MX (3-Chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone) is a drinking water disinfection by-product (DBP). It is a potent mutagen and is of concern to public health. Data on MX levels in drinking water, especially in the UK, are limited. The aim of the present study is to investigate factors associated with variability of MX concentrations at the tap, and to evaluate if routinely measured trihalomethanes (THMs) are an appropriate proxy measure for MX. The authors conducted quarterly water sampling at consumers’ taps in eight water supply zones in and around Bradford, UK, between 2007 and 2010. 79 samples were collected, which were analysed for MX using GC-HRMS. Other parameters such as pH, temperature, UV-absorbance and free chlorine were measured concurrently, and total THMs were modelled from regulatory monitoring data. To our knowledge this is the longest MX measurement survey undertaken to date. Concentrations of MX varied between 8.9 and 45.5 ng/L with a median of 21.3 ng/L. MX demonstrated clear seasonality with concentrations peaking in late summer/early fall. Multivariate regression showed that MX levels were associated with total trihalomethanes, UV-absorbance and pH. However, the relationship between TTHM and MX may not be sufficiently consistent across time and location for TTHM to be used as a proxy measure for MX in exposure assessment.
Authors: Smith RB, Bennett JE, Rantakokko P, Martinez D, Nieuwenhuijsen MJ, Toledano MB. ;Full Source: Environmental Science & Technology. 2015 Jun 2;49(11):6485-93. doi: 10.1021/es5062006. Epub 2015 May 18. ;