Document ID: OSHA-2008-0046-0021
Agency: osha
Document Type: Supporting & Related Material
Title: 
Posted Date: 2009-02-19T05:00Z

Diacetyl and Food Flavorings Containing Diacetyl Stakeholder Meeting Notes  
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            Diacetyl and Food Flavorings Containing Diacetyl

            Stakeholder Meeting
            Arlington, Virginia
            October 17, 2007

            Meeting Summary Report

            Draft - Version Date November 27, 2007

            Table of Contents

            1   Meeting Format

            2   Introduction

            3   Questions and Comments to OSHA from Stakeholders

            4   Questions from OSHA to Stakeholders

            5   Closing Remarks

            Diacetyl and Food Flavorings Containing Diacetyl

            Stakeholder Meeting
            Arlington, Virginia
            October 17, 2007
            Meeting Summary Report

            1     Meeting Format 

            As part of the OSHA process to gather information about the 
            occupational exposure to diacetyl and food flavorings containing 
            diacetyl, OSHA hosted this stakeholder meeting focusing on butter 
            and other food flavorings containing this substance. OSHA 
            specifically sought information regarding uses of diacetyl and food 
            flavorings containing diacetyl, medical screening and surveillance 
            for workers exposed to these substances, and diacetyl exposure 
            assessment and control methods.  OSHA representatives and 
            stakeholders participated in an open conversation not only to 
            address specific OSHA information requests, but also to identify 
            stakeholder concerns associated with developing interim and final 
            rules on occupational exposure to diacetyl and food flavorings 
            containing diacetyl.

            The following is a summary of the key comments stakeholders made 
            during that meeting. Comments are grouped together by topic, without 
            reference to the identity of the speakers.

            2     Introduction 

            OSHA representatives provided background information on the 
            enforcement and compliance actions taken by OSHA to address the 
            hazards associated with occupational exposure to diacetyl and food 
            flavorings containing diacetyl, OSHA's authority to regulate 
            employee exposure to these substances, and the OSHA stakeholder and 
            standard-setting process.

            OSHA enforcement and compliance activities in the past six years 
            have included investigations by regional OSHA offices and 
            development of publications targeting microwave popcorn facilities 
            and employers. Additionally, a National Emphasis Program aimed at 
            minimizing or eliminating employee exposure will result in 
            inspections of microwave popcorn manufacturing facilities that use 
            butter flavorings containing diacetyl.  Other efforts include (1) 
            development of a Safety and Health Bulletin (SHIB) that addresses 
            respiratory disease among employees in microwave popcorn processing 
            plants, and (2) the Hazard Communication Guidance for Diacetyl and 
            Food Flavorings Containing Diacetyl, which addresses 
            responsibilities of flavoring manufacturers and employers who must 
            comply with OSHA's Hazard Communication Standard with regard to 
            diacetyl and food flavorings that contain diacetyl.

            In response to a petition to issue an emergency temporary standard 
            (ETS), OSHA's Directorate of Standards and Guidance (DSG) carefully 
            reviewed the existing data.  This review did not support the 
            issuance of an emergency temporary standard (ETS) under Section 6(c) 
            of the Occupational Safety and Health Act of 1970 (OSH Act) (29 
            U.S.C. 651 et seq.) to protect employees from a grave danger due to 
            exposure.  Hence OSHA will develop an occupational health standard 
            addressing the likely significant risk of material impairment of 
            health due to exposure to diacetyl and food flavorings containing 
            diacetyl under Section 6(b) of the Occupational Safety and Health 
            Act.

            Since receiving the petition for an ETS, OSHA's DSG has undertaken 
            several activities to understand the scope of the hazard and the 
            rapidly evolving information about diacetyl and food flavorings 
            containing diacetyl.  Through site visits to flavor manufacturing 
            and microwave popcorn facilities, OSHA is gathering information on 
            production processes, worker exposures, and control methods.  In 
            addition, OSHA representatives described several collaborative 
            efforts to assist in their rulemaking process including: (1) ongoing 
            dialogue with the California Department of Industrial Relations' 
            Division of Occupational Safety and Health (Cal/OSHA) to better 
            understand its proposed rule to address occupational exposures to 
            food flavorings, (2) reviewing data collected by Cal/OSHA through 
            the voluntary flavoring industry safety and health evaluation 
            program (FISHEP), and by the National Institute of Occupational 
            Health and Safety (NIOSH), and (3) working with National Jewish 
            Medical Research Center to discuss their study of flavor 
            manufacturing facilities.  OSHA acknowledged the contributions and 
            support of these organizations to the rulemaking process.

            OSHA representatives also described the process for developing 
            standards.  This process typically begins with data gathering 
            efforts, such as publishing requests for information, holding 
            stakeholder meetings, and conducting site visits.  After gathering 
            information, OSHA drafts a proposed standard and evaluates the 
            potential economic impacts of the proposed rule on employers, 
            particularly small businesses.  OSHA then publishes the proposal for 
            public comment.  To gather further information and address issues 
            raised by stakeholders in their written comments, OSHA often holds 
            informal public hearings.  OSHA prepares the final rule based on all 
            the information and comments in the record.  The rulemaking process 
            includes multiple opportunities for formal and informal stakeholder 
            input.

            OSHA representatives emphasized that OSHA is in the stage of 
            gathering information on diacetyl and food flavorings containing 
            diacetyl to better understand the issues involved.  This stakeholder 
            meeting serves as an informal, conversational forum for relationship 
            building and information sharing between OSHA and stakeholders who 
            are experts in the flavorings and popcorn industries.  OSHA 
            considers stakeholder input to be extremely important in helping 
            develop an effective standard that addresses the key elements 
            associated with exposure to diacetyl and food flavorings containing 
            diacetyl, while considering the complex constitution of flavoring 
            mixtures, the proprietary nature of flavorings, and the feasibility 
            concerns of this standard.  A team of industrial hygienists and 
            economists will assist OSHA in conducting site visits and developing 
            the feasibility analysis.

