Seedlings are sick - need help identifying problem

[kameronth]

I need some help identifying what problems my seedlings are having. I reuse my seed trays but I do clean them out with 10% bleach solution each year to help prevent disease. Most of them have leaves dying (not just the cotyledons) yellowing, and slow growing. They are about 3 inches under lights and the ambient air temp is 68 degrees.



I've experienced damping off before but with that, the stems are are weak. I'm not seeing that in any of these.


My other seedlings such as petunias, peppers, night stock also have some damage but not near the extend of the tomatoes.



Could it be ethylene damage or tobacco mosaic virus? I ask because I was (stopped) parking my diesel pickup in the garage where the seedlings are and it will smoke a little on startup. Also, I made the mistake of enjoying a cigar a while ago and forgot to wash my hands before handling the plants.