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American Journal of Industrial Medicine 26:133-143 (1994)
American Conference of Governmental Industrial Hygienists: Low Threshold of Credibility
Barry I. Castleman, scO, and Grace E. Ziem, mo, orPH
Key words: risk assessment, philosophic perspectives, occupational health, TLVs, conflict of in terest, corporate influence
"F.T. Bodurtha reviewed with subcommittee members the importance of re porting TLV data which can be used by ACGIH as a basis for establishing threshold limit values. This is particularly important in those cases where Du Pont feels that the TLV presently is too low."
Du Pont Memo, September 1, 1966
INTRODUCTION A recent article [Rappaport, 1993] on the threshold limit values (TLVs) credits
the American Conference of Governmental Industrial Hygienists with reforming its practices, saying: "ACGIH-has developed formal procedures to guard against con flicts of interest." Unfortunately, ACGIH has done practically nothing to assure that conflicts of interest will be avoided by members of the TLV committee.
The TLV committee has been criticized for having corporate employees, retir"ees, and consultants take the primary role of drafting the documentary bases of TLVs for chemicals made by their corporate employers and clients. Yet committee members are not required to disclose even to ACGIH the sources of income they receive from consulting; public disclosure of such income sources, which is a requirement for members of scientific advisory committees to U.S. government agencies, has been discussed within ACGIH and was bitterly resisted.
The conflict of'interest "policy" consists of a mere understanding that, if a member of the committee suspects that he or she may have a conflict of interest, that should be discussed with the TLV committee chair and resolved. This ensures that, to the extent that conflicts of interest are of concern on the committee, they will be handled in such a way that there is no public disclosure of the issues involved or the manner of their resolution. ACGIH declined to explicitly prohibit committee mem bers from being involved in developing TLVs for substances produced by firms with which they have financial relationships.
Address reprint requests to Dr. Castleman, 1722 Linden Avenue. Baltimore, MD 21217. Accepted for publication July 13, 1993.
J 1994 Wiley-Liss, Inc.
134 ACGIH: Low Threshold of Credibility
Why must so much reliance be placed on the judgment and consciences of TLV committee members who have opposed more substantial guarantees to safeguard against such conflicts of interest? If working on the TLV committee is an act of public service, and it clearly is for some committee members, why not demonstrate that by embracing modern practices of openness?
The newest edition of the Documentation ofTLVs and BEIs [ACGIH, 1991 1993] reflects the most obvious and disappointing response by ACGIH to charges of corporate influence on the TLVs over the past 5 years. Removed are citations to unpublished corporate communications that were critical in setting TLVs for over 100 substances [Castleman and Ziem, 1988]. The new documentations for individual substances are revised and reference only published literature. The problem is, the TLVs that were based on the old "references" were not subjected to review in the course of this process. The new Documentation plainly indicates that, for 85% of the substances whose documentations were revised in 1991, TLVs had not been scruti nized for the preceding 5 years. In a rare case in which a committee member rec ommended that a TLV be reviewed based on the data found in revising a documen tation, the recommendation was voted down (ethylene oxide). By revising the Documentation but not the TLVs, ACGIH concealed corporate influence instead of eliminating it.
TLV committee minutes and ACGIH Board of Directors minutes about TLVs are regarded as private records by ACGIH and will not be publicly disclosed by ACGIH. Minutes of the TLV committee and some subcommittee minutes have none theless been located, and offer an impressive record of corporate influence.
The minutes reveal that primary responsibility for drafting documentations to serve as the bases for new TLVs for specific substances was frequently assigned to corporate employees and consultants. Though this has been noted before [Castleman and Ziem, 1988; Ziem and Castleman, 1989], Table I is the most complete record of this kind to appear in print. Table I, which is in all likelihood a less-than-complete record of these assignments, shows that more than 40 products of Dow Chemical were assigned to Dow toxicologist Theodore Torkelson. Another 20 were DuPont products assigned to DuPont employees James Morgan and Gerald Kennedy. Similar contributions were made by representatives of Bayer and Exxon.
