Bismuth ingestion

Bismuth ingested from therapeutic agents is mainly eliminated in the feces as bismuth sulfide. In general, 10-20% is excreted within 5 days, but elimination is still incomplete after 10 days (Iffland... 

Safety No industrial poisoning from bismuth has been reported (10). However, precautions should be taken against the careless handling of bismuth and its compounds ingestion and inhalation of dusts and fumes should be avoided. 

Bismuth is flammable as a powder. The halogen compounds of bismuth are toxic when inhaled or ingested. Some of the salts of bismuth can cause metallic poisoning in a manner similar to mercury and lead. 

Pharmacokinetics BSS undergoes chemical dissociation in the Gl tract. Two BSS tablets yield 204 mg salicylate. Following ingestion, salicylate is absorbed, with greater than 90% recovered in the urine plasma levels are similar to levels achieved after a comparable dose of aspirin. Absorption of bismuth is negligible. 

Bismuth is the least toxic of the As, Sb, Bi triad, which is unusual, since toxicity normally increases down a group, as shown by elements to the left of bismuth, i.e. Pb, Tl, Hg. However, it must be emphasized that this is not to say that bismuth is not toxic and experimentalists should avoid contact and ingestion of its compounds. 

There are many examples of relatively straightforward use of ICP-MS for the analysis of biological fluids. Antimony has been measured in blood after a 14 1 dilution [236]. Cesium serum levels were found to be elevated in patients with alcohol dementia but not in Alzheimer s disease patients [237]. Cobalt levels in rat serum depended on the form of cobalt [238] ingested. Bismuth levels were measured in human blood and urine by using a direct injection nebulizer [239]. Lead was measured in the blood and blood plasma of smelter workers and the general population [240]. The measurement of trace elements in serum by ICP-MS has been compared to results from neutron activation analysis and proton-induced x-ray emission [241]. Semiquantitative analysis can also be used to obtain a rapid screening of samples [242]. 

SAFETY PROFILE Poison by intraperitoneal route. Human systemic effects by ingestion fever, osteomalacia, and gastrointestinal effects. When coprecipitated with bismuth hydroxide and reduced by Ha, it is violendy flammable in air. Incompatible with chlorinated rubber. 

SAFETY PROFILE Low toxicity by ingestion. Questionable carcinogen with experimental tumorigenic data. See also BISMUTH COMPOUNDS and CARBAMATES. When heated to decomposition it emits very toxic fumes of SOx and NOx. 

Ruiz-Maldonado R, Contreras-Ruiz J, Sierra-Santoyo A, Lopez-Corella E, Guevara-Flores A. Black granules on the skin after bismuth subsahcylate ingestion. J Am Acad Dermatol 1997 37(3 Pt l) 489-90. 

Oral human LDlq is equal to 221 mgkg Adverse acute reactions to bismuth include acute renal failure following ingestion of excessive concentrations. Bismuth can cause nausea, vomiting, and abdominal pain within hours of exposure. Muscle cramps and weakness, blurred vision, and hyperreflexia may be exhibited. Liver transaminase activities may be elevated. 

Internally deposited naturally occurring radionuclides also contribute to the natural radiation dose from inhalation and ingestion of these materials when contained in air, food, and water. Included are radionuclides of lead, polonium, bismuth, radium, potassium, carbon, hydrogen, uranium, and thorium. Potassium-40 is the most prominent radionuclide in normal foods and human tissues. The dose to the total body from these internally deposited radionuclides has been estimated to be 39mremyear. ... 

Urea breath test HP urease breaks down ingested labeled C-urea, patient exhales labeled CO2 Tests for active HP infection 95% sensitive and specific results take about 2 days antibiotics, bismuth, PPIs, and H2RAS may cause false-negative results withhold PPIs or H2RAS (1 to 2 weeks) and bismuth or antibiotics (2 to 4 weeks) before testing may be used posttreatment to confirm eradication... 

