There’s a scene in Close Encounters of the Third Kind where the Air Force subjects Richard Dreyfus and his fellow Third Encounterers to the media. The press conference is actually going pretty well, the media seem to be on the verge of believing these people—until one of them, a bearded old hermit type (Roberts Blossom) launches into a speech about how he once saw Bigfoot. Credibility: shot.

Such is the case, too, with people who’ve been trying to link celiac disease (and other ills) with the use of the herbicide glyphosate. Despite having long been treated like Bigfoot believers by their opponents, their research is now gaining widespread attention. More importantly, there's a growing sense that the science has reached a tipping point: Glyphosate cannot be recognized as harmless.

“I'm always suspicious of these consensuses on [the safety of] agriculture chemicals—they almost always fall apart over time, and that may be happening with glyphosate,” says author and food activist Michael Pollan.

Introduced by Monsanto in the early 1970s under the trade name Roundup (and used primarily back then as a weed killer), glyphosate is now used throughout the world on wheat and soy crops and since 2007 it has been the most widely used herbicide in the U.S.—and the growing target of research linking it to a variety of illnesses.

“Since Monsanto first introduced Roundup into crops in 1974, there’s been a rise in autism and other diseases,” says Stephanie Seneff, a senior research scientist at the MIT Computer Science and Artificial Intelligence Laboratory and co-author, with Anthony Samsel, a retired environmental scientist, of the recent review claiming that Roundup leads to celiac disease . “I’m certain at this point that glyphosate is the most important factor in an alarming number of epidemic diseases.” Diseases ranging from autism, Alzheimer’s, and diabetes to pancreatic cancer, thyroid cancer, non-Hodgkin’s lymphoma, Parkinson’s disease and—wait for it—the ongoing collapse of bee colonies.

But where then, beyond the work of Seneff and Samsel, is the proof? Well, there isn’t much hard evidence (only two long-term studies on the health effects of the chemical have been conducted). And for a complicated set of reasons. For one, historically, people who’ve challenged the biotech industry have been systematically discredited, says Pollan, "as we learned recently about Tyrone Hayes, the UC Berkeley herpetologist who ran afoul of Syngenta." Also, there’s the just-as-hard-to-prove theory that no one wants to bite the hand that feeds them.

“Some of our scientists are the ones who are the most difficult—and the biggest impediment to better research—because they’re funding is dependent on the very same agrichemical companies like Monsanto that are producing Roundup,” says Dr. Don Huber, professor emeritus of plant pathology at Purdue University (who for years consulted with Monsanto scientists). "They’re not about to go in a different direction from the people who’ve been funding them."

There are “absolutely potential adverse health effects from glyphosate,” says Hansen. But the strongest data is in cases of birth defects and non-Hodgkins lymphoma.

Others agree. Many of them levelheaded, despite coming off like Oliver Stone. “Monsanto and these other companies are doing an exceptionally good job at blocking all information and data on the subject from public discourse,” stresses Dave Schubert, professor and head of the Salk Institute’s Cellular Neurobiology Laboratory.

“There is indeed an enormous amount of published data showing that Roundup is very nasty stuff, particularly at the levels currently being used (ten times more than before genetically modified, herbicide-resistant crops) and the extent of human exposure in food—a greatly allowed increase by the EPA to reflect increased use.”

Not everyone, however, is so convinced—though many are still intrigued by a possible link. “Samsel and Seneff have produced a series of plausible hypotheses,” says Sheldon Krimsky, chairman of the Council for Responsible Genetics and Professor of Urban and Environmental Policy and Planning at Tufts University. “But that is all they are: hypotheses.”

Indeed, Krimsky himself, as sober as he remains in his reception to Samsel and Seneff’s study, cites a chapter from Earth Open Source’s 2012 paper, “GMO Myths and Truths,” in which, among many other things, glyphosate is called “toxic,” Roundup’s marketing campaign as a “safe” herbicide is “based on outdated and largely unpublished studies by manufacturers,” glyphosate’s acceptable daily intake level in the U.S. and Europe is “inaccurate and potentially dangerously high,” and “the added ingredients (adjuvants) in Roundup are themselves toxic and increase the toxicity of glyphosate by enabling it to penetrate human and animal cells more easily.”