ACGIH claims that the full TLV committee approves of all TLVs and is col lectively responsible for the result. But in practice, the process depends very much on the thoroughness and impartiality of individuals preparing the documentations. A typical TLV committee meeting can cover 20-30 substances. Each member has documentations to prepare in addition to vetting those presented by the other mem bers. Even if all the documentations and all supporting references were made avail able to all committee members in advance of meetings, which has never been done, it would be an enormous job for a member to analyze everything and come prepared to critique it. How many people doing this work as unpaid volunteers can find the time and resources to locate important works omitted by others in their documenta tions?
The weakness of the process in depending so much on the work of individuals on the TLV committee is reflected in the inaccuracies in the 1986 Documentation catalogued by Roach and" Rappaport [1990]. There was no checking of the reference citations by the TLV committee chairmen, ACGIH staff, or anybody else. And it does not appear that the ACGIH Board got involved in developing specific TLVs until the
. 7"\
Approaches to Rlisk Assessement
135
TABLE I. TLV Chemical Assignments to Corporate Representatives*
Substance
Acrylamide
Acrylonitrile
Amitrole
Asbestos
Azodrin
Bis-chloroethyl ether
Bromacii ("Hyvar X")
Bromochloromethane
Bromodiphenyls .
Calcium hydroxide
Caprolactam Cartwn tetrabromide
Carbon tetrachloride Chlorine
-
Chloroacetic acid
Chloroacetone
Chloroacetyl chloride
Chlorodifluoromethane
Chloroform
Chloromethyl methyl ether
Chloropcntafluoroethane
Chloroprene
2-Chloropropionic acid
o-Chlorostyrene
2 Chloro-6-trimethyl pyridine ("N-Serve")
Chlorpyrifos ("Dursban")
Chromates
Clopidol ("Coyden")
Crufomate ("Ruelene")
Cyanamide
Cyciopentadiene
Cyclopentane
Dibromochloropropane
Dichloromonofluoromethane
1.2 Dichloropropane (propylene dichloride)
1.3 Dichloropropane
1,3 Dichloropropene ("Telone")
Dicrotophos ("Bidrin")
Dicyclopentadiene
Dimethylate
Dimethyl formamide
Dimethyl hydrazine
Dimethyl sulfate
Dimethyl sulfoxide
3,5 Dinitro-o-tolamide ("Zoalene")
Dioxane
Dioxin
Dipropylene glycol methyl ether ("Dowanol DPM")
Diuron ("Karmex")
Divinylbenzene
Epichlorohydrin
Ethanolamine
'
2-Ethoxyethanol
Person assigned (company)
T. Torkelson (Dow')
T.T. (Dow). J. Morgan (DuPont')
T.T. (Dow), G. Kimmerle (Bayer1)
P. Gross (asbestos companies')
M. Zavon (Ethyl)
T.T. (Dow)
J.M. (DuPont')
T.T. (Dow')
T.T. (Dow)
T.T. (Dow)
T.T. (Dow')
T.T. (Dow)
T.T. (Dow') subcommittee
T.T. (Dow')
T.T. (Dow')
T.T. (Dow)
T.T. (Dow')
J.M. (DuPont')
T.T. (Dow')
T.T. (Dow)
J.M. (DuPont')
-
J.M. (DuPont')
T.T. (Dow') subcommittee
T.T. (Dow)
T.T. (Dow')
T.T. (Dow')
J.M. (DuPont')
T.T. (Dow')
T.T. (Dow')
J.M. (DuPont)
T.T. (Dow)
J.M. (DuPont), J. Hammond (Exxon)
T.T. (Dow')
J.M. (DuPont')
T.T. (Dow')
T.T. (Dow)
T.T. (Dow')
M.Z. (Ethyl)
T.T. (Dowb)
T.T. (Dow)
J.M. (DuPont')
J.M. (DuPont)
J.M. (DuPont')
J.M. (DuPont)
T.T. (Dow')
T.T. (Dow')
T.T. (Dow')
T.T. (Dow')
J.M. (DuPont')
T.T. (Dow')
T.T. (Dow') subcommittee
T.T. (Dow')
T.T. (Dow)
(continued)
`^
\
/
136 ACGIH: Low Threshold of Credibility
r
TABLE I. TLV Chemical Assignments to Corporate Representatives* (Continued)
Substance
Person assigned (company)
2-Ethoxyethyl acetate
Ethyl chloride
Ethylene chlorohydrin
Ethylene diamine
Ethylene dibromide (1,2 dibromoethane)
Ethylene dichloride (1,2 dichloroethane)
Ethylene glycol
Fenamiphos ("Nemacur")
Fenthion ("Baytex")
Fibrous glass
Formamide
Gasoline Hexabromodiphenyl
Hexachlorobutadiene Hexachlorocyclopentadiene
Hexachloroethane
Hexafluotoacetone
Hexamethyl phosphoramide
itHexane
Hydrazine
Hydrogen cyanide
2-Hydroxypropyl acrylate
Iodoform
Isohexane
Isoparaffin
Isophthalonitrile
Kerosene, deodorized
Ketene
Liquefied petroleum gas (LPG)
Malathion
Methomyl ("Lannate")
2-Methoxymethanol
2-Methoxyethylacetate
Methyl bromide
Methyl chloride
4,4'-Methylene bis (2-chIoroaniline) ("MOCA")
Methylene bis(4-cyclohexyl isocyanate)
Methylene chloride
4,4' Methylene dianiline
Methyl hydrazine
N-methyl pyrrolidone
.
