Tracing sources of natural organic matter, trihalomethanes and metals in groundwater from a karst region.

Groundwater offers an important source for drinking water around the world; however, groundwater quality is under increasing pressure and is particularly vulnerable in karst areas. Total organic carbon (TOC) is significantly related to groundwater quality and when not removed by water treatment processes can give rise to the formation of disinfection by-products trihalomethanes (THMs) above the level of compliance. This study investigated the source of organic matter giving rise to the THM exceedances in a groundwater supply in a karst area.