Effects of Typical Household
Water Use Activities on Breath Chloroform Levels

Chloroform, an environmental pollutant, is the major disinfection by-product of drinking water treated with chlorine for domestic usage, and a long-standing health concern. Now classified by the U.S. EPA as a probable human carcinogen, chloroform once appeared in toothpastes, cough syrups, ointments, and other pharmaceuticals; it has been banned in consumer products in the United States since 1976. Exposure to chloroform can occur when breathing contaminated air or when drinking or coming in contact with water containing it. Common household activities such as showering, bathing, drinking water, and washing clothes and dishes can increase the likelihood of individual exposure to chloroform.

Battelle recently conducted a study with the Centers for Disease Control and Prevention (CDC) in which typical household water-use activities that were thought to lead to the greatest chloroform exposures were investigated. Participants performed a variety of common water-use activities in two residences served by water utilities with relatively high and low total chloroform levels. To maintain a consistent exposure environment, the activities, exposure time, air exchange rate, water flow and temperature, and extraneous chloroform emissions to the indoor air were carefully controlled. Water, air, and exhaled breath samples were collected during each exposure session for each activity that could potentially elevate the internal dose of chloroform. At the start of each exposure session, indoor air and exhaled breath samples were collected. Air samples were then collected during each individual activity while breath samples were collected five minutes after each activity.

Showering (for 10 minutes), bathing (for 20 minutes), and machine clothes washing activities caused significant increases in air and exhaled breath chloroform concentrations as a result of inhalation exposure and dermal contact. For the showering and bathing activities, strong correlations were observed among levels for breath and air, breath and water, and water and air. Despite the small study population, the association between specific activities and level of chloroform exposure was clearly demonstrated in this study.

For additional information, contact Dr. Sydney Gordon at (614) 424-5278, gordon@battelle.org.