Environmental risk factors such as factory emissions, car exhaust, and tobacco smoke threaten communities worldwide. With many parts of the world industrializing at rapid rates, environmental factors are jeopardizing large portions of local and global communities by exposing individuals to agents that are responsible for lung cancer, emphysema, and carbon monoxide poisoning, among others. The public health profession continues to adapt quickly to find innovative solutions – using research, policy implementation, and educational offerings – to help curb the effects of environmental risk factors.


Water scarcity affects one fifth of the world’s population.

Less than one percent of the world’s water supply is potable and readily accessible, and every continent is affected by a degree of water scarcity. Water quality, scarcity, and food security are important factors in securing fresh water. Climate change, inequitable distribution, and conflict areas also stress the world’s water supply.  The United Nations reports that one- quarter of the world’s population is affected by economic water shortages, where a country has sufficient water resources but not the infrastructure to deliver it to citizens. The public health field is committed to alleviating global water stress- by developing water and sanitation campaigns, advocating for improved infrastructure, and establishing human rights protocols for water distribution and sanitation.

88 to 4 The percentage drop in blood lead levels in children after the CDC fought to reduce lead in American gasoline.


As developing countries industrialize, air pollution remains a growing threat to public health.

Much progress has been made to reduce carbon emissions—most notably the Kyoto Protocol—signed by more than 190 nations collectively committed to reducing greenhouse gas emissions over the long-term future. Although major legislative triumphs continue to ensure safer air quality, the World Health Organization (WHO) estimates that 1.3 million people die every year from the negative effects of outdoor air pollution. WHO singles out ozone, nitrogen dioxide, and sulfur dioxide as commonplace industrial emissions that can negatively affect the health of large populations by aggravating bronchitis, asthma, and other chronic respiratory illnesses. Public health officials continue to push for legislation that regulates carbon emissions in countries across the globe, ensuring efforts to limit the effects of harmful pollutants near high-density populations.