Melamine fears fueled by new revelations

First it was baby formula. Then, dairy products from yogurt to chocolate.

Now chicken eggs have been contaminated with melamine, and an admission by state-run media that the industrial chemical is regularly added to animal feed in China fueled fears Friday that the problem could be more widespread, affecting fish, meat and who knows what else.

Peter Dingle, a toxicity expert at Murdoch University in Perth, Australia, said, however, that aside from the tainted baby formula that killed at least four Chinese infants and left 54,000 children hospitalized just over a month ago, it is unlikely humans will get sick from melamine. The amount in a few servings of bacon, for instance, would simply be too low, he said.

But Dingle and others said China should have cracked down sooner on feed companies that boosted earnings by fortifying products with the chemical, which is normally used in plastic and fertilizers. Rich in nitrogen, melamine gives low-quality food and feed artificially high protein readings.

Extremely high levels of melamine – as found in the Chinese baby formula – can cause kidney stones, and in extreme cases can bring on life-threatening kidney failure.

Scientists say it's not dangerous to ingest small amounts, but can't be definitive because there have been no tests on melamine's effects in humans.

China has vowed to boost inspections for melamine, but it will be difficult to monitor the countless small, illegally operating manufacturers nationwide, other experts said.