Health Hazard Evaluation Report 2016-0012-3302 Page 1

Evaluation of exposures and respiratory 

health at a coffee roasting and packaging 

facility. 

Report No. 2016-0012-3302

January 2018

Marcia L. Stanton, BS

Stephen B. Martin, Jr., PhD, PE

Randall J. Nett, MD, MPH

U.S. Department of Health and Human Services

Centers for Disease Control and Prevention

National Institute for Occupational Safety and Health
Page 2 Health Hazard Evaluation Report 2016-0012-3302

Contents

Highlights...............................................i

Abbreviations .......................................v

Summary.............................................. 1

Introduction......................................... 2

Background.......................................... 2

Process Description............................. 6 

Methods ............................................... 9 

Results ................................................ 16

Discussion .......................................... 25

Conclusions........................................ 32

Recommendations............................. 32

Appendix A: Tables............................ 37

References.......................................... 50

Acknowledgements........................... 60

The employer is required to post a copy of this report for 30 days at or near the 

workplace(s) of affected employees. The employer must take steps to ensure 

that the posted report is not altered, defaced, or covered by other material.

The cover photo is a close-up image of sorbent tubes, which are used by the HHE

Program to measure airborne exposures. This photo is an artistic representation that may

not be related to this Health Hazard Evaluation.
Health Hazard Evaluation Report 2016-0012-3302 Page i

We evaluated respiratory 

health and airborne exposures 

to alpha-diketones (diacetyl, 

2,3-pentanedione, and 

2,3-hexanedione), other volatile 

organic compounds, carbon 

monoxide, and carbon dioxide 

during coffee roasting, grinding, 

and packaging. Diacetyl and 

2,3-pentanedione were detected 

in all full-shift personal breathing 

zone air samples, with a maximum 

diacetyl concentration of 25.6 parts 

per billion and 2,3-pentanedione 

concentration of 15.8 parts per 

billion. Seventy-eight percent of 

the full-shift personal samples 

exceeded the NIOSH recommended 

exposure limit for diacetyl of 5 

parts per billion. In addition, air 

sampling during short-term tasks 

identified several tasks (e.g., re-work 

of packaged coffee, moving roasted 

beans or ground coffee, grinding 

coffee) with higher exposures to 

alpha-diketones, including diacetyl, 

than other tasks. Nose, eye, sinus, 

and lower respiratory symptoms 

were among the most commonly 

reported symptoms. Wheezing 

and breathing trouble were the 

most common lower respiratory 

symptoms reported. Having current 

asthma was over 2.5 times higher 

than that expected compared with 

the U.S. population with the same 

distribution. No participants had 

abnormal spirometry results. We 

recommend limiting employee 

exposures to alpha-diketones using 

engineering and administrative 

controls. We also recommend 

training employees about 

workplace hazards and instituting a 

medical monitoring program.

Highlights of this Evaluation

The Health Hazard Evaluation Program of the National Institute for Occupational Safety 

and Health (NIOSH) received a request from the management of a coffee roasting and 

packaging facility regarding concerns about exposures to and health effects from diacetyl and 

2,3-pentanedione during coffee roasting, grinding, and packaging.

What We Did

● We visited the coffee processing facility 

on April 18–22, 2016 and April 25–29, 

2016.

● We collected full-shift (hours), task 

(minutes), and instantaneous (seconds) 

air samples to measure concentrations 

of the alpha-diketones diacetyl, 

2,3-pentanedione and 2,3-hexandione 

over multiple days.

● We collected roasted coffee beans 

(whole bean and ground) to measure 

their emission potential for diacetyl, 

2,3-pentanedione, and 2,3-hexanedione. 

● We measured real-time air levels of 

carbon monoxide and carbon dioxide. 

● We assessed the facility’s ventilation 

system.

● We administered a health questionnaire 

to employees and performed breathing 

tests.

What We Found

● Diacetyl concentrations were above the 

NIOSH recommended exposure limit of 

5 parts per billion in 78% of the full-shift 

personal samples. 

● 2,3-Pentanedione concentrations were 

above the NIOSH recommended 

exposure limit of 9.3 parts per billion in 

8% of the full shift personal samples.

● Employees in packaging had the highest 

average personal exposure to diacetyl of 
Page ii Health Hazard Evaluation Report 2016-0012-3302

13.2 parts per billion, with a maximum concentration of 25.6 parts per billion.

● The highest full-shift area samples were collected in grinding (diacetyl of 68.9 parts per 

billion and 2,3-pentanedione of 31.4 parts per billion). The roasting area had the second 

highest levels of diacetyl (37.8 parts per billion) and 2,3-pentanedione (23.0 parts per 

billion).

● Levels of diacetyl and 2,3-pentanedione in the air during short-term sampling were 

higher for tasks involving re-work of packaged coffee, moving roasted whole bean or 

ground coffee, and grinding coffee.

● There were opportunities for air from the production room to enter the office areas.

● Nose and eye symptoms were the most commonly reported symptoms. 

● Wheezing and breathing trouble were the most commonly reported lower respiratory 

symptoms; nearly two times as many employees reported wheezing as expected. 

● Approximately 2.5 times as many employees reported having current asthma as 

expected.

● None of the 75 participants tested had abnormal spirometry results.

● Six of 78 participants had elevated exhaled nitric oxide, a marker of allergic airways 

inflammation.

What the Employer Can Do

● Ensure employees understand potential hazards (e.g., diacetyl, 2,3-pentanedione, 

carbon monoxide, carbon dioxide, green and roasted coffee dust) in the workplace and 

how to protect themselves.

● Limit the amount of time non-production employees spend in the production area.

● Keep all doors between the production and non-production areas closed at all times.

● Work with a ventilation engineer to ensure the production area is maintained under 

negative pressure compared with non-production spaces.

● Isolate or relocate the main grinder.

● Install local exhaust ventilation at the point sources with the highest concentrations of 

alpha-diketones. 

● Conduct follow-up air sampling to verify the modifications have been effective in 

reducing exposures to below the recommended exposure limits. If modifications have 

not been effective, continue to work with a ventilation engineer to improve local 

exhaust and general ventilation to reduce exposures below recommended exposure 

limits. Also, until exposures are controlled, provide respiratory protection to be used 

during tasks with elevated exposures.

● Make N95 disposable filtering facepiece respirators available for voluntary use for 

protection against dust exposure such as when emptying burlap bags of green beans 

into the storage silos feed hopper, cleaning the exhaust system of chaff, emptying the 
Health Hazard Evaluation Report 2016-0012-3302 Page iii

chaff containers, or cleaning the green bean storage area. 

● Encourage employees to report new or ongoing respiratory symptoms to their personal 

healthcare providers and to a designated individual at the workplace.

● Institute a medical monitoring program for employees who work in the production area 

and in quality control.

What Employees Can Do

● Once local exhaust ventilation is installed, use it as instructed by your employer.

● As much as possible, avoid placing your head directly near sources of roasted or 

ground coffee beans, such as supersacks.

● Some employees might wish to use N95 disposable filtering facepiece respirators for 

some tasks, such as when emptying burlap bags of green beans into the storage silos 

feed hopper, cleaning the chaff out of the roaster exhaust system, emptying the chaff 

containers, or cleaning the green bean storage area.

● Participate in any personal air sampling offered by your employer.

● Report new or ongoing respiratory symptoms to your personal healthcare provider and 

a designated individual at your workplace.