            3     Questions and Comments to OSHA from Stakeholders 

            During the open conversation between OSHA representatives and 
            stakeholders, the stakeholders raised questions and concerns about 
            the rulemaking process and the use of other available datasets 
            besides the three (Cal/OSHA, NIOSH, National Jewish Medical Center) 
            mentioned by OSHA.

            3.1     How will OSHA proceed with rulemaking on diacetyl and food 
            flavorings that contain diacetyl so that process is not stretched 
            over many years, as has occurred with beryllium, silica, and 
            chromium?

            Some stakeholders expressed concern over structural impediments 
            inherent in OSHA's rulemaking process that would lengthen this 
            process.

            Several stakeholders also emphasized the importance of rapidly 
            obtaining the information needed to develop a standard.  These 
            stakeholders noted that workers continue to fall sick and suffer the 
            large social and family costs of the disease, while employers and 
            agencies debate rules and processes.  The slow response from 
            regulatory authorities and employers is disheartening for sick 
            workers who continue to be exposed or have lived with their disease 
            for many years, up to 9 years in some cases, and are still waiting 
            for decisive action. Stakeholders stated that employers and 
            regulatory agencies should put worker interests at the forefront of 
            the debate.

            OSHA representatives emphasized that the diacetyl rulemaking is 
            considered a priority for OSHA and the process is being expedited to 
            the full extent possible.  OSHA understands the importance of 
            developing a standard quickly due to the impact exposures to 
            diacetyl and food flavorings containing diacetyl have on workers.  
            OSHA is committed to keep the process moving through all the 
            necessary stages of rulemaking as required under OSHA mandate.

            3.2     Is there a timetable for the rulemaking process? 

            Some stakeholders noted that a timetable for the rulemaking process 
            would greatly reassure stakeholders of OSHA's intent and plan to 
            move expeditiously.  A stakeholder requested that the timetable 
            include a schedule listing periods during which OSHA will accept 
            comments and stakeholders may provide OSHA with responses.  It was 
            also suggested that stakeholders be allowed to contribute to the 
            agendas for public meetings and the rulemaking process.

            OSHA noted that the regulatory agenda, published in the Federal 
            Register, serves as a public timetable of milestones in the 
            rulemaking process and is updated every 6 months.

            3.3     The length of traditional OSHA regulatory process is not 
            expected to produce the desired result in the timeframe needed.  
            Hence, given that the State of California is currently developing a 
            standard for occupational exposures to food flavorings, OSHA would 
            greatly benefit from working collaboratively with Cal/OSHA instead 
            of developing a separate process.

            A few stakeholders observed that OSHA should examine the entire 
            rulemaking process.  In light of the short-term latency issues 
            associated with flavoring-related obstructive airway disease, they 
            urged OSHA to consider creative means to expedite the rulemaking 
            process, such as obtaining data collected by other agencies and 
            organizations with similar aims.  A stakeholder noted that Cal/OSHA 
            has similar statutes as OSHA and that a joint effort should be 
            considered.

            An OSHA representative pointed out that the agency must work within 
            its requirements for rulemaking and that the analytic burden and 
            feasibility requirements for Cal/OSHA are different compared to 
            those at the federal level.  However, OSHA is open to new methods of 
            obtaining data more quickly.  OSHA will work collaboratively with 
            Cal/OSHA and NIOSH to take advantage of the progress these 
            organizations have already made with respect to understanding 
            diacetyl and food flavorings containing diacetyl.  OSHA has already 
            committed contract resources to help compile the Cal/OSHA data.

            Two stakeholders commented that the analytic burdens on OSHA are 
            excessive.  They also stated that even though the OSHA and Cal/OSHA 
            regulatory processes are different, the hazard is the same and OSHA 
            should utilize the consensus that has already been built on certain 
            types of information.  For example, even though limited information 
            is available from the food manufacturing industry, the consensus 
            developed by the microwave popcorn and flavoring manufacturing 
            industries should be used.  Stakeholders also urged OSHA not to 
            consider the rulemaking process merely a legal checklist, but 
            instead to develop a consensus process, even if this process differs 
            from the traditional OSHA rulemaking process.

            3.4     Does OSHA have data from the U.S. Environmental Protection 
            Agency (EPA) study?

            OSHA representatives responded that they had inquired about the 
            availability of the EPA study and were told that a study report was 
            under industry review to ensure that it did not contain confidential 
            business information.  OSHA representatives indicated that the 
            agency would continue to seek the study results.  [OSHA finally 
            received the study report in early November].  OSHA representatives 
            also observed that the Cal/OSHA and NIOSH studies were more relevant 
            for the OSHA rulemaking effort, as these studies focused on 
            occupational exposures to food flavorings containing diacetyl, 
            unlike the EPA study which studied emissions from popcorn bags.

            One stakeholder emphasized the importance of the EPA study since 
            this study addresses emissions of diacetyl and other butter 
            flavoring compounds from microwave popcorn.  The stakeholder 
            encouraged OSHA to obtain the results of the study by formal means, 
            such as via a formal letter of request from the Assistant Secretary, 
            if necessary.

            3.5     A strong need exists for obtaining information as quickly as 
            possible.  The slow response from regulatory authorities and 
            employers is disheartening for sick workers who continue to be 
            exposed or have lived with their disease for many years.

            A few stakeholders observed that many developments have taken place 
            in the past 7 to 8 years and many large companies have already taken 
            steps to institute controls that protect workers.  In other cases, 
            some companies may not have made as much progress due to a lack of 
            resources, understanding, or interest.  These companies might be 
            looking for guidance from government agencies before acting.

            3.6     Why does OSHA's hazard communication guidance not reference 
            the latest Mortality and Morbidity Weekly Reports (MMWR) or the 
            California cases/studies?

            OSHA representatives explained that the process for developing and 
            reviewing hazard communication guidance is often stretched over 
            several months.  Hence, the information in the guidance may not 
            always reflect the most recent findings.  OSHA will have 
            opportunities to update the guidance document in the future and will 
            incorporate new information.

            One stakeholder also commended OSHA on developing its hazard 
            communication guidance, which was very useful.

