The Genesee County Health Department in Michigan has begun examining how the Flint water crisis may have affected the county’s infant mortality rate.

The county’s health department began its assessment over a year ago because officials knew that lead can negatively impact health. “We wanted to see if there were any implications,” says Mark Valacak, a health officer with the agency.

Though the state gathers data on infant mortality rate every year, Valacak wanted the county to conduct a more complete analysis given the lead contamination in Flint, so he asked the state epidemiologist to take a closer look. They have not noticed much difference in trends, but a more statistically significant sample will come between the end of this year and 2019, as trends should be examined over three- to five-year spans, Valacak said.

The Centers for Disease Control and Prevention categorizes pregnant women as an “at-risk population” for lead poisoning. Too much lead in a pregnant person’s body can cause miscarriage and premature birth, as well as impact the fetus’ brain, kidneys and nervous system. Similar to what lead can do to young children, exposure while in the womb can cause learning or behavior issues in the future.

Unsurprisingly, Genesee County Health Department Medical Director Gary Johnson said that one of the major causes of infant mortality is being born premature, among other things like unsafe sleeping positions and poor nutrition. The CDC confirms that premature delivery is the most common cause of infant mortality; it is to blame for more than one third of all infant deaths. And Genesee County sees the most number of preterm births in the state. Flint tops the city list, too.

Genesee County suffers from the state’s second highest infant mortality rates. In 2015, it was roughly nine per 1,000 live births. Forty-three babies died in the county before the age of 1 in 2015. The county’s five-year average is a bit lower at roughly eight deaths per 1,000 live births. The state average infant mortality rate, to compare, is roughly seven.

Flint’s rate jumps to 10.7 for the average of 2013-2015, according to a press release the county issued June 22. In 2015, it was 13.7, according to data the county analyzed. Of cities in the state, Flint, with a population of nearly 100,000, ranks in the top five highest for infant mortality rates.

When looking at the rate for Black people in the county specifically, the number increases to 15.6 for 2013-2015. In Flint, it was 14.7 and just 4.9 for White community members. This disparity is true across the country: Black infants face mortality rates 2.4 times higher than White infants.

Researchers are unclear why Black mothers face this possibility more than other moms. Some have placed the blame on the mothers’ eating habits or lifestyle choices like smoking or drinking, as this story published in The Nation earlier this year explains. 

But some believe greater forces—like racism—are at play.

The Nation elaborates:

Now, a growing body of evidence points to racial discrimination, rather than race itself, as the dominant factor in explaining why so many black babies are dying. The research suggests that what happens outside a woman’s body—not just during the nine months of pregnancy—can profoundly affect the biology within. One study found that black women living in poorer neighborhoods were more likely to have low-birth-weight infants regardless of their own socioeconomic status. More segregated cities have greater black/white infant-mortality disparities; women whose babies are born severely underweight are more likely to report experiences of discrimination.

The county assessment will be completed in September, but the county plans to continue doing deeper analyses on maternal and child health annually, Valacak says. This year’s analysis is the first of more to come.