Im growing some black seeded simpson lettuce and i just noticed i have these clearish spots appearing all over them not sure whats wrong i did use some pyrethrin to try and kill the aphids not sure if i damaged them with it.

Tender leaf plants seem to be damaged by aphids, and aphids can also cause damage like that.

Keep a close eye on those lesions.
They could be insect damage, in which case it's merely cosmetic, but they could also bacterial leaf spot. If those spots turn brown, expand etc and/or you notice tiny black spots on the leafs it's leaf spot.
Copper-based fungicides such as Boredeaux mixture usually work but many lettuce cultivars find copper toxic. The best solution is to destroy the affected plants, rotate cultures and switch to a leaf-spot resistant cultivar.

I wouldn't use a pesticide on something I'm going to eat raw, such as lettuce. I would switch cultivars and even planting locations.

repentantslide said:Tender leaf plants seem to be damaged by aphids, and aphids can also cause damage like that.

I meant tender leaf plants seem to be damaged by pyrethrin. Sorry.

As far as pyrethrin toxicity goes, it's really bad for insects and fish, but humans could pretty much drink the stuff straight, let alone a bit of low concentration residue on the plant. I can't blame anyone for avoiding pesticides and herbicides for any number of reasons, but as far as science goes it should be safe.

Good to know! I generally avoid all pesticides. I do use Spinosad on rare occasions.