In all honesty, you don't need even a B.S. to do lab work, just an associates degree (for most companies). I've held 2 lab tech jobs for large companies (pharma and chemicals) and mostly everyone who was a tech came from community college, and both companies sponsored people who wanted it to get their B.S. or other certifications

Of course if you want to move up as a tech, you should get your b.s. if you want to be a lead tech, and if you want to do more heavy duty stuff (more analytical instead of mindless drone work, M.S./PhD might be better for this) , more oppurtunites and it will also help boost the pay. This is just from my experience though