The city of Flint, Michigan, has declared a state of emergency because of high levels of lead in children's blood, reports The Washington Post. Many, including the city's mayor, suspect that a change in the city's main water source in 2014 — a switch from the Detroit water system to Flint River — is to blame for illnesses among the city's children.

Flint "has experienced a Manmade disaster [sic]," Mayor Karen Weaver said in a statement on Monday. By declaring a state of emergency, she hopes the federal government will help the city deal with the "irreversible" effects of lead exposure.

Exposing children to lead puts them at risk of anemia, impairment of the kidneys, and toxicity to the reproductive organs. Lead can also affect a child's brain development, leading to antisocial behavior and a reduced IQ, according to the World Health Organization. It's unclear how many children in Flint are suffering from lead exposure, but a study published in September by Flint's Hurley Medical Center hints that this problem isn't going away. The proportion of children with above-average levels of lead in their blood almost doubled after the city switched its main water source, the researchers say.

For the people of Flint, the results of the study were devastating — but not unexpected. In January, the state informed Flint's residents that the city's water carries unlawful amounts of a chlorine byproduct that has been linked to diseases such as cancer. The notice also said that Flint's water was safe to drink, but that children, the elderly, and people who have a severely compromised immune system "may be at increased risk and should seek advice about drinking water from your health care provider."

For months, protests and a petition did nothing to change the city's water source. So, those who could afford it bought bottled water, while many others continued to drink from Flint River. In October, the city finally returned to the Detroit water system. A month later, a group of parents filed a class-action lawsuit against the city, the state, and a number of public officials. The lawsuit links health conditions such as hair loss, vision loss, and depression to the city's water.

"For more than 18 months, state and local government officials ignored irrefutable evidence that the water pumped from the Flint River exposed [city residents] to extreme toxicity," the lawsuit reads. "The deliberately false denials about the safety of the Flint River water was as deadly as it was arrogant."

Yesterday, FEMA sent 28,000 liters of bottled water to a food bank in Flint. A Virginia Tech researcher told Michigan Live earlier this month that despite the city's switch back to the Detroit water system, the water in some parts of the city is still unsafe to drink if left unfiltered.