acgih’s role in the development of exposure assessment guidelines for occupational hygiene scott...

ACGIH’s Role in the Development of Exposure Assessment Guidelines

for Occupational Hygiene

Scott E. Merkle, CIH

AIHA Carolinas Section -- Spring Conference Charlotte, NC March 13-15, 2002

Overview

• Some background on TLVs®.

• How TLVs are developed.

• The legal challenges of 2001.

• Where do we go from here?

What is ACGIH®?

• Membership Society– Multi-disciplinary– Core membership from government & academic

institutions

• Neutral on Public Positions

• No programs in credentialing, job placement, or associated business services

What Does ACGIH Do?

• Develop health-based occupational exposure guidelines.– TLVs and BEIs

• Develop practice guidelines for occupational hygiene methodology.– Industrial Ventilation and Air Sampling Instruments

TLVs® and BEIs®

• Threshold Limit Values for Chemical Substances

• Threshold Limit Values for Physical Agents

• Biological Exposure Indices for Chemical Substances

Selected Milestones in the History of TLVs/BEIs

1941 - Committee established.

1946 - First list published.

1954 - Notice of Intended Changes published.

1955 - Begin to develop Documentation for each TLV.

1962 - First Edition of Documentation published.

1968 - TLV Committee for Physical Agents appointed.

Selected Milestones in the History of TLVs/BEIs

1980 - Committee guidelines and procedures approved and published. Updated in 1987, 1989, 1992, 1994, 1998, 2001

1983 - BEI Committee appointed

2000 - Bylaws and conflict of interest policy revised to allow expanded voting privileges

2001 - Litigation defense (3 cases)

TLVs Defined

“Airborne concentrations of substances and represent conditions under which it is believed that nearly all workers may be repeatedly exposed day after day without adverse health effects.”

TLV

Core TLV Principles

• Airborne exposure values for the occupational setting.

• Health-based values.Technical, economic, and analytic feasibility is not

considered.

• Not intended for legal adoption; TLVs are not consensus standards.

Core TLV Principles

• Guidance values to be applied by persons trained in occupational hygiene.

• The “threshold” concept.

• Established to protect “nearly all” workers.

• Not appropriate for use as index of relative toxicity.

Critical Health Effect Basis for TLVs

TLV Basis - Critical Effect PercentIrritation 30.4CNS effects 12.0Respiratory effects 8.8Liver effects 8.7Blood effects 6.4Kidney effects 4.7Skin effects 3.8Cancer 3.7Sensitization 2.8All other effects 18.7

TLV Documentation• TLV -- more than just “THE NUMBER”

• Documentation describes:– Critical health effects

– Quality of the data relied upon and areas of uncertainty

– Possible sensitive subgroups

• 7th Edition issued in 2001

TLV-CS Committee Membership

OccupationalHygiene

OccupationalMedicine

Toxicology

Epidemiology

TLV-CS Committee Structure

Staff

Subcom m ittees --Substance Selection

N otationsM em bership , etc.

S taff Assistants

D ust & InorganicsSubcom m ittee

(D & I)

H ydrogen, O xygen, C arbonSubcom m ittee

(H O C )

M iscellaneous C om poundsSubcom m ittee

(M ISC O )

TLV Full C om m ittee(S teering C om m ittee)

AC G IH B oard ofD irectors

AC G IH M em bership

TLV Development Process

Under StudyList

DraftDoc.

Comm. & BoardApprovalNIC

Comm. Review& Revision

External

Input

AdoptedValue

Comm. Review& Revision

Comm. & BoardApproval

The Essential Ingredients for Developing TLVs/BEIs

Published / Peer-Reviewed Science

+

Dedicated Volunteerism

+

Professional Integrity & Judgement

Legal Challenges of 2001

In December 2000, ACGIH was named as a defendant in 3 separate lawsuits --

• The “Staples” Case -- Carlin David Staples, et. al. vs. DOW Chemical Company, et. al.– ACGIH one of many defendants. Plaintiffs allege

conspiracy to withhold information on hazards of vinyl chloride exposure.

– Case has been resolved. There are no longer any claims against ACGIH.

Legal Challenges of 2001

• The “RCFC” Case -- Refractory Ceramic Fibers Coalition, et. al. vs. ACGIH – Adoption of TLV for refractory ceramic fibers (0.2

fibers/cc, TWA)– Settled July, 2001

• The “Trona” Case -- Anchor Glass Container Corp., et. al. vs. ACGIH, U.S. DOL, and U.S. DHHS– Proposed TLV for Trona (sodium sesquicarbonate)– Settled September, 2001

Legal Issues• Free Speech (First Amendment)

– ACGIH’s Right to Publish

• Federal Advisory Committee Act– ACGIH is a Private Professional Society and not a Quasi-

Governmental Organization

• Deceptive Trade Practice & Product Defamation– Economic harm

• Due Process– TLVs/BEIs are not developed using a consensus process– Perceived promises & conflicts

Impacts of the Lawsuits• Financial

– Insurance coverage– Indirect and opportunity costs

• Volunteer Service

• Misinformation and Misperceptions– Lobby efforts to “reform” ACGIH

ACGIH

Legal Settlements• Complete resolution of issues between the parties.

• Some aspects may be confidential.

• No court judgments awarding monetary damages; All parties paid their own legal expenses.

• Public statements.

• No precedent setting value.

Lessons

• TLVs provide vitally important benchmarks for occupational exposure assessment.

• The status of TLVs as guidelines - not standards - is not understood.

• The “3 C’s” of the TLV development process.

OMMUNICATION

• Clearly established procedures for internal and external communications.

• Publicly available information sources on the TLV process and how/when interested parties can have input.

ONFIDENTIALITY

• Preliminary drafts and discussions should stay within the Committee.

• The TLV and Documentation are products of ACGIH and the Committee. The identity of individual authors should be protected.

ONFLICT OF INTEREST

• Conflicts can be actual or perceived.

• Conflicts can range from minor to significant.

• Committee members must declare all potential conflicts to their peers.

• Actions to protect the process and prevent conflicts must be consistently applied.

Where Do We Go From Here?

• TLV/BEI Operation Manuals.– Internal organization and procedures.

• AIHce Forums on TLV/BEI issues.

• TLV/BEI section on the ACGIH website, e.g.:– NIC and Substances Under Study Lists.– Procedures and timeframes for communications.

• Statement of Position.

Where Do We Go From Here?

• Specific guidelines on conflict of interest– Augments current policy– Addresses relationships involving the Private

sector, Government (regulatory), and Academia

• Retreat on long-range issues– Resource needs– Explore the possible role for external peer review &

scientific advisory panels

A Sunrise or Sunset?

• Out-dated OSHA PELs.

• Professional society role in developing practice guidelines.

• Promises & pitfalls of the consensus process.

• Will future be driven by tort and product liability?

• Our role in protecting worker health.