            4     Questions from OSHA to Stakeholders 

            OSHA representatives sought specific information regarding the uses 
            of diacetyl and food flavorings containing diacetyl, effective means 
            of conducting medical screening and surveillance, exposure 
            assessment techniques, and exposure control methods.

            A.     Uses of Diacetyl and Food Flavorings Containing Diacetyl 

            OSHA sought information on products made with diacetyl-containing 
            flavorings, production processes that use these flavorings, 
            variability of flavoring formulations, and worker exposures to 
            diacetyl and food flavorings that contain diacetyl.

            4.1     What are the uses of diacetyl and flavorings that contain 
            diacetyl? What is the universe of operations and compounds that use 
            diacetyl?  What are the uses of diacetyl in the flavoring and food 
            manufacturing industries besides the microwave popcorn industry?  
            What is the extent and type of diacetyl use in snack foods, bakery 
            goods, and the dairy industries?

            Stakeholders provided the following comments and recommendations 
            regarding the uses of diacetyl: 
              Diacetyl is a naturally occurring substance in many foods, such as 
              butter, strawberries, and other dairy products and fruits.  Hence, 
              food manufacturers use diacetyl to provide the same flavor 
              perception of butter in margarines and to mimic the natural 
              flavors of dairy products, fruits, and vegetables in a variety of 
              foods.  Diacetyl is generally used in low levels (tens of parts 
              per million [ppm] or less) in foods other than butter-flavored 
              items and popcorn.  Diacetyl typically represents less than one 
              percent of the flavor product that leaves the plant and is shipped 
              to food manufacturers.  Occupational exposures differ between the 
              flavorists involved in manufacturing the flavoring substance, the 
              food producers who use the flavors in food manufacture, and 
              consumers. Several stakeholders were willing to provide 
              information to OSHA on the wide variety of diacetyl uses in flavor 
              and food products.

              Diacetyl appears to be a key contributor to an adverse health 
              effect.  However, no clear information exists on the contribution 
              of other components of the flavoring mixtures (such as acetoin and 
              various aldehydes) to adverse effects.  Due to the proprietary 
              nature of flavoring formulations and the complex mixtures involved 
              in flavorings, identifying specific constituents is difficult. 
              This issue requires further discussion. 

            4.2     Are there differences between the use of powdered and liquid 
            diacetyl?  Does the difference in the form of diacetyl result in 
            different exposures?  Are certain exposure levels associated with 
            handling certain products?  Should OSHA be concerned about other 
            chemicals used with diacetyl in flavoring mixtures?  Is there data 
            available that will help OSHA determine if a certain level of 
            diacetyl is associated with health effects?

            Stakeholders provided the following comments and recommendations 
            regarding the exposure potential of diacetyl:

              The opportunity for exposure is greater in the flavor 
              manufacturing industry compared to the food manufacturing industry 
              because workers handle large quantities of relatively pure 
              chemicals.  Additionally, flavor production workers handle 
              different chemicals on different days compared to food 
              manufacturing workers who tend to work with the same food item 
              every day.  Diacetyl usually represents approximately one percent 
              of the flavoring mixture, but often the levels are lower.

              Studies in a test chamber were conducted to look at the amount of 
              diacetyl released from various liquid, dry and wetted forms of 
              diacetyl.  The three forms studied included a dry powder 
              encapsulate composed of 1 to 2 percent diacetyl by weight, 
              paste/liquids composed of 4 to 9 percent diacetyl by weight, and 
              dry encapsulated powder moistened to mimic powder in contact with 
              mucous membranes of the respiratory tract.  These three forms were 
              individually placed in a chamber, and then exposed to heat (104 
              degrees Celsius [C]) and humidity that mimic plant conditions.  
              The study showed that all forms emitted diacetyl, with the 
              moistened dry encapsulated form releasing the highest quantity at 
              54 ppm diacetyl in the static head space of the test chamber.  The 
              paste/liquid form also emitted higher amounts of diacetyl than the 
              dry formulation.  This data will be provided to OSHA, as 
requested.

              Heat is an important element contributing to the exposure 
              potential of diacetyl.  Diacetyl is not typically a volatile 
              material unless heated, such as occurs in flavor manufacturing. 
              The boiling point is 88 degrees C.

              One stakeholder claimed to be aware of a clinical case that may be 
              associated with pure diacetyl.

              The same stakeholder stated that formulations have occasionally 
              been released in legal proceedings involving worker cases.  Hence 
              proprietary formulation information may be available if requested.

              Another stakeholder emphasized that worker activities that 
              facilitate exposure are as important as the product being handled 
              by the worker.  Frequency of exposure, work processes, and levels 
              of exposure should all be considered, as should worker lung 
              function and health status of workers.

            4.3     How can OSHA obtain information on how often workers are 
            exposed, what the work processes are, and what the exposure levels 
            are?  Are there potential obstacles to obtaining this type of 
            information? Stakeholders provided the following comments and 
            recommendations regarding the availability of data on worker 
            exposures to diacetyl:

              Every major manufacturer is evaluating data related to diacetyl 
              and conducting employee exposure assessments.  Thus, OSHA should 
              be able to obtain these data requested.  As some stakeholders 
              suggested to OSHA in December 2006, one means of obtaining the 
              information is a formal request by the Assistant Secretary to the 
              companies.  The stakeholders' general consensus was that OSHA 
              should not be hesitant about requesting data from industry.

              Some stakeholders emphasized the need to focus on the tasks that 
              present opportunities for exposures.  The flavor manufacturing 
              industry has a lot of valuable data that have already been 
              provided to Cal/OSHA, the California Department of Health Services 
              (Cal/DHS), and to OSHA consultants.  In addition, some other 
              datasets exist that have not yet been made available to OSHA.  A 
              few stakeholders showed a willingness to share exposure 
              information with OSHA.

              Several stakeholders believe Cal/DHS plans to make all its data 
              publicly available on its website.  Cal/OSHA has developed a 
              questionnaire designed to obtain information from the food 
              manufacturing industry.