● Participate in your employer’s medical monitoring program as instructed by your 

employer.
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Health Hazard Evaluation Report 2016-0012-3302 Page v

Abbreviations

μg Microgram

°F degrees Fahrenheit

ACGIH® American Conference of Governmental Industrial Hygienists

AX Area of reactance

CFR Code of Federal Regulations

CI Confidence interval

CO Carbon monoxide

CO2 Carbon dioxide

COHb Carboxyhemoglobin

COPD Chronic obstructive pulmonary disease

DR5-R20 The difference between resistance at 5 and 20 Hertz

FEV1 1-second forced expiratory volume

Fres Resonant frequency

FVC Forced vital capacity

Hz Hertz

kg/m2 Kilogram per square meter

kPa/(L/s) Kilopascals per liter per second

IDLH Immediately dangerous to life or health

LOD Limit of detection

LOQ Limit of quantitation

mL Milliliter

mL/min Milliliter per minute

NHANES National Health and Nutrition Examination Survey

NIOSH National Institute for Occupational Safety and Health

OEL Occupational exposure limit

OSHA Occupational Safety and Health Administration

PEL Permissible exposure limit

ppb Parts per billion

ppm Parts per million

R5 Resistance at 5 Hertz

R20 Resistance at 20 Hertz

REL Recommended exposure limit

RH Relative humidity

SMR Standardized morbidity ratios 

STEL Short-term exposure limit

TLV® Threshold limit value
Page vi Health Hazard Evaluation Report 2016-0012-3302

TVOC Total volatile organic compound

TWA Time-weighted average

US United States

VOC Volatile organic compound

X5 Reactance at 5 Hertz
Health Hazard Evaluation Report 2016-0012-3302 Page 1

Summary

In October 2015, the National Institute for Occupational Safety and Health’s Health Hazard 

Evaluation Program received a request from the management of a coffee roasting and 

packaging facility with 94 employees. The request stated concerns about exposures to and 

health effects from diacetyl and 2,3-pentanedione during coffee roasting, grinding, and 

packaging. In April 2016, we conducted a ventilation assessment of the production and 

office areas, industrial hygiene survey, and medical survey at the facility. The industrial 

hygiene survey consisted of collecting personal breathing zone and area air samples for 

alpha-diketones (i.e., diacetyl, 2,3-pentanedione, and 2,3-hexanedione). We used continuous 

monitoring instruments to measure total volatile organic compounds, carbon monoxide, 

carbon dioxide, temperature, and relative humidity in specific areas and during tasks. We 

also measured levels of carbon monoxide in employees’ exhaled breath. The medical survey 

consisted of a health questionnaire and breathing tests.

Sixty-nine of the 88 full-shift personal samples collected exceeded the NIOSH recommended 

exposure limit for diacetyl of 5 parts per billion, with a maximum concentration of 25.6 

parts per billion. We identified jobs where some work tasks resulted in relatively higher air 

concentrations of diacetyl than other tasks. Specifically, rework of packaged coffee, moving 

roasted beans or ground coffee, grinding coffee beans, and packaging coffee were associated 

with higher diacetyl levels. 

Overall, the most commonly reported symptoms were nose and eye symptoms. Some 

production employees reported their nose and sinus symptoms were caused or aggravated by 

green coffee dust or chaff, roasted coffee dust, or ground coffee dust. Wheezing or whistling 

in the chest was the most commonly reported lower respiratory symptom, and was nearly 

two times higher than that expected compared with the U.S. population of the same age, race/

ethnicity, sex, and cigarette smoking distribution. No participants had abnormal spirometry 

tests. We recommend installing local exhaust ventilation at the point sources with the highest 

concentrations of alpha-diketones. In addition to local exhaust ventilation, we recommend 

isolating or re-locating the main grinder. We also recommend a medical monitoring program 

to identify any employees who might be developing work-related lung disease (e.g., asthma, 

obliterative bronchiolitis) and to help management prioritize interventions to prevent 

occupational lung disease.

 
Page 2 Health Hazard Evaluation Report 2016-0012-3302

Introduction

In October 2015, the National Institute for Occupational Safety and Health (NIOSH) received 

a management request for a health hazard evaluation at a coffee roasting and packaging 

facility regarding potential worker exposure to diacetyl and 2,3-pentanedione during coffee 

processing. In April 2016, we conducted an industrial hygiene survey, ventilation assessment, 

and medical survey. We collected area and personal breathing zone air samples for volatile 

organic compounds (VOCs), including diacetyl, 2,3-pentanedione, and 2,3-hexanedione. We 

also monitored carbon monoxide (CO), carbon dioxide (CO2), and total VOCs. 

Background

Diacetyl and 2,3-Pentanedione 

Diacetyl (2,3-butanedione) and 2,3-pentanedione (acetyl propionyl) are VOCs known as 

alpha-diketones that are added as ingredients in food flavorings used in some food products 

such as microwave popcorn, bakery mixes, and flavored coffee [Day et al. 2011; Kanwal et 

al. 2006; Bailey et al. 2015]. Diacetyl, 2,3-pentanedione, other VOCs, and gases such as CO 

and CO2 are naturally produced and released during the coffee roasting process [Duling et al. 

2016; Raffel and Thompson 2013; Daglia et al. 2007; Nishimura et al. 2003; Newton 2002]. 

Grinding roasted coffee beans produces a greater surface area for off-gassing (sometimes 

called degassing) of these compounds [Akiyama et al. 2003]. Often, coffee roasting facilities 

package newly roasted coffee in permeable bags or in bags fitted with one-way valves to 

allow the coffee to off-gas after it is packaged. Sometimes, newly roasted coffee is placed in 

bins or containers and allowed to off-gas before packaging. 

NIOSH has recommended exposure limits (RELs) for diacetyl and 2,3-pentanedione in 

workplace air (Table 1) [NIOSH 2016]. The NIOSH objective in establishing RELs for 

diacetyl and 2,3-pentanedione was to reduce the risk of respiratory impairment (decreased 

lung function) and the severe irreversible lung disease obliterative bronchiolitis associated 

with occupational exposure to these chemicals. The NIOSH RELs are intended to protect 

workers exposed to diacetyl or 2,3-pentanedione for a 45-year working lifetime. The REL for 

diacetyl is based on a quantitative risk assessment which necessarily contains assumptions 

and some uncertainty. Analytical limitations current at the time were taken into consideration 

in setting the REL for 2,3-pentanedione. The RELs should be used as a guideline to indicate 

when steps should be taken to reduce exposures in the workplace.

These exposure limits and the accompanying recommendations for control of exposures 

were derived from a risk assessment of flavoring-exposed workers. At an exposure equal 

to the diacetyl REL, the risk of adverse health effects is low. NIOSH estimated that less 

than 1 in 1,000 workers exposed to diacetyl levels of 5 parts per billion (ppb) as a timeweighted average (TWA) for 8 hours a day, 40 hours a week for a 45-year working lifetime 

would develop reduced lung function (defined as forced expiratory volume in one second 

[FEV1] below the 5th percentile) as a result of that exposure. NIOSH predicted that around 

1 in 10,000 workers exposed to diacetyl at 5 ppb for a 45-year working lifetime would 
Health Hazard Evaluation Report 2016-0012-3302 Page 3

develop more severe lung function reduction (FEV1 below 60% predicted, defined as at 

least moderately severe by the American Thoracic Society [Pellegrino et al. 2005]). Workers 

exposed for less time would be at lower risk for adverse lung effects.

2,3-Hexanedione

2,3-Hexanedione is also an alpha-diketone that is sometimes used as a substitute for diacetyl 

and is produced naturally during coffee roasting. In a study using animals, there was some 

evidence that 2,3-hexanedione might also damage the lungs, but it appeared to be less 

toxic than diacetyl and 2,3-pentanedione [Morgan et al. 2016]. There are no established 

occupational exposure limits for 2,3-hexanedione.

