Thursday, February 9, 2017

SPECIFIC NUMBERS & DATA FOR FISH & BENTHICS IN THE "GIG"



Following are some big picture concentrations of contaminants in fish as well as survival rates of benthic organisms exposed to Canagagigue Creek sediments. That the sediments and their toxic contaminants are both lethal and biologically available to life further up the food chain is obvious. Equally obvious is that the Ontario Ministry of Environment are corrupt liars running interference between big polluters and local citizens adversely affected by the pollution.

There are five different sediment locations tested. Two are on the Chemtura site, two are downstream of Chemtura and one is a control site referred to as Peche Island. That site presumably is clear of sediment contamination as the test's validity is based upon 70% of the benthic organisms involved surviving 10 days in dechlorinated Toronto tap water sitting above the previously mentioned sediment samples. The dechlorinated and heavily treated Toronto tap water seems a tad bizarre to me but we will go with it for the moment. Also the most upriver Chemtura site is referred to as site 30 and it's right at the bridge (Hwy #86-Church St.). Frankly it's bad news in and of itself for Chemtura and the M.O.E..

The first benthic organism is Chironomous dilutus. Five samples produced survival rates after 10 days for the Peche Island sediments of 80-100 percent. Excellent. Unfortunately the four sediment samples from Chemtura and downstream weren't quite so healthy. Site 30 survival rates were between 60 and 80 percent. Site 750 at the south end of Chemtura had survival rates between 30 and 70 percent. Site 20 just past the Chemtura property line had survival rates between 60 and 100 percent. Interesting. Site 21-U1 near the New Jerusalem Rd. bridge had survival rates between 20 and 100 percent. Strange? Obviously these Canagagigue Creek sediments are toxic to this particular ubiquitous organism even after only a few days exposure.

Hexagenia spp did much better and clearly is a hardier (to pollution) organism. All the survival rates were between 80 and 100 percent with the exception of Site 21-U1. While three samples had 100 percent survival, one had only 70 percent and the other 10 percent. Oh my. This was a 21 day test which to me indicates that the testers knew in advance that Hexagenia were more pollution resistant.

This same organism was then tested for a 28 day period including Bioaccumulation tests. What the researchers were looking for was uptakes into their tissues of a DDT metabolyte as well as Dioxins and Furans. Unsurprisingly based upon sediment concentrations of these toxic contaminants, indeed they were bioaccumulated into the organisms. The only DDT metabolyte tested for was pp DDE and it had concentrations in tissues at Site 20 of nearly 24,000 parts per billion (ppb) and at Site 21-U1 of nearly 8,000 ppb. Dioxin and Furan uptake was much lower with 4,000 to 7,000 plus parts per trillion (ppt) uptake into the tissues of the organism. This of course is the start of the food chain bioaccumulation as fish and other life forms in the creek eat these benthic organisms.

Fathead minnows were tissue sampled after 28 days exposure to the sediments as well. More DDT metabolytes were tested and the results were much higher. The highest results were between 8,000 ppb and 35,000 ppb in the fish tissues at Sites 20 and 21-U1. Dioxin concentration of the most toxic type (2,3,7,8 TCDD) was just over 7,900 ppt at Site 21-U1.

Lastly a benthic organism referred to as Lumbriculus variegatus received a 28 day bioaccumulation test. It too bioaccumulated DDT & metabolytes up to 13,700 ppb at Site 20 and 6,600 at Site 21-U1. 2,3,7,7 TCDD was up to 7,600 ppt at Site 21-U1.

Tomorrow I will give you the readers some of the fish results. These include carp, suckers, chubb, shiners and minnows. They do not include the top predators in the creek namely pike and bass. This most likely is because those top predators will of course have the highest concentrations of toxic contaminants in their flesh. Also keep in mind that the M.O.E. have set up this study very carefully. By focusing their sampling all very near the Chemtura site; even if they can't avoid admitting there is a problem they have pre-limited the size and scope to just a small fraction of the entire five miles of contaminated creek all the way down to the Grand River. If Chemtura Canada are not paying off top M.O.E. officials then they surely should be based upon their services to them rather than to the public.




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