Fw: Testing each fish for mercury
----- Original Message -----
From: Padula, David (PIRSA - SARDI)
To: evertliewes@hotmail.com
Cc: palmerroy@hotmail.com
Sent: Thursday, March 02, 2006 11:27 AM
Subject: Mercury auto analysers
Dear Evert,
I am a Government researcher in Australia - we conduct large amounts of residue testing included for canned fish products for mercury in addition to other contaminants dioxin, PCBs, pesticides and veterinary medicines in Southern Bluefin tuna. This testing is done as a delegated agent of the National Residue Survey (NRS) - this data is used to fulfil trade access requirements in overseas markets around the world. Some of our reports are available on the internet at www.sbtuna.com under the "residues" link. Our main program details can be found at www.sardi.sa.gov.au under the "Food Safety" link. We are currently doing some work looking at the distribution of mercury in tuna - as the fat content of the tuna varies depending on which cut you are looking at i.e. o-toro vs. akami then this can have an effect on the level of mercury found - and hence the conclusions about the safety of that fish. The EU has specific sampling protocols that must be followed for product entering the EU for reporting of residue results.
The cost for analysis of total mercury in fish samples that we pay is $25 (Australian dollars) per sample. These systems such as you have highlighted below do need to be validated and calibrated. I don't know the specific system in detail but you would want to ask a lot of questions about its robustness to handle high fat content samples, potential interferences, limits of detection, linearity of response, reproducibility of results, calibration, acceptance of data by importing country competent authorities, what technical training is needed, how much do the reagents cost, what is the operating cost of the instrument and all the disposable products needed, glassware, are the waste products safe to dispose down the sink etc. I have seen a different automated system promoted at a conference in New Zealand last year.
You need to remember there are different chemical forms of mercury - the US FDA MRL is set based on methyl mercury. Methyl mercury costs about $250/sample to test for and is quite difficult to do. Is this instrument able to test specifically total mercury or methyl mercury or other organic forms of mercury? I have some doubts about these rapid mercury analysis do it yourself type kits - they generally are quite expensive in the order of $200,000 US to buy - plus the OH&S issues of handling mercury standards and ongoing costs for reagents and consumables etc. We only use accredited laboratories for our testing to satisfy product integrity requirements. Mercury analysis is quite a specialised area and there has been many decades of work put into developing classical methods such as AA or ICP-MS which have stood the test of time. If this instrument is so good let them publish a study by an independent group on a comparison of their instrument vs. the classical methods and quantify the costs in a peer reviewed journal.
There are some semi automated mercury analysers using flow injection analysis which are quite robust - however all of these instruments require a lot of technical training and experience to operate. You really need to look at how many samples/year are you analysing and make a judgment as to whether it's worth setting up a lab to do the testing yourself. Are you testing individual fish or composite samples?
Cheers,
David
____________________________
David Padula
Research Scientist - Epidemiology & Sampling
SARDI FOOD SAFETY PROGRAM
33 Flemington Street
Glenside SA 5065
Phone: (08) 8207 7939
Mobile: 0422 000 020
Fax: (08) 8207 7854
Email: padula.david@saugov.sa.gov.au
_____________________________
The information in this e-mail and attachments (if any) may be confidential and/or legally privileged. If you are not the intended recipient, any disclosure, copying, distribution or action taken is prohibited. SARDI, The South Australian Research and Development Institute, is the research division of Primary Industries and Resources (SA)
----- Original Message -----
From: "Evert Liewes" <evertliewes@hotmail.com>
To: "Liz Brown" <bfeab@uaf.edu>; "seafood" <seafood@ucdavis.edu>
Sent: Wednesday, March 01, 2006 3:03 PM
Subject: Testing each fish for mercury
> Hello
>
> I read the article and was surprised to read the that Micro Analytical
> Systems has a system available to test large numbers of fish very quickly.
> We produce canned tuna and take large numbers of samples for mercury
> testing. Based on a risk assesment we will sample all lots of incoming
> fish. When we find higher mercury levels, mostly associated with larger
> fish, we do more testing in order to understand how the mercury is
> distributed with fish size. If mercury levels are high (over 0,5 mg/kg) we
> size the fish more accurately and sample and test again. Subsequently
> large fish may be sampled individually and rejected.
>
> This works well, but generates large numbers of samples. A fast working
> testing system therefore is attractive. How accurate is the system of
> Micro Analytical Systems? What does it cost per analysis, compared to the
> traditional methods? Any info will be appreciated.
>
> Evert Liewes
> Princes Tuna Maurititus
>
> ---- Original Message -----
> From: "Liz Brown" <bfeab@uaf.edu>
> To: "seafood" <seafood@ucdavis.edu>
> Cc: "Allison Rice" <fnar@uaf.edu>; "Bristol BayTimes"
> <bbtimes@nushtel.com>; "Bob Shavelson" <bob@inletkeeper.org>
> Sent: Wednesday, March 01, 2006 1:56 AM
> Subject: Testing each fish for mercury
>
>
>> http://www.latimes.com/business/la-fi-fish27feb27,1,3246852.story?ctrack=1&cset=true
>>
>>
>>
>>
>> --
>> Liz Brown
>> Marine Advisory Program
>> University of Alaska Fairbanks
>> PO Box 1549
>> Dillingham, AK 99576
>> 907-842-1265
>> Fax 907-842-3202
>> www.uaf.edu/map
>>
>>
>
>
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