Carbon Monoxide and Carbon Dioxide

CO and CO2 are gases produced by combustion. They are also produced as a result of 

reactions that take place during coffee roasting. These gases are released during and after 

roasting and grinding by a process called off-gassing [Anderson et al. 2003]. High exposures 

to CO and CO2 can cause headache, dizziness, fatigue, nausea, altered mentation, rapid 

breathing, impaired consciousness, coma, and death [Newton 2002; Nishimura et al. 2003; 

Langford 2005; CDC 2013; Raffel and Thompson 2013; Rose et al. 2017]. Occupational 

exposure limits for CO and CO2 are listed in Table 1.

Exposure Limits

We use mandatory (legally enforceable) and recommended occupational exposure limits 

(OELs) when evaluating workplace hazards. OELs have been developed by federal agencies 

and safety and health organizations to prevent adverse health effects from workplace 

exposures.

Occupational Safety and Health Administration (OSHA)

The U.S. Department of Labor’s OSHA permissible exposure limits (PELs) are legal limits 

enforceable in workplaces covered under the Occupational Safety and Health Act. OSHA 

PELs represent the legal maximum for a TWA exposure to a physical or chemical agent 

over a work shift [OSHA 2017]. OSHA short term exposure limits (STELs) are the legal 

maximum average exposure for a 15-minute time period. Some chemicals also have an 

OSHA ceiling value that represent levels that must not be exceeded at any time. Currently, 

there are no PELs for diacetyl, 2,3-pentanedione or 2,3-hexanedione. For substances for 

which an OSHA PEL has not been issued, violation of the OSHA General Duty Clause 

can be considered using available occupational exposure references and recommendations 

[OSHA 1993; OSHA 2003], such as the American Conference of Governmental Industrial 

Hygienists (ACGIH) Threshold Limit Values (TLVs®) and NIOSH RELs.

American Conference of Governmental Industrial Hygienist (ACGIH®) 

ACGIH is a professional, not-for-profit scientific association that reviews existing published, 

peer-reviewed scientific literature and publishes recommendations for levels of substances 

in air based on an 8-hour workday and 40-hour workweek. These recommendations are 

called TLVs [ACGIH 2017a]. ACGIH TLVs are not standards; they are health-based 

guidelines derived from scientific and toxicological information. ACGIH provides TLV-TWA 
Page 4 Health Hazard Evaluation Report 2016-0012-3302

guidelines that are levels that should not be exceeded during any 8-hour workday of a 40-

hour workweek. ACGIH also provides TLV-STEL guidelines which are 15-minute exposure 

levels that should not be exceeded during a workday. Exposures above the TLV-TWA but less 

than the TLV-STEL should be (1) less than 15 minutes, (2) occur no more than four times a 

day, and (3) be at least 60 minutes between exposures [ACGIH 2017a]. Additionally, ACGIH 

provides TLV-Ceiling values which are levels that should not be exceeded at any time during 

a work shift. The ACGIH TLV-TWA for diacetyl is 10 ppb. The TLV-STEL for diacetyl is 20 

ppb. Currently, there is no TLV-TWA or TLV-STEL for 2,3-pentanedione. ACGIH has placed 

2,3-pentanedione on the 2017 list of Chemical Substances and Other Issues Under Study 

[ACGIH 2017b]. 

National Institute for Occupational Safety and Health (NIOSH)

NIOSH provides RELs as TWA concentrations that should not be exceeded over an 8 or 

10-hour work shift, during a 40-hour workweek [NIOSH 2010]. RELs are intended to 

be protective over a 45-year working lifetime. NIOSH also provides STELs which are 

15-minute TWA exposures that should not be exceeded at any time during a workday 

[NIOSH 2010]. Some chemicals have ceiling values which are concentrations that should 

not be exceeded at any time [NIOSH 2010]. For some chemicals, NIOSH has Immediately 

Dangerous to Life or Health (IDLH) values. An IDLH value is a concentration of an air 

contaminant that can cause death or immediate or delayed permanent adverse health effects, 

or prevent escape from such an environment. Currently, NIOSH has RELs and STELs for 

diacetyl and 2,3-pentanedione. NIOSH does not have a REL or a STEL for 2,3-hexanedione. 

NIOSH does not have ceiling limits or IDLH values for diacetyl, 2,3-pentanedione, or 

2,3-hexanedione. 

For diacetyl and 2,3-pentanedione, the NIOSH RELs are 5.0 ppb and 9.3 ppb, respectively, 

as a TWA for up to an 8-hour workday during a 40-hour workweek (Table 1). The NIOSH 

STELs are 25 ppb for diacetyl and 31 ppb for 2,3-pentanedione [NIOSH 2016]. The NIOSH 

exposure standards do not differentiate between natural and synthetic chemical origin of 

diacetyl or 2,3-pentanedione. Although the NIOSH exposure limit for 2,3-pentanedione 

is above that of diacetyl, 2,3-pentanedione has been shown to be as hazardous as diacetyl 

[Hubbs et al. 2012; Morgan et al. 2012]. The hazard potential probably increases when these 

chemicals occur in combination with each other; having exposure to chemicals with the same 

functional alpha-diketone group and effect on the same system or organ (e.g., lungs) can 

result in additive effects [ACGIH 2017a]. The NIOSH REL is higher for 2,3-pentanedione 

than for diacetyl largely because analytic measures were not available in a validated OSHA 

method to detect 2,3-pentanedione at lower levels. In addition to the REL, NIOSH also 

recommends an action level for diacetyl of 2.6 ppb to be used with exposure monitoring in an 

effort to ensure employee exposures are routinely below the diacetyl REL. When exposures 

exceed the action level, employers should take corrective action (i.e., determine the source of 

exposure, identify methods for controlling exposure) to ensure that exposures are maintained 

below the NIOSH REL for diacetyl [NIOSH 2016].
Health Hazard Evaluation Report 2016-0012-3302 Page 5

Table 1. Personal exposure limits for compounds sampled for during the NIOSH survey, 

April 2016.

OSHA* ACGIH NIOSH

Compound PEL TLV STEL REL STEL IDLH

Diacetyl — 10 ppb 20 ppb 5.0 ppb† 25 ppb —

2,3-Pentanedione — — — 9.3 ppb† 31 ppb —

2,3-Hexanedione — — — — — —

Carbon dioxide§ 5,000 ppm 5,000 ppm 30,000 

ppm 5,000 ppm 30,000 ppm 40,000 ppm

Carbon 

monoxide§ 50 ppm 25 ppm — 35 ppm 200 ppm (ceiling limit)¶ 1,200 ppm

Note: OSHA=Occupational Safety and Health Administration; ACGIH=American Conference of 

Governmental Industrial Hygienist; NIOSH=National Institute for Occupational Safety and Health; 

PEL=permissible exposure limit; TLV=threshold limit value; STEL=short-term exposure limit; 

REL=recommended exposure limit; IDLH=immediately dangerous to life or health; ppb=parts per 

billion; ppm=parts per million; “—“=no exposure limit available. 

*There are no OSHA STELs for the compounds in the table.

†The NIOSH RELs for diacetyl and 2,3-pentanedione are time-weighted averages for up to 8-hour day, 

during a 40-hour workweek.

§OSHA and NIOSH limits are designed for occupational exposure measurements in manufacturing and 

other trades that have potential sources of carbon dioxide or carbon monoxide (e.g., welding, vehicle 

exhaust, diesel engine exhaust). Typical levels of carbon monoxide in offices are 0–5 ppm. In office 

settings, carbon dioxide generally should not be greater than 700 ppm above outdoor carbon dioxide 

levels; this typically corresponds to indoor concentrations below 1200 ppm. 

