HOUSTON -

You shop. You buy. You eat. Chances are you may not pay attention to where all that food comes from. But now, some experts say not knowing the origins of your food could be putting your health at risk.

"What is the price of cheap food?" said Aleda Roth, a professor of supply chain management at Clemson University. "I realized we potentially have a ticking time bomb on our hands."

For eight years Roth has traced the origins of the food we buy -- the countries where the actual ingredients were grown. She said she found the same trend in every study.

"I found more and more ingredients were coming from China," Roth said.

She's talking about fruits, vegetables, fish and many other ingredients grown in Chinese fields and raised in Chinese waters. Roth said that could expose all of us to the pollution and industrial waste in China. She points to arsenic found in apple juice and lead discovered in rice that both came from China.

Roth said potentially dangerous toxic elements could taint the foods we eat and less than 2 percent of the imported food is tested for anything before it makes it to our store shelves.

"It may be that there are some parts of China that are not polluted, but we don't know," said Roth. "Why are we playing Russian roulette with our health?"

By checking labels, you can find some name-brand packaged foods like peaches, pears oranges and all types of frozen vegetables labeled "Product of China."  You can also find some fish, shrimp and other seafood from China - even some organic products were actually grown and shipped from China.

"I had no idea," said mom Emily Pruiett. "Being organic, that's how they water it and fertilize it. Who's over there making sure that it's organic in China?"

Food labels don't always tell the whole story. While federal laws require manufacturers to label the country of origin on fresh and frozen fruits and vegetables, those labels are not required for processed products or most other food we buy. Don't let just an American flag on the package fool you.

"If it said it's made in the United States, it doesn't matter," Roth explained. "They could get their ingredients from any place."

For example, on a box of processed frozen fried shrimp by SeaPak, while the American flag on the label said "Processed in the USA," the company's website reveals as much as 25 percent of the shrimp used in the product could actually be raised in China or three other Asian countries.

In Roth's study, she took 1,000 random food products and contacted each company to determine where the ingredients actually originated. She said only a handful of companies would even tell her.

"Why are companies not being transparent?" Roth asked. "Don't people have a right to know what's going into their bodies?"

To tell where a food product comes from on the foods you buy, look for a "Product of" statement on the label. A label that reads "processed" or "made" in the USA doesn't mean the same as "Product of USA."