Milk question for BRAWM or anyone who can clarify/confirm
I just looked at milk results and the PRE-fukushima levels seem higher than the LATEST (5/30/2011) homogenized milk results, including cesium 137.
Can you confirm/clarify if the levels in milk are now LOWER than than were pre-fukushima? Based on the numbers found here http://www.nuc.berkeley.edu/node/2174
It SEEMS that is the case. If not, what am I failing to look at?
I think that you are looking
I think that you are looking at the red line, which shows "Minimum Detectable Amount. This line is variable due to sample size and other conditions (testing time, instrument used, etc.)
The measured levels are the blue dots.
We are not pre-Fukushima, and will not be for a long time (as far as actual amounts here, not "bio-accessible necessarily, reference 30-ish yr half-life of C-137) , but we probably will be below MDA for these tests in the somewhat foreseeable future.... Unless things get poopier.
BC
Plots vs numbers...
Ok, I see on the plot the levels are still up compared to the red 'baseline', but if you look at the actual number chart below the graphs, it says the levels are lower compared to pre-fukushima. I'm no math major, but do the charts and numbers match up?
Are you confusing the
Are you confusing the "original data" table with the revised data? We have kept a separate chart at the bottom of the milk page because on 4/13 we made a major adjustment in our milk calculations. That table was kept there for those who still wanted to see our original, not-as-accurate calculations.
The only pre-Fukushima milk sample we have is the first one (Best By 3/25).
Mark [BRAWM Team Member]
But how do we know there was
But how do we know there was no radioactive cesium before if no organization was testing the milk before the accident at the levels of accuracy BRAWM is using now?
In other words, how much of the cesium being detected now is the result of nuclear weapons testing or Chernobyl?
The first milk sample is the
The first milk sample is the only one that is for sure pre-Fukushima. It had a Best By date of 3/25, meaning it was bottled around 3/7. Unfortunately, we didn't set good limits on I-131 with it, but we set pretty good limits for Cs-134 and Cs-137 that were exceeded by later samples. These limits, and the clear trends in the detected Cesium activities, both lead me to conclude that any previous presence of Cs-134 and Cs-137 was less than about 0.1 Bq/L.
Mark [BRAWM Team Member]
I see, thank you very much
I see, thank you very much for your reply!
So, we should ignore the MDA of 0.15 for Cesium-134 and 0.34 for Cesium-137 of the first sample?