The most serious overall increases in pollution due to NAFTA were found in the base metals sector, the Mexican petroleum sector, and the transportation equipment sector in the United States and Mexico, but not in Canada.
NAFTAによる汚染の最も深刻な増加は、米国およびメキシコの卑金属部門、メキシコ石油部門、および輸送機器部門で見られたが、カナダでは見られなかった 。