brose wrote:Maybe I missed where the information was given, but this Greenpeace report shows a lack of disclosing information and attempting to sensationalize what they found. They should have disclosed the lab and techniques used to analyze contents. Anyone who has taken a chemistry course should know that reporting numbers without giving the errors and detection limits of the instruments is absolutely essential to validate results. For example in Annex 2 Zhang Yiyuan Jasmine Cloud Tea has 0.07 mg/kg of Chlorfenapyr if the error is +/- 0.14 the number really dosen't mean that much (hopefully any self respecting analytical company would have better standards, but the report leaves you guessing). Ideally there would be no contamination, but for me the question is not IF something is present, it is in what concentration is it present. An example of this is arsenic in drinking water: it does not pose much of a health risk, as long as its concentration is sufficiently small (in the ppb or less range). All of this is in addition to the complete lack of comparison to the regulated limits for other countries mentioned above. Shame on Greenpeace. Good intentions, terrible execution.
When reading the report, I decided to believe all the data have proper confidence intervals, mainly because there are industry standards of the pesticide inspection and it's not that hard to do a good job on it. Since a lot of government standards I saw from USDS database are accurate to 0.01 level, I guess it's because that's the level technology could accurately detect.
But I fully agree with your last three sentences in your comments - lack of valid comparison, no valid conclusion. Good intentions, terrible outcomes. I feel even a well-trained science major sophomore could do a better data analysis and report. And I don't think it's because of the incompetency of Green Peace - it's a big organization with respectable human resources. What disturbs me is the seemingly arrogance behind such unscientific attitude. It's almost like saying, "This is from The Green Peace, take my data, have faith in my words and don't question my methods."