Metribuzin ("Sencor")
Morpholine
Naphtha, VM & P
p-Nitrochlorobenzene
Octabromodiphenyl
Perchloroethylene
Perchloromethyl mercaptan
Perfluoroalkanes
Perfluorooctanoic acid
Phenyl betanaphthylamine
Phenylene diamine
'
Phenyl hydrazine
T.T. (Dow) T.T. (Dow) T.T. (Dow) T.T. (Dow1) T.T. (Dow1) T.T. (Dow1) T.T. (Dow1) G. Kimmerle (Bayer/Mobay1) G.K. (Bayer/Mobay1) P.G. (insulation manufacturing association1) J.M., G.L. Kennedy (DuPont1) J. Hammond (Exxon1) T.T. (Dow) T.T. (Dow) T.T. (Dow) T.T. (Dow) J.M. (DuPont1) J.M. (DuPont1) J.H. (Exxon1) G.L.K. (DuPont) J.M. (DuPont1) J.M. (DuPont) T.T. (Dow) J.H. (Exxon) J.H. (Exxon) M.Z. (Ethyl) T.T. (Dow) M. Zavon (Hooker Chemical) J.H. (Exxon1) M.Z. (Hooker) J.M. (DuPont1) M.Z. (Hooker), T.T. (Dow) M.Z. (Hooker). T.T. (Dow) T.T. (Dow1) T.T. (Dow1) J.M. (DuPont1) G.L.K. (DuPont) T.T. (Dow1) T.T. (Dow1) subcommittee G.L.K. (DuPont) J.M. (DuPont) G.K. (Bayer/Mobay1) G.L.K. (DuPont) J.H. (Exxon1) G.L.K. (DuPont1) T.T. (Dow) T.T. (Dow1) G.K. (Bayer/Mobay1) J.M. (DuPont) G.L.K. (DuPont) J.M. (DuPont) G.K. (Bayer/Mobay1) G.L.K. (DuPont)
(continued)
Approaches to Risk Assessement
137
TABLE I. TLV Chemical Assignments to Corporate Representatives* (Continued)
Substance
Phosgene
m-Phthalodinitrile
Picloram ("Tordon")
Propylene glycol methyl ether ("Dowanol PM")
Stoddard solvent
Styrene
Sulprofos ("Bolstar")
2,4,5-T Tetrachloronaphthalene
Tetramethyl thiourea
Thiram
Tin, organo m-Toluene diamine o-Toluidine 1,2,3 Trichlorobenzene
.
1,2,4 Trichlorobenzene
.
