Responses to the threat posed by antimicrobial resistance have been inadequate. Most attention has focused on the emergence of resistant organisms in human medicine and in agriculture. Much less attention has been given to antibiotic contamination of the environment. To assist health advocates to engage with this issue, we review the evidence on the role of agriculture, aquaculture, domestic waste and pharmaceutical manufacturing in the spread of antibiotic resistance, concluding that all of these activities pose a potentially serious threat. We then examine ways that this threat might be mitigated by specific measures, such as improved wastewater treatment processes, reduction of manufacturing emissions, consideration of environmental impacts in procurement and drug approval decisions, and better manure management. We conclude by placing this problem within the growing literature on commercial determinants of health, stressing the need for effective legislation and regulation developed independent of vested interests.