BACKGROUND By international standards, water supplies in Perth, Western Australia, contain high trihalomethane (THM) levels, particularly the brominated forms. Geographic variability in these levels provided an opportunity to examine cross-city spatial relationships between THM exposure and rates of birth defects (BDs). OBJECTIVES Our goal was to examine BD rates by exposure to THMs with a hi...

The purpose of the study was to determine whether the risk of childhood acute lymphoblastic leukemia (ALL) associated with drinking water disinfection by-products was modified in the presence of variants in genes involved in the metabolism of trihalomethanes (THMs). We included a subset of cases from a population-based case-control study in a case-only study to estimate the interaction odds rat...

This paper summarizes the epidemiological evidence for adverse health effects associated with disinfection by-products (DBPs) in drinking water and describes the potential mechanism of action. There appears to be good epidemiological evidence for a relationship between exposure to DBPs, as measured by trihalomethanes (THMs), in drinking water and bladder cancer, but the evidence for other cance...

Around the world, coastal groundwater is increasingly subject to seawater intrusion (SWI). The quality and characteristics of such waters differ from those surface groundwater. In current study, trihalomethane (THM) formation under varying levels SWI, natural organic matter (NOM), chloride-to-bromide (Cl/Br) ratio was evaluated. Different SWI were simulated by mixing deionized water with real (...

BACKGROUND AND AIMS Epidemiological studies of disinfection by-products (DBPs) and reproductive outcomes have been hampered by misclassification of exposure. In most epidemiological studies conducted to date, all persons living within the boundaries of a water distribution system have been assigned a common exposure value based on facility-wide averages of trihalomethane (THM) concentrations. S...

By studying the problem-solving techniques that people use to design algor i thms we can learn something about bui ld ing systems that automatical ly derive algor i thms or assist human designers. In this paper we present a model of a lgor i thm design based on our analysis of the protocols of two subjects designing three convex hull algori thms. The subjects work mainly in a data-f low problem...

We report the formation of trihalomethanes and other disinfection by-products from four polyfunctional terpenoids during simulated chlorination of natural waters. Complex suites of products were identified by closed loop stripping analysis (CLSA)/gas chromatography-mass spectrometry (GC-MS) from halogenation of beta-carotene and retinol. beta-Ionone appeared to be a key intermediate in the halo...

The existence of trihalomethanes (THMs) in a drinking water plant of Nicaragua has been investigated in order to see whether the concentration exceeded the maximum contaminant level recommended by the environmental protection agency of the United States (USEPA) and the Nicaragua guidelines. The influence of pH, temperature, chlorine dose and contact time on the formation of THMs were studied. T...