              One stakeholder also suggested that OSHA create a disease 
              reporting registry on the OSHA web site.  Currently, there are 
              reported cases distributed across many regions of the country and 
              physicians do not have a consolidated reporting medium.  The 
              beryllium registry would be a good model for such an effort.  In 
              addition, the stakeholder suggested the disease registry would 
              help in designing much needed clinical trials and therapeutic 
              interventions.

              One stakeholder also suggested that occupational histories 
              retained by some lung transplant centers, of which only few exist 
              nationwide, could be tapped as a potential source of information 
              on potential disease cases related to diacetyl and food flavorings 
              containing diacetyl.

              A few stakeholders noted that material safety data sheets (MSDSs) 
              frequently do not include detailed information on flavorings 
              because the flavoring constituents are proprietary. Some smaller 
              food manufacturers, therefore, might not be aware of exposures 
              concerns.  OSHA representatives noted that the hazard 
              communication guidance was published in order to alert such small 
              companies of the issue.

              Some stakeholders emphasized the need to use a broad-based 
              approach in evaluating all the chemicals used in flavorings, not 
              merely focusing on diacetyl, and to study how workers are actually 
              exposed.

            4.4     OSHA plans to conduct site visits through contractors to 
            help OSHA better understand the processes involved with use of 
            flavorings containing diacetyl and how workers are exposed in 
            various industries and operations.  OSHA encouraged suggestions and 
            support from stakeholders to facilitate these site visits. 
            Stakeholders provided the following comments, questions and 
            suggestions regarding OSHA site visits to establishments that use 
            diacetyl or flavorings containing diacetyl:

              Several individual stakeholders thought that site visits may be 
              facilitated in several ways: 1) by employing a voluntary, 
              collaborative model, such as the one used by Cal/OSHA, to involve 
              almost all the flavor manufacturers; 2) by using the OSHA 
              enforcement and consultation tools and NIOSH capabilities as part 
              of an overall strategy to obtain information from food 
              manufacturers; 3) by following the model of an existing industry 
              effort to encourage medical surveillance programs in flavor 
              industry facilities (which has brought medical and health and 
              safety professionals into facilities) and expanding the effort to 
              include flavor manufacturers' food industry customers; 4) by using 
              OSHA's  regulatory authority to access employee health and 
              exposure information; and 5) by using other existing OSHA 
              collaborative agreements like VPP to contact members who will be 
              more receptive to OSHA.  Some stakeholders also suggested 
              publicizing on OSHA's website the names of companies that refuse 
              to provide OSHA with site visit opportunities.

              OSHA representatives emphasized past successes through voluntary 
              cooperation with sites.  OSHA hopes to use a similar approach in 
              its site visits rather than using an authority-driven forceful 
              inspection approach.  Some stakeholders believed that forceful 
              entry may be a more effective means of visiting a greater number 
              of food plants, since food manufacturing industries use flavorings 
              in the same way every day, which minimizes the need for scheduling 
              visits in advance.  Food manufacturing plants are typically harder 
              to enter because they are only 5 to 10 percent unionized.  
              Cooperative site visits are likely to work better with the popcorn 
              and flavoring industries.

              Some stakeholders expressed concern that OSHA's data gathering 
              inquiries were unfocused.  One stakeholder summarized these 
              concerns, urging better organization and specific identification 
              of which operations would be observed, what flavorings would be 
              targeted, what type of sampling would be performed, and how OSHA 
              intended to use the information.  This type of information would 
              be helpful in encouraging members of trade organizations to 
              cooperate more readily.  The stakeholder was willing to assist 
              OSHA and its contractor in focusing the site visit protocol.

              Some stakeholders asked whether OSHA would be willing to share 
              data with industry prior to development of the standard so that 
              the data can be used by companies to proactively develop 
              protections for workers.

              It was also suggested that company medical records (e.g., 
              spirometry) be reviewed as part of site visits. However some 
              obstacles to using such data include (1) most of the lung function 
              (spirometry test) data are not of particularly high quality, 
              although they might have some value in identifying patterns, (2) 
              the disease has a short latency period, and (3) broad-based and 
              well thought out case definitions are needed.

            B.     Medical Screening and Surveillance 

            OSHA solicited information on the scope and frequency of medical 
            surveillance, the content of a medical evaluation, and the potential 
            actions that would be triggered by medical screening findings.

            4.5     Which employees should be included in the medical 
            surveillance program? Stakeholders provided the following comments 
            and suggestions regarding the types of workers who should be 
            included in a medical surveillance program: 

              In the flavor manufacturing industry, it was suggested that 
              several groups of employees would be potential candidates for 
              medical surveillance.  These include (1) workers who mix and blend 
              liquids and powders who will be exposed to pure flavoring 
              chemicals; (2) workers who help in packaging flavoring products, 
              particularly powdered flavorings; (3) workers who clean vessels; 
              (4) quality assurance technicians and laboratory flavorists who 
              design flavors, although their exposure might be lower than the 
              production workers who blend or package large batches of these 
              products; and (5) office and clerical staff who work in production 
              areas.  All these employees should be in the medical surveillance 
              program.

              In industries that receive products from the flavoring industry, 
              monitoring workers involved in unpacking the flavoring powders was 
              suggested.

              Other groups of workers who may not actively handle flavorings, 
              but nevertheless are exposed because their jobs bring them into 
              contact with diacetyl products, include supervisors and 
              maintenance workers.

              It was noted that while some facilities may have as many as 50 to 
              75 workers; others may only have 2 workers.

              A concern was raised about the large number of temporary or 
              contract workers who work in the food manufacturing industry and 
              are often treated differently with respect to respiratory 
              protection and medical evaluation.  These workers might be part of 
              the vulnerable population who are potentially exposed but may not 
              receive appropriate protection or surveillance.  Some stakeholders 
              thought that these workers should also be included in medical 
              surveillance programs because they are exposed as well and the 
              disease latency is short.

            4.6     Which employees should undergo a medical evaluation? Should 
            medical surveillance be tied to a particular action level?  Should 
            all employees who work in a particular process be part of the 
            medical surveillance program?  What criteria should be used to 
            identify effects of concern? Stakeholders provided the following 
            comments and suggestions on possible triggers for placing an 
            employee in a medical surveillance program:

              Many stakeholders agreed that medical surveillance should not be 
              tied to a specific action level but rather to job categories, 
              tasks, potentials for exposure, and disease progression. The 
              frequency of testing should be based on exposure potential and not 
              length of time exposed.

