China has stepped up scrutiny of milk production, tightening dairy controls and threatened to ?out? offenders amid a widening health scandal, state media said recently.

At least four Chinese infants have died and thousands have been treated in hospital after drinking toxic milk and milk formula that has led to Chinese-made products being pulled off shelves around the world.

The formula was laced with the chemical melamine to cheat nutrition tests, the latest in a long line of Chinese food and product safety scandals involving items as diverse as fish, drugs, toys, toothpaste, tyres and petfood.

New dairy standards

?The regulations tighten control of how milk-yielding animals are bred, how raw milk is purchased and the production and sales of dairy food,? Xinhua news agency said. ?There will also be more severe punishment for people who violate safety standards and quality control departments that fail to fulfil duties ... Law-breaking producers will be blacklisted and outed publicly.?

Several local officials have already been sacked and 27 people have been arrested. More than 20 milk companies have already been named as offenders. ?Any non-food chemicals or hazardous substances are prohibited from being added into raw milk in its production, purchase, storage, transport and sale,? Xinhua said, citing the regulations issued last week by the State Council.

But the Health Ministry recently released new dairy standards and safety limits for melamine ? one milligram of melamine per kilogram for infant formula and 2.5 mg per kg for milk, milk powder and food products containing at least 15 % milk.

The US Food and Drug Administration said earlier this month that no amount of melamine was safe in baby formula.

OVER 100 SICK AFTER EATING DUCK AND DONKEY MEAT

Some 170 wedding banquet guests were rushed to hospital in north China when powdered rust remover was added to the pot instead of salt after they all decided it needed added flavour, Chinese media said.

In a bizarre coincidence, 61 wedding guests were taken to hospital with similar symptoms a day earlier after a duck-and-donkey-meat banquet in northwest China.

In the rust remover case, the bride?s proud father invited 170 friends and relatives to the wedding banquet at a village in northern Hebei province last Friday, the night before the nuptials, the ?Beijing News? said. ?All food was stewed in a big pot but after dinner started, all of them felt the taste was too bland,? the newspaper said.

Someone added what he or she thought was salt ? several times. An hour later, the guests were being rushed to hospital. ?When I arrived at the hospital, the observation room was packed with people vomiting, with stomach pains and with diarrhoea,? a doctor was quoted as saying. The symptoms were short-lived and all the victims were released by the next day.

A day earlier, 61 wedding guests suffered food poisoning at a banquet in impoverished Gansu province, local authorities said.

?Currently, 17 people have been discharged but 44 are still in the hospital. No one has died,? ?Xinhua? news agency quoted an official as saying.

Duck, donkey meat, chicken and shrimp were the main dishes served at the dinner.