Shell fish in August.... Myth and reason?

[Siggers]

Hi,

Having worked in Marine research and used Mussels as one of our pollution indicators, they certainly absorb all sorts of stuff, however we've eaten Mussels through the summer months for years with no adverse effects.

I would always suggest to apply common sense with any foraging and this can be applied to coastal areas. Do ask the local fishermen - they will help and look around at the costal environment. Sewer outfalls do have tell tail signs.

We've also found that if there is a real problem in the area, then the local authorities will put up signs in prominent places to warn of the taking of shellfish.

Simply - Be sensible and Safe and Enjoy!!!

Paul

 

[trixx]

It really does come down to common sense. Yes, human waste is much more of a potential problem than algal blooms, so avoid picking mussels from harbours, near sewage outfalls, areas where the tidal flow is slack, or in general anywhere that pollutants or waste may be a problem. Siggers is correct, on the rare occasions there is a potential problem the local authorities are not slow to advertise the fact.

On the subject of "R" in the month, I will borrow some wisdom from a learned French friend:

The "R" months thing comes from the oyster reproduction cycle: In May/June they are "fat" with the milky gonad milk; it takes a lot of energy to produce so in July/August they are virtually emaciated. Add to that the challenges to bring them fresh to Paris until the 70s.

 

[pango]

The various toxins in filter-feeding shellfish as a direct result of algael blooms and their potentially lethal consequences are no myth, but scientifically proven fact! The monitoring of seafood products isn't done simply to keep people in a job or to give the industry a hard time, but is done because of a very real concern for public health and safety.

Our coastline is probably cleaner now than it has been for a couple of hundred years, at least. If you can imagine every British village, town and city ulimately discharging its sewage into our seas from the time of the Industrial Revolution until relatively recently, then it wouldn't surprise me to discover that the rhyme we all know originated in the same era. Imagine the filth that must have been washing out of the Thames, or the Clyde, and the stench in summer months!

However, cyanobacteria are natural phenomenon, and as our earliest ancestors travelled mainly around coastlines, probably exploiting abundant coastal food supplies, they would most certainly have amassed an immense amount of knowledge with regard to what was and was not good to eat. They would certainly have been aware of something with the potential to eradicate an entire family unit!

Either follow the official monitoring services or follow the rhyme! Your only other option is chuck and chance it, which I've done on numerous occasions.

Cheers.

 

[trixx]

potentially lethal consequences are no myth, but scientifically proven fact!

No argument about that, but keep it in perspective - the risk is vanishingly small. The last reported case of PSP in the UK was in 1968, over 40 years ago, and that wasn't fatal. It is much less prevalent than botulism, another extremely rare but potentially fatal disease. (There have been a handful of botulism cases in the UK over the last few years)

So the chances of contracting botulism in the UK any given year are about 1 in 60 million, and the chances of contracting PSP are 1/40th of that. Approximately. To put it another way, in the UK you are statistically more likely to die due to an aeroplane crashing on your head than from shellfish poisoning.

Or, if you prefer, it's like playing Russian Roulette using a pistol with one bullet but 2 billion chambers. Consequences potentially very nasty, but extremely unlikely.

We're really only talking about mussels here, too, as they are most likely to concentrate any toxins. Other shellfish carries an even smaller vanishingly vanishingly tiny bijou micro-riskette. Certainly not enough to worry a big hairy bushcrafter. Although if anyone is still inclined to think the sky is falling, then have a look at the Scottish NHS guidance notes on the subject - the first part details the theoretical dangers and the medical symptoms, but if you can make it through that without wetting yourself the second part details the EU and UK-wide monitoring policies and should give you a nice warm comfortable feeling.

If anyone's interested in the scientific view, here's an article that includes some references worth reading.

As I said, if there are ever any likely problems the Local Authority will shout it from the rooftops, and in the absence of any specific warnings simply use common sense when gathering mussels.

 

[Jolyon]

Thanks All,

I would say that the oyster spawning is where the saying comes from, (i know of no rhyme) as I mentioned in my origanal thread the saying I thuoght only linked to Oysters (that where eaten like candy by the working class in the Thames estury during the times when it was an open sewer).

The Idea that the saying comes from our ancient ancestors does not wash...... unless they used the modern calander?......

 

[gregorach]

So I stand by my previous statement, it's an absolute myth that shellfish shouldn't be eaten in the summer months. How do I know? I'm a commercial shellfish fisherman and I haven't noticed my customers dropping dead, so I'd suggest that my practical experience trumps your googling in this instance.

Fair enough mate. I stand corrected.

 

[trixx]

Fair enough mate. I stand corrected.

No worries Duncan.

 

[pango]

Duncan, you're not wrong mate. I live on the Fife coast, which has had a couple of alerts in the last 10 years.

As Trixx says, the risk is infinitesimal, but the fact that far fewer people forage the coast than in our parents and grandparents days is also hugely contributory.
The vast majority of seafood is bought in restaurants and supermarkets, and so is scrutinised.

 

[Hoodoo]

There are four kinds of poisoning you can get from shellfish (paralytic, neurotoxic, diarrheal, and amnesic), all of which are caused by toxins produced by algae or cyanobacteria during the summer months, which are then concentrated by filter feeders such as bivalves. Two of them (paralytic and amnesic) are potentially deadly. The Scottish Marine Research Laboratory (and, I presume, whichever agency deals with this sort of thing the rest of the country) regularly takes samples from all commercial shellfish fisheries to test for the presence of these toxins, and will close certain areas if levels are dangerous. Such closures happen every summer somewhere or other. You cannot identify contaminated areas or shellfish without laboratory testing.

