Abstracts Health Sciences

Risk Perception, Drinking Water Source and Quality in a Low-Income Latino Community along the U.S.-Mexico Border

by Kerton Richard Victory

Previous studies have shown that low-income Latinos frequently drink bottled water instead of tap water and might be at increased risk for dental caries from unfluoridated bottled water. The goals of this study were to: 1) determine if a difference exists between grab samples of municipal tap water and bottled water used by families in Nogales, Arizona in chemical and microbial contaminants; 2) understand the risk perceptions these low-income families have about both their publically supplied tap water, bottled/vended water; and 3) examine whether families have adequate fluoride levels in their drinking water for optimal dental health. Tap and bottled water samples were collected from thirty of these households for analysis of drinking-water contaminants regulated by the U.S. Environmental Protection Agency (USEPA). Bottled water included small (0.5 L) and large (3.8 L), individually sealed water bottles as well as water vended into reusable containers from self-service vending machines or from water stores. Some of the large bottles were purchased sealed, but had been previously opened and partially consumed by study participants. In addition to the 30 households mentioned above, an additional sixty low-income Latino households, who primarily drink bottled water, were also recruited for this study to complete a questionnaire on risk perceptions related to drinking water consumption, water storage practices, and fluoride supplementation. There were no significant differences in the concentration of chemical contaminants between tap, bottled and vended water, and none of the chemical concentrations exceeded USEPA regulations. Escherichia coli (E. coli) was confirmed in 3% (1/30) of tap, 0% (0/8) of sealed bottled, 40% (2/5) of previously opened bottled, and 35% (6/17) of vended water samples. One of the 3 samples collected directly from a vending machine had an E. coli concentration of 0.33 CFU/100 mL. None of the 10 samples collected directly from sealed bottles purchased directly from the store had any E. coli detected. While no significant differences were observed in the chemical quality of water samples, results suggest that secondary contamination in the home contributes to higher levels of E.coli in water from partially consumed larger water bottles or water stored in reusable containers. Families who reported cleaning large reusable water containers with soap or hot water had significantly lower E.coli (p=0.003) in their drinking water than those who rinsed with only water. Respondents viewed bottled water to be significantly safer to consume than tap water (p<0.001). On a Likert scale from 1 (low risk) to 5 (high risk), "drinking tap water in Nogales, Arizona" received an average score of 4.7, which was significantly higher than the average perceived risk of smoking (µ= 3.5, p<0.001) or of "drinking tap water in San Francisco, California" (µ= 3.4, p<0.001), and as risky as "drinking and driving" (µ= 4.8, p=1.00) and "drinking tap water in Nogales, Sonora, Mexico" (µ= 4.8, p=1.00). Additionally, 98% (88/90)…