¶This is the NIOSH ceiling exposure limit for carbon monoxide. A ceiling concentration should not be 

exceeded at any time.

Obliterative Bronchiolitis

Obliterative bronchiolitis is a serious, often disabling, lung disease that involves scarring 

of the very small airways (i.e., bronchioles). Symptoms of this disease can include cough, 

shortness of breath on exertion, and/or wheeze, that do not typically improve away from 

work [NIOSH 2012]. Occupational obliterative bronchiolitis has been identified in flavoring 

manufacturing workers and microwave popcorn workers who worked with flavoring 

chemicals or butter flavorings [Kreiss 2013; Kim et al. 2010; Kanwal et al. 2006]. It has 

also been identified in employees at a coffee processing facility that produced unflavored 

and flavored coffee [CDC 2013]. A NIOSH health hazard evaluation at that facility found 

diacetyl and 2,3-pentanedione concentrations in the air that were concerning and identified 

three sources: 1) flavoring chemicals added to roasted coffee beans in the flavoring area; 2) 

grinding unflavored roasted coffee beans and packaging unflavored ground and whole bean 

roasted coffee in a distinct area of the facility, and 3) storing roasted coffee in hoppers, on 

a mezzanine above the grinding/packaging process, to off-gas [Duling et al. 2016]. At the 

time of the health hazard evaluation, workers had excess shortness of breath and obstruction 

on spirometry, both consistent with undiagnosed lung disease. Respiratory illness was 

associated with exposure and not limited to the flavoring areas [Bailey et al. 2015]. However, 

all workers who were diagnosed with obliterative bronchiolitis had worked in the flavoring 

area. To date, no cases of obliterative bronchiolitis have been reported in workers at coffee 
Page 6 Health Hazard Evaluation Report 2016-0012-3302

roasting and packaging facilities that produce only unflavored coffee.

Work-related Asthma

Work-related asthma refers to asthma brought on by (“occupational asthma”) or made worse 

by (“work-exacerbated asthma” or “work-aggravated asthma”) workplace exposures [Tarlo 

2016; Tarlo and Lemiere 2014; OSHA 2014; Henneberger et al. 2011]. It includes asthma 

due to sensitizers, which cause disease through immune (allergic) mechanisms, and asthma 

due to irritants, which cause disease through non-immune mechanisms. Symptoms of workrelated asthma include episodic shortness of breath, cough, wheeze, and chest tightness. The 

symptoms may begin early in a work shift, towards the end of a shift, or hours after a shift. 

They generally improve or remit during periods away from work, such as on weekends or 

holidays. 

Green and roasted coffee dust and castor beans (from cross-contamination of bags used to 

transport coffee) are known risk factors for occupational asthma [Figley and Rawling 1950; 

Karr et al. 1978; Zuskin et al. 1979, 1985; Thomas 1991]. Persons who become sensitized 

(develop an immune reaction) to coffee dust can subsequently react to relatively low 

concentrations in the air. Others can experience irritant-type symptoms from exposure to 

coffee dust [Oldenburg et al. 2009].

Previous Industrial Hygiene Sampling at This Coffee Processing Facility

On September 23, 2015, an industrial hygiene contractor collected area and TWA personal air 

samples in the roasting and grinding areas. Personal full-shift samples were collected from 

two employees who roasted coffee (roasters) and one employee who ground and packaged 

coffee. In addition to the TWA sampling, short-term (15 minute) personal samples were 

collected during specific tasks. According to the industrial hygiene report dated October 21, 

2015, all sample results were above the NIOSH REL of 5 ppb [NIOSH 2016] and the ACGIH 

TLV of 10 ppb [ACGIH 2016] for diacetyl. TWA exposures for the three personal samples 

ranged from 48 ppb–94 ppb. The NIOSH STEL is 25 ppb for diacetyl [NIOSH 2016] and the 

ACGIH TLV-STEL is 20 ppb [ACGIH 2016]. The STEL is a 15-minute TWA exposure that 

should not be exceeded at any time during a workday. Two short-term (15 minute) samples 

were collected during roasting and grinding activities. The STEL result collected on a roaster 

was 98 ppb and the grinder result was 46 ppb, both above the NIOSH and ACGIH STELs.

Based on these air sampling results, the coffee roasting and packaging company wanted to 

be proactive and more fully characterize concentrations of alpha-diketones in the air and 

assess the efficiency of the existing ventilation systems. In October 2015, the management 

submitted a health hazard evaluation request to NIOSH.

Process Description

The facility was approximately 70,000 square feet with 45,000 square feet dedicated to 

production activities. At the time of the NIOSH visit in April 2016, approximately 60 

employees were located at the main location. The production activities were performed by 
Health Hazard Evaluation Report 2016-0012-3302 Page 7

approximately 20 employees and supported by three quality control laboratory employees. 

Production activities occurred over two shifts in a 5-day workweek with most employees 

working 8-hour shifts. The remaining employees were involved in administrative tasks 

including accounts receivable, customer service, inventory control, graphic design, sales, 

community outreach, and farmer relations. In addition to the main location, an additional 30 

employees had relocated to an offsite facility in the spring of 2015. At this site, distribution 

activities for finished goods including coffee and chocolate products were performed 

by approximately 12 warehouse employees while the remaining employees performed 

administrative tasks in office settings.

Green coffee beans were received in burlap or jute bags from 13 countries. After arrival in 

the facility’s receiving area, pallets of bagged beans were stored by origin and lot in the green 

coffee bean storage area until needed in the roasting area. In preparation for roasting, burlap 

bags were cut open and green beans emptied into a feed hopper. From the feed hopper, the 

beans were conveyed into a shaker and magnetic separator where they underwent cleaning 

before being pneumatically transferred into one of eight storage silos; total silo capacity was 

approximately 32,000 pounds of beans. 

To prepare a batch for roasting, green coffee beans were pneumatically fed into a roaster 

feed hopper and automatically inducted into the roaster barrel on either one of two natural 

gas fired (convection) roasters. The Probat R-1000 roaster is capable of roasting 440 pounds 

of green beans while the Probat G-120 roaster can accommodate 230 pounds. Batches were 

automatically pulled from a single silo or more than one silo if a blend of beans was to be 

roasted. The beans were heated at a specific temperature and for a precise time to achieve the 

desired roast profile. Types of roasts offered included medium, Full City, Vienna, or French 

roasts. At the end of each roast cycle, the roasted beans were automatically water quenched 

inside the roaster barrel to initiate the cooling process before being automatically transferred 

into the enclosed cooling bin for mechanical mixing by an agitator to accelerate cooling. The 

enclosed cooling bin used an up-draft exhaust system that pushed air up from the bottom 

of the bin, over the roasted beans, and out the roof-top exhaust. Exhaust from each roasting 

barrel and cooling tray/bin flowed through a particulate cyclone and thermal oxidizer. Once 

the roasted beans were cooled, the roaster operator collected a sample for quality control 

checks. Quality control checks involved grinding a small amount of roasted beans and 

testing the roast color profile using a color analyzer. The beans were then transferred through 

a pneumatic destoner into either a rolling tote or supersack (large industrial sized bag). A 

roaster operator monitored the roasting equipment carefully throughout the roasting and 

cooling process. Containers with roasted beans were then moved to the off-gassing, blending, 

grinding, or packaging areas. 