              Many stakeholders also thought that the rapid progression and 
              short latency of the disease should be taken into consideration 
              when determining the need for medical surveillance.

              One stakeholder cautioned against using time-weighted averages 
              (TWAs) as a trigger for joining a medical surveillance program, 
              citing short, high exposures to flavorings containing diacetyl 
              that are suspected of causing illness.

              In California, all employees who work in a particular job process 
              are being placed in the medical surveillance program.  Potential 
              for exposure determines placement in the medical screening 
program.

              Some stakeholders pointed to the need for developing a case 
              definition, while others cautioned against using a specific case 
              definition due to the wide range of disease manifestations.

              One stakeholder noted that Cal/OSHA is developing guidance on 
              medical surveillance for flavoring-related lung disease to be used 
              by physicians.

              In using a case definition, a few stakeholders thought that 
              certain red flags could trigger placement in a medical 
              surveillance program.  These red flags include (1) severe airway 
              obstruction (most non-smokers do not get obstructive lung 
              disease), (2) a greater than 10 percent decline in lung function 
              over a 6-month period, excluding individuals with genetic diseases 
              or asthma, and (3) evidence of fixed airway obstruction, 
              especially if flavoring exposure is certain.  The type of work and 
              past or present potential for exposure (e.g., a worker who 
              previously worked in the production room who moved to the 
              warehouse would have had a past exposure) should also be 
              considered in the need for medical screening.  Some stakeholders 
              thought that all workers should be screened if the employer did 
              not have sound knowledge of the processes and locations of 
              potential exposure.

              Another stakeholder suggestion is to employ an epidemiologic 
              concentric circle model to identify the employees that should be 
              placed in the medical surveillance program.  Rather than a 
              blanket, all-employee approach, employers should target those with 
              greatest potential for exposure, but err on the side of caution.  
              Under this model, the most exposed employees would be provided 
              medical surveillance and other employees working in the same area 
              would also be candidates for surveillance. Aerosolization of 
              diacetyl should be considered in identifying the target 
population.

            4.7     Is a baseline followed by a 6-month screening frequency 
            appropriate?  How should challenges with respect to testing at 
            6-month intervals be handled for temporary or contract workers? 
              Several stakeholders agreed that due to the rapid decline and 
              short latency issues associated with bronchiolitis obliterans, 
              screening should be performed at 6-month intervals.  In the case 
              of a plant or job operation with a known case of disease, 
              stakeholders suggested that the screening frequency could be 
              increased to less than 6 months.  Stakeholders also noted that 
              asymptomatic individuals could also manifest decreased lung 
              function.

              Stakeholders acknowledged that temporary workers pose a special 
              challenge to the 6-month screening rule.  It was suggested that if 
              temporary workers cannot be screened they should not work in 
              processes with exposure potential.

              Another stakeholder suggestion was that the frequency of screening 
              would vary depending on the worker's exposure potential.  For 
              workers with greater exposures or exposure potential, screening 
              frequency should be more often than every 6 months.  For workers 
              with lowered exposure potential the screening frequency could be 
              less frequent than every 6 months.

              Cases of lung disease have occurred in workers of various ages, 
              including young workers, and stakeholders cautioned against using 
              age-based criteria for determining evaluation frequency.

            4.8     What types of tests should be included in the medical 
            screening protocol?  Should certain tests be required for all 
            workers and additional tests for certain workers?  Should a 
            risk-based approach to spirometry testing be used? 
              One stakeholder suggested that a screening protocol include a 
              physical exam, occupational history, and spirometry.  A more 
              complex test, like a CT scan, could be used for follow-up testing, 
              but not for screening.  The use of bronchodilators should also be 
              considered in spirometry testing.

              The Cal/DHS has already screened 800 people and collected data 
              that could be used in developing definitions and medical 
              protocols.  Stakeholders noted that using these data could greatly 
              reduce the number of years required to develop such information as 
              part of the OSHA process.

              Stakeholders emphasized the difficulty in limiting the testing 
              protocol to a single complement of tests.  The general consensus 
              was that as more information about the exposures and disease 
              becomes available over time, the testing protocol may have to be 
              adjusted.  A very highly defined medical screening protocol may 
              not be valid in another 10 years.

              Stakeholders noted that strong education and training components 
              to medical testing exist. Considering language issues and ensuring 
              that employees understand the importance of their spirometry 
              testing is critical.  Employers should also understand the 
              importance of removing employees from exposures and ordering 
              additional testing.

            4.9     What qualified personnel (e.g., a clinician) should an 
            employer have on hand to help in the screening process? 
              Many stakeholders felt most occupational health clinicians should 
              know what key parameters to monitor and can rely on guidance 
              available from medical sources.  Following-up with employers to 
              ensure that they understand the surveillance and screening 
              processes is also important.

              Many stakeholders emphasized the need for spirometry to be 
              conducted by well-trained technicians.  Test and results can vary 
              by employee effort and technician ability.

            4.10     Are uniform questionnaires and spirometry testing important 
            to ascertain quality of the screening program? 
              Many stakeholders agreed that the spirometry quality is very 
              important and spirometry testing is typically fraught with quality 
              problems. One stakeholder suggestion was to stipulate criteria for 
              spirometry testing in the standard, including the need to follow 
              American Thoracic Society (ATS) criteria. Stakeholders also 
              suggested that technicians receive NIOSH spirometry training, and 
              that employers be required to periodically review the quality of 
              the technician's testing.  Saving a copy of the spirometry 
              tracing, not just the numerical results, is also important.  One 
              stakeholder recommended it would be more effective for OSHA to 
              suggest technicians receive formal spirometry training but not 
              mandate training in order to achieve greater compliance.  
              Conservative criteria could be used for screening purposes and 
              borderline findings could be followed up with additional 
              evaluation, suggested stakeholders.

