The Haber Rule: The Effect of Poisonous Gas Concentration
Author: 'Woodnyet"
"In his studies of the effects of poison gas, Haber noted that exposure to a low concentration of a poisonous gas for a long time often had the same effect (death) as exposure to a high concentration for a short time. He formulated a simple mathematical relationship between the gas concentration and the necessary exposure time. This relationship became known as Haber's rule."
Fritz Haber was a German scientist during the time of the First World War. He was in charge of the notorious German chemical weapons program during the war. He invented many of the poison gases which were used, and was later criticized for his work. For all of the bad he had attained, he actually out did himself by his good discoveries, such as a commercially-feasible method of manufacturing ammonia, for fertilizers (thus saving the world from famine.) His motivation, however, may have been for the production of cheap ammonia, in order to manufacture explosives for wartime use.
He is credited with many other discoveries, one of which came to be known as 'Haber's Rule' (explained below.) I have done some research on the application of this principle to airborne particulate matter. See the links below to various studies which have suggested, or established, links to this well-known scientific principle.
Any airborne chemical compound which is non-polar (that is, non-water soluble; water is, by contrast, highly polar) can tend to collect in the lungs, or be absorbed into the bloodstream, where it ultimately ends up in a fat cell (fats are also non-polar, thus tend to attract the non-polar chemical to itself.) This is how airborne dioxins and polycyclic aromatic hydrocarbons terminally reach the body's fat cells, where they tend to continue to accumulate over time.
Haber's Rule may especially apply to wood smoke particles, since they tend to accumulate in the lungs, and are principally non-polar. The smallest of these particles, the less-than-2.5 micron particle size, may be the most destructive of all, since such small particles can traverse into the deepest recesses of the lungs.
Quote: "In his studies of the effects of poison gas, Haber noted that exposure to a low concentration of a poisonous gas for a long time often had the same effect (death) as exposure to a high concentration for a short time. He formulated a simple mathematical relationship between the gas concentration and the necessary exposure time. This relationship became known as Haber's rule."
Quote: "Haber's rule is a mathematical statement of the relationship between the concentration of a poisonous gas and how long the gas must be breathed to produce death, or other toxic effect. The rule was formulated by German chemist Fritz Haber in the early 1900s.
Haber's rule states that, for a given poisonous gas, , where C is the concentration of the gas (mass per unit volume), t is the amount of time necessary to breathe the gas, in order to produce a given toxic effect, and k is a constant, depending on both the gas and the effect. Thus, the rule states that doubling the concentration will halve the time, for example.
Haber's rule is an approximation, useful with certain inhaled poisons under certain conditions, and Haber himself acknowledged that it was not always applicable. It is very convenient, however, because its relationship between C and t appears as a straight line in a log-log plot. In 1940, statistician C. I. Bliss published a study (Bliss, 1940) of toxicity in insecticides in which he proposed more complex models, for example, expressing the relationship between C and t as two straight line segments in a log-log plot. However, because of its simplicity, Haber's rule continued to be widely used. Recently, some researchers have argued (Miller et al., 2000) that it is time to move beyond the simple relationship expressed by Haber's rule and to make regular use of more sophisticated models."
Haber's Rule Wikipedia Entry
Haber's Rule is cited in these articles:
Habers rule... cumulative ... together with ozone, especially PM10 particulates ... http://ec.europa.eu/health/ph_risk/committees/sct/docshtml/sct_out38_en.htm
On the Importance of Exposure Variability to the Doses of Volatile Organic Compounds S. M. Rappaport*,1, L. L. Kupper and Y. S. Lin* http://toxsci.oxfordjournals.org/cgi/content/full/83/2/224
Toxicity of Military Smokes and Obscurants/Committee on Toxicology, Commission on Life Sciences, National Research Council http://books.nap.edu/catalog.php?record_id=5582
PDF files
Characteristics of atmospheric particulate matter http://nepap.ivl.se/Reports/NEPAP_MLA_WP5.pdf
Research Priorities for Airborne Particulate Matter http://www.epa.gov/oppt/aegl/pubs/tsd65.pdf
Other Publications: American Chemistry Council Long-range Research (PDF file) http://www.americanchemistry.com/s_acc/bin.asp?CID=1401&DID=5114
PayPerView: Prediction of the Toxic Effects of Fire Effluents/Gordon E. Hartzell http://jfs.sagepub.com/cgi/content/abstract/7/3/179?ck=nck
About Haber's Rule:
Toxicology (next 4 articles:) http://www.sciencedirect.com/science/journal/0300483X
The use of Haber’s Law in standard setting and risk assessment David W. Gaylor/Toxicology/Vol149/no1
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/Toxicology/Vol149/no1 Frederick J. Miller, , Paul M. Schlosser and Derek B. Janszen
The role of time in toxicology or Haber’s c×t product Karl K. Rozman/Toxicology/Vol149/no1
The Haber-Weiss reaction and mechanisms of toxicity*1 James P. Kehrer/Toxicology/Vol149/no1