If Bigfoot’s still a bit fuzzy, consider these words from Dr. Alessio Fasano, founder of Massachusetts General Hospital’s Center for Celiac Research, in a 2011 interview with the gluten-free website livingwithout.com: “Gluten and autism, gluten and schizophrenia—is there a link or not?” he asked rhetorically.“I have a hard time believing that gluten has absolutely nothing to do with these behaviors.”

Many, though, do. “There is no link between Roundup and celiac,” says Dr. Stefano Guandalini, founder and medical director of the University of Chicago’s Celiac Disease Center, in response to Samsel and Seneff’s review. “The whole story is preposterous and finds a cause/effect relationship when there is none.”

Other critics have been harsher, while supporters embrace the review as evidence of what’s been plaguing them and/or their children. Already an emotional issue, celiac disease is an autoimmune disorder of the small intestine that affects upwards of 3 million people in the U.S. alone. It is triggered by gluten, the protein in wheat, barley, and rye. As yet there is no cure.

Linking celiac disease to glyphosate also stems on the belief (and a growing body of scientific literature that seems to back it up) that glyphosate, and aminomethylphosphonic acid, or AMPA, the compound glyphosate breaks down into as it decays, affects the balance of our gut microbials. These changes to our bacteria can then lead to disease, obesity, autoimmune deficiencies—and maybe even the bee-colony collapse.

“You have this very broad, extremely powerful broad-spectrum chelator that causes a tremendous level of dysbiosis,” says Dr. Huber. “When you disrupt your intestinal microflora, you’re not a happy individual.” Or healthy.

Part of the reason it’s so easy to castigate Samsel and Seneff (and others like them) with the bigfoot brush is that, as they admit, many of their observations are anecdotal and their research is based on making correlations. Seneff graphed Roundup and its use in corn and soy and the rise of celiac disease (and other autoimmune disorders) and came up with A + B = C.

“People have been trained to dismiss these types of correlations, but they’re there,” asserts Seneff, a senior research scientist at MIT’s Computer Science and Artificial Intelligence Laboratory. “The data are there. You just have to connect the dots.” And the picture she has painted—glyphosate leading to celiac disease and a plethora of other maladies and autoimmune diseases—is far from pretty.

(Michael Hansen, a senior staff scientist with Consumers Union, denied that the dots match up so well. “If you don’t understand biology, you’d go, Wow! They match up perfectly. If you do understand biology, those graphs don’t show anything. They’re nonsense.”)

“They looked at the biochemical impact of glyphosate relative to the biochemical impact of various diseases and found a perfect fit—they didn’t have any problem connecting the biochemical dots,” explains Dr. Huber, who warns that our “wake-up call” is just around the corner.

In the meantime, while Samsel and Seneff’s review may not yet be fully accepted, their work, and others’, should lead to better, more convincing studies, something both Dr. Huber and Krimsky agreed is worth pursuing. And Hansen, who’s still leery of embracing any link to celiac disease, notes that there are “absolutely potential adverse health effects from glyphosate,” but that the strongest data is in cases of birth defects and non-Hodgkins lymphoma.

"There are growing suspicions that this supposed non-toxic pesticide is more toxic than we realized. Especially when used with the 'inert ingredients' it comes with—surfactants that help the chemical force its way into plant tissues," says Pollan. "There are also reports on illness around the big round-up soy fields in Brazil and Argentina. To me it seems like a lot of smoke and I wouldn’t be surprised to find fire.”

Until then, voices in the wilderness like Samsel and Seneff and Dr. Huber will continue to proselytize about the evils of their personal Bigfoot, and hope to prove Pollan right, and vindicate their theories. “The proof isn’t there,” says Seneff, “but the innuendo is.”