Bro, they were firing old school clearomizers with a starting wattage that's at the top of what's recommended. You can tell by the conversation graphs because EC3 is a more modern tank and it's an order of magnitude lower.

There's a reason why clearomizers didn't stay around long. They designed this study to produce DHA. You can tell because there was no change in EC3 across the temperatures, yet they scaled their graph to make it look comparable to the clearomizers. And the levels in EC3 were so low that it could have easily been machine error given the way they had to measure it.

The amount EC3 produced is 50x lower than the lowest amount the mice were exposed to.

If you use a temperature controlled mod, this is all a non-issue.