The ninja turtles were made when radioactive waste fell off a truck that hit a bowl out of a little boys hands,
the turtles were sent down a storm drain were master splinter was at the time running away form the shredder that just killed his owner.
The glass that the radioactive waste was in broke and too went down the sewer,thus causing the turtles and master splinter to mutate.Master splinter took the turtles in as his sons, That is how they were made.
Leo
Rahpe
Mikey
Donnie