Dr. Stone follows protagonist Senku Ishigami in a primitive world 3700 years into the future. Thanks to his superhuman knowledge of principles, processes and scientific elements; Senku is capable of producing modern wonders in an incipient world.
Although the artist Boichi has a degree in physics, the writer Riichiro Inagaki does not seem to have a degree in science. Instead, the team relies on an unnamed scientific advisor, as mentioned in multiple interviews.
In Dr. Stone, the most dangerous obstacle in the way of sulfonamides was the acquisition of sulfur in a world of stone. The harmful gases created by sulfur sinks, namely hydrogen sulfide and sulfur dioxide, are extremely toxic. Sufficiently high concentrations of hydrogen sulfide are found near the sulfur pools to cause almost instant death if inhaled. Fortunately, Senku managed to create two countermeasures to combat the gas; a silver spear and a gas mask.
The silver spear was integral to the survival of the Science Kingdom, as it allowed Ginro to detect the presence of hydrogen sulfide. Whenever silver comes in contact with hydrogen sulfide, it creates a thin black layer called black silver sulfide. Using this, the team is able to detect the presence of toxic gases without the immediate need for a gas mask.
The reason the group didn’t need a gas mask to find the location of the sulfur pool was due to the weight of the toxic gases. Hydrogen sulfide and sulfur dioxide are heavier than air, resulting in the gases being pushed to the surface while there is enough air around to compress it. As a result, the gases are particularly concentrated in cavernous depressions and craters.
Senku discusses an anecdote to give an idea of the danger while explaining that in his day there was a research group that once went to a sulfuric acid pit. The lead researcher in front knelt for a moment, speculated that maybe he was tying his shoes, and died instantly in that position.
There was a large concentration of hydrogen sulfide residing around her kneeling head height. Although Senku claims that “this really happened,” many on the Internet have searched for this story and have not been able to find it. This leads to the possibility that it may have been in a newspaper, but never properly archived.
To overcome the harmful gases, Senku managed to create gas masks for the expedition team. By carefully mixing activated carbon with potassium carbonate, you can create a makeshift gas mask filter to capture and neutralize deadly toxins in the air.
Oddly, there was a much simpler, more convenient, and safer method of obtaining sulfuric acid that Senku neglected. In 1600 Johann Glauber created sulfuric acid by burning sulfur together with saltpetre (potassium nitrate), in the presence of steam.
When saltpetre decomposes, it oxidizes sulfur to create sulfur trioxide, which combines with water to produce sulfuric acid. This would have avoided the danger of actively searching for a pool of uncontrolled sulfur and toxic gases as they already had all the other ingredients needed to follow Glauber’s experiment.
Regardless of the neglected method of obtaining sulfuric acid, the twelfth episode of Dr. Stone he is extraordinarily accurate in his depiction of the danger of sulfur pools. This is only indicative of the extraordinary quality and hard work that went into directing, drawing and writing Dr. Stone.
Dr. Stone can be read in the Shonen Jump vault on Viz.com or streamed on Crunchyroll.