Routine cleaning activities were employed at both roasters. Chaff from the destoner trays 

was emptied daily. The roaster operator used a shovel to clean out the chaff barrel from the 

roaster cyclone and transferred chaff from the barrel into large plastic bags that were donated 

to local farmers. For the R1000 roaster, a thermal clean-out was initiated every 80 hours. 

This 1.5-hour automated process involved running the roaster at high temperatures to remove 

buildup of organic material from the inside of the emission pipes. All emissions were routed 
Page 8 Health Hazard Evaluation Report 2016-0012-3302

through the thermal oxidizer as in normal roasting. For the G120 roaster, a manual cleaning 

process was initiated every 500 hours. This process involved removing emission piping from 

the machine and cleaning any organic buildup inside the emission pipes.

Unlined supersacks were staged in the off-gassing area for a period of 24 hours–48 hours. 

Roasted whole coffee beans were fed into hoppers and transferred through a conveyance 

blender to feed the 5 pound packaging line. In the grinding area, a production employee used 

a hoist to raise roasted whole bean supersacks to the top of the grinder hopper. The supersack 

was then manually untied, and the roasted beans were gravity-fed into the grinder. Typical 

batch sizes were approximately 400 pounds. The grinder could be adjusted for type of grind 

(coarse, medium, or fine). Ground coffee was collected in another supersack attached to the 

discharge chute. At times during grinding, the employee manually collected a sample of the 

ground coffee at the discharge chute. Once grinding was completed, a production employee 

moved the supersack to its applicable packaging line.

In addition to the large capacity production grinder, two small table-top grinders accessible 

to all employees were located just inside the production area. These grinders were used at 

various times throughout the day for personal use.

Roasted whole bean and ground coffee were packaged on one of four automated packaging 

lines. All packages were flushed with nitrogen before filling to ensure freshness. On the can 

line, whole bean and ground coffee were packaged in 14 ounce fully-recyclable cans. These 

cans featured a foil lid fitted with a one-way valve. This line was staffed by four production 

assistants and an employee to palletize finished product. Ground coffee was processed on the 

can line approximately twice a month. Whole bean coffee was packaged in 5 pound bags that 

were fitted with one-way valves and heat-sealed. Two 5 pound bags were packed into each 

cardboard box by a production assistant. Whole bean and ground coffee were packaged into 

both 10 ounce and 12 ounce bags fitted with one-way valves and heat-sealed. Once packaged, 

bags were packed into cardboard boxes. Ground coffee previously off-gassed for a minimum 

of 48 hours was packaged into 1.5, 2.25, 2.5, 7.0, or 8 ounce packages on the pillow pack 

line for use in commercial 12 cup or 1.5 gallon brewers. After filling, these packs were 

heat-sealed and packaged into cases. In addition to the automated packaging lines, a hand 

packaging station was used to package whole bean and ground coffee in smaller quantities 

via a weigh-fill machine.

Each packaging line was monitored by production assistants to assure quality of packaging. 

In the event of packaging defects, some re-work of product was required. Re-work involved 

manually cutting open defective packaging, emptying coffee into a plastic container, and 

then returning coffee to the supply hopper on the appropriate packaging line. After individual 

packages were filled, they were heat sealed, packaged and palletized, and moved via forklift 

to a staging area for transfer to the offsite warehouse.

There was a small maintenance area with one designated employee responsible for 

maintenance of production equipment.
Health Hazard Evaluation Report 2016-0012-3302 Page 9

The primary purpose of the quality control laboratory, located across from the loading 

docks and the staging area, was to ensure the quality of the coffee produced at the facility. 

Coffee quality was evaluated daily by a process called cupping, where quality control staff, 

purchasers, and production roasters smelled, tasted, and assigned scores to coffee brewed 

from samples of roasted beans. The roasted beans used for cupping came from three sources: 

coffee bean samples from farmers (pre-ship), purchased coffee beans shipped to the facility 

(arrival), and beans roasted at the facility (production). The quality control laboratory 

completed three to four cuppings per day. Cuppings were prepared by roasting coffee beans, 

grinding roasted beans, and brewing. The cupping process takes approximately one hour 

depending on the types of beans being evaluated (i.e., pre-ship, arrival, or production).

In addition to cupping, the quality control staff also graded green coffee beans, roasted coffee 

bean samples, conducted triangulations used to certify and grade tasters, analyzed brewed 

coffee, and tested packaging. All procedures in the quality control laboratory were performed 

in accordance with standards and protocols set by the Specialty Coffee Association of 

America.

Various cleaning techniques were used throughout production areas. Cleaning methods 

used for the production area and equipment included sweeping (dry and wet), wiping (dry 

and wet cloths), and using compressed air. Employees used brooms to routinely sweep the 

production floor and once a week used a floor scrubber. They used wet or dry wipes on table 

tops and equipment surfaces and compressed air to remove coffee bean dust from surfaces 

and equipment. 

Employees were not required to wear a company uniform or protective clothing. Upon 

entry into the production area employees were required to wear a hair net or hat. Hearing 

protection was recommended for the roasting and grinding areas. Some employees were 

observed using hearing protection. Voluntary use of N95 filtering facepiece respirators was 

reported. 

Methods

We visited the coffee processing facility in April 2016. We performed the industrial 

hygiene survey during April 18–22, 2016. On the first day, we held an opening meeting 

with management and employee representatives from all work areas to explain the health 

hazard evaluation process and to describe the sampling procedures. For part of the first 

day, we were joined by representatives from the Massachusetts Department of Public 

Health. During the remainder of the week, we performed a ventilation assessment in 

the production area, collected air samples, and collected bulk samples of roasted coffee. 

We also toured the warehouse location where finished product was stored before being 

shipped. At the conclusion of the industrial hygiene survey, we held a brief closing meeting 

with management and employee representatives. The medical survey was performed 

during April 25–29, 2016. We provided a letter detailing our evaluations and preliminary 

recommendations to management on May 10, 2016.
Page 10 Health Hazard Evaluation Report 2016-0012-3302

We had the following objectives for the health hazard evaluation:

1. Measure employees’ exposure to diacetyl, 2,3-pentanedione, and 2,3-hexanedione 

during coffee processing;

2. Identify process areas or work tasks associated with elevated levels of diacetyl, 

2,3-pentanedione, and 2,3-hexanedione;

3. Measure levels of CO and CO2 in areas of the facility;

4. Measure CO levels in employees’ exhaled breath;

5. Assess ventilation systems and their effect on exposure levels;

6. Determine if employees had mucous membrane, respiratory, or systemic symptoms, 

and the proportion of those symptoms that were work-related or aggravated by work;

7. Determine if employees had abnormal lung function tests; 

8. Compare employees’ prevalence of lower respiratory symptoms and healthcare 

provider-diagnosed asthma with expected levels based on general population values.

Industrial Hygiene Survey

Sampling Times for Alpha-Diketones 

We designed the sampling strategy to assess full-shift exposures and identify tasks and 

processes that were the greatest contributors to worker exposure to alpha-diketones. For 

diacetyl, 2,3-pentanedione, and 2,3-hexanedione, air samples were collected over seconds, 

minutes, and hours. Samples collected over hours can help determine average concentrations 

that can be compared with the NIOSH RELs for diacetyl and 2,3-pentanedione. These 

average concentrations might not tell us about short-term peak exposures that could be 

relevant to respiratory health, particularly when tasks are repeated multiple times per day. 