              A few stakeholders urged OSHA to use validated occupational and 
              medical history questionnaires that exist and are in use, instead 
              of developing a new questionnaire.  OSHA can provide sample 
              questions but specific questions regarding work history will vary 
              by industry.

              Other stakeholder concerns raised during the discussion included 
              whether or not the standard should address spirometry equipment 
              quality.  The majority of equipment comes with American Thoracic 
              Society (ATS) standard software.  If the ATS software is routinely 
              updated and the spirometry technician prints out the tracing and 
              result, equipment quality need not be an issue.

            4.11     What actions should be taken if a worker has significant 
            findings? 
              Stakeholders suggested looking at other regulatory models, such as 
              the lead or noise standard, to determine the types of follow-up 
              actions that may be appropriate following identification of 
              significant medical findings.  The type of follow-up action should 
              depend on the medical finding.  For example, the workers may need 
              to be moved to another task to reduce exposure.

            4.12     What should be used for referral criteria? 
              Many stakeholders emphasized the lack of a case definition.  
              Particular concerns include the large variability in, and limited 
              knowledge currently available on the range of disease 
              manifestations.  For example, it is unclear whether health effects 
              due to chronic low level exposures differ from the effects of 
              intermittent peaks of high level exposure.

              A few stakeholders noted that relating follow-up actions to 
              exposure and clinical findings is important.  One stakeholder 
              suggestion is that the combination of a 10 percent decrease in 
              lung function, fixed airway obstruction, and an exposure pattern 
              that raises a red flag would lead to additional actions.

            4.13     OSHA requested that stakeholders submit any available 
            written medical guidelines to OSHA. 
              One stakeholder agreed to provide written guidelines to OSHA.  
              These include guidelines published in the Journal of Occupational 
              and Environmental Medicine (JOEM) and the ATS criteria on 
              acceptability and reproducibility of spirometry.

              The medical screening guidance that is being developed as part of 
              the evaluation of hundreds of workers in California will also be 
              shared with OSHA when ready.

            C.     Exposure Assessment 

            OSHA solicited information on the availability of exposure data, any 
            issues in sampling and analytical methodologies, and possible 
            exposure assessment strategies.

            4.14     What are the main methods available for use in exposure 
            assessment?  Should OSHA and NIOSH cooperate on sampling methods?  
            How can OSHA and NIOSH avoid duplication of efforts?  How are 
            humidity effect issues in the NIOSH method being addressed?

            Stakeholders and OSHA noted three sampling and analytical methods 
            available for diacetyl:

              The NIOSH method (published in 2004), which uses a carbon 
              molecular sieve sorbent tube (150/75 milligrams (mg) sorbent bed 
              size), does not have breakthrough issues, allows a single tube to 
              be used to sample throughout a whole shift, and offers a 
              relatively low limit of detection.

              Specific comments and concerns noted with respect to the NIOSH 
              method include:

                The method collection efficiency has been found to be influenced 
                by humidity. Currently, the method is being evaluated in 
                laboratory, field, and chamber studies to characterize the 
                nature and magnitude of diacetyl loss that occurs in humid 
                environments.  Additional information is available on the NIOSH 
                website http://www.cdc.gov/niosh/topics/flavorings/.  NIOSH no 
                longer considers this the preferred method for diacetyl sampling 
                until the humidity issues have been resolved.  The issue of 
                humidity was not previously noticed because humidity effects 
                typically cause breakthrough rather than compound loss on the 
                collection media. 

                The chamber evaluation studies on the NIOSH method will confirm 
                the degree to which humidity affects the results and may lead to 
                a correction factor (if necessary).  This will be applied to 
                older sampling data that were collected using this method.  
                NIOSH noted that most sampling data collected at popcorn plants 
                were collected during low relative humidity periods.  Thus, the 
                correction factor may be minimal or not required.

                One stakeholder noted that relative humidity may also be an 
                issue for dry encapsulated wetted flavorings, which release 
                diacetyl only when moist.

                The OSHA method (PV 2118) uses two silica gel sorbent tubes in 
                series. Each tube is of the150/75 mg sorbent bed size.  A 
                sampling air flow rate of 0.05 liters per minute and maximum 
                sample volume of 3 liters of air is recommended for this method. 
                 Using this protocol, sorbent tubes must be changed every hour 
                and 16 tubes are required to sample an 8-hour work shift.  The 
                OSHA method is not affected by humidity (designed for use at 80 
                percent relative humidity) and is relatively stable under 
                standard sample storage conditions.

              Specific comments and concerns noted with respect to the OSHA 
              method include:

                The OSHA method is currently a partially validated method with a 
                limit of quantification in the range of 0.3 ppm.  The OSHA 
                method has a higher detection limit than the NIOSH method, in 
                part because of the smaller sample air volume allowed by the 
                OSHA method.  The method is in the process of being fully 
                validated and OSHA anticipates in the eventual fully validated 
                method there might be some improvement in both the limit of 
                detection and the maximum air volume permitted for the fully 
                validated method.

                A modification to the OSHA method involves substituting silica 
                gel tubes of a larger size (400/200 mg sorbent bed), which 
                allows a longer sampling time and larger sample air volume.  
                NIOSH is using this modified method currently.

              Specific comments and concerns noted with respect to the OSHA 
              Modified method include:

                A few stakeholders noted one potential problem with the larger 
                sorbent tubes used in the modified OSHA method.  In some cases, 
                the motion of a vigorously active flavor worker can cause this 
                longer sampling train to accidentally disconnect.  OSHA 
                representatives noted that the tubes can be connected in a 
                series using methods that minimize this problem.  A simpler 
                sample train is also being considered.

                NIOSH cautioned against having any media to remove moisture 
                upstream of the sample.

                Two different sampling systems may be required for volatile 
                liquid and particulate samples, regardless of whether the 
                current NIOSH or OSHA methods are used. 
            In general, stakeholders supported both agencies working together on 
            developing sampling methods and inquired if any results were 
            available from a side-by-side comparison of the OSHA and NIOSH 
            methods.  This information will be available once the NIOSH method 
            has been evaluated.  Stakeholders urged OSHA and NIOSH to provide 
            information on method detection limits and noted that a lot of 
            task-based sampling is conducted in the field.

