Socioeconomic vulnerability and access to community water fluoridation in Washington.

Background: The aim of the authors was to determine whether socioeconomic vulnerability is associated with community water fluoridation (CWF).

Methods: The authors used US Census Bureau data to create 4 county-level vulnerability markers (percentages non-White, Hispanic or Latino, below the federal poverty threshold, education below high school), obtained county-level CWF data from the Washington State Department of Health, and evaluated associations using Spearman rank correlation coefficient and the Kruskal-Wallis rank sum test. The authors then interviewed 122 community members in Washington (December 2022-March 2023) and analyzed the interview data inductively.

Results: A higher percentage of non-White people at the county level was associated with a significantly higher level of CWF (Spearman rank correlation coefficient, 0.55; 95% CI, 0.29 to 0.82; P < .001), whereas county-level poverty was associated with significantly lower CWF (Spearman rank correlation coefficient, -0.36; 95% CI, -0.70 to -0.03; P = .02). High school completion was not associated with county-level CWF. Significantly larger proportions of Hispanics and Latinos lived in counties with higher CWF (P < .05). From the interviews, more participants thought tap water was healthy than unhealthy, but 41% had mixed feelings. Similarly, more participants thought CWF was acceptable than unacceptable, with 35% reporting mixed feelings. Negative views about tap water and CWF were more common among non-White participants.

Conclusions: People in racially and ethnically diverse communities in Washington appear to have greater access to CWF, whereas those in lower-income communities have poorer access.

Practical Implications: CWF is an important population-level strategy to prevent caries. Additional work is needed to improve access to CWF, especially for people from low-income communities.