Continuity mistake: Martha asks Clark to come out after he gets glasses. In the shot showing all three of them, Clark comes into view on the left side of the screen and is turned toward his parents. The very next shot shows he is just walking through the door of the optometrist and turned away from his parents as he closes the door.
Continuity mistake: When Lionel and Lex are talking, after they sit down, near the end of the conversation, Lionel asks who Lex's source is. Lex is looking straight ahead. In the next shot, we see Lex turn his head to face his father. In the next shot, Lex is looking straight ahead again.
Continuity mistake: As Lana starts her second swing at Chloe with the axe while the camera is in front of Lana Chloe is just barely getting up and is still close to the floor. The camera switches in mid-swing and suddenly Chloe is completely standing and is able to jump back to dodge the swing.
Continuity mistake: When Molly first starts flipping through the disks for Lex, she has a ring on her left ring finger. After Lex talks about just getting back Molly is shown still flipping through the disks only now the ring is gone.
Continuity mistake: In the head on shot of the car that almost hits Mr. Altman you see the driver of that car react by turning his car to the left. In the very next shot, as Clark and Mr. Altman are just coming to a stop after Clark's high speed rescue, the driver is now turning his car to the right, as shown by which way his wheels are turned.
Continuity mistake: When Adam says "It's nice to be appreciated" Lex is looking at Adam. In the next shot, as Lex says "strange thing is." and now Lex is looking down at the file or piano.
Continuity mistake: After Dante says "...if you want to turn that tortoise into a hare just give me a call." he walks off and the shot follows him as he walks all the way over to a black car and starts to work on it. The shot returns to Clark and Pete and Dante is shown walking away again on the left side of the screen.
Continuity mistake: At the start of the final race there is a bridge at the far end of the road that Pete and Jason are going to race to. During the entire race they never pass this bridge yet it ends up behind Jason's car when Pete looks in his rearview mirror as the crash is going on.
Continuity mistake: As the two racers speed past Clark and Martha, in the truck at the intersection, Pete's red car does not have its neon lights on in the back window and under the rear spoiler. Then in the next shot, while still racing, both the blue neon lights in the back window and the green neon under the rear spoiler are on.
Continuity mistake: As the car that Jason was in comes to a stop after the crash you can see Pete's red car is nowhere near the wreckage of Jason's car. In the next shot Pete's car is shown rolling forward to a stop, meaning he hadn't backed up but was still going forward and stopped where he was, but now Pete is only 30-40 feet from the wreck of Jason's car.
Continuity mistake: During the scene when Jonathan comes home from the hospital the length of rolled up sleeve on Jonathan's left arm changes between shots. As Jonathan says "Low sodium turkey?" the sleeve is down to just about touch the watch he is wearing. When the camera jumps to Jonathan's left side, as Martha turns around, the sleeve is now several inches higher and further from his watch than it was before. Jonathan does nothing to his sleeve between shots.
Continuity mistake: In Pete's rearview mirror there is only a couple of hundred feet between Jason's car, which is in the process of crashing at the time, and the bridge. In the next shot of Jason's car almost a mile away from the bridge. Drastically different distances.
Continuity mistake: The field trip is supposed to be on the 39th floor, as stated by Clark and the sign next to the elevator. The view outside the large windows as Lionel is talking shows that they are no more than 5 stories up.
Continuity mistake: As Alicia holds the kryptonite on Clark her hand turns between shots. While she says ".but you broke the rules first." there is a camera change. Before the change the frontal view of Alicia has her holding the kryptonite with the glowing part straight up. After the camera change she is now holding it so it points to her left.
Continuity mistake: While Alicia is in Clark's bed she says "I know you wanted to kiss me, Clark." and while she says this her hand is on Clark's face. The very next shot shows her hand is nowhere near his face.
Continuity mistake: When Alicia confronts Lana in the Talon, when Alicia says, "you're definitely not smarter" Alicia has the knife right on Lana's cheek. When the camera switches to behind Lana, as Alicia says, "You don't have my abilities" the knife is not on her cheek.
Continuity mistake: After Adam says "Look who's talking." you can see Lana raise the notebook she found as she starts to respond when the camera is behind her. When the camera jumps to the other side, facing Lana, the notebook is down instantly between shots and she has to raise it up again.
Continuity mistake: The bomb that Garret wears has four kryptonite section, one at each of the corners, and each section has three distinct pieces. The pieces glow only from the center core and the outer edge is only green colored and is not glowing. When the shot switches to the CG shot of Garret falling, The camera passes over and grabs the bomb and now the krptonite has a uniform glow and there are now the one block on each corner does not have the three individual pieces.
Continuity mistake: Garret is shot in the chest and the bullet is shown as hitting on the right side. Then, in the special effects shots as time is stopped and Garret is in mid-fall, his bullet wound is now on the left side of his chest.
Answer: The kryptonite only creates mutations when it reacts with the environment and an individual. Remember, the FDA and several environmental groups did check out Smallville after the meteor shower, but found no danger in the rocks. Obviously they're not always emitting mutating rays, or all the flora and fauna of the surrounding area would be horribly mutated.
Phoenix