Continuity mistake: Lana was found shot in her upper left shoulder but at the end of the show she has a sling on her right arm. (00:42:00 - 00:43:05)
Continuity mistake: The water level in the glass that Lex taunts Aquaman with changes levels throughout the scene.
Continuity mistake: After Lex confronts Desiree about changing her name, Lex says 'we really need to discuss this' Desiree then kisses Lex and they both tilt their heads to their left. Cut to a different angle and they are both tilting her heads to the right.
Continuity mistake: Lex's aide is shot in the back as he makes a run for the door. When he goes down he slides head first almost all the way to the door. A few moments later, just as Flynn shoots out the security camera, in the security monitor image Lex's aide is now in a different position.
Continuity mistake: After the credit card company calls the Kent's to confirm purchases made the night before, we see Jonathan holding a mug by the rim. They then notice the music coming from Clark's barn and go to investigate. Cut to a different and now Jonathan is holding the mug by its ear.
Continuity mistake: When Clark goes to Kwan's house the set of pathway lights on the left, the side where Justin pulled only one out, is gone. Earlier the lights ran down both sides of the driveway.
Continuity mistake: Chloe is sneaking around inside the warehouse that Lex is using to hide the space ship. After she is found by a security guard she turns back around to look in where the ship is. When she does a shot from her POV shows the fan blades spinning faster then they were in the shot before and after when we are looking at Chloe through the fan.
Continuity mistake: When Jonathan runs up to Lex, while he is unconscious, the first shot of Lex has his arm bent but not near his face. The shot switches to look down on Lex and now he is laying with his hand considerably closer than the previous shot.
Continuity mistake: The meteors are shown traveling together in space at the beginning, but the smoke trail from the first meteorite runs perpendicular to the flight of the next one. They should be falling along roughly the same flight corridor, as all the other meteorites do. (00:00:10 - 00:04:30)
Continuity mistake: When Clark first enters the club, the stripper on stage is taking her top off, then in the next shots of her, she still has her top on.
Continuity mistake: At the beginning when Clark and Lana are on the small pier by the lake, it alternates from sunny to shady between shots during the scene.
Continuity mistake: As Lana says "I was thinking the same thing but we don't seem to be very good at it." there is a camera change as she says "but". Before the change she only has the red cup on the tray but after the change, even though she didn't pick it up, she has a red and a yellow cup on the tray. The other cup was on the table and jumps to the tray between shots.
Continuity mistake: When Chloe crashes through the bridge rails her windshield is dotted with raindrops. Just a few seconds later the blue truck hits her car from behind and now her windshield is dry.
Continuity mistake: When the offensive line is first shown, as they sit on the bench, the shot is of them from behind. In that shot the team jersey numbers are in this order 89, 46, 8, 66, 1. Then the camera view changes to be in front of the players only now going from the players left to their right is 99, 46, 8, 66, 89.
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: Nell meets up with Lana to talk to her about moving to Metropolis. We see Lana going up to Nell while riding a horse. She then stops and is about to dismount when they cut to another angle but now Lana is dismounting yet again.
Continuity mistake: At Ryan's surprise welcome back party, Clark puts his right hand over Ryan's shoulder as he asks him "you knew about this didn't you?" Cut to a different angle as Ryan responds "I was tempted too" but now Clark's hand is no longer on Ryan's shoulder. Cut to Clark then back to Ryan and now Clark's hand is back on Ryan's shoulder.
Continuity mistake: As Pete gets into his car the shadow from the car is extending out away from the passenger side of the car. As Pete starts to drive off, just a few seconds later, the shadow is now extending out past the back of his car.
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