Quantify the scale of water contamination from emerging pollutants (PFOA, microplastics, pharmaceutical residues), assess the adequacy of treatment infrastructure, and evaluate the cost of upgrading water systems globally.

WHO/UNICEF Joint Monitoring Programme analysis, USGS contaminant database cross-referenced with national water authority reports from 80 countries. Treatment plant capacity modeling using EPA methodologies. Cost curve analysis for different contaminant removal technologies.

2 billion people currently lack access to safely managed drinking water. An estimated 2 billion more have access to water that is microbially safe but contaminated with 'emerging' pollutants: PFOA and PFOS (used in manufacturing), microplastics (from industrial processes and consumer products), and pharmaceutical residues (from wastewater treatment inadequacy).

Most treatment plants in low-income countries were designed in the 1960s-1980s and cannot remove these contaminants. Upgrading treatment to remove emerging pollutants costs $2,000-5,000 per household in wealthy countries; the same technology scaled to low-income countries would cost $200-500 per household but requires upfront capital LMICs cannot access.

4 million children annually.