Health officials in Ho Chi Minh City have found tapioca balls containing bleach and microorganisms in a three-week inspection that ended Monday.

Beginning August 11, the HCMC Health Department took 16 tapioca ball samples from four milk tea shops, two tapioca ball traders and one manufacturer for testing after online reports from Chinese newspaper Renmin Wang last month said tapioca balls used in milk tea in China contained polymers, chlorides and sodium sulfates that were harmful to human health.

No polymer was detected in the HCMC tests but the department said four samples tested positive for microorganisms in amounts higher than permitted and six samples were found with sodium sulfate, which is banned in cooking products by the Ministry of Health as it functions as industrial bleach.

Tapioca balls, known as “pearls,” are used in popular milk tea drinks, a favorite of local teenagers and college students.

The department inspectors have halted operations at the producer and sellers and seized all the balls in the same batches with those contaminated.

A written request has also been sent to district governments to inspect all producers and sellers of the pearls across the city.

Inspectors in the southern hub suspended Long Phu Company in HCMC’s Tan Phu District on August 12 for producing the tapioca pearls without meeting food safety standards and using bleach as an ingredient.

Hanoi authority began similar inspections at the same time following the Chinese pearl information. They found no polymer either but samples containing more benzoic acid, sorbic acid and saccharine than permitted.

Reported by Thanh Tung