YMMV / Supergirl (2015) S3E5 "Damage"

• Fridge Brilliance: The fact that only children were exhibiting signs of lead poisoning is actually the first sign that something was off with Edge's claim that Lena's lead bomb was responsible. The bomb detonated citywide and affected everyone, not just kids. There should've been a significant percentage of adults, mainly those with prior health problems, exhibiting signs of lead poisoning along with the children. The fact that there weren't indicates that the children were exposed to lead (or, in the case of the episode, something simulating the effects of lead poisoning) from another source — somewhere where children could be commonly found, like a public pool. Plus, there is the fact it seems to be limited to a single city, while the bomb was supposed to affect Daxamites everywhere on Earth.
• Harsher in Hindsight: When Lena drunkenly tells Kara she can't hide anything from her, Kara mutters that Lena would be surprised at what she hides from her. This is a reference to her secret identity. While this was meant to provide some comic relief in a darker episode, it actually comes across as cruel in retrospect. Kara doesn't really have an excuse for withholding the truth and comes across as Kara mocking Lena and also eventually being the main reason for Lena turning into a villain.
• Moral Event Horizon: Edge went as far as to poison children just to make it look like Lena accidentally gave them lead poisoning, and he did it just to get back at Lena for buying CatCo out from under him.