Pediatrician Carla Nelson remembers catching sight of the unusually pale newborn, then hearing an abnormal heartbeat through the stethoscope and thinking that something was terribly wrong.

The baby was born minutes before with a severe heart malformation that would require complex surgery. What worried her as she waited for the ambulance plane to take the infant from Waimea, on the island of Kauai, to the main children’s hospital in Honolulu, on another Hawaiian island, was that it was the fourth one shehad seen in three years.

In all of Waimea, there have been at least nine in five years, she says, shaking her head. That’s more than 10 times the national rate, according to analysis by local doctors.

Nelson, a Californian, and other local doctors find themselves in the eye of a storm swirling for the past three years around the Hawaiian archipelago over whether a major cash crop on four of the six main islands, corn that’s been genetically modified to resist pesticides, is a source of prosperity, as the companies claim – or of birth defects and illnesses, as the doctors and many others suspect.

After four separate attempts to rein in the companies over the past two years all failed, an estimated 10,000 people marched on 9 August through Honolulu’s Waikiki tourist district. Some held signs like, “We Deserve the Right to Know: Stop Poisoning Paradise” and “Save Hawaii – Stop GMOs” (Genetically Modified Organisms), while others protested different issues.

“The turnout and the number of groups marching showed how many people are very frustrated with the situation,” says native Hawaiian activist Walter Ritte of the island of Molokai.