Continuity mistake: Notice when the sheriff hands her daughter the stun gun its metal prongs are pointed down for safety for her daughter, but then it shows a close-up of the stun gun and the prongs are pointed up instead of down. It goes back and forth a couple times doing this. (00:22:50)
Continuity mistake: When the cop's beeping his horn outside the car as the spiders jump towards him, he's glaring at the house until the shot of the spider landing on his roof, when he's staring fixedly ahead (not at a spider - there aren't any in front of him). Next shot he's glaring at the house again. (00:53:30)
Continuity mistake: As the cop car arrives at the trailer radio station, the pattern of goo on the windshield changes between shots. (00:55:00)
Factual error: Due to the way in which a spiders respiratory system works it would actually be impossible for the spiders to breath as their box lungs would collapse and their primitive circulatory system wouldn't get enough oxygen around the body.
Continuity mistake: Just after the female sheriff's daughter is attacked by one of the giant spiders there is a scene where the sheriff is holding a double barrel shotgun and hands David Arquette a pump action shotgun. A few seconds later the sheriff has the pump action shotgun and David Arquette has the double barrel shotgun. (00:54:15)
Answer: Both! The owner of the spider farm was feeding the spiders bugs from the water that had the chemical spill in it. The bugs were contaminated with the chemical, thus contaminating the spiders. Note: The man who owned the spider farm had no idea about the contaminated water.
SAZOO1975