View Full Version : All about being safe to eat.

29-11-2007, 08:25 PM
Now there have been some interesting threads on water quality and some interesting comments and experiences concerning eating fish from " interesting" places.


Does any body have some solid information on what sort of contaminants get into the eddible flesh of fish and how.

Ther are all sorts of emotional responses about eating fish from certain places, and a perception of some places being clean and others not, and some fish being good and others not form certain places.

I know that some enviroments can impart a certain flavor int the flesh..... the fish tasting weedy or muddy.

I would expect the realy nasty things like heavy metals and pestacides particularly organophosphates would most certainly find their way into the flesh and also move up the food chain.

But what about bactierial coantaminants.

any comments or ideas.

29-11-2007, 08:56 PM
Pretty hard for bacteria to contaminate flesh in any systemic way, the bacteria must first survive a acidic stomach acid, the endo and exo toxins produced by bacteria that are lyced and before being lyced by this environment might invade but the dose would be small when consumed by such a large organim as ourselves.

Oysters are a shocker! cannot think of any reach/river or estuary Aust wide where I would take the chance natural.

Mudcrabs etc are another worry from a dioxin and heavy metal point of view.

If you are a smoker then the problem pails somewhat due to te toxins imparted anyway in that choice.

Apart from oysters and their efficiency in bioaccumulation as filter feeders, pathologic viruses/bacteria from animal/human waste is always a consern.

It took 20 years for someone to do something about the known dangers in Syd harbour silt and the related consumption by those not so important in society.

Don't expect any authority to warn the common bloke if there is a very real and higher than guidlines risk in consuming a catch here in OZ. It's not how it is done - unless of coarse the risk is so high that the trail will be sniffed directly back to any government monitoring organisation who did already know.

cheers fnq

29-11-2007, 11:25 PM
Don't worry about bacteria mate, about half of our number 2s by weight are dead bacteria....

Yes, I know that has little to do with the question, but I was so startled when I read it that I share it every opportunity.

You raise issues that I wonder about too..... just why is it that organochlorides disappeared so quickly and so quietly from the shelves??? Are they another asbestos, but in this case, being kept low profile?

30-11-2007, 09:06 AM
I could never come at molouscs..... oisters in particular........ apart form the look and feel of the slimy things.......the blasted things are inside out... & you eat all of them.

how many people would eat the guts of any fish......I recon that would be an easy way to get sick.

whats in the guts and whats in the flesh are two very different things.......this is why for best food quality fish are best gitted and washed out as early as possible........ an ungutted fish ( well and animal) will rott from the inside out if not gutted.

no not ceen at all on oysters.


30-11-2007, 09:48 AM
About 2 years ago I read an EPA article, maybe even on here, or the news, about the dredging of Brissy river to deepen it. They were reclaiming the sand to extend fishermans island / container port area. Each load is measured by the EPA, and most loads were high in DDT.

There was one 'vein' of material they tapped into where the DDT levels were 200 times the 'acceptable' levels so they had to dig a 50 foot deep trench and bury the soil. If the soil is say 50 times acceptable level, they take it out about 20 miles to sea and dump it apparently

People say things about fish migrating and not being round long enough to absorb these contaminents, I really hope so, I read so much about guys eating fish they catch in Brissy river.. I know a guy who works for a company who are on the river side. He used to put pots out on their dock when he knew ships weren't coming in. He gave up after a while because so many of the muddies he caught either stunk when he cooked them, or they had visible sores etc on their carapces.

BTW, I eat Oysters, I love em, but nowdays I can't bring myself to eat them raw, they have to be mornay or Kilpatrick (or is that Kilsanchez) ?

30-11-2007, 09:54 AM
In a sort of a way, I guess it matters very little where the fish was caught, like (say) you may have just caught a nice Bream on a pristine Beach, but for the last 10 years it lived in some toxic City creek and only just went to the beach yesterday, and things like Lobsters and Prawns, we all love them and pay top dollar for them, but in reality, they are just the "maggots of the Seafloor" I guess things that are "fixed" to structure (like Oysters) may be impacted greater by water quality than things that just come and go, but I still love Oysters, and eat them all the time.

30-11-2007, 10:13 AM
Bacterial contamination of foods can and does come from contact. That is to say that if problematic bacteria are in the water and therefore on the fish itself they can then be transfered to the flesh by hands, knives , cutting boards ,when the fish is being prepared.
This probably happens to all fish no matter where they are caught.
The real problem occurs if conditions become favourable for that bacteria to multipy in numbers sufficient to cause illness.
Much of Brisbane river has high counts of "Fecal coliforms" one of the bacteria present in shit.
It can make you ill.It is also already present in your gut.
If condition are right for it to multiply unchecked ,,, you get sick.
So yes there is a risk. How great it is I dont know.
The best person to answer that would be a microbiologist.