Therefore, during particular tasks, we collected air samples over several minutes. When the 

samples were equal to 15 minutes, we also conducted instantaneous sampling over seconds to 

help identify point sources of alpha-diketones

Employees who participated in air sampling were given the opportunity to request their 

individual air sampling results

Air Sampling and Analysis Using Occupational Safety and Health Administration (OSHA) 

Methods 1013/1016

We collected personal and area air samples for diacetyl, 2,3-pentanedione, and 

2,3-hexanedione on silica gel sorbent tubes. The samples were collected and analyzed 

according to the modified OSHA sampling and analytical Methods 1013/1016 [OSHA 2008; 

OSHA 2010; LeBouf and Simmons 2017]. In accordance with the two methods, two glass 

silica gel sorbent tubes were connected by a piece of tubing and inserted into a protective, 

light-blocking cover. The tubes were connected in series to a sampling pump pulling air 

through the tubes at a flow rate of 50 milliliters per minute (mL/min). The sampling setup 

was attached to an employee’s breathing zone or placed in an area basket in various places 
Health Hazard Evaluation Report 2016-0012-3302 Page 11

throughout the facility. For full-shift personal sampling, we collected two consecutive 3-hour 

samples and calculated the TWA concentration from the two samples, assuming the total 

6-hour monitoring results reflected a full work shift (8-hour) TWA exposure. Although this 

might introduce some error, it is a conservative approach more protective of employees than 

the alternative assumption of no exposure during the last two hours of the shift. We refer to 

these samples as “full-shift samples” throughout this report. Area samples on the first three 

days of sampling were collected using three consecutive 3-hour samples and on the fourth 

day of sampling two consecutive 3-hour samples were collected. We also collected shortterm, task-based samples during specific work tasks (e.g., roasting, grinding, packaging) 

with a sampling pump flow rate of 200 mL/min as detailed in OSHA Methods 1013 and 

1016 [OSHA 2008; 2010]. Sampling times were dependent on the duration of the task being 

performed. 

Analyses of the samples were performed in the NIOSH Respiratory Health Division’s 

Organics Laboratory. The samples were extracted for one hour in 95% ethanol:5% water 

containing 3-pentanone as an internal standard. Samples were analyzed using an Agilent 

7890/7001 gas chromatograph/mass spectrometer system operated in selected ion monitoring 

mode for increased sensitivity compared to the traditional flame ionization detector used in 

OSHA Methods 1013 and 1016 [LeBouf and Simmons 2017].

A limit of detection (LOD) is the lowest mass an instrument can detect above background 

and is a criteria used to determine whether to report a result from a sample. The limit of 

quantitation (LOQ) is the lowest mass that can be reported with precision; we have a greater 

confidence in the reported result if above the LOQ. The samples were analyzed using 

two instruments. The LODs were 0.005 micrograms per sample (μg/sample) for diacetyl, 

2,3-pentanedione, and 2,3-hexanedione on instrument A. For a typical full-shift air sample, 

these equate to 0.32 ppb for diacetyl, 2,3-pentanedione, and 2,3-hexanedione. The LODs for 

the instrument B were 0.005 μg/sample for diacetyl, 0.006 μg/sample for 2,3-pentanedione, 

and 0.01 μg/sample for 2,3-hexanedione. For a typical full-shift air sample, these equate 

to 0.32 ppb for diacetyl, 0.33 ppb for 2,3-pentanedione, and 0.48 for 2,3-hexanedione. The 

LODs for task samples vary because of differing air volumes collected while sampling 

specific tasks and are higher than typical LOD values for full-shift samples. When the 

values presented in the report are from samples below the LOD they are denoted by a “<” 

symbol. The LOQs for instrument A equate to 1.1 ppb for diacetyl, 2,3pentanedione, and 

2,3-hexanedione. The LOQs for instrument B equate to 1.05 ppb for diacetyl, 1.08 for 

2,3-pentanedione, and 1.59 for 2,3-hexanedione instrument B for a typical full-shift air 

sample.

Air Sampling and Analysis Using Evacuated Canisters

In addition to OSHA’s sampling methods for diacetyl and 2,3-pentanedione, NIOSH has 

also been using evacuated canisters [LeBouf et al. 2012] with flow controllers to collect air 

samples for diacetyl, 2,3-pentanedione, and 2,3-hexanedione in workplaces.

We collected instantaneous task-based and source air samples for VOCs including diacetyl, 

2,3-pentanedione, and 2,3-hexanedione using evacuated canisters. We also collected 
Page 12 Health Hazard Evaluation Report 2016-0012-3302

instantaneous air samples before and after the work shift to determine if air concentrations of 

alpha-diketones varied over a work shift. The evacuated canister sampling setup consisted of 

a 450-mL evacuated canister equipped with an instantaneous flow controller designed for a 

short sampling duration (less than 30 seconds). Instantaneous samples were taken by opening 

the evacuated canister to grab a sample of air. For task-based air samples, a NIOSH employee 

placed the inlet of the flow controller by the employee’s personal breathing zone as they 

performed their work task to replicate exposure. For source air samples, a NIOSH employee 

placed the inlet of the flow controller directly at the source of interest.

The canister air samples were analyzed using a pre-concentrator/gas chromatograph/

mass spectrometer system pursuant to a published method validation study [LeBouf 

et al. 2012], with the following modifications: the pre-concentrator was a Model 7200 

(Entech Instruments, Inc., Simi Valley, CA), and six additional compounds (diacetyl, 

2,3-pentanedione, and 2,3-hexanedione, acetaldehyde, acetonitrile, and styrene) were 

included. At present, this canister method is partially validated [LeBouf et al. 2012] and 

not considered the standard method. The LODs were 0.39 ppb for diacetyl, 0.54 ppb for 

2,3-pentanedione, and 0.96 ppb for 2,3-hexanedione. However, LODs are dependent on the 

pressure inside each canister after samples have been collected and they might be higher or 

lower than typical LOD values.

Bulk Sampling and Headspace Analysis

We used 50-mL sterile polypropylene centrifuge tubes to collect approximately 40-mL 

bulk samples of roasted coffees (whole bean and ground). For headspace analysis of alphadiketones, we transferred 1 gram of solid bulk material bulk material into a sealed 40-mL

amber volatile organic analysis vial and let it rest for 24 hours at room temperature (70°F) 

in the laboratory. Then 2 mL of headspace air was transferred to a 450-mL canister and 

pressurized to approximately 1.5 times atmospheric pressure. Using the canister analysis 

system, the concentrations were calculated in ppb of analytes in the headspace as an indicator 

of emission potential. 

Real-time Air Sampling

We used RAE Systems (San Jose, CA) ppbRAE 3000 (Model #PGM-7340) monitors to 

measure levels of total volatile organic compounds (TVOCs) in the air. The ppbRAE has a 

non-specific photoionization detector that responds to chemicals with ionization potentials 

below the energy of the lamp. This sampling was conducted to identify areas where coffee 

could be releasing VOCs. Areas with higher release of VOCs can be targets for sampling for 

alpha-diketones and for exposure controls. We also collected real-time measurements of CO2, 

CO, temperature, and relative humidity (RH) in various locations using TSI Incorporated 

(Shoreview, MN) VelociCalc Model 9555-X Multi-Function Ventilation Meters equipped 

with Model 982 IAQ probes.

Exhaled CO Measurements

We asked employees to perform a carboxyhemoglobin (COHb) test one or more times 

throughout their shift to measure CO levels in their exhaled breath. This test helps determine 

if employees are exposed to elevated levels of CO. Employees were asked to hold their 
Health Hazard Evaluation Report 2016-0012-3302 Page 13

breath for 15 seconds and then exhale through a mouthpiece into a CO monitor. The device 

then calculated an estimate of COHb in blood. We asked participants when they last smoked 

cigarettes or used tobacco products. Tobacco smoke from cigarettes, cigars, and pipe tobacco 

contains CO and can cause an increase in exhaled CO. Employees who participated in COHb 

testing were mailed their individual test results.

