We review sampling and analytical considerations for water sampling of less hydrophobic or hydrophilic POPs to identify and to recommend the best approaches, particularly for assessment of spatial and temporal trends on a global scale.
¡°Active¡± and ¡°passive¡± methods are available for sampling water for hydrophilic POPs, but no single approach can be recommended. We recommend a performance-based approach, in which sampling and quantitative analysis are needed so that future global trends of hydrophilic POPs can be monitored.