            4.15     What are other methodologies to measure episodic exposures? 

              One stakeholder suggested that neither the NIOSH nor the OSHA 
              methods were effective for episodic exposures.  They suggested 
              that the EPA TEO 17 method, based on thermal desorption, had a 
              lower detection limit than the OSHA method, and was a better 
              alternative.

            4.16     What real-time instruments can be used for monitoring?

            Stakeholders provided the following suggestions and concerns related 
            to real-time instruments for monitoring:

              OSHA identified photo-ionization detectors (PIDs) that retail for 
              $20,000 and use electron capture and gas chromatography.  These 
              instruments require an experienced operator.  Lower cost PIDs can 
              be used for screening purposes.

              The PID may be used to conduct onsite measurements.  Stakeholders 
              noted that flavor manufacturing typically contains approximately 
              ten batch operations, composed of 15 or more constituents.  Of 
              these, there are generally four to five compounds that are more 
              volatile and present at higher quantities than diacetyl or 
              acetoin.  Because of the complex mixtures, limitations to using 
              PIDs in the field may exist.

              In response to a stakeholder question about real-time instrument 
              function in a sampling environment that contains complex mixtures 
              like diacetyl-containing flavorings, OSHA representatives noted 
              that the potential for interference exists.  An air sample 
              collected on a sorbent tube may need to be sent to the laboratory 
              for additional testing.  Although OSHA prefers the specificity 
              offered by gas chromatography, real-time instruments are good 
              screening tools.

              A few stakeholders noted that the National Jewish Medical Center 
              and NIOSH are also using Fourier Transfer Infra Red Detection 
              (FTIR) in the popcorn and flavoring industries.  However, OSHA 
              does not have experience with this method currently.  This 
              computer-based, direct reading monitoring method works by relying 
              on the selectivity of infrared radiation detection to look at a 
              molecule.  This method does have potential for interference from 
              other compounds or bands in the spectrum and needs to be used 
              carefully.

              One stakeholder thought that more cost-effective screening tools 
              are available in place of FTIR.

              It was stated that a private firm is in the process of developing 
              an instrument to sample diacetyl and plans to release the 
              instrument in November 2007.

            4.17     What should be the frequency of sampling?  How can OSHA 
            describe a task-based sampling strategy in a regulation? 
              Some stakeholders noted that, in the flavoring industry, sampling 
              ideally occurs when a flavoring that contains diacetyl is being 
              produced.  A flavor of interest may only be produced once per 
              month.  Hence monitoring requires a great deal of coordination to 
              accommodate this high degree of variability.

              In contrast, in food manufacturing where the same product may be 
              produced every day, it was suggested that exposure levels can be 
              fairly constant from day to day for a given task and product type. 
               Monitoring would need to be repeated only with a process change.

              Monitoring should be left to the employer with guidance from OSHA 
              and NIOSH.

              One stakeholder noted the need to know the levels of concern, such 
              as the permissible exposure limit (PEL), in order to make 
              effective use of air monitoring.

              Another stakeholder noted that task-based sampling by NIOSH, the 
              National Jewish Medical Center, and Cal/OSHA shows that higher 
              exposures peaks occur during certain short-term operations.  
              Conversely, a longer full-shift sample reflects the average 
              exposure over the period sampled.  The longer sample period is 
              also valuable for comparing sampling methods.

              Stakeholders noted the need to think about how best to describe 
              task-based sampling strategies in regulatory language.

            4.18     What is the best way to keep stakeholders involved in the 
            exposure assessment process? 
              OSHA plans to post new methods at the web site www.osha.gov.

              A few stakeholders requested that OSHA and NIOSH describe the 
              relative advantages and disadvantages of each method for use in 
              the field.

              Some stakeholders also requested that OSHA establish a docket 
              where information relating to the diacetyl rulemaking process can 
              be received from the public and consolidated in a transparent way.

            D.     Control Methods

            OSHA sought information on possible substitutes for diacetyl in 
            diacetyl-containing products, process isolation techniques, use of 
            powders versus liquids, work practice controls, and respiratory 
            protection issues.

            4.19 Do substitutions eliminate the problem of diacetyl? 
              A few stakeholders noted that diacetyl is the single substance 
              most responsible for butter flavor.  Substitutes for diacetyl 
              (e.g., diacetyl trimers) exist, but information is lacking about 
              these substitutes and their safety.

              A lot of work is being conducted to find a substitute for 
              diacetyl.  Replacement compounds are expected to have a similar 
              structure in order to mimic the flavor perception.

            4.20     What criteria might OSHA use to guide companies on 
            substitutions? 

            Stakeholders provided the following comments and recommendations on 
            topics to address regarding substitutions:

              Substitute flavoring components are also chemicals and should be 
              carefully evaluated.  However, in the absence of concrete 
              information on the identity, health effects, or analytical methods 
              for substitute chemicals, OSHA may not be able to advise users on 
              how best to address them individually.  General exposure controls 
              and medical surveillance recommendations for flavorings as a 
              substance class could be more beneficial.

              One stakeholder noted that very few food flavoring chemicals are 
              tested for inhalation hazard.

              Limited information on MSDSs, due to the proprietary trade secret 
              nature of substitutions, will continue to be an issue.

              A few stakeholders noted that limited information exists on the 
              use of diacetyl in food manufacturing.  Substitutes will have 
              similar issues.  A standard on food flavorings containing diacetyl 
              may help alleviate some of this concern.

            4.21     What control mechanisms are used to reduce diacetyl 
            exposure?

            Stakeholders provided the following comments on and concerns with 
            controls used to protect employees from diacetyl exposure:

              Standard exhaust ventilation designs are the basis for engineering 
              controls in the blending operations of flavoring powder 
              manufacture.  However this type of control still requires 
              refinement, such as determining the level to which the air flow 
              rate (Q) should be set.

              PPE also continues to be a standard control in the popcorn and 
              flavoring industries.

