Shanghai food and drug authority warned people not to eat youtiao (fried loaf) sold at street vendors as it contains higher-than-standard levels of aluminum, a local newspaper reported today.

All eight samples from the city's street vendors failed to meet the local food safety standard, and 11 out of the 18 samples from local restaurants were substandard, according to the test results of the Shanghai Food and Drug Administration yesterday.

Shanghai food and drug authority warned people not to eat youtiao (fried loaf) sold at street vendors as it contains higher-than-standard levels of aluminum. [Xinhua.net]

The four samples provided by local supermarkets were safe enough to eat, said the report.

The administration has set punishment to those that produce substandard youtiao, the report said.

Youtiao is a traditional breakfast for the people living in Shanghai. Youtiao, Doujiang (soybean milk), Cifan (rice dumpling with youtiao inside) and Dabing (sesame seed cake), are of the four favorite dim sum breakfasts of local citizens.

People add alum as an additive in the traditional cooking process of youtiao. Aluminum, the main ingredient of alum, can harm a human's immunity system, negatively impact metabolism and slow the assimilation of calcium and phosphorus.

Ingesting too much aluminum can also increase the chance of suffering from dementia or bone soft disease.