I thought it was a typo or phonetic spelling for paint. The humor is that the misspelling is from brain damage from eating lead paint chips. Eating paint chips is something young kids do and has resulted in stunted mental growth due to the lead in older paints. Consequently, the lead has been removed from household paints since 1978.
https://www.familyhandyman.com/article/when-was-lead-paint-banned-why/