The US Food and Drug Administration (FDA) rejected 1,763 food shipments from India, 1,480 from Mexico and 1,368 from China in the 12-month period ending in June this year.
Some of India's spices, seeds and shrimp contained salmonella while Mexico's seafood, chillies and cheese were found too filthy to eat. Chinese products like seafood, bean curd and noodles were also filthy, The New York Times has reported.
But the FDA did not reveal the quantity of the products turned back, making it impossible to determine whether it was just a box of produce or an entire shipload, the Times pointed out.
While China is hammered for defective food exports to the US, government records showed that food products from India and Mexico have been rejected more often than those from China.
Coming after China were the Dominican Republic, Denmark, Vietnam, Japan, Italy and Indonesia, all of them for shipping contaminated or mislabelled food products.
A total of 543 shipments were rejected from Denmark and 482 from Italy, the only two European countries among the nine countries with the most number of rejected shipments.
In the cases of Italy, Denmark and Japan, problems with labels or documentation were cited as the main offences.
China sent more products, including foods, to the US than any of these countries, in terms of dollar value. China shipped goods worth a total 288 billion dollars to the US in 2006, compared with Mexico's 198 billion dollars, India's 22 billion dollars and the Dominican Republic's 5.3 billion dollars.
Toothpaste made in China caused more than 100 deaths in Panama in recent months and the news started a chain reaction reaching the Beijing government, which this week executed its top official food and drug regulator, Zheng Xiaoyu, for taking bribes to approve untested medicine.
China in consequence has prohibited its manufacturers from making toothpaste with diethylene glycol, a poisonous industrial solvent that had been found in countless toothpaste tubes sent to many countries around the world. Toothpaste usually contains glycerine, a safe product, but it is more expensive than diethylene glycol, the poison used as a substitute.