This is one of only two episodes in the first season where a word is never "beeped". The other one is Weight Gain 4000.
Inspired by volcano-related Hollywood disaster films, such as Dante's Peak (1997) and Volcano (1997), which came out around the time Trey Parker and Matt Stone were writing the script; they considered the films two of the worst ever made. Stone said, "If you watch this episode and then go watch Volcano (1997), this makes more sense than Volcano does."
Lava and You was inspired by actual "Duck and Cover" films from the 1950s and 1960s, in which children were instructed to hide under tables or lean against walls in the case of a nuclear weapon attack. Trey Parker and Matt Stone, like many critics of the films, found the methods painfully simplistic and did not believe they would actually help in the case of such an attack.
Trey Parker said he feels many of the first season episodes considered taboo in 1997 would have been considered less controversial five years later, but that this is an exception. Since the episode involved children drinking beer and threatening each other at gunpoint during hunting trips, Parker said he did not believe Comedy Central would have aired it following the Columbine High School massacre in 1999. Parker said, "Back then, it was just sort of funny, kids pointing guns at each other, and it's just not so funny now."
Scuzzlebutt turning out to be a real character rather than a ridiculous story was the first instance of a common characteristic of the Cartman character, in which Cartman says outrageous and completely unrealistic things that turn out to be true. Matt Stone commented, "He's right more often than he's wrong".