The Seven Deadly Sins of Environmental Health Research

Philippe GrandjeanUniversity of Southern DenmarkHarvard School of Public Health

… and the Precautionary

Virtues

… probably more widely known from modern action moviesthan from environmental epidemiology

The seven main attitudes that underlie sinswere first identified by St. John Cassian (360 - 435) and refined by Pope St. Gregory the Great (540 - 604)

”A very partial list”Aviad KleinbergProfessor of History, Tel Aviv University

Dante’s Mount Purgatory

…and a modern version

Superbia (pride) Self-delusion, grandiose illusions Paying overzealous attention and pious

respect to high scientific standards … when judging the work of colleagues

Condescending attitude toward studies from other countries or cultures

AJPH 2001;91:1749-57

Pride ignores the bias in epidemiology conclusions*

Methodological feature Main direction of errorLow statistical power False negativeUse of 5 % probability level False negativeUse of 20% probability level to minimize risk of type II error False negative

Post hoc hypothesis False positivePressures against false alarm False negativePublication bias False positiveetc…

Developed with David Gee, EEA, and Collegium Ramazzini colleagues

“All scientific work is incomplete…All scientific work is liable to be upset or modified by advancing knowledge. That does not confer upon us the freedom to ignore the knowledge we already have, or to postpone the action that it appears to demand at the given time.”

A Bradford Hill (1965)

Envious researchers mistake the validity of their own conclusions for meticulousness in identifying presumed violations of causal “criteria”

Ingratitude and failure to recognize others’ achievements Abusing “criteria” for causality

Invidia (envy)

UCSF Brown & Williamson Documents

Impartiality in scienceResearchers (and their sponsors) may try to strengthen their own views by pointing out presumed violations of causal “criteria”…

…but failure to satisfy such formal criteria provides little support for the absence of a causation

… when rejecting the evidence

[There is] still no positive proof of a causal relationship between the use of thalidomide during pregnancy and malformations in the newborn… [and it is] encouraging to note that studies in pregnant rats have not shown a single malformation in more than 1,100 offspring of thalidomide-treated animals.

Frank N. Getman, President, William S.Merrell Co. (1962)

Injury is transformed into the pleasure of vengeance

Often coupled with narrow-minded inflexibility

Ira (Wrath)

Gula (gluttony): Endless replication creates inertia and constipation

• The majority of published papers in environmental health journals deals with a limited, rather stable list of pollutants

• PubMed lists over 15,000 scientific publications on lead – endless repetition?

• At the same time, PubMed lists very few papers on, e.g., perfluorooctane sulfonates

• Such discrepancy may be justified only if lead constitutes a paradigm (which is applied)

Gluttony: Demand of full

documentation, complete evidence

and Lust: Desire for prestige

and publications

…pave the way for continued studies,

more funding

… Greed

Lust and greed may be explored by vested intereststo short-cut researchin health and environment

Biasing the choices of study topicsHiding unwanted data Tainting the conclusions

”Doubt” is our product(Brown and Williamson, 1969)*

*Glantz SA et al.The cigarette papers. Berkeley: UC Press, 1996, p. 171. From AJPH

Acedia (sloth)Indifference to the welfare of othersApathy, callousness and lack of caringHiding in the ivory tower

0

100

200

300

400

500

600

700

1960 1970 1985 1991

Year when CDC action limit was changed

Blo

od-le

ad c

once

ntra

tion

(µg/

L) Safe level now recommended by many public-health officials

Truly safe level

Sloth: Committing Type III errors by studying the wrong (though convenient) parameters

70% of Americans own running shoes but don’t run

What would Dante have suggested?

In interpretingenvironmental research,we must recognize that a phenomenonmay exist, even if we cannot see it:

What could be known,given our research opportunities and methodologies?

The Precautionary Principle• In situations of potentially serious or irreversible

threats to health or to the environment, the need to act to reduce potential hazards before there is strong proof of harm, should take into account likely costs and benefits of action and inaction

• Introduced as the ‘Vorsorgeprinzip’ in social context in Germany during the early 1930s

• Formally extended to environmental policy during about 1970 as a planning instrument

• The modern PP was born and included in the first convention on protection of the North Sea in 1984 and is now part of the EU treaty

Scientific understanding

Risk assessment

Precautionaryprinciple

Complexity of problem

Use

fuln

ess

of a

ppro

ach

Becomes less usefulwhen incertitude increases

Complements risk assessmentwhen incertitude increases

The virtues must address…

The limitations to epidemiologic evidence

Conclusions being provisional and temporary

The impact of uncertainties

Worst-case scenario, not just null hypothesis

Facilitating application of the “Precautionary Principle” in decision-making

Precautionary virtues needed to counterbalance the deadly sins

Time / Degree of scientific certainty

Ext

ent o

f com

mun

ity re

spon

se

Initial research

Stakeholderinvolvement

Focusedresearch

Precautionaryaction to

protect groupsat high risk

Precautionarymonitoring of

suspectedexposures

Risk assessment

Evidence-basedaction

The Science-Policy Gap: Proposal for a Bridge

Prudent interpretation of epidemiology may be inspired by, but does not depend on, the Precautionary Principle The subject is capable of being decided by exact numerical investigation, but I have thought it better to publish my inquiry in its present imperfect state than to wait till I should be able to make such a complete research as I could wish, more especially as, by directing the attention of the profession to the question, it may be earlier decided.

John Snow (1855)

What an individual is capable of may be measured by how far his understanding is from his willing. What a person can understand he must also be able to make himself will. Between understanding and willing lie the excuses and evasions.

Kierkegaard

Virtues inspired by the Precautionary Principle

• Provide the best possible input to decision-making and application of the precautionary principle

• Accept and explore uncertainties and their implications• Take into consideration what could be known given the

current research insights and opportunities• Absence of evidence should not be taken as evidence

of absence of a hazard• Science planning and reporting is part of a dynamic

interface with decision-making and intervention• Include open discussion with stakeholders

Vice Precautionary virtue

Pride Preoccupation with methodology

Humility Exploration of uncertainty

Envy Failure to recognize achievements by others

Fairness What could be known, given the evidence?

Wrath Self-righteous intimidation of competitors

Empathy Weighing in all relevant evidence

Precautionary remedies for ailing epidemiology

Vice Precautionary virtue

Lust Desire for academic honors

Restraint Balanced choice of research methods/topics

Gluttony Excessive craving for publications

Innova-tion

Limiting attempts of replication

Greed Benefit from vested interests

Trans-parency

Involvement of all stakeholders

Sloth Callousness to injustice

Com-passion

Public health responsibility

Expunging sins

Precautionary thinking …in planning, conducting, analyzing, and reporting

Lust 35%

Anger 18%

Pride 12%

Sloth 10%

Envy 10%

Gluttony 9%

Greed 6%

Poll: Of the seven deadly sins, this ONE is my biggest failing:

The ”new” sins• Genetic modification • Human experimentation • Polluting the environment • Social injustice • Causing poverty • Financial gluttony • Taking drugs

Environmental Researchers’ Paradise

Ascent facilitated by precautionary virtues

(substantially) revised from Dante Alighieri (1265-1321), with apologies

To expunge their sinsresearchers must climbMount Purgatory Pride

EnvyWrath

GreedGreed Lust

GluttonySloth