Police have arrested eight people, including a kindergarten owner and investor, after 233 children suffered lead poisoning from contaminated food at a kindergarten in northwest China's Gansu Province, officials announced Tuesday.

The mass poisoning at Heshi Peixin Kindergarten in Tianshui City occurred when kitchen staff used color paint – clearly marked as inedible – to color children's snacks, investigators said. Testing revealed two food items contained lead concentrations more than 2,000 times above safety limits: a date cake measuring 1,052 mg/kg and a corn sausage roll at 1,340 mg/kg, compared to China's 0.5 mg/kg standard.

Authorities identified the suspects as the kindergarten owner, surnamed Zhu, the investor, surnamed Li, and six staff members. Zhu and Li authorized kitchen staff to purchase non-edible paint online, which was diluted and used in food preparation.

On July 3, authorities seized the remaining paint that had been concealed. Lab tests confirmed the paint contained lead, with packaging clearly marked "not for food use."

Of 251 children tested, 233 showed elevated blood lead levels, with 201 currently hospitalized. Health authorities have provided free and individualized treatment while offering transfer assistance for families seeking specialized care elsewhere.

The privately run Heshi Peixin Kindergarten, which opened in 2022 and enrolled 251 children, remains closed as the investigation continues. Three other kindergartens also invested in by Li showed no contamination.

Tianshui authorities pledged comprehensive medical care for the affected children until full recovery, vowing long-term health monitoring for all victims.

The Gansu Provincial Commission for Discipline Inspection has launched an accountability investigation into the incident, vowing to punish those found responsible.

Lead poisoning can cause devastating and often irreversible health impacts in children, including severe neurological damage, developmental delays, learning disabilities, and reduced IQ levels.