Overall, 99% of ingested bismuth may be eliminated in this way (Fowler and Vouk 1986, Mueller 1989). In cases of encephalopathy, with remarkably high urine and blood levels (2000 and 1500 igL respectively), the half-lives of bismuth were calculated for urine (4.5 days) and blood (5.2 days) (Iffland 1993). Cerebrospinalis... 

Tab. 5.3 Blood concentrations, urinary excretion and renal clearance of bismuth in asymptomatic patients and in those with neurotoxicity after ingestion of bismuth salts...

The form in which Bi is ingested is important, and indicates the tenuous nature of proposed safe and toxic values for concentrations of bismuth in blood. For pharmaceutical use of Bi-containing compounds, the lower limit of Bi toxicity in blood has been proposed at 0.48pgL h Patients who had been ingesting bismuth subgallate but not showing any toxic symptoms, had a mean blood bismuth concentration of 0.18 xmolL with an overall range of 0.10 to 0.48 jmolL (Thomas et al. 1977). Except for one patient, all values were < 0.24 jmol L h Leonhardt and Klotz... 

Burns R, Thomas DW and Baron VJ (1974) Reversible encephalopathy possible associate with bismuth subgallate ingestion. Br Med J 1 220—223. Chaleil D and Aliain P (1980) Effect of oral administration of bismuth subnitrate on distribution and excretion of intrapcritoneally given radiobismuth in rats. Ann Pharm Fr 37 285-290. Chattopadhyay A and Jervis RE (1974) Multielement determination in market-garden soils by instrumental photon activation analysis. Anal Chem 46(12) 1630-1639. 

The mechanisms of bismuth toxicity have not been identified. Symptoms of bismuth poisoning include fever, weakness and rheumatism-like pain. Acute toxic effects, including renal failure, can develop following the ingestion of large concentrations of bismuth. Chronic exposure may cause gingivitis and black spots on the gums. 

The daily elimination in untreated people is estimated at 12 ixg [12] including 2.9 xg excreted with the urine [27]. Ingested bismuth from therapeutics is mainly eliminated with feces as sulfide. Within 5 days 10-20% is excreted. But elimination is not finished after 10 days. Overall 99% may be eliminated in this way [3,12,17,29]. Absorbed bismuth is mainly excreted by urine the biliary/fecal elimination route is only about half of the urinary one [3,6,62-64]. Half-lives in blood after a single dose or during a treatment depend on the kind of the Bi compound, the amounts ingested, and the blood levels. Elimination from blood of bismuth subcitrate is biphasic [17,28,65]. In cases of encephalopathy with remarkably high urine and blood levels (2000 and 1500 p-g/liter, respectively), half-lives were calculated for urine (4.5 days) and blood (5.2 days). Liquor levels decreased more slowly with a half-life of 15.9 days [53]. Elimination kinetics is also described as a three-compartment model with half-lives of 3.5 min, 0.25 hr, and 3.2 hr [6]. Biological half-times in humans are reported for the whole body 5 days, the kidney 6 days, and the liver 15 days (cited in [3]). 

Incidents with bismuth compounds and reports about bismuth encephalopathy were the reason to define concentrations in blood up to 50 (tg/liter as safety and above 100 p,g/liter as alarm levels [70]. Bismuth subcitrate in different forms is the most examined compound. Alarm levels can be exceeded for a short time after ingestion without toxic consequences [30,31,71]. Individual differences of blood or plasma levels and urine elimination can be large after single doses and also after several weeks of treatment [28]. Two hours after a single dose of 108 mg Bi as colloidal subcitrate plasma levels in two volunteers were measured as 1.62 and 24.7 p.g/liter [43]. Steady-state plasma levels after a treatment of 4-8 weeks ranged between 3 and 58 p.g/liter [19,28,43,64-66,68]. Urine levels were significantly increased at the end of the treatment from 100-130 xg/liter [68] to 530 p.g/liter [27]. 

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