Detroit Free Press columnist Rochelle Riley recently noticed a startling fact about kids in the lead-poisoned city of Flint, Michigan: They have become increasingly bad at reading since the water crisis began in 2014. A state government report showed that, from the year 2014 to the year 2017, third-grade reading proficiency in the city dropped from 41.8 percent to 10.7 percent. “That’s nearly a three-quarters drop in third-grade reading proficiency among children whose lives were affected by lead poisoned water during the Flint water crisis,” she wrote.

Other factors were involved in this decline. The test changed to become more difficult in 2015, which led the third-grading reading proficiency statewide to fall from 70 to 44 percent. But Flint’s decline was much worse than the state’s average. Michigan Superintendent of Education Brian Whiston told Riley that this was “unacceptable,” and that some of the decline could be attributed to “stress.” Riley wasn’t having it. “What also isn’t acceptable is the state not putting into place three years ago a program to monitor and continually assess the development of the poisoned children,” she wrote.

Her outrage was shared by others. The Center for American Progress declared that Flint’s water crisis “has lead to a reading proficiency crisis,” while HuffPost reporter Alanna Vagianos tweeted that lead exposure in Flint was “having a significant developmental effect on children.” Their worry is grounded in the fact that, according to the CDC, lead exposure to children “can cause learning disabilities, behavioral problems, and, at very high levels, seizures, coma, and even death.”

I’ve lived near or in Flint most of my life. Pay attention



Flint third graders reading proficiency drops nearly three quarters in ONE YEAR.



Lead poisoning = learning disabilities. It’s happening. A GENERATION is screwed because of incompetence. https://t.co/ELoweHgfPc — Jonathan Diener (@jonodiener) February 9, 2018

Not everyone, however, was convinced that Flint’s water crisis had much to do with lower reading levels. Mother Jones columnist Kevin Drum, wrote that “a modest increase in lead ingestion simply shouldn’t have that big an effect.” Lead, he wrote, “primarily affects 1-5 year-olds. These are 8-year-olds. A smallish increase in lead levels simply wouldn’t have that big or that immediate an effect on 8-year-olds.” He added that if lead did cause the decline in reading proficiency, “then reading proficiency should have increased after 2016, when the lead was removed. It didn’t. It kept dropping, and so did scores throughout Michigan.”

Lead did not turn Flint children into idiots. Stop saying so. https://t.co/0JrtoKOSDJ (via @kdrum) pic.twitter.com/bOc4EIrVIA — Mother Jones (@MotherJones) February 9, 2018

But Drum’s analysis is based on a misunderstanding of how lead poisoning works, and the status of Flint’s water. Lead has not been “removed” from the city’s water system: State test results released Tuesday found that five out of nine schools in Flint had at least one test that exceeded the federal threshold for lead this year. In one elementary school, 14 of 93 tests registered lead levels of 15 parts per billion or more, and two sites registered more than 100 parts per billion. An Associated Press report last month showed that, in the waning months of 2017, four schools and care facilities in Flint had elevated levels of lead in their water.