Document Type


Date of Award



College of Science, Engineering, and Technology (COSET)

Degree Name

MS in Environmental Toxicology

First Advisor

Professor Mahmoud Saleh


This study was carried out to measure carbon tetrachloride and total trihalomethane (TTHM) levels in Houston's drinking water and compare them to the National Primary Drinking Water Standards for total trihalomethanes. Samples were collected from the faucets of several homes in various geographic locations throughout the city. Total trihalomethanes analyzed were: bromoform, chloroform, dibromochloromethane, bromodichloromethane, in addition to volatile compounds. Compounds were identified using a Gas Chromatography/Electron Capture Detector (GC/ECD), and confirmed by use of a Gas ChromatographyiMass Spectrometer (GC/MS). The data from the GC/ECD showed that total trihalomethane levels were at, or below national standard levels for most of the samples that were collected outside of the Beltway. Samples taken within the Beltway showed total trihalomethane levels slightly x above national standards. The quantitative measurements and geographical distribution of total trihalomethanes, as well as levels of each individual component are presented in this study.