The first clue as to how the human bomb was made comes from Bishop, who recreates the substance from the remains of the first human bomb and tests it on a watermelon. When he sets his radio transmitter to 331.6 megahertz, the melon blows, "like proximity fuses in World War II aerial bombs," Bishop says. Bishop's reference to proximity fuses is, remarkably, on target. During World War II, radio-wave proximity fuses were created in the Johns Hopkins University Applied Physics Laboratory. Radar attached to the bomb sent out pulses of radio waves--at about 180 to 220 MHz--that were reflected when they interacted with the target, usually warplanes, causing the bomb to detonate. According to the Naval History and Heritage Command website, "The interference it creates with the transmitter results in a low-frequency beat caused by the combination of the transmitted and the reflected frequencies. The low-frequency signal can be used to trigger an electronic switch."
The idea that the Colonel's radiowave device acted as a trigger to the serum by sending out a low-frequency radio wave is less believable. In order for the serum to be triggered by such waves, they would have to be able to receive the signals and trigger an explosion. For the World War II-era proximity fuses, the trigger would likely have been a thyratron, a gas-filled tube that is a high-energy electrical switch. The only way to inject such a trigger into the body would be--and we're guessing here--multiple nano-sized thyratrons. To the best of PM's knowledge, these do not exist.
But even less believable than tiny, complex trigger devices is that the body would retain the fuel that turned these people into walking bombs. "For these people to have been injected with a substance that is capable of exploding and bioaccumulates in all of their tissues to a concentration that allows said explosion to occur does not seem possible," says toxocologist Allan Mottram.
"When we talk about how the body handles chemicals and other foreign substances we tend to refer to the substances as xenobiotics," Mottram says. Xenobiotics encompass all foreign substances that enter the body, whether they're synthetic or biological, or wanted or not. "It is clear from the story that the xenobiotic was distributed to all of [the patients'] tissues considering that all of their cells solidified and exploded," Mottram says.
But in real life, that wouldn't be possible. "Elimination starts as soon as the xenobiotic is absorbed," Mottram says. "It occurs primarily through the kidney, but also via the gastrointestinal tract, lung and skin." Xenobiotics may also undergo transformational reactions in the liver. "Phase I reactions [are] typically a detoxifying process but sometimes nontoxic xenobiotics are converted to toxic ones," Mottram says. "Phase II reactions involve making the molecule more hydrophilic [soluble in water]," he says. "This helps them to be cleared by the kidney."
"Such a massive body burden of this theoretical molecule does not seem tolerable," he says. "I would imagine that these people would be gravely ill, if not dead."
But, Mottram says, that doesn't mean that bioaccumulation doesn't occur. In fact, it happens quite often--and usually "with significant adverse effects," he says. Take nitroglycerin, for example. When this drug is administered to patients who are having a heart attack, mitochondria in the body convert the glycerol trinitrate to nitric oxide very rapidly. "We give someone a tablet [or administer the nitroglycerin intravenously], it dissolves, produces nitric acid and dilates blood vessels, allowing blood to flow," says Mottram. The result is a quick drop in blood pressure--but no explosion.
"There's not a whole lot of talk about why it is that pure liquid nitroglycerin is explosive and why medicinal glycerol is not," says Mottram. "It's explosive because it has a carbon backbone and oxidizing agent built into it. You shake it [and activate these] and it explodes."
But medicinal trinitrate isn't explosive, because it's diluted. "Let's say someone has a syringe of pure nitrate--that could explode," Mottram says. "But if you inject it into the vein, it will be diluted pretty rapidly, and then the oxidizing source is not near the carbon backbone," he says. "You could pump enough 100 percent nitroglycerin into a body to such that it would explode, but the person would have died long before you got to that point for a variety of reasons."
Even if the serum in Fringe was nitroglycerin, "another criticism is that the body promptly metabolizes nitroglycerin to nitric oxide," Mottram says. "Thus, there is no bioaccumulation. The concentration of nitroglycerin that is explosive 100 percent, or 100 grams per 100 milliliters, is not tolerated by the human body. We use max concentrations of 5milligrams per 1 milliliter therapeutically."
The Advent of the Proximity Fuse