Haber's rule
The Haber's rule is in the toxicology used mathematical relationship between the concentration of a toxic substance and the duration of administration, or exposure , this poison. Haber's rule is named after the German chemist Fritz Haber , who first established this dose-duration relationship when exposed to poisonous gases , including phosgene .
Concentration × duration = constant
Haber’s rule states that a constant product of concentration (c) and duration (t) corresponds to a constant biological effect (k):
The biological effect can be a disease (e.g. cancer ) or the death of the exposed living being.
In other words, Haber's rule states that identical products in terms of concentration and duration of administration lead to the same effect. This means that if a subliminally toxic dose is constantly added, the toxicity increases over time.
The hyperbolic curve shape results in the diagram (see Figure 1) with linearly scaled axes . In a double logarithmic representation, however, a straight line.
In the Anglo-Saxon literature, the terms Haber's Law and Haber's Rule are used for Haber's rule .
Examples
Examples of the validity and applicability of Haber's rule are tobacco smoking with the effect of lung cancer and the effect of ionizing radiation on body tissue ( ultraviolet radiation → skin cancer ).
restrictions
Haber's rule is only applicable in the case of irreversible effects of summation poisons (also called accumulation poisons or c · t poisons) such as lead , mercury and all carcinogenic substances . In the case of vital trace elements such as selenium or zinc , the rule fails completely at low concentrations. In the case of concentration poisons such as carbon dioxide , Haber's rule is also not applicable.
See also
Individual evidence
- ↑ F. Haber: On the history of the gas war. In: Five lectures from the years 1920-1923 Julius Springer, 1924.
- ↑ H. Druckrey and K. Küpfmüller: Quantitative analysis of cancer development. In: Journal of Nature Research B . 3, 1948, pp. 254–266 ( PDF , free full text).
literature
- J. Doull and KK Rozman: Using Haber's Law to define the margin of exposure. In: Toxicology 149, 2000, pp. 1-2. PMID 10963856
- DW Gaylor: The use of Haber's Law in standard setting and risk assessment. In: Toxicology 149, 2000, pp. 17-19. PMID 10963857
- KK Rozman: The role of time in toxicology or Haber's c × t product. In: Toxicology 149, 2000, pp. 35-42. PMID 10963859
- KK Rozman and JJ Doull: The role of time as a quantifiable variable of toxicity and the experimental conditions when Haber's c × t product can be observed: implications for therapeutics. In: J Pharmacol Exp Ther 296, 2001, pp. 663-668. PMID 11181890
- KK Rozman: Delayed acute toxicity of 1,2,3,4,6,7,8-tetracholordibenzo-p-dioxin (HpCDD) after oral administration obeys Haber's rule of inhalation toxicology. In: Toxicol Sci 49, 1999, pp. 102-109. PMID 10367347
- SA Saghir et al .: Validation of Haber's Rule (dose × time = constant) in rats and mice for monochloroacetic acid and 2,3,7,8-tetrachlorodibenzo-p-dioxin under conditions of kinetic steady state. In: Toxicology 215, 2005, pp. 48-56. PMID 16076519
- MV Evans et al .: A comparison of Haber's rule at different ages using a physiologically based pharmacokinetic (PBPK) model for chloroform in rats. In: Toxicology 176, 2002, pp. 11-23. PMID 12062926
- CI Bliss: The relationship between exposure, time, concentration and toxicity in experiments on insecticides. In: Annals of the Entomological Society of America 33, 1940, pp. 721-766.
- FJ Miller et al .: Haber's rule: a special case in a family of curves relating concentration and duration of exposure to a fixed level of response for a given endpoint. In: Toxicology 149, 2000, pp. 22-34. PMID 10963858
- H. Witschi: Some Notes on the History of Haber's Law. (PDF; 90 kB) In: Toxicological Sciences 50, 1999, pp. 164-168. PMID 10478852
- H. Witschi: Fritz Haber: December 9, 1868-January 29, 1934. In: Toxicology 149, 2000, pp. 3-15. PMID 11023428
Web links
- Heberer, Introduction to Toxicology (PDF; 493 kB), MLU Halle-Wittenberg