© 2003 Robert A. Freitas Jr. All Rights Reserved.

Robert A. Freitas Jr., Nanomedicine, Volume IIA: Biocompatibility, Landes Bioscience, Georgetown, TX, 2003

15.1.1 Mechanical Damage from Ingested Diamond

One informal anecdotal modern source [100] has described diamond dust as “perhaps the most terrible poison in existence. Every other poison has a principle behind its action – cyanides attack, alkaloids destroy, barbiturates deaden, glycosides deteriorate, ricin and abrin phytotoxins agglutinate. Diamond dust abrades.”

Hutchkinson* [100] continues: “If one ingests diamond dust, the natural peristaltic motion of the digestive tract causes these tiny splinters of the world’s hardest substance to imbed themselves along the alimentary canal, the natural motions of the inner body causing them to work deeper and deeper until your internal organs are perforated and ripped apart. This goes on from anywhere between 2-6 months, until the victim is dead. The pain accompanying this can only be imagined by the few. A large amount of diamond dust would probably feel similar to having a Portuguese Man-O-War living inside of you. Even in its earliest stages, the difficulties behind diagnosis can well be imagined. The only way to extricate the tiny diamond splinters is surgery, wherein each particle would have to be located and removed individually, an impossible feat.”

* It is important to note that Hutchkinson is writing informally and in a historical context. He is neither a surgeon nor a pathologist and evidently has no experience in the diagnosis or characterization of the pathophysiology of diamond dust ingestion. M. Sprintz notes that diamond would be visible radiographically, and a modern pathologist would definitely identify the particles after exploratory surgery was performed in a modern case of diamond poisoning. Death might also be caused by a peritoneal infection with subsequent sepsis secondary to the bowel perforation.

In ancient times, diamonds were regarded as having magical curative powers. According to Pliny the Elder (23-79 AD) in his Natural History, diamond “prevails over all poisons and renders them powerless, dispels attacks of wild distraction and drives groundless fears from the mind.” It was once thought that diamond powder, taken orally, possessed curative abilities [101]. Physicians in the Middle Ages debated this subject at great length and were of divided opinion, though the proponents of such treatment met with many notable failures. Apparently, wealthy people were still being dosed with ground diamonds to cure them of stomach disorders well into the 16th century [102]. For example, Pope Clement VII (Giulio de’ Medici) died on 25 September 1534 when his doctors failed to cure his ailments – the bill for the fourteen spoonfuls of precious stones he had been administered is said to have been 40,000 ducats [103]. As late as the 19th century, some of the wealthy citizens of India had diamond powder applied to their teeth in an attempt to repair decay [104]. (The powder supposedly also provided protection from lightning.) Even today, diamonds are found in the “precious pills” of traditional Tibetan medicine [99].

More commonly, though, diamond was regarded as a potential poison. Up until the 18th century, rumor had it that even uncrushed diamonds were poisonous, a fantasy that those who owned or mined the stones no doubt wished to promote [104]. This is because a favorite and effective means of stealing a diamond was to swallow it whole and wait a few days for it to pass through the digestive system. The myth that stones were poisonous presumably deterred many would-be gem thieves from the attempt [102, 104]. We now know that uncrushed diamond is a neutral contributor to the human diet, doing neither good nor harm – a swallowed diamond gemstone “re-emerges in due course” [102].

Other stories suggested that fragmented diamonds were even more hazardous. The splinters produced by shattering a diamond, which Pliny knew could “make hollows in the hardest materials,” are easily capable of cutting the stomach and intestines of anyone who swallows them [102]. One writer [96] reports that Paracelsus was poisoned by diamonds. Sultan Bejazet II, leader of the Ottoman Empire (Turkey), was reportedly assassinated in 1512 by his son Selim, who fed the Sultan a fatal dose of pulverized diamond mixed in with his food [97, 98]. Some claim that Frederick II, emperor of the Holy Roman Empire, also died after imbibing a fatal dose of diamond powder [98], and that the Countess of Essex poisoned Sir Thomas Overbury with mercury and diamond dust in 1613 while he was imprisoned in the Tower of London [97]. Diamond splinters have been used as a murder weapon through the ages and in different societies [102]. For example, a member of the Bengal Civil Service, William Crooke [105], writing at the beginning of the 20th century, tells us that in India “as an irritant poison, pounded glass has been often used. But diamond dust enjoyed a still higher reputation...it is believed in South India to be at once the least painful, the most active and infallible of all poisons. It was kept as a last resort in times of danger.”