1,1,1 Trichloroethane
1,1,2 Trichloroethane
Trichloroethylene
1,2,3, Trichloropropane
Trichlorotrifluoroethane
Tricyclohexyltin hydroxide ("Plictran," cyhexatin)
Trifluorobromomethane
Tris(2,3 dibromopropyl phosphate)
Vinyl bromide
Vinyl chloride
Vinyl fluoride
Vinylidene chloride
Vinylidene fluoride
m-Xyiene, a,a'-diamine
Xylidine
Person assigned (company)
J.M. (DuPont*) M.Z. (Ethyl) T.T. (Dow*) T.T. (Dow*) J.H. (Exxon*) T.T. (Dow*) G.K. (Bayer/Mobay*) V.K. Rowe (Dow*) T.T. (Dow) M.Z. (Occidental Chemical) G.K. (Bayer/Mobay*) T.T. (Dow) J.M. (DuPont*) G.K. (Bayer/Mobay*) T.T. (Dow) T.T. (Dow*) T.T. (Dow*) T.T. (Dow*) T.T. (Dow*) T.T. (Dow*) J.M. (DuPont*) T.T. (Dow*) J.M. (DuPont*) T.T. (Dow) and J.M. (DuPont) T.T. (Dow) T.T. (Dow*) T.T. (Dow) T.T. (Dow*) T.T. (Dow) J.M. (DuPont) G.K. (Bayer/Mobay*)
Sources: TLV committee minutes, fragmentary TLV subcommittee minutes, and TLV Committee spreadsheets, 1970-1988; Directory of Chemical Producers. 1986; Chemical Week Buyers' Guide, 1976 and other years; Synthetic Organic Chemicals, U.S. International Trade Commission, 1972-1986: and personal communications with present and former TLV committee members. "Product of the company at or before time that the TLV documentation was assigned. bProduct of the company after the time that TLV documentation was assigned.
Formaldehyde Institute invoked a clause of the by-laws to contest the proposal to lower the TLV for formaldehyde in 1991.
TLVs for 98 substances were criticized as insufficiently protective by the Na tional Institute for Occupational Safety and Health (NIOSH), in comments to the Occupational Safety and Health Administration (OSHA) on the "Air Contaminants" rule [Robinson et al., 1991]. By this regulation, OSHA adopted the 1987 TLVs for about 350 of the 376 substances included. The rule was adopted in the last week of the Reagan administration, in 1989, and was supported by the Chemical Manufac turers Association. OSHA's regulation was then challenged by other industrial parties and overturned in Court in 1992 [Begley and Kirschner, 1993]. TLVs and TLV assignments of 229 substances have been criticized in recent years (see Table II).
Rappaport [1993] also suggested that ACGIH consider revising its definition of
Approaches to Risk Assessement
TABLE II. TLV Assignments and TLVs That Have Been Criticized. 1988-1991* (Continued)
Substance
A B CD E
Crufomate ("Ruelene")
Cydopentadiene
Cyhexatin ("Piictran")
Dibromochloropropane
Dibutyl phthalate
p-Dichlorobenzene
Dichlorodifluoromethane
DichlorodiphenyItrichloroethane (DDT)
Dichloroethylene
Dichloromonofluoromethane
1.2 Dichloropropane (propylene dichloride)
1.3 Dichloropropene
2.2 Dichloropropionic acid
Dichlorotetrafluoroethane
Dicrotophos
Dicyclopentadiene
Dicyclopentadienyl iron
Diethyl phthalate
Diglycidyl ether
Dimethyl acetamide
Dimethyl amine
Dimethyl formamide
1.1 Dimethyl hydrazine
Dimethyl sulfate
Dinitolmide
Di-sec-octyl phthalate
Dioxane
Dioxin
Diphenylamine
Dipropylene glycol methyl ether
Disulfoton
Diuron ("Karmex")
Divinylbenzene
Endrin
Epichlorohydrin
Ethanol
.
Ethanolamine
Ethion
2-Ethoxyethano!
Ethyl acetate .
