Monday, April 8, 2019


First of all there is a long and involved story behind the expression "cargo cult" science. Suffice it to say that it has a meaning similar to junk science, psuedo science, fake science, scientific gibberish etc.

Last week I posted here about my reviewing the MOE 2012 and 2013 studies of DDT and dioxins in Canagagigue Creek sediment and soils. Indeed I found that those two reports had sample results anywhere from ten to twenty times lower than the latest 2019 Canagagigue Report. That report had its samples taken in 2017 with both soil and sediment samples having a detection limit that started at 20 parts per billion (.020 Parts per million) and often rose to 30, 40, 60 and even higher detection limits for some samples.

At first blush I saw that sediment samples with their very low criteria for DDT compounds of 5,7, and 8 parts per billion (ppb) would be most adversely affected with a detection limit of 20 ppb. in the latest Canagagigue Report (March 2019). By adversely affected I mean that exceedances of their criteria would be masked and greatly reduced by Non Detect (.020) results. Then I looked more closely and realized that soil results even with their much higher MOE Table 8 criteria of 50 and 78 ppb. would also be reduced with detection limits of 20 ppb. much less the higher 30, 40, 60 etc. detection limits. This is because soil results similar to sediments are calculated from adding 2,4 DDD + 4,4 DDD together as is DDE and DDT. Therefore these criteria are two numbers added together which means that ND (.020) ppm. carries much more opportunity to mask actual detections. For example as happens frequently if 2,4 DDD is at 39 ppb and 4,4 DDD is at 12 ppb then the 50 ppb. criteria is exceeded. Unfortunately with the high detection limit of 20 ppb. those results would end up as 39 ppb. + ND (.020) = 39 ppb. which is lower than the MOE Table 8 criteria.

There is yet another problem with the latest report. I compared it to the 2012 and 2013 MOE reports and found that those older MOE reports had much lower detection limits. This weekend I looked at the soil sampling reports done in 2015, 2016 and 2018 by GHD along the Chemtura/Lanxess property line with the Stroh farm. You guessed it. In those reports GHD was able to achieve detection limits for DDT compounds in soil as low as six and seven ppb. in 2015, 2 ppb. in 2016 and 2, 10, and 15 ppb. in the 2018 report. All of this begs the question why the March 2019 report was unable to achieve those same sampling results and possibly more importantly how that has impacted upon the quality of the data presented in this latest report. After all detection limits far in excess of the MOE Table 8 criteria, which by the way isn't even the most stringent criteria, mask, hide and reduce the number of samples which exceed the criteria giving the appearance of less toxic contamination in the Creek than there actually is. In fact even when high detection limits aren't actually higher than the criteria they can also diminish the number of exceedances found as demonstrated in the previous paragraph.

The reason for all of these high detection limits in my opinion whether done intentionally, unintentionally, maliciously, incompetently or for whatever reason is not terribly relevant. What is relevant is that the quality of this entire report is incredibly degraded by these high detection limits. Science is supposed to clarify and use best efforts to help us understand. Massive numbers of non detect values at or below the various criteria/standards would greatly assist us to understand the extent of contamination in this Creek. Massive numbers of non detect values however anywhere from 2 1/2 times to 12 times higher or more than many different criteria does the opposite. It muddies the waters and may even allow the unscrupulous to interpret the data with self-serving flair and imagination.

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