During the Renaissance, it was widely believed that diamond powder had pernicious properties, for by then it was realized that the powder rarely cured and apparently often killed [101]. The poisoner became an integral part of the political scene [106]. Catherine de Medici (1519-1589) reportedly used diamond powder to eliminate certain people who were acting against her. Her enemies called the mixture she prepared “the powder of succession,” though one observer averred that the principal toxic component of the powder might have been added arsenic [104]. According to another account, the methods of Catherine de Medici depended on developing direct evidence to arrive at the most effective compounds for her purposes. Under guise of delivering provender to the sick and the poor, Catherine reportedly tested toxic concoctions, carefully noting the rapidity of the toxic response (onset of action), the effectiveness of the compound (potency), the degree of response of the parts of the body (specificity, site of action), and the complaints of the victim (clinical signs and symptoms) [106].

Diamond dust became a rather popular means of assassination during the Renaissance. One classical discussion of this technique may be found in the autobiography of Benvenuto Cellini [107], the famous Italian goldsmith and sculptor, who described a botched attempt on his life by his enemy, the powerful Pierluigi Farnese, son of Pope Paul III, which took place in 1539 while Cellini was imprisoned in Rome by the Pope. Cellini writes:

“Messer Durante of Brescia engaged the soldier (formerly druggist of Prato) to administer some deadly liquor in my food. The poison was to work slowly, producing its effect at the end of four or five months. They resolved on mixing pounded diamond with my victuals.”

“Now, the diamond is not a poison in any true sense of the word, but its incomparable hardness enables it, unlike ordinary stones, to retain very acute angles. When every other stone is pounded, that extreme sharpness of edge is lost; their fragments become blunt and rounded. The diamond alone preserves its trenchant qualities. Wherefore, if it chances to enter the stomach together with food, the peristaltic motion needful to digestion brings it into contact with the coats of the stomach and the bowels, where it sticks, and by the action of fresh food forcing it farther inwards, after some time perforates the organs. This eventually causes death. Any other sort of stone or glass mingled with the food has not the power to attach itself, but passes onward with the victuals.”

“Now Messer Durante entrusted a diamond to one of the guards, and it is said that a certain Lione, a goldsmith of Arezzo, my great enemy, was commissioned to pound it. The man happened to be very poor, and the diamond was worth some scores of crowns. He told the guard that the dust he gave him back was the diamond in question, properly ground down. The morning when I took it, they mixed it with all I had to eat. It was a Friday, and I had it in salad, sauce, and pottage. That morning I ate heartily. It is true that I felt the victuals scrunch beneath my teeth, but I was not thinking about knaveries of this sort. When I had finished, some scraps of salad remained upon my plate, and certain very fine and glittering splinters caught my eye among those remnants. I collected them, and took them to the window, which let a flood of light into the room, and while I was examining them, I remembered that the food I ate that morning had scrunched more than usual. On applying my senses strictly to the matter, the verdict of my eyesight was that they were certainly fragments of pounded diamond. Upon this I gave myself up without doubt as dead....”

“Now, hope is immortal in the human breast. Lured onward by a gleam of idle expectation, I took up a little knife and a few of these particles, and placed them on an iron bar of my prison. Then I brought the knife’s point with a slow strong grinding pressure to bear upon the stone, and felt it crumble. Examining the substance with my eyes, I saw that it was so. In a moment new hope took possession of my soul. Messer Durante, my enemy, or whoever it was, gave a diamond to Lione to pound for me of the worth of more than a hundred crowns. Poverty induced him to keep this for himself, and to pound for me a greenish beryl of the value of two carlins, thinking perhaps, because it also a stone, that it would work the same effect as the diamond....”

In 1995, the author undertook a modest informal experiment to confirm the potentially dangerous shardlike quality of pounded diamonds, as claimed by Cellini. Diamond grit was acquired and pounded using a simple apparatus, then carefully cleaned and visually examined using a scanning electron microscope (SEM).* Even a single hammer blow produced numerous particles of a wide variety of sizes (0.1-100 micron), many possessing sharp ragged “fishhook” edges, deep angular concavities, serrations, irregular holes, and other interesting features on the order of a few microns in size (Figures 15.1 and 15.2), which is in stark contrast with the relatively smooth-looking (unpounded) diamond particle microphotographs reproduced in McCrone’s Particle Atlas [109]. Figure 15.3 shows a pound-particle that is star-shaped with several jagged edges at a magnification of 300X. At 8000X, the uppermost tip of the star (Figure 15.4) reveals even smaller-scale serrations with several concave “fishhook” features measuring ~250 nanometers in diameter (a plausible size for a detached nanorobot manipulator arm). Some grit particles appear to be aggregates of much smaller particles, so it is possible that the pounding allows crystal fragments to dislodge irregularly, leaving behind concave holes. However, there also appear to be many concave fracture features present in each of the samples. Under the microscope, unpounded grit particles generally appear smoother and more rounded. The author also observed that the pounded grit tended to cling to human skin, especially in the narrowest creases of the fingers, producing a slight itching sensation, whereas unpounded grit generally does not.