              Examples were provided of other control methods, such as using 
              cold water to clean vessels and minimize volatilization, safe 
              handling methods, and safe pouring techniques. In general, common 
              sense solutions greatly reduce exposure.

              Trends are less well defined among the controls used in the food 
              manufacturing industry, which is diverse.

              The type of control methods that appear to be effective for 
              managing exposure to diacetyl and flavorings containing diacetyl 
              need not be sophisticated, but employee education, awareness, and 
              training are critical to their effective implementation.

              Flavoring manufacturing facilities vary in terms of existing 
              controls. Some facilities are new and have controls in place, 
              while other facilities are much older and may not have fully 
              installed controls.  Only about 100 to150 facilities exist 
              nationwide.

              Small companies are looking for expert guidance in using standard 
              controls efficiently.

              The effectiveness of exposure controls for flavor handling is 
              still being determined.

            4.22     What types of respirators are used? Are there any concerns 
            associated with respirator use?

            Stakeholders provided the following comments and concerns related to 
            respirator use:

              Full-faced respirators have been used since 2000 and are often 
              configured as air supplying respirators.

              There is a need to develop engineering controls that would 
              eliminate reliance on respirators.  In the meantime, respirators 
              can protect workers, especially if the company's management is 
              serious about enforcing use.

              Employee training and willingness to properly use respirators are 
              essential.

              A full-face respirator can restrict essential verbal communication 
              between employees.

              Respirator programs need to be effectively managed, with special 
              attention to the area of employee medical clearance to wear a 
              respirator.

            4.23     Can companies provide information on the cost of 
            implementing control methods to OSHA? 
              A few stakeholders expressed a willingness to provide OSHA with 
              cost information.  Case studies can be assembled to demonstrate 
              costs of controls in the past 5 years.

              Two stakeholders pointed to the need for guidance on the exposure 
              level to which diacetyl should be controlled.  This level 
              influences the design of controls and the associated installation 
              and usage costs.  A stakeholder added that new ventilation systems 
              are being designed to achieve the lowest technically feasible 
              exposure levels and this strategy seems to be effective.

            4.24     Is there value in a standard without a Permissible Exposure 
            Limit (PEL), but which includes medical surveillance requirements 
            and engineering controls?  What are some advantages and 
            disadvantages of setting a PEL?  How would companies know they had 
            done enough without a PEL?

            Stakeholders provided the following comments and concerns related to 
            development of a PEL for diacetyl: 
              Stakeholders emphasized the need to develop a standard based on 
              the current knowledge in order to move forward expeditiously.

              It was generally agreed that a PEL based on a safe level of 
              exposure would require further research, but the need exists to 
              quickly develop a standard that relies on currently available 
              information.  An interim standard could be based on engineering 
              controls, while additional research for a PEL is completed.  It 
              was noted that some companies lacked the most basic controls, so 
              an interim standard in the absence of a PEL would have great 
              benefit.

              Other stakeholders suggested that, in addition to engineering 
              controls, the first step could include a standard focused also on 
              exposure assessment, medical surveillance, employee education, and 
              respiratory protection., all geared toward the microwave popcorn 
              and flavorings manufacturing industries.  OSHA's influence on 
              these industries would likely stimulate action in those areas by 
              other industries, thus benefiting a broader workforce.

              However, some stakeholders cautioned OSHA against taking a long 
              time (e.g., 5 years) to develop a standard for microwave popcorn 
              and flavor manufacturing and then more time (e.g., another 5 
              years) to develop a food manufacturing industry standard.  The 
              two-step process was proposed as a means to expedite the 
              rulemaking process and to protect employees.

              Some stakeholders expressed a strong preference for having a PEL 
              in the standard in order to provide target criteria for engineers 
              to work towards in implementing controls, like local exhaust 
              ventilation.  Without a PEL to guide what constitutes an 
              acceptable level, employer will need to continue enforcing use of 
              respirators.

              Some stakeholders cautioned against assuming that a PEL afforded 
              the best protection for employees.  If a PEL is based on the 
              lowest limit detectable, that may not necessarily protect against 
              health effects.

              It was noted that deriving a PEL for a complex mixture like 
              diacetyl-containing flavoring substances is a difficult task.

              Issues with monitoring methods could further complicate PEL 
              development.

              There should be a high priority effort to encourage the necessary 
              research that will allow determination of a credible PEL.

              Stakeholders noted that while a standard focused solely on 
              diacetyl would be useful, a performance standard could address 
              other chemicals.

              OSHA representatives noted that OSHA must show material impairment 
              of health and significant risk (1/1000 risk of fatality or serious 
              illness) to develop a health-based standard.  Without such a 
              rigorous approach, the standard runs the risk of being challenged 
              in court.

            4.25     Would a standard focused exclusively on diacetyl be 
            effective? 
              Some stakeholders thought that controlling for diacetyl would 
              probably also limit most potentially hazardous exposures to other 
              flavoring components, but this depends on the products 
              manufactured.

              It was suggested that total volatile organic chemicals (VOCs) 
              should be considered in addition to diacetyl.

              Some stakeholders expressed concern about targeting one compound 
              (diacetyl) out of the 2,000 potential compounds in the volatile 
              flavorings industry.

              Other stakeholders cautioned that a standard for just diacetyl 
              could miss other potentially hazardous chemical exposures from 
              flavor ingredients.  While one stakeholder reported being unaware 
              of any flavorings-related lung disease in the absence of diacetyl, 
              another stakeholder suggested other flavoring components may have 
              a role in disease progression; hence, other chemicals besides 
              diacetyl should be considered in a standard.

              Members of the food manufacturing industry often find it difficult 
              to determine the presence and, if present, the amount of diacetyl 
              in the food flavorings they use.  A standard that encourages 
              control of the wider group of flavoring ingredients would be more 
              beneficial under these circumstances.

            5     Closing Remarks

            OSHA representatives thanked the stakeholders for their 
            participation.  To further assist OSHA in developing the standard, 
            OSHA representatives asked stakeholders to invite OSHA to visit 
            their facilities, if possible, as part of the information gathering 
            process. 

            *     *     *     *

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