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Epidemiologic Techniques: How to Hide a Benzene Cancer Relationship: You can’t regulate if the Companies Lie. A case study of Shell’s Benzene Historical Exposure Study (BHES). Based on documents produced in toxic tort discovery
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Epidemiologic Techniques: How to Hide a Benzene Cancer Relationship:You can’t regulate if the Companies Lie A case study of Shell’s Benzene Historical Exposure Study (BHES) Based on documents produced in toxic tort discovery The view expressed here are those of the authors; the documents are available for review at: http://egilman.com/browse.php?display=list&dir=benzene_apha/
Science denied Benzene first reported as toxic Early 1900s OSHA announces plans for new PEL by 1984, accepting evidence Shell Oil BHES publication #1 Shell Oil presents findings to OSHA Shell Oil quickly conducts Benzene Historical Exposure Study (BHES) OSHA collects enough evidence to reinstate 1 ppm PEL Shell Oil BHES publication #2 Challenge by allied petroleum industry stays then overturns new PEL OSHA attempts to lower Benzene PEL from 10 ppm to 1 ppm Infante et al. published first cohort study assessing benzene/leukemia 1987 1978-80 1986 1985 1983 1984 1983 1978 1977 American Petroleum Institute says “Only safe concentration is zero.” 1948 1987 on – Shell continues to publish data follow-ups of faulty BHES study. 1987 through 2006 – liability cases for occupational benzene exposure in courts.
Means more workers die Challenge by allied petroleum industry stays overturns lower PEL OSHA collects enough evidence to reinstate 1 ppm PEL 1978-80 1987 Estimated 30-490 extra deaths from this regulatory delay.
Benzene & Shell refineries Used in gasoline refinery processes Frequent addition to chemical blends Used as cleaning solvent, esp. during 1940s-50s. Benzene is understood to be a causal agent for Acute Myelogenous Leukemia (AML)
Shell refineries with excess deaths • Wood River Manufacturing Complex (WRMC) & Deer Park Manufacturing Complex (DPMC) • Elevated leukemia rates noted in mid-1970s as a result of a contractor worker lawsuit for compensation.
Methods Never admit a fault or wrong; Never leave room for alternatives; Never accept blame; People will believe a big lie sooner than a little one; and If you repeat it frequently enough people will sooner or later believe it. -Ludecke “I Knew Hitler”
How to Hide…Step 1 Never admit a fault or wrong Reassure everyone that there’s no evidence
The Lie – AP Wire Press Release 1983 Shell has found no link between benzene and the relatively high incidence of deaths from a certain type of leukemia in Texas & Illinois plants that handle the chemical
How to Hide…Step 2Repeat the Lie Report new (and flawed) evidence that shows “no relationship” between benzene and cancer
1984 Lie to OSHA/NIOSH Our analysis has nevertheless failed to establish a causal relationship between benzene exposure and AML.
1984 letter to OSHA/NIOSH • Basis of “no causal relationship” was the report that 9 of 23 leukemia cases had “nil” exposure to benzene at the plants. • Plus cases didn’t cluster in highest exposure jobs. • Exposure estimates were based on reconstructed histories of work locations + peer interviews.
From a related study -You can fool some of the people…1983 “It must be recognized that this study’s negative result will generally be perceived as not highly persuasive” because.. Benzene, being highly volatile, may permeate nearly the entire facility and affect just “susceptible” individuals.”
Methods: Never leave room for alternatives Exposure assessments based on smell “I fear we will be seriously underestimating the exposure” Omitted from papers
Methods: Never leave room for alternatives The suggestion has been made previously that existing and available extensive leak rate data on petroleum refineries be combined with air pollution dispersion modeling techniques…The notable lack of enthusiasm among your experts concerns me. Rejected
Worker Exposures “disappeared” • There was little evidence on exact worksites of people assigned to refinery-wide jobs such as laborer or carpenter. • This meant there was no basis to establish ‘nil’ exposures Nil = nothing; naught; zero, having no value or existence
The Truth - Worker Exposures “disappeared” The 7 “nil” exposure cases (refinery-wide workers) were either probably or definitely exposed
“None determinable” becomes “Nil” BUT: “I do not know” ≠ “Zero”
The Truth - Worker Exposures “disappeared” Wood River leukemia cases had a combined total of 164 years assigned to “refinery-wide” positions. You cannot say “subjects did not work in jobs identified as having the highest benzene exposures” if you don’t know where they worked!
Worker Exposures “disappeared” In a minimum of 4 cases, Shell ignored evidence of benzene use as a cleaning agent.
Worker Exposures “disappeared” Accounting for direct use of benzene as a cleaning agent (highest exposure level) would have shattered the claim that people with AML didn’t work in the highest exposure jobs.
Published LIE“ONLY ONE≠ NONE Cole P, McCraw D, Joyner R. Brief Communication: Excess Leukemia in a Refinery Population. JOM 1985/3/1;27(3):220-222. “This investigation has shown that the subjects did not work in jobs identified as having the highest benzene exposure” “Five [of the leukemia cases] spent most of their years as maintenance [Laborer] workers, but it is not known if they were ever assigned to benzene units.”
Data: “ONLY ONE≠ NONE “Of potential significance is that the highest exposure jobs are not reflected in the work records of the diagnosed leukemia case. For example only one [a maintenance worker] of the Wood River cases worked in the highest exposure jobs related to the Cumene Plant”
How to Hide…Step 3 Populate the peer literature with articles repeating the point Repeat the lie as often as possible
Repeat the Lie - 1986 Austin H, Cole P, McCraw D. A Case-Control Study of Leukemia at an Oil Refinery. Journal of Occupational Medicine. 1986/11/1;28(11):1169-1173. • Incorporated same design flaws as earlier SMR study • Incorporated personnel misclassification errors, biasing outcome to the null • Key personnel were not blinded – invalidating study “Thus the reason for the excess leukemia at this refinery was not identified.”
Repeat the Lie - 1989 Wongsrichanalai C, Delzell E, Cole P. Mortality from leukemia and other diseases among workers at a petroleum refinery. J.Occup.Med. 1989/2;31(2):106-111. • Mortality study on WRMC population • They admit a statistically significant elevated risk for leukemia at plant • But argue against a benzene relationship • Why? Key reason is Shell’s earlier two studies showed none “Several observations argue to some extent against the hypothesis that the excess [leukemia] is due to refinery [benzene] exposures.”
Eliminate the - 1995 Honda Y, Delzell E, Cole P. An updated study of mortality among workers at a petroleum manufacturing plant. J.Occup.Environ.Med. 1995/2;37(2):194-200. • Update of 1989 mortality study, checking to see if excess leukemia is now disappearing. • Study incorporated systemic misclassification errors. • Published study excluded relevant negative findings from the internal version. “These results indicate that any occupational leukemogenic exposures at the plant have been reduced to the point where they are insufficient to cause leukemia.”
How to Hide a Benzene Cancer Relationship • Reassure everyone that there’s no evidence • Report new (flawed) evidence that shows “no relationship” • Populate the peer literature with articles repeating the point
Disclosures and contact • Financial disclosure statement • D. Egilman consults at the request of lawyers representing patients with AML who have had benzene exposure. • Correspondence to: David Egilman, MD, MPH 8 North Main Street Suite 404 Attleboro, MA 02703 508-226-5091 Authors: D. Egilman, Scout, L. Kol, S. Bohme