We modify a model of climate and economy to address the effects of the reduction in atmospheric pollutants which occurs as a result of climate change mitigation policies. In particular, the reduction of sulphur emissions as a result of climate change policies leads to reduced statistical morbidity and infant mortality, but increased short term climate change. It remains the case, even with the consideration of secondary benefits, that there are welfare costs of GHG emission control to almost all working-age agents alive when the policies are imposed, which suggests that the consideration of secondary benefits alone may not be sufficient to provoke aggressive action on climate change.