Epigraphs Note on Terminology Acknowledgments Introduction

48. See 2001 ACGIH TLV, data summary for HF, “based on results of controlled
inhalation studies in human volunteers” (Largent cited). ACGIH also cite E.
Ronzani, “Influence of the Inhalation of Irritant Industrial Gases on the Resistance
of the Organism to Infectious Disease. Experimental Investigations. II.
Hydrofluoric Acid Gas, Ammonia, Hydrochloric Acid Gas,” Arch. Hyg., vol.
70 (1909), pp. 217–269. Ronzani was prompted to his studies because “disputes
about the duties of factory and workshop owners towards their neighbors are
brought to the court in rising frequency.” He therefore sought a “no effect”
level to help resolution of such disputes. He studied animals at various concentrations
of HF, including 7.5 ppm and 5.0 ppm, but was forced to go to 3
ppm to find a no-effect level over 31 days—little comfort surely almost a century
later for workers breathing HF today at 3 ppm for all of a working life.
In the NIOSH “Criteria Document for a Recommended Standard: Occupational
Exposure to Hydrogen Fluoride,” Publication 76-143, it is noted that
Elkins had found “workers in the etching process had nosebleeds as did welders
exposed to 0.4–0.7 mg F/cu m who were excreting 2–6 mg F/liter of urine .
. . other workers exposed to 0.1–0.35 mg F/cu m and excreting, on the average,
4.5 mg F/liter reportedly experienced sinus trouble. The ACGIH suggested
that the urinary excretion values reported by Elkins seemed ‘inconsistently
high’ relative to airborne HF levels, and that dietary F was suggested as a
possible factor.” Citation, H. B. Elkins, The Chemistry of Industrial Toxicology,
2nd ed. (New York: John Wiley and Sons, Inc., 1959), pp. 71–73.
The ramifications of the ACGIH reliance on Largent and Ronzani can
perhaps be seen in the U.S. standard for HF occupational exposure of 2.5 mg
HF/cu m, compared to other countries (cited in NIOSH, above document,
1976): The (former) Soviet Union, 0.5 mg HF/cu m, Hungary and Poland 0.5
mg HF/cu m, (the former) East Germany and Czechoslovakia, 1 mg HF/ cu
m, and Bulgaria 1 mg HF/cu m.
49. In that second interview, Largent became aware that the interviewer Joel
Griffiths might not view his experimental work favorably. The verbatim
exchange continued as follows:
EL: I never did develop osteofluorosis.
JG: Excuse me?
EL: I never developed personally any aspect of osteofluorosis—you just got
through saying I developed osteofluorosis.
JG: Because I think that is what you told me the last time we talked.
EL: No—I would have talked about skeletal deposition, and that is not osteofluorosis.
JG: Well, skeletal deposition, right—that led to some difficulties with your
knees.
EL: Not in the slightest.
JG: Well, this doesn’t seem to jibe with what you told me the first time.
EL: That’s not true—I was developing more like osteoporosis—I have arthritic
difficulties in my extremities serious enough that the right knee was