Hallo Pete
What Triton are doing is pretty amazing and they are the first company to make it affordable, maybe none will follow for a long time, who knows.
But Triton guys, you have to be honest about the limitations of this technique. Having a physics background I understand how complex this technique is (although not the chemistry aspect of any preprocessing), separating the spectral lines of such a large array of elements with often very close interfering and strong emission lines like the sodium doublet at concentrations of 35 ppt, and getting data of elements at sub ppb levels, more than 7 orders of magnitude apart, must be very difficult and sensitive to all sorts of interferences. If you find that you can frequently get say an accuracy of 100% for a particular element but under some circumstances your accuracy drops to 500% for that element then you need to explain this, and ideally say in what circumstances accuracy will drop (ie which elements with interfering spectral lines to the ones you are using to quantify the element in question).
Well nobody says that what we do is easy, but that don´t mean it will not work. If everybody could do it and it would be easy then a lot of people would have done it already i guess.....
TBH we prooved the abilitys of the tests and the products over 7 years now and in my and a lot of users opinion ,this discussion is lets say " to late " .
Why do you think the Interference is as high ? Out of knowledge because you work with the same mashine, or do you just think that it need to be high interference ?
With an ICP-OES of the kind we use the Interfrence aspect is not as problematic as it looks like in this article ( wich is very poor part of it ).
Seperating lines is depending on the resolution you scan. Our resolution is quite high so. we have around 22000 line we could choose to test on, you just need to choose one that has no big interference, wich you do out of experimenting. what exactly is the Problem ?
This is just The part of the article that should fear people away without any scientific argument.
The 500% out value is what is one of the worse things in that "supposed scientific" Article.
Cd ( Cadmium ) is tested on 0.6 ppb and should be in the CRM at 0.1ppb. Not only that it is
not certified Value , the autors highlite it with a diviation of 500%.
While the real deviation is just 0.5 ppb ( 0.00005 mg/l ), you could also acount it as the most accurate Result in the test.
Who tells you that the deviation at 100ppb would not also be 0.5 ppb wich then would be just 0.5% relativ deviation ?
Manipulativ things like that are horrible to me, and do not belong into a scientific assament of Data.
Just fearing users of this is the only purpose of such a act.
We (users) need to see regular independent testing by third parties we trust, like the testing reported here, for us to have any confidence at all in such a tricky technique, and if you are not up front about the pitfalls with the technique you are using then you will not get the confidence that I am think you deserve for this using technique from users.
Well we have a lot confident users already, and the nicest thing to it is, in our case, the users don´t need sombody else they need to
trust even not us.
Like I said in my MACNA speach.
I want a kind of reefkeeping that is based on
KNOWLEDGE not on
TRUST.
So the best way to get a Valid answer on "will the Test work for it´s purpose for me" , is using it for its purpose.
It is a bit like you would ask sombody else if the burger you want to eat will taste good or not... and the guy you ask take the burger to a lab do some tests , and even not eat it on his own... and then tells you " well probably it will not taste good".
Better just try a burger.
So why regular Tests from third parties you
TRUST, why don´t you
TRUST regular tests by yourselfe and the constitution of the Animals you keep ?
So many users worldwide have done such kind of tests on there own, as it works anonymous ( we have done that on purpose), or just asked us about accuracy of this and that, I can not at all understand why you want to just TRUST sombody else.
Additionally the way that you report 'below detection limit' as zero might be interpreted differently to how you intend too. For example with iron displaying ppb to 2 decimal places when your LOD is 0.3 ppb for instance, this is an error to display it like this. You display < 0.3 as 0.00, meaning that a true iron level of 0.24 ppb is displayed as being below 0.01 ppb. Thats a significant error in displaying the results. The same goes with all the elements in your reports I think. When I look at the results people publish, I see 0.00, 0.00 etc, when in fact I should be seeing <0.3, <0.5 etc. Its important because everyone interprets these results as meaning absolute zero, and so when they hear otherwise they are surprised and dismayed. I do feel you should make sure its clear in the results of the limitations of the technique for each element (IE next to each element result).
This is a very valid point I will change that asap.
If you don't explain to the users
that the limitations of testing using this technique are not yours but limitations of the physics of the test itself (that is, the test that you can do for that price, not the best accuracy that can be attained if you spend 1000 times more on a test and take a month to do it), then it looks like any inaccuracy is yours. This is simply what can be done for the price. If users want to pay far more I am sure you can offer a service for that and achieve greater accuracy.
We will do that explanation in the next Accuracy and LOD PDF the way you would like it i think Interference , best detection areas and worse case recoverys will be included wich will make the TEST even a better tool.
But such things need Time and need to be Tested under real conditions, so sorry if we are to slow in this point, but we try to be very exact.
I think triton testing is great and I look forward to using the service myself but I really, really want to know what the technical limitations are. So if you have high iodine then your accuracy of tin and zinc will drop, that kind of thing. Ballpark figures for how inaccurate results will be under certain circumstances etc. And until I see a fair few independent results confirming your reported accuracies then I will be quite cautious of believing the reports completely.
We have not reported any accuracies yet pete.
All the Best Ehsan
I was simply introducing myself as someone who will be helping to guide the discussion and highlight some of the key points that may not have received enough emphasis. I also want to point out that I represent Triton-US.