Ethyl acrylate
Ethyl amyl ketone
Ethyl bromide
Ethyl chloride
Ethylene diamine
Ethylene dibromide
Ethylene dichloride
Ethylene glycol
Ethylene oxide
X X X
X X X X X X
XX XX X
X X X X X X X X X XX
X XX XX
X X X
X X
X X XX
X XX
X X
X X
X X
X X X
XX X XX XX
X
(continued)
139
140 ACGIH: Low Threshold of Credibility
TABLE II. TLV Assignments and TLVs That Have Been Criticized, 1980*1991* (Continued)__
Substance
A BC D E
Ethylenimine
Ethyl ether
n-Ethyi morpholine
Fenamiphos ("Nemacur")
Fenthion ("Baytex")
Fluoride
Fluorine
Fonophos
Formaldehyde
Formamide
Furfural
Glutaraldehyde
Grain dust
Heptane
Hexafluoroacetone
Hexamethyl phosphoramide
Hexane isomers
Hydrazine
Hydrogen cyanide
Hydroquinone
2-Hydroxypropyl acrylate
Isooctyl alcohol
Isophorone
Isophorone diisocyanate
Isopropoxyethanol
Isopropyl acetate
Isopropylamine
n-Isopropyl aniline
Lead
'
Lead chromate
Magnesium oxide fume
Manganese dust and compounds
Manganese tetroxide
Mercury
Mesityl oxide
Methacrylic acid
Methomyl ("Lannate")
2-Methoxyethanol
4-Methoxyphenol
Methyl acetylene-propadiene mixture
Methyl bromide
Methyl n-butyl ketone
Methyl chloride
Methyl chloroform
Methyl 2-cyanoacrylate
Methylene chloride
4t4'-Methylene bis (2-chloroaniline)
Methylene bis(4-cyc!ohexyl isocyanate)
Methylene bisphenyl isocyanate
4,4' Methylene dianiline
Methyl hydrazine
Methyl isocyanate
X
X
X
xX x
X
X
X
X
X
XX X
X
X
X
X
X
X
X
X X X X X XX
X X X XX X X X XX XX XX X X XX X X X X XX XX X X XX XX X X X X X
(continued)
Approaches to Risk Assessment
TABLE II. TLV Assignments and TLVs That Have Been Criticized,
1988-1991* (Continued)
_____________________________
Substance
ABCDE
Metribuzin ("Sencor")
Mineral oil mist
Molybdenum (soluble)
Monocrotophos
Nickel, soluble or inorganic compounds
Nitrapyrin
p-Nitrochlorobenzene
Nitroglycerin
Nitromethane
2-Nitropropane
Octane
Ozone
Paraquat
Parathion
Pentane
2-Pentanone (methyl propyl ketone)
Perchloroethylene
Perchloromethyl mercaptan
Phenylene diamine
Phenyl glycidyl ether
Phenyl hydrazine
Phenyl phosphine
Phosgene
Picloram ("Tordon")
Piperazine dihydrochloride
Propionic acid
Propylene glycol methyl ether
Propylene glycol monoethyl ether
Propylene oxide
Quartz
Quinone
Resorcinol
Rosin core solder pyrol. products
Selenium
Silica, amorphous
Silica, crystalline
.
Silicon tetrahydride
Silver and compounds
Styrene
Sulfur dioxide
Sulfuric acid mist
Sulfuryl fluoride
Sulprofos ("Bolstar")
2,4,5-T
Tetraethyl lead
Tetrahydrofuran
Tetramethyl lead
Tetrasodium pyrophosphate
Thioglycolic acid
Thiram
Toluene
m-Toluene diamine
XX X X
X X
X XX
X X X X X
X X
,X X
Xx
X X
X X X X X X X X X X X X X XX X X XX X X XX X X X X X X X X X X X XX X
(continued)
141
142 ACGIH: Low Threshold of Credibility
TABLE II. TLV Assignments and TLVs That Have Been Criticized, 1988-1991* (Continued)___________________________________________
Substance
ABCD
Toluene diisocyanate m- and p-Toluidine 1,2.4 Trichlorobenzene Trichloroethylene Trichlorofluoromethane Trichlorotrifluoroethane Tricyclohexyltin hydroxide Triethylamine. Trimethyl phosphite Triphenyl amine Tris (2.3) dibromopropyl phosphate Tungsten compounds Vinyl acetate Vinyl bromide Vinyl chloride Vinyl cyclohexene dioxide Vinylidene chloride Welding fumes Wood dust, softwood m-Xylcne. a.a'-diamine Xylidine Zinc chromate Zinc oxide fume Zinc stearate Zirconium compounds
.
