kg/pa contribution!

 

[JumbleDuck]

Of course early studies may still have validity and as I said, I wasn’t knocking the seminal work at Plymouth. I haven’t read the paper in detail and the 10ug/l may have been accurate for the samples in question but it isn’t representative of UK waters.

Is there non-dissolved copper in the sea as well. in plankton, for example? Bet you can guess I am not a marine biologist ...

Thanks BTW for your persistence earlier in the thread on the discussion of leaching rates, which was interesting. I am sorry to have repaid it by so greatly increasing your perception of the significance of your own 1kg/pa contribution!

No apology necessary. I never, ever mind having my mistakes corrected, though of course it is nice when it's done tactfully, as you did.

 

[Hydrozoan]

Is there non-dissolved copper in the sea as well. in plankton, for example? ...

Yes, very much so. Of the first row transition metals, Cu is typically the most strongly complexed and adsorbed (look up ‘Irving-Williams series’), so in estuarine and coastal waters the bigger part of the total Cu will typically be adsorbed on suspended particles – e.g. on clay minerals, iron and manganese oxides, humic substances - and some will indeed also be present in plankton.

 

[JumbleDuck]

Yes, very much so. Of the first row transition metals, Cu is typically the most strongly complexed and adsorbed (look up ‘Irving-Williams series’), so in estuarine and coastal waters the bigger part of the total Cu will typically be adsorbed on suspended particles – e.g. on clay minerals, iron and manganese oxides, humic substances - and some will indeed also be present in plankton.

Ah-ha. Perhaps that explains the good doctor's historical results.

 

[Hydrozoan]

Ah-ha. Perhaps that explains the good doctor's historical results.

Oh all right: I’ve now read the whole paper – much of it several times, scratching my head!

Yes, it seems that Dr Atkins did not filter his 1932 sample, but the two concentration techniques used – evaporation (?) and electrochemical deposition – might not have recovered much of the particulate Cu anyway. Especially as he appears not to have acidified the sample – a modern practice to prevent loss of Cu by adsorption on the container, which also tends to recover it from particulates if samples are unfiltered. At least the result of ca. 10ug/l was obtained by two methods, credible in principle, applied to one surface sample taken (mercifully) by wooden bucket.

For regarding his sample of 1921 (200ug/l Cu, reported by the Government Chemist in 1924) it must have been an ‘Ah!’ or ‘Duh!’ moment when L H N Cooper later pointed out that the sampling bottle (a metal Nansen bottle, I imagine) had internal gunmetal bolts with visible verdigris!

Dr Atkins’ comment that samples taken with it would contain ‘traces of added copper’ is to us a spectacular understatement. But he had relatively little idea of what to expect and no other means to get a sample from depth. And it is not even clear that the sample was ever intended for Cu determination: it may have been used by chance in an investigation of oyster mortality/greening.

You have fortuitously brought up from time’s depths a fascinating account of some of the earliest attempts to determine Cu in seawater. But more than enough chemistry: do join me in raising a glass to the ‘good doctor’ – stuck in Falmouth Harbour in 1921, awaiting a weather change to start his cruise.

 

[Blue Sunray]

You credit the bbc with supplying facts?

https://www.forbes.com/sites/realsp...ion-is-now-the-biggest-polluter/#4bc079f61a19

states:

"In fact, one huge ship produces the same amount of cancer-causing chemicals as 50 million cars."

Most people know that once out of site of land these ships switch over to burning the most unrefined oil possible.

wikipedia:
Emissions from ships have a much more significant environmental impacts; many ships go internationally from port to port and are not seen for weeks, contributing to air and water pollution on its voyage.

Transport mean Passengers Emissions
(g CO2/km*pax)
Small car 4 42

Big car 4 55

Ship – 245

Yes, rather more than Wikipedia, try listening to the programme before flaunting your ignorance.

 

[Seven Spades]

As I asked before, if coppercoat is non-eroding, why does it need replaced after ten years?

Because owners abrade it in the car park to "freshen it up" and after 10 years they have rubbed it off it is not wearing away in the water.

 

[Brent Swain]

It looks like the USA is likely to roll-out a ban on anything containing copper. It's starting in Washinton state in January, and I expect we'll see it happen across the USA and caribbean over the next few years.

Interestingly, it's not just a ban on supplying and applying the stuff, they're also banning any recreational boat under 65ft with copper on their hull from entering their ports.

This was on Boating Business News

"In 2011, Washington became the first state to adopt a no-copper paint rule. And from January 1 2018, no new recreational boat up to 65ft can arrive with copper on its hull and no copper can be sold or applied to a boat after January 1 2020."

So, anyone thinking of taking their boat that side of the atlantic, would be wise not to spend out on coppercoat.

They found that about 80% of copper in the ocean there, comes from vehicle brake shoes. The suggestion is, that boats over 65 feet don't shed their copper paint!
I avoid the US like the plague. No reason for anyone to go there. European tourism there has dropped 40% in recent years .Closest I came, in my last voyage, was thru the Hawaiian islands, skipping them completely.

 

[PetiteFleur]

EU 45 antifouling contains, would you believe, 45% copper oxide, which they claim is the highest available.

Yes - and it's rubbish! It may have a lot of copper but I tried it about 3 years ago and I had the worst fouling I've ever seen. On the East Coast on the River Deben

 

[greeny]

Would it not be true to say that a boat using Coppercoat, usually 4 layers, which lasts 10 yrs plus will have a much lower release of copper into the environment through erosion and annual buffing, than an equivalent sized boat which is being pressure washed and conventionally antifouled every year?
If this is the case, then any legislation change should consider this fact and make Coppercoat the preferred solution to boat fouling coatings.
I may be wrong but I also think big ships use much stronger anti fouls and and many times more quantity than leisure craft throughout the world. Just because the pollution is coming from a commercial vessel doesn't make it right and should not exclude it from scrutiny.

 

[vyv_cox]

I may be wrong but I also think big ships use much stronger anti fouls and and many times more quantity than leisure craft throughout the world. Just because the pollution is coming from a commercial vessel doesn't make it right and should not exclude it from scrutiny.

I don't think this is correct. I tried to research it a few months ago but didn't get very far. The words 'nanotechnology' seemed to come up quite frequently but the composition was about the same as we are used to. They use far more of it of course but when the problems with TBT first became apparent it was clearly the boats berthed in shallow water around the coast that were the main culprits compared with ships on ocean passage. Banned for all now of course.

 

[thinwater]

There seems to be some exaggeration in this thread.


New Bill and More Research
On March 15, Washington’s governor signed a bill that delayed all phases of the ban until January 1, 2021.

The legislation approved in 2011 banned the sale and use of copper antifouling paint that contains more than 0.5 percent copper. The first phase of the ban was set to go into effect January 1, 2018, and stipulated new recreational boats (up to 65 feet) may not be sold with copper-based antifouling paints. The second phase banned the sale of copper-based antifouling paints for recreational boats and prohibited the application of copper-based paints to boats beginning January 1, 2020. The ban did not apply to recreational boats greater than 65 feet or commercial boats. Washington state was the first state to adopt anti-copper paint guidelines in an effort to protect water quality.

As for the rest of the USA, it's basically quiet.

The change is not Trump-related, but is actually the regulators looking at the questions more closely in a state where Trump holds no sway.

 

[Hydrozoan]

Would it not be true to say that a boat using Coppercoat, usually 4 layers, which lasts 10 yrs plus will have a much lower release of copper into the environment through erosion and annual buffing, than an equivalent sized boat which is being pressure washed and conventionally antifouled every year? ...

Take a look at AntarcticPilot's #56 above.