Average birth weights have decreased among infants born in Flint, Michigan, after the city’s shift from using the Detroit Water Authority to the Flint River for its tap water source, according to an analysis published in the Journal of Public Health Policy.
Researchers obtained birth weight data found in the 2005 to 2015 National Vital Statistics from the National Center for Health Statistics to examine the association between Flint’s newer tap water source and low birth weight (<2500 g). The investigators included data from various control counties for comparison.
Infants who were conceived within a 3-month period after the switch from the Detroit Water Authority to the Flint River water supply weighed approximately 50 g less than those in the control counties. In addition, researchers observed a 0.0153 increase in the incidence of low birth weight after the change to the new water supply. Among white mothers, there was a >2% reduction in the average birth weight and a 2.73% increase in low birth weight incidence.
According to the researchers, there was a great deal of variability in the incidence of low birth weight among infants born to black residents in Flint. The investigators suggest that the variability seen may be partially “driven by the more volatile socioeconomic conditions and violence in predominately black neighborhoods.” They add that not enough control data were available for black mothers to make reliable estimates.