XX X
X XX X
X X X X
X X
X
X XX
X
X X
X
E
X X
X
x
X
X X X
X
X
*A: TLV documentation assigned to representative of manufacturer on TLV com mittee, 1970-1988 (Castieman and Ziem. 1988: Ziem and Castleman, 1989): B: TLV (1986) placed important reliance on unpublished corporate communication(s) [Castieman and Ziem, I988[; C: TLV (1986) reference articles show health effects at and below the TLVs (1986) (Roach and Rappaport, 1990]; D: Health effects at and below the TLV (1988) reported in occupational medicine journals. 1987-1989 (Ziem and Castieman, 1989]: E: TLV (1987) criticized by NIOSH as too permissive for OSHA to adopt as permissible exposure limits (Robinson et al., 1991],
TLVs to temper the assertion that the TLVs protect "nearly all workers.'' This language in TLV booklets has been misconstrued for 40 years as a guarantee of safety by some of the people the booklets were intended to serve. Its only present value is to attorneys defending companies in damage suits by reading selected sentences from the preface to the TLVs, to raise a "TLV defense" for failure to warn workers that products or practices were harmful. ACGIH leadership has resisted repeated urgings to revise the booklets' preface, to make it more realistic and internally consistent.
The concept of the TLV defense is older than the TLVs, even older than ACGIH, and was arguably one of the factors that contributed to the establishment of industrial hygiene as a profession in the 1930s. In 1935, a consortium of industrialists met to devise a comprehensive response to the "industrial dust problem," including claims demanding hundreds of millions of dollars in compensation for occupational lung disease. This led to the formation of the Air Hygiene Foundation in 1936, with 200 corporations and trade associations as members. One objective of the program of action devised was to set up "authoritative and approved standards for the control of
Approaches to Risk Assessment
143
industrial dusts which, if complied with by industries, or by industrial companies, will act as a defense against personal injury suits" [Weidlein, 1935]. Today's TLV defense asserts that: exposures in this case were thought to be below the TLVs, the TLVs were thought to be safe for workers ("based on the best available informa tion"--TLV preface), and thus what happened was not the fault of the defendant manufacturer or company hiring contract labor.
ACGIH has had 5 years to deal responsibly with criticisms of impropriety in the process for setting TLVs and has chosen to do little if anything that would inspire public trust. The organization yielded to the most recalcitrant elements on the TLV committee and on the Board of Directors in refusing to repudiate discredited proce dures and by changing as little as possible. Through the combination of intransigence and lack of resolve, ACGIH leadership has failed its members and the public once again on the TLVs. The winners in this sad affair are the business interests and lawyers that continue to use the TLVs and ACGIH's tattered credibility as a shield from liability in personal injury lawsuits.
REFERENCES
- ACGIH (1991-1993): "Documentation of the TLVs and BEls (6th Ed.)." Cincinnati: American Con
ference of Governmental Industrial Hygienists.
-
Begley R. Kirschner E (March 31. 1993): OSHA exposure limits on 400 toxins are rolled back. Chem
Week, p 14.
`
Castleman BI. Ziem GE (1988): Corporate influence on threshold limit values. Am J lnd Med 13:531
559.
E.I. du Pont de Nemours & Company (1966): Standards Section--Safety and Fire Protection Subcom
mittee Minutes of the Meeting held Tuesday. August 30. 1966. at 9:00 A.M. in Room 13418.
Nemours Building. Dated September 1. 1966.
Rappaport SM (1993): Threshold limit values, permissible exposure limits, and feasibility: The bases for
exposure limits in the United States. Am J lnd Med 23:683-694.
Roach SA, Rappaport SM (1990): But they are not thresholds: A critical analysis of the documentation
of threshold limit values. Am J lnd Med 17:727-753.
Robinson JC, Paxman EX3. Rappaport SM (1991): Implications of OSHA's reliance on TLVs in devel
oping the air contaminants standard. Am J lnd Med 19:3-13.
'Weidlein ER (1935): Plan for study of dust problems. In WG Hazard correspondence to LR Thompson,
March 21, 1935, National Archives. Record Group 90. State boards of health (0875-96-49,
. Pittsburgh). Courtesy D. Rosner and G. Markowitz. New York.
Ziem GE, Castleman BI (1989): Threshold limit values: Historical Perspectives and current practice. J
Occup Med 31:910-918.