Ventilation Assessment

We completed visual and physical assessments of all ventilation components at the facility. 

Physical measurements were taken with a Model DISTO E7100i laser-tape measure (Leica 

Geosystems AG, Heerbrugg, Switzerland). Because of the height, configuration, and large 

airflow rate of the two makeup air units used to supply fresh air in the production area 

space, we did not have equipment that allowed for ventilation measurements. However, 

we collected information on existing ventilation equipment, including make, model, and 

specified performance levels. Differential pressure measurements between adjacent spaces 

were taken under various ventilation scenarios using an Energy Conservatory (Minneapolis, 

MN) DG-500 Pressure Gauge.

NIOSH Medical Survey

Participants 

We invited all current employees to participate in the medical survey at the workplace during 

April 25–29, 2016. Participation was voluntary; written informed consent was obtained 

from each participant before testing. An interpreter was used during the medical survey for 

non-English speaking employees. The survey included, in the order performed, a medical 

and work history questionnaire, quantification of exhaled nitric oxide, impulse oscillometry, 

spirometry, and if indicated the administration of a bronchodilator with repeat impulse 

oscillometry and spirometry. We mailed participants their individual reports explaining their 

breathing test results and recommended each participant provide the information to their 

personal physician. 

Questionnaire 

We used an interviewer-administered computerized questionnaire to ascertain symptoms 

and diagnoses, work history at this coffee roasting and packaging facility and other coffee 

or flavoring companies, and cigarette smoking history. Questions on respiratory health were 

derived from five standardized questionnaires, the European Community Respiratory Health 

Survey [Burney et al. 1994; ECRHS 2014], the American Thoracic Society adult respiratory 

questionnaire (ATS-DLD-78) [Ferris 1978], the International Union Against Tuberculosis 

and Lung Disease [Burney et al. 1987, 1989], and the Third National Health and Nutrition 

Examination Survey (NHANES III) [CDC 1996] and NHANES 2007–2012 questionnaires 

[CDC 2018]. Some of the questions appeared on more than one of the standardized 

questionnaires. We also supplemented our questionnaire with additional respiratory and 

systemic symptom questions. 

Spirometry 

The purpose of the spirometry test was to determine a person’s ability to move air out of their 

lungs. Test results were compared with expected normal values. The test included the three 
Page 14 Health Hazard Evaluation Report 2016-0012-3302

measurements or calculations: 1) forced vital capacity (FVC) (the total amount of air the 

participant can forcefully blow out after taking a deep breath), 2) 1-second forced expiratory 

volume (FEV1) (the amount of air that the participant can blow out in the first second of 

exhaling), and 4) the calculation of the ratio of FEV1 to FVC. We used American Thoracic 

Society criteria for acceptability and repeatability [Miller et al. 2005]. 

We used a volume spirometer (dry rolling seal spirometer) to measure exhaled air volume 

and flow rates. We used equations for predicted values and lower limits of normal derived 

from NHANES III data to define abnormal spirometry [Hankinson et al. 1999]. We defined 

obstruction as an FEV1/ FVC ratio less than the lower limit of normal with FEV1 less than the 

lower limit of normal; restriction as a normal FEV1/FVC ratio with FVC less than the lower 

limit of normal; and mixed obstruction and restriction as having FEV1, FVC, and FEV1/FVC 

ratio all less than the lower limit of normal. We used the FEV1 percent predicted to categorize 

such abnormalities as mild, moderate, moderately severe, severe, or very severe [Pellegrino 

et al. 2005]. 

Impulse Oscillometry

Many occupational lung diseases (e.g., chronic obstructive pulmonary disease (COPD), 

asthma) involve the small airways; however, this part of the lung is difficult to evaluate noninvasively. Oscillometry is a helpful technology to understand the effects of occupational 

exposures on the small airways. There are no contraindications to the test as this test is 

conducted using regular breathing and does not require a forceful exhalation [Smith et al. 

2005]. Spirometry can be normal despite respiratory symptoms or evidence of small airways 

disease on lung biopsy [King et al. 2011; Oppenheimer et al. 2007]; therefore, oscillometry 

results complement spirometry and can be used when spirometry is not possible because of a 

contraindication.

We used an impulse oscillometry machine (CareFusion Corp., San Diego, CA) to measure 

resistance (R), the energy required to propagate the pressure wave through the airways, 

and reactance (X), which reflects the viscoelastic properties of the respiratory system. The 

impulse oscillometry testing machine sends sound waves called pressure oscillations at 

different frequencies (e.g., 5 Hertz and 20 Hertz) into the airways to measure how airways 

respond to these small pressures. The test calculates 1) the airway resistance at different 

frequencies including 5 Hertz (R5) and 20 Hertz (R20), and the difference between R5 

and R20 (DR5-R20); 2) the reactance at different frequencies including 5 Hertz (X5); 3) 

resonance frequency (Fres) which is the frequency where there is no airway reactance; and 

4) the total reactance (AX) at all frequencies between 5 Hertz and the Fres. The predicted 

values for R and X were based on sex and age according to references values recommended 

by the manufacturer [Vogel and Smidt 1994]. R5 was considered abnormal (elevated) if 

the measured value was equal to or greater than 140 percent of the predicted R5. X5 was 

considered abnormal (decreased) if the value of the predicted X5 minus measured X5 was 

equal to or greater than 0.15 kilopascals per liter per second (kPa/(L/s)) DR5-R20 values 

greater than 30% were considered abnormal and evidence of frequency dependence [Smith 

2015]. We interpreted the test as normal if both the R5 and X5 were normal [Smith 2015]. 

We defined possible large (central) airways abnormality as a normal X5 and elevated R5 
Health Hazard Evaluation Report 2016-0012-3302 Page 15

with no evidence of frequency dependence. We defined a possible small airways abnormality 

if there was evidence of frequency dependence and/or a decreased X5 with or without an 

elevated R5. We defined possible combined small (peripheral) and large (central airways) 

abnormality as a decreased X5 and elevated R5 with no evidence of frequency dependence.

Bronchodilator Reversibility Testing for Impulse Oscillometry and Spirometry

If a participant had abnormal impulse oscillometry or spirometry, we repeated both tests after 

the participant received a bronchodilator inhaler medication (i.e., albuterol), which can open 

the airways in some individuals (e.g., asthmatics). For oscillometry, we defined reversibility 

(improvement) after bronchodilator administration as a decrease of at least 20% of either Fres 

or R5 or a decrease of 40% for AX. For spirometry, we defined reversibility (improvement) 

as increases of at least 12% and 200 mL for either FEV1 or FVC after bronchodilator 

administration.

Fractional Exhaled Nitric Oxide (FeNO) 

We used the NIOX MINO® device (Aerocrine Inc., Morrisville, NC) to measure the amount 

of nitric oxide in the air the participant breathed out. Nitric oxide is a gas that is produced by 

the airways, and elevated levels can be a sign of eosinophilic airway inflammation in asthma 

[Dweik et al. 2011]. In adults, fractional nitric oxide concentration in exhaled breath levels 

above 50 ppb are considered elevated. In adults with asthma, elevated levels may indicate 

that their asthma is uncontrolled [Dweik et al. 2011].

Statistical Analysis

Industrial Hygiene Survey and Ventilation Assessment

We performed analyses using Excel (Microsoft®, Redmond, WA) and SAS version 9.3 (SAS 

Institute, Cary, NC). When the values presented in the report are from samples below the 

LOD they are denoted by a “<” symbol.

