Pediatrician Carla Nelson ... waited for the ambulance plane to take the infant from Waimea, on the island of Kauai, to the main children's hospital in Honolulu. It was the fourth [severe heart malformation] she had seen in three years. There have been at least nine in five years, she says, shaking her head. That's more than 10 times the national rate. Corn that's been genetically modified to resist pesticides [is] a major cash crop on four of [Hawaii's] six main islands. In Kauai, chemical companies Dow, BASF, Syngenta and DuPont spray 17 times more pesticide per acre than on ordinary cornfields in the US mainland. About a fourth of the total are called Restricted Use Pesticides because of their harmfulness. Just in Kauai, 18 tons - mostly atrazine, paraquat (both banned in Europe) and chlorpyrifos - were applied in 2012. The World Health Organization this year announced that glyphosate, sold as Roundup, the most common of the non-restricted herbicides, is "probably carcinogenic in humans". When the spraying is underway ... residents complain of stinging eyes, headaches and vomiting. At these times, many crowd the waiting rooms of the town's main hospital, which was run until recently by Dow AgroSciences' former chief lobbyist in Honolulu. The chemical companies that grow the corn ... refuse to disclose with any precision which chemicals they use, where and in what amounts, but they insist the pesticides are safe. Today, about 90% of industrial GMO corn grown in the US was originally developed in Hawaii.