Chlorine Dioxide - Roach & RFB Lethality

From 4-3-15.

Checked the survival status of the cockroaches and RFB that had been exposed to ClO2 gas. The insects were exposed to the gas for 24 hours, and allowed to recover for 48 hours after that.

ClO2 & Cockroaches

The survival and health of the juvinille Madagascar hissing cockroaches was determined by gentle prodding with a forceps if survival was not apparent through visual examination. All of the five roaches exposed to the 3 grams of chlorine dioxide reagent were very dead and all of the five roaches that were not exposed to the gas were healthy and very active.

ClO2	Survival
3 grams	0/5
None	5/5

It was very interesting to see that the ClO2 seems to effect insects with exoskeletons similarly to how it effected the soft-bodied wax worms by seemingly causing their death. If the ClO2 utilizes the soft bodies of insects basically as a water sink, I wonder what is happening with the hard-shelled cockroaches that causes their demise. This was a relatively high concentration of ClO2 gas used in this experiment and they were young roaches used, however the goal of this experiment was to determine if there would be any effect - and there was. These results could warrant future investigation. Perhaps a titration curve or a pilot study to investigate the gas's effect on adult (dubia) cockroaches.

ClO2 & RFB

I checked the survival of the RFB that were exposed to 100 mg of ClO2 gas. The results were very surprising. In a reverse of what would be expected, all of the RFB not exposed to the gas were dead and those that were were still alive! I am very sure that this was the correct results and that the tubes were simply not switched around accidentally. 

ClO2	Survival
100 mg	25/25
None	0/25

All of the RFB in the control group (no gas) were completely dead and lifeless. All of the RFB exposed to the gas were very lively and active still, as though the gas hadn't effected them at all. I am unsure what caused these surprising and suspicious results. I don't believe that the RFB didn't suffocate in the control group, since the experimental group's cover was heavily parafilmed and would have likely had even less air transfer. Perhaps the ClO2 actually protected or aided in the survival of the RFB when they would have normally perished? Very odd. I will likely repeat this experiment in the near future with a higher ClO2 concentration to see if the results can be replicated....

//EWW