Disinfection by products (DBPs) in treated well water sources

Abstract

The study was about the formation of trihalomethanes (THMs) and haloacetic acids (HAAs) in drinking water. The raw water samples were collected from bore well in Felda Chuping, Semadong, Arau and Timah Tasoh, Perlis. The water samples were analyzed by gas chromatography-mass spectrometer (GC-MS). The range of concentration of THMs were TCM (0.001 to 0.181 mg/L), BDCM (0.001 to 0.024 mg/L), DBCM (0.001 to 0.016 mg/L) and TBM (0.001 to 0.025 mg/L). While the range of concentration of HAAs were MCAA (0.212 to 0.284 mg/L), DCAA (0.415 to 0.623 mg/L), TCAA (0.059 to 0.666 mg/L) and DBAA (0.805 to 0.8176 mg/L). The concentration of THMs in Perlis was below the maximum contaminant levels by World Health Organization (WHO) standards meanwhile, the concentration of HAAs in Perlis was higher than the maximum contaminant levels by World Health Organization (WHO) standards. BDCM (1.77×10-6 to 2.80×10-4) was posed the highest cancer risk in concentration of THMs in distribution system. While only DCAA (5.93×10-4 to 9.06×10-4) was detected in concentration of HAAs. According to the results, the average total lifetime cancer for BDCM and DCAA also higher than the general guidance risk value which is 1.00×10-6 was suggested by EPA standards. Therefore, the monitoring of levels of THMs must be conducted to loss the cancer risk on human health.