Scientists Thought Parkinson’s Was in Our Genes. It Might Be in the Water

Amy Lindberg settled quickly into life at Lejeune. She played tennis and ran on her lunch breaks, flitting through sprinklers in the turgid Carolina summers. But something dark was lurking beneath her feet.

Sometime before 1953, a massive plume of trichlorethylene, or TCE, had entered the groundwater beneath Camp Lejeune. TCE is a highly effective solvent—one of those midcentury wonder chemicals—that vaporizes quickly and dissolves whatever grease it touches. The spill’s source is debated, but grunts on base used TCE to maintain machinery, and the dry cleaner sprayed it on dress blues. It was ubiquitous at Lejeune and all over America.

And TCE appeared benign, too—you could rub it on your hands or huff its fumes and feel no immediate effects. It plays a longer game. For approximately 35 years, Marines and sailors who lived at Lejeune unknowingly breathed in vaporized TCE whenever they turned on their tap. The Navy, which oversees the Marine Corps, first denied the toxic plume’s existence, then refused to admit it could affect Marines’ health. But as Lejeune’s vets aged, cancers and unexplained illness began stalking them at staggering rates. Marines stationed on base had a 35 percent higher risk of developing kidney cancer, a 47 percent higher risk of Hodgkin’s lymphoma, a 68 percent higher risk of multiple myeloma. At the local cemetery, the section reserved for infants had to be expanded.

Meanwhile, Langston had spent the remainder of the 1980s setting up the California Parkinson’s Foundation (later renamed the Parkinson’s Institute), a lab and treatment facility equipped with everything needed to finally reveal the cause of the disease. “We thought we were going to solve it,” Langston told me. Researchers affiliated with the institute created the first animal model for Parkinson’s, identified a pesticide called Paraquat as a near chemical match to MPTP, and proved that farm workers who sprayed Paraquat developed Parkinson’s at exceedingly high rates. Then they showed that identical twins developed Parkinson’s at the same rate as fraternal twins—something that wouldn’t make sense if the disease were purely genetic, since identical twins share DNA and fraternal twins do not. They even noted TCE as a potential cause of the disease, Langston says. Each revelation, the team thought, represented another nail in the coffin of the genetic theory of Parkinson’s.

But there was a problem. The Human Genome Project had launched in 1990, promising to usher in a new era of personalized medicine. The project’s goal, to identify all of the genes in man, was radical, and by the time it was completed in 2000, frothy comparisons to the moon landing were frequent. Unraveling our genome would “revolutionize the diagnosis, prevention, and treatment of most, if not all, human diseases,” then president Bill Clinton said.

But for Langston and his colleagues, the Human Genome Project sucked the air out of the environmental health space. Genetics became the “800-pound gorilla,” as one scientist put it. “All the research dollars went toward genetics,” says Sam Goldman, who worked with Langston on the twin study. “It’s just a lot sexier than epidemiology. It’s the latest gadget, the bigger rocket.” A generation of young scientists were being trained to think of genetics and genomics as the default place to look for answers. “I characterize science as a bunch of 5-year-olds playing soccer,” says another researcher. “They all go where the ball is, running around the field in a herd.” And the ball was decidedly not environmental health. “Donors want a cure,” Langston says. “And they want it now.”