In an attempt to reassure the public on food safety standards a joint statement has been issued by the U.S. Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA) that the latest food scare over contaminated animal feed has not affected the human food supply.
The pet food is thought to have been contaminated by two chemicals, melamine and cyanuric acid.
On April 27 the FDA first suspected that meat from 345 pigs who had eaten the contaminated feed had entered the U.S. food supply.
Now the government agency is saying no human illness has occurred from exposure to melamine or its by-products and neither have they identified any illnesses in pigs fed the contaminated feed.
Thousands of pigs suspected of eating the contaminated product have since been quarantined and the FDA says meat from the animals will be withheld from the food supply.
Both the FDA and USDA say the likelihood of human illness from eating pork from pigs exposed to melamine is low because it was only part of the total feed given to the hogs and is not known to accumulate in pigs.
They also say pork plays only a small part in the average American diet.
The FDA believes the chemical melamine tainted rice protein used in the production of pet food and some of the pet food was used in animal feed.
This latest scare has resulted in the recall of over 100 dog and cat food products from the market.
The rice protein was imported to the U.S. from China and to date it is thought to have been used in contaminated pet food and given to pigs in California, Kansas, New York, North Carolina, South Carolina and Utah.
A pet food plant in Kansas has been searched by authorities in the on-going investigation.
The company Menu Foods makes more than 100 brands of pet food and uses wheat gluten supplied by ChemNutra, imported from China, which has been found to be contaminated with the chemical melamine.
There are also suspicions that some of the contaminated pet food scraps may have been used in poultry feed produced Missouri which are still being investigated.
The scare was initiated by the Canadian Menu Foods company which first found Melamine in it's pet foods which were immediately recalled on March 16th.
The initial recall included moist dog and cat foods made with melamine-contaminated wheat gluten imported from China but that has since expanded to other pet food manufacturers and other pet food ingredients, including imported rice protein concentrate and corn gluten.
A new recall issued last week by Chenango Valley Pet Foods in New York concerns shipments of dry pet foods, including selected packets of: Doctors Foster & Smith Chicken & Brown Rice Formula Adult Lite Dog Food; Doctors Foster & Smith Chicken & Brown Rice Formula Adult Lite Cat Food; Lick Your Chops Lamb Meal, Rice & Egg Cat Food, and Bulk Chicken & Brown Rice Formula Adult Lite Dog Food.
Both melamine and cyanuric acid have apparently been used to boost the protein content of foods but cyanuric acid is most often used as a stabilizer in outdoor swimming pools and hot tubs.
An unknown number of dogs and cats have been sickened or died after eating the contaminated pet food.
This latest food scare is doing little to enhance the confidence of Americans regarding the safety or the labeling of any "food" ingredients imported from China or other developing countries.
The FDA has over recent years been harshly criticised by many for allowing lobbyists and the views of conservative politicians to influence it's policies and decisions.
But as cheap imported goods, much of it from China, floods markets across the U.S. the challenge to the FDA is immense.
China itself has no way of keeping track of food products with regard to how they were grown or who grows them or which chemicals and drugs are used and many foods are grown, processed, stored and transported by poor workers with little knowledge of food safety issues.
It is also suspected that some Chinese companies that buy, process and export products use misleading labels in order to justify higher prices.
The Chinese government too is not noted for it's transparency and claims it tries to keep food safe are often dubious with Chinese consumers themselves expressing skepticism as to the quality and safety of many of their food products.
China has now banned melamine from its food products and is said to be cooperating with U.S. authorities but China rejects claims that the substance caused the pet deaths.
Meanwhile the FDA is still attempting to get it's investigators into China.
China's Foreign Ministry has said in a statement that there was no evidence to support the FDA's claim but that it would cooperate with the United States to find out what actually killed the animals.