Water flowing from a handful of drinking fountains at two Boston public schools contained unsafe levels of lead, renewing concern about the city’s efforts to return tap water to buildings that now largely rely on bottles.

Three fountains at Thomas J. Kenny Elementary School in Dorchester and one fountain at Rafael Hernandez K-8 School in Roxbury tested above the state environmental protection department’s recommended lead level of 15 parts per billion, Boston Public Schools said Sunday.

Parents of students at both schools were notified by phone last week and also received e-mail notices that included suggestions about how to get children tested for elevated lead levels.

The affected water fountains were shut off, along with one other at Kenny Elementary because the water pressure was too low to test. With all four of its fountains shut off, Kenny joined the long list of city schools that rely solely on bottled drinking water, according to school system spokesman Dan O’Brien.

The Hernandez fountain that failed the test, now deactivated, showed a lead level more than double the safety standard. Other fountains at the school remain in operation.

The findings come as the school system conducts tests of 38 schools where children now gulp tap water from fountains that line the halls.

That effort gained renewed urgency in the wake of the lead crisis in Flint, Mich., where city water from some sources contained lead at hundreds of times what is considered safe for drinking.

In a statement e-mailed to the Globe on Sunday, Boston Public Schools said Hernandez and Kenny were among 26 schools where annual tests are complete. Though testing at the remaining 12 schools where fountains are still active has concluded, results have not been finalized.

At Kenny, the lead levels were slightly above the state standard for safety, but mostly fell below the slightly higher recommended US Environmental Protection Agency level of 20 parts per billion. The three fountains tested at 18, 27 and 17 parts per billion before being flushed for 30 seconds; after, they tested at 14, 15 and 20.

Diana Peck, a parent of two Kenny kindergarten students, said the news provokes concern. “As any parent would be when you hear of lead in the water, it is alarming,’’ said Peck, who expressed confidence in the school’s principal.

The fountain at Hernandez initially tested at 32 parts per billion; after the 30-second flush, it dropped to 5.1.

The other five fountains at Hernandez all tested at 11 parts per billion or below and were left in service, suggesting the single high reading stemmed from a problem with the particular fountain rather than the water supply.

It was not immediately clear when the affected fountains were last tested. A 2015 test at Kenny measured safe lead levels from a faucet; a 2013 test at a Hernandez fountain was also well below dangerous levels, though it was unclear which fountain was tested.

“In the past, when the issue of lead in the public drinking water supply became a national health concern, BPS switched to bottled water across all schools,’’ the statement read.

That plan, however, proved to be pricey: The city spent more than $400,000 on water and cups in the 2013-14 school year, up from about $270,000 five years before.

The district planned to upgrade plumbing in its schools to restore fountains.

Exposure to lead has been linked to IQ deficits and behavioral problems.

An e-mail sent to parents at Hernandez advised parents who are concerned to see their doctors about lead level testing and to seek “3-4 consecutive tests, as elevated lead levels can be caused by a variety of environmental factors and their risks are better assessed through a series of testing.’’

Wayne Thomas, the parent of a first-grader at that school, said he thinks he will test the child but is waiting to see what the school will do next. He worries that some parents may not be able to afford such tests.

“There’s not a lot of information yet, and that’s been frustrating for myself and other parents,’’ he said.

Jeremy C. Fox and Matt Rocheleau of the Globe staff contributed to this report. Nestor Ramos can be reached at nestor.ramos@globe.com.