And people think mushrooms are dangerous...

Yup, the only way to be sure is to have them tested. This is now done regularly. Phenomena such as the red tide were once rare. Now they occur much more often. The exact reasons for this are not clear but certainly chemicals from agricultural and lawns that run off and eventually make their way into the sea contribute. Paralytic shellfish poisoning is very deadly. Always check for local warnings. Never assume the shellfish you collect are safe for consumption.

 

[trixx]

certainly chemicals from agricultural and lawns that run off and eventually make their way into the sea contribute.

In the UK, the jury is still out on that one. Here's the relevant bit from a recent scientific review of the subject.

Shellfish toxin contamination is usually acute, sporadic and difficult to predict, as the factors governing the proliferation of harmful phytoplankton are poorly understood. However, at least in UK waters, harmful blooms are most probably part of the variability of marine flora with the evidence for anthropogenic nutrient enrichment as the causative factor being limited.

Never assume the shellfish you collect are safe for consumption.

... and never assume you won't have an aeroplane crash on your head while you are out collecting them. The chances are about the same.

 

[Ph34r]

... and never assume you won't have an aeroplane crash on your head while you are out collecting them. The chances are about the same.

God, I hate it when that happens, you are just about to grab the finest food in the area, and then WHAM!

 

[Hoodoo]

... and never assume you won't have an aeroplane crash on your head while you are out collecting them. The chances are about the same.

Well, all I can say is that if there was no monitoring and if the public is not kept abreast of phenomena such as current red tides and algal blooms, many more deaths by orders of magnitude would occur. If you think ignorance is bliss, more power to ya.

 

[locum76]

this web page from the States is interesting. It hints that the low rate of poisoning in recent times is down to good management.

http://emedicine.medscape.com/article/818505-overview

This article in the Indepenent is helpful:

http://www.independent.co.uk/news/uk-plagued-with-huge-algae-blooms-1110215.html

The skinny:

http://www.food.gov.uk/multimedia/pdfs/sfac030701.pdf

It seems that the the saying about eating shellfish with an R in the month is drivel but watch out for eating shellfish harvested from in the middle of an algal bloom - whatever the bloom is caused by.

 

[trixx]

. If you think ignorance is bliss, more power to ya.

You reckon that's my take on the subject? Muppet. I don't deny that the potential consequences can be severe, but I am also saying that there hasn't been a case of PSP in the UK for 42 years, so keep things in perspective. It's a fairly simple concept, perhaps you should read it a few times until it sinks in.

 

[zorro]

there hasn't been a case of PSP in the UK for 42 years

I think it's safe to come out now.

 

[locum76]

there hasn't been a case of PSP in the UK for 42 years

Possibly due to good risk management.

 

[Toddy]

Y'know, Scotland exports tonnes of shellfish every day, we eat tonnes of the stuff too, and I've never actually heard of anyone dying from it.
Our ancestors survived on these islands because of the shore foraging. We have literally thousands of mounds of shells, several metres high. These shell middens, all gathered, cooked and eaten by our ancestors, from the earliest mesolithic onwards, are common features and represent enormous quantities of good protein rich food. We even find carefully shaped pointy bones, for picking out winkles. The Mesolithic equivalent of the big pin given to folks who buy a bag of them nowadays
http://www.sair.org.uk/sair31/section3-4.html

Shellfish were such a common part of the daily diet, that I know of no medieval site where we don't dig up oyster shells.......in fact I know of an inland Lanarkshire monastery of the 14th century where the preponderance of shellfish remains allowed the monks bones to be preserved instead of the mineral leached away into the soil. That dig literally filled archival box loads with just shells and they're still in storage
We also know of the apprentices striking for better conditions and their demand that they *only* be fed oysters no more than twice a week.

Why is there suddenly this fuss over algal blooms and the like ?
Have they not always been with us ? are they not just part of the sea seasons ?
If there's not been an issue in over 40 years why are folks trying to cause panic now ?

I was taught the same lesson as Trixx's French acquaintance about oysters. I was told that the milky ones tasted bitter though and later on they weren't good eating until they'd recovered. The other shellfish fill the gap though. Mussels and the limpets and the razors, etc.,

cheers,
M

 

[locum76]

Why is there suddenly this fuss over algal blooms and the like ?

Eutrophication due to nitrogen rich run off has apparently made it more of an issue. Not much of a problem in Scotland (except maybe in the firths) but it is in the kategatt etc.

Have they not always been with us ? are they not just part of the sea seasons ?

Yes but they are scaled up now. Influenced by global warming maybe?

If there's not been an issue in over 40 years why are folks trying to cause panic now ?

I don't think they're is a panic really just some low key observation. It's not easy to find good info on the subject.

 

[Hoodoo]

I thought the discussion was about algal blooms and red tide in general. I didn't know the discussion was confined to the UK.

Here in the states, red tides were fairly rare 40 years ago. I was at ground zero in Newport Rhode Island while in the Navy when the red tide rolled in back in the early 70s, effectively closing the shellfish industry all along the northern east coast. It made national news. Nowadays, these events are far more commonplace. Here in the US, that is, as well as other parts of the world. If you don't have a problem in the UK, fine. I thought BCUK was an international forum.

Here is an FAQ on the red tide.

 

[mojofilter]

I thought BCUK was an international forum.

I could have sworn the UK bit stood for United Kingdom....