This paper compares total emissions of a uniformly mixing pollutant and welfare levels of a large country in autarky and with free trade with another large country that does not implement any environmental policies. There is intra-industry trade between the two countries which is modeled by using the ideal variety approach. Two abatement technologies are considered, a clean technology approach and an end-of-pipe approach. Emissions are influenced by an emission tax. With clean technology abatement emissions may be lower in the free trade regime than in autarky, with end-of-pipe abatement total emissions are greater with free trade. With both methods of abatement under free trade no emission tax may be levied at all if emissions per unit of output are very large, and if the gains from intra-industry trade due to an increase of available varieties are relatively small, autarky may yield a higher welfare level than free trade.