BEIJING -- Bottled water producer Nongfu Spring Co has found itself in trouble, as recent reports indicate that its quality criteria fall short of those set by the government for the country's tap water.

Ma Jinya, secretary-general of the China National Health Association Drinking Water Committee, was quoted Friday by the Beijing Times as saying that the criteria Nongfu Spring uses are looser than national tap water standards in terms of the amount of arsenic and cadmium allowed in the company's products.

Nongfu Spring uses criteria that were set by the government of east China's Zhejiang province in 2005. National standards were upgraded in 2007, but the manufacturer has yet to update its own quality benchmarks accordingly.

The Zhejiang provincial government standards permit more than five times the amount of arsenic that the national standards allow.

The Zhejiang-based company insisted that its quality standards are higher than the national standards, adding that the scandal was set in motion by the company's rivals.

"We have reason to believe that recent reports targeting Nongfu Spring were created by C'estbon Food & Beverage (Shenzhen) Co Ltd, " the company said in a statement posted on its official microblog account on Sina Weibo, the Chinese equivalent of Twitter.

An investigation by Xinhua found that Nongfu Spring was the only drinking water company to participate in drafting the Zhejiang provincial standards.

C'estbon Food & Beverage denied the charges from Nongfu Spring, saying it has never taken any kind of malicious action against the company.

C'estbon said the accusations are intended to divert public attention away from Nongfu, adding that it has reserved the right to take legal action.

In November 2009, the Bureau of Industry and Commerce in the city of Haikou in south China's Hainan province issued a warning regarding Nongfu Spring's 30-percent mixed vegetable and fruit juice, as well as its C-100 grapefruit juice, due to high arsenic content.

The charges against Nongfu Spring were later cleared by the national consumer quality watchdog.

Analysts said the scandal underscores the challenges facing China's food and drinking water safety, as the country has "too many" rather than "too few" criteria concerning food safety.

Chen Junshi, an analyst with the China National Center for Food Safety Risk Assessment, said enterprises are only allowed to adopt local standards in exceptional cases when there are no relevant national standards. Exceptions are also made for companies operating under unique regional conditions that are considerably different from elsewhere in the country.

"Nongfu Spring's products do not meet the requirements for such an exception," Chen said.

China has formulated nearly 5,000 compulsory food safety criteria due to its excessive number of government departments, according to Wang Guojun, a member of the Committee of Experts of the China Food Industry Association.

Wang said the government should clean up the criteria and adopt new standards with the broad participation of enterprises, industrial associations, experts and the public.

"In fact, the current controversy over the criteria is all about interests," Wang said, "if the government fails to voluntarily upgrade industrial standards, enterprises will stay silent over cost concerns."

"The revision of such criteria, if there is any revision, should not be manipulated by large enterprises," Wang added.