In a statement posted on its website on Wednesday, the provincial quality watchdog said there is no evidence that the plasticizer was intentionally added to the liquor.

The provincial administration submitted the investigation results to the central quality watchdog, the General Administration of Quality, Inspection and Quarantine.

It also urged the company to determine the sources of the plasticizer and carry out a thorough overhaul of its products.

The provincial administration said it would continue with its investigation and severely deal with any illegal acts.

A major liquor company in Hunan, Jiugui Liquor defended itself on Monday night, saying it did not add the plasticizer in its production process and was checking the tests, according to the news article on www.21cbh.com.

Jiugui Liquor shares on the Shenzhen exchange market have been suspended since Monday, and the news report also caused a sharp drop in the share prices of many other major domestic liquor producers on Monday.

Jiugui liquor products had been taken off some supermarket shelves by Wednesday.

According to experts, plasticizers are used to thicken liquids, but alcohol products do not need this. The chemicals can cause male reproductive issues as well as damage the digestive and immune systems.

Liu Xuejun, a food science professor at Jilin Agricultural University, told Xinhua there was little possibility of intentionally adding plasticizers to alcohol products.

Liu mentioned two possible causes of excessive levels of plasticizers in liquor products. The chemicals may leak from PVC tubes or vessels used for storage or transportation, or they may come from flavoring essences used in liquor.

The China Alcoholic Drinks Association said on Monday large-scale tests on China's liquor products show that almost all alcohol products contain plasticizers, with an average level of 0.537 mg/kg. High-end liquor products contain more plasticizers than low-end ones.

Domestic levels of plasticizers in liquor products were below overseas standards, it said.

The association said the alcohol industry was discussing the limits for allowed levels of plasticizers in liquors.

A wider probe into the country's distilled spirits market has found trace amounts of DEHP, mainly DBP, in some other domestic liquor products, according to Xinhua's interview on Wednesday with officials from AQSIQ, MOH, and the China National Center for Food Safety Risk Assessment.