* Diamond grit of 250-micron mesh size was obtained from Crystalite Corp. [108]; the cost was $3-$4/carat, depending on mesh size which can range from 100 mesh (~250-micron particles) down to 100,000 mesh (~250 nanometer particles). The grit was pounded between a steel anvil and a steel rod using a single blow from a 600-gm hammer dropped through a ~3-inch vertical fall. The crush was washed with 31% HCl to dissolve any metal fragments, then rinsed in distilled water several times and finished with an acetone drying rinse. Crushed samples were examined using a Zeiss Ultraphot II optical microscope at 125X and a JEOL JSM-35C SEM (kindly made available to the author by Dr. Elizabeth Mathews at San Joaquin Delta College, California) at various magnifications from 180X up to 12,000X, and were subjectively compared to uncrushed powder.

The author is unaware of any direct study of the mobility of fractured diamond shard in human tissues, that might confirm or disprove the historical and anecdotal evidence reported above. Crystalite Corp. [108] confirms that there are no major health warnings associated with the normal use of commercial diamond grit in jewelry-related grinding operations.* Classic toxicology textbooks make no mention of diamond as a poison [174], and this author could find no mention of powdered or pounded diamond in any of dozens of well-known standard modern reference works on medical toxicology, poisons, or forensic toxicology, or in the journal literature, although this would not be entirely unexpected given the likely rare incidence of accidental diamond shard ingestion or attempted homicide by diamond, especially in the 20th century. The diamond content of waste particles abraded into the mouth from diamond burs [111-114] on dental drills during clinical use is apparently considered relatively nonhazardous in comparison with the accompanying release of metallic ions such as Ni⁺⁺ into the body fluids during these procedures [115].

* One Material Safety Data Sheet (MSDS) for diamond grit [2392] describes the primary acute and chronic health hazard as “inhalation: pneumoconiosis and mucous membrane irritation,” recommends that spills may be cleaned up the same way as “for handling unregulated dust and sand,” notes that there is no known carcinogenicity, but warns that workers should “minimize inhalation and direct skin contact.” Another MSDS for pure diamond powder [2393] warns that grinding may produce dust that is “potentially hazardous when inhaled, swallowed, or comes into contact with eyes – may irritate eyes.” Yet another diamond powder MSDS [2394] warns of acute/chronic tissue irritation if the material is inhaled or ingested, or if it comes into contact with skin or eyes.

Broadening the search only yields additional conflicting data. For example, it is well known in veterinary medicine that ingested string can loop around epithelial folds and cut through a dog’s digestive tract [116], and similar cases have been reported in humans [122]. On the other hand, a weighted gelatin capsule trailing a 140-cm length of absorbent nylon line that is swallowed by a human patient, then safely pulled back out through the mouth 3.5 hours later, is sometimes used to test bile composition and bacterial content of the gut, and is commonly known as the “string test” [117-119].

Similarly, gastric and colon perforation with peritonitis has been reported [120-124] in cases of pica [125-133], with mixed pica (especially involving ingested paper, plastic bags, cloth and string) more likely to require surgery and to cause perforation [122]. Abrasive household cleaners largely composed of pumice or silica can cause gastrointestinal irritation but have a low order of toxicity [174], as with lithophagy [126], although massive ingestion of sand can cause intestinal blockage [134], diarrhea [135], or tooth wear [136]. Cases of foreign body ingestion including broken glass [137, 138], glass splinters [139-141], bent hypodermic needles and pins [142-144], fishhooks [145], razor blades [146-149], wires [150], wire springs [147], coins [132, 144, 151-153], screwdrivers [154], dentures [153] or knocked-out teeth [155] have produced esophageal perforation but generally are not regarded as life-threatening except in cases of complete obstruction of the intestine or colon [148, 156] or concurrent metal poisoning [157, 158]. Most (80-90%) [159-162] ingested foreign bodies that reach the stomach can be eliminated uneventfully through the gastrointestinal tract [163], but perforation may occur with ingestion of long, sharp pointed objects [164] or animal bones [148, 153], and is more frequent among those who have had previous abdominal surgery or intestinal diseases [148]. In one unusual case [165], an ingested plastic bag clip was found by radiography to have clipped itself to the small bowel mucosa.

The author concludes that there is sufficient uncertainty and necessity to warrant a study to rigorously assess the mechanical toxicity in human tissues of diamond dust and fractured diamond particles, as crude proxies for medical nanorobotic diamondoid detritus. (See also Section 15.4.3.3.2.)

Post-publication note: Peder Schultz [personal communication, June 2005] reports feeding commercial-grade diamond powder to animals with no ill effects. “In the first tests, 5 carats of diamond powder (300-1600 mesh) were given to dogs, mixed into the food so that the powder would come into contact with tissue in the mouth, to test the effect on the entire digestive system. No toxic effect was observed. A cat was then fed with 2/3 meat and 1/3 diamond dust (5 carats of 300-1600 mesh) for a short period. A considerable part of its digestive system must have been filled with diamond powder for some time. No symptoms have been observed after a year – the cat is still well and shows no sign of any illness.”

Last updated on 19 September 2005