Medical Survey

We calculated frequencies and standardized morbidity ratios (SMRs) and their associated 

95% confidence intervals (CIs) using SAS version 9.3 (Cary, NC). The SMRs compare 

prevalences of symptoms and spirometric abnormalities among participants with expected 

prevalences of a sample of the general population reflected in the NHANES III (1988–1994, 

symptom data) and NHANES 2007–2012 (symptom data) adjusting for sex, race/ethnicity, 

age (less than 40 years old or 40 years or greater), and cigarette smoking categories (ever/

never). For comparisons with the U.S. population, we used the most recent NHANES survey 

available for the specific comparisons. 

Results

All results tables are located in Appendix A.

Industrial Hygiene Survey

Personal and Area Full-shift Air Sampling Results
Page 16 Health Hazard Evaluation Report 2016-0012-3302

OSHA Methods 1013/1016

Table A1 presents the personal and area full-shift air sampling results. Twenty-seven 

employees participated in the personal sampling. We collected 88 personal and 96 area 

full-shift samples. Four of the area samples were collected outside the facility. Sixty-nine 

(78%) of 88 personal air samples exceeded the NIOSH REL for diacetyl of 5.0 ppb. Workers 

performing duties in grinding, packaging, roasting, and in the general production area had 

full-shift samples that exceeded the NIOSH REL for diacetyl the majority of the time. Seven 

of 88 personal air samples (8%) exceeded the NIOSH REL for 2,3-pentanedione of 9.3 ppb. 

Eighty-four of 88 personal air samples (95%) had 2,3-hexanedione concentrations below the 

analytical method LOD. The maximum concentration of 2,3-hexanedione measured was 0.3 

ppb. 

Overall, employees in packaging had the highest average personal exposure to diacetyl of 

13.2 ppb (range for 38 samples: 1.6 ppb–25.6 ppb). Thirty-seven (97%) of the 38 full-shift 

personal samples on packaging employees exceeded the NIOSH REL for diacetyl by as 

much as five times. The only full-shift personal sample below the NIOSH REL for diacetyl 

was 1.6 ppb on an employee working the can line. There was no obvious reason for this 

result to differ from the other samples. Employees in roasting had the second highest average 

personal exposure to diacetyl of 13.1 ppb. Ten of the 11 roaster employee measurements 

(91%) exceeded the NIOSH REL for diacetyl (range: 4.4 ppb–19.2 ppb). All of the fullshift personal samples on an employee in grinding (range for 4 samples: 10.3 ppb–13.8 

ppb) exceeded the NIOSH REL for diacetyl. Full-shift samples for diacetyl for employees 

performing duties in the production area including maintenance and forklift/receiving (4 

samples) ranged from 5.0 ppb–10.4 ppb; quality control laboratory (12 samples) ranged from 

1.9 ppb–16.8 ppb; and production offices including production supervisor (9 samples) ranged 

from 1.4 ppb–8.1 ppb. Personal full-shift measurements were lowest on employees at the 

front desk (2 samples) and in 2nd floor offices (5 samples) ranging from 0.5 ppb–4.04 ppb; all 

were below the NIOSH REL for diacetyl.

Seven of the 88 full-shift personal samples (8%) exceeded the NIOSH REL of 9.3 ppb for 

2,3-pentanedione. Samples exceeding the REL included four collected on employees in 

packaging, two in roasting, and one in the quality control laboratory. Almost all (85/88) of 

the full-shift personal samples results for 2,3-hexanedione were below the method LOD. 

Area samples were collected in 20 locations throughout the facility. The highest full-shift 

area samples were collected in grinding (ranges for eight samples: 12.0 ppb–68.9 ppb for 

diacetyl and 5.2 ppb–31.4 ppb for 2,3-pentanedione). The roasting area had the second 

highest levels of diacetyl and 2,3-pentanedione (ranges for 12 samples: 7.5 ppb–37.8 ppb 

for diacetyl and 3.7 ppb–23.0 ppb for 2,3-pentanedione). The packaging area had the third 

highest levels of diacetyl ranging from 5.9 ppb–21.6 ppb and 2,3-pentanedione ranging from 

2.3 ppb–17.1 ppb. Within packaging, the pillow line sample had the highest concentrations 

of diacetyl (21.6 ppb) and 2,3-pentanedione (17.1 ppb). The quality control laboratory area 

samples ranged from 7.7 ppb–11.7 ppb for diacetyl. Samples within the general production 

area ranged from 1.3 ppb–13.5 ppb for diacetyl. The general production area sample 

collected in the finished product shelving had the highest concentrations of diacetyl (range: 
Health Hazard Evaluation Report 2016-0012-3302 Page 17

9.1 ppb–13.5 ppb) while the general production area sample collected at the loading dock 

had the lowest concentration of diacetyl (range: 1.3 ppb–7.1 ppb). The area samples collected 

in the kitchen, 2nd floor sales offices, and 2nd floor library had the lowest concentrations of 

diacetyl (range: 0.5 ppb–3.2 ppb) and 2,3-pentanedione (range: <0.2 ppb–1.5 ppb). We note 

NIOSH RELs are intended to be directly compared with personal full-shift measurements; 

therefore, an area air sample exceeding a NIOSH REL is only an indication of potential 

personal exposures.

Task-based Air Sampling Results

OSHA Method 1013/1016

Table A2 presents the personal task-based air concentrations by individual task. Importantly, 

tasks associated with coffee processing are varied and as such the duration also varies. We 

collected 108 personal task-based air samples using OSHA Methods 1013/1016, and the 

sample duration ranged from three minutes–24 minutes. Sixty-two of the tasks sampled 

lasted for 15 minutes, allowing for their results to be compared directly with the NIOSH 

STELs for diacetyl (25 ppb) and 2,3-pentanedione (31 ppb). 

Employees who performed re-work of packaged coffee had the highest exposure to diacetyl 

(range for four samples: 11.9 ppb–69.9 ppb) and 2,3-pentanedione (range: 8.7 ppb–39.2 ppb). 

Each of the four rework task samples lasted 15 minutes, allowing for comparison with the 

NIOSH STELs. Three of the 15-minute samples exceeded the NIOSH STEL for diacetyl, and 

one of the samples exceeded the NIOSH STEL for 2,3-pentandione. Employees who moved 

roasted beans or ground coffee had the second highest exposure to diacetyl (range for four 

samples: 4.5 ppb–56.9 ppb) and 2,3-pentanedione (range: 2.0 ppb–24.4 ppb). Employees that 

ground coffee had the third highest exposure to diacetyl (range for 10 samples: 15.5 ppb–

52.6 ppb). Six of the grinding task samples lasted 15 minutes, and three of these exceeded 

the NIOSH STEL for diacetyl of 25 ppb. Two grinding task samples were collected for 16 

minutes, and their diacetyl concentrations were 31 ppb and 46.8 ppb, both of which are over 

the NIOSH STEL of 25 ppb for diacetyl. No grinding task samples exceeded the STEL for 

2,3-pentanedione. 

There were 39 samples taken during packaging tasks where diacetyl concentrations ranged 

from <0.9 ppb to 42.2 ppb for diacetyl. Five 15-minute samples exceeded the NIOSH STEL

for diacetyl of 25 ppb. No packaging task samples exceeded the STEL for 2,3-pentanedione. 

One packaging task sample lasted for 14 minutes. When we assume zero exposure for the 

remaining minute of the sample, the calculated concentration exceeds the NIOSH STEL of 

25 ppb for diacetyl. Employees roasting coffee had measured exposures to diacetyl (range 

for 19 samples: 1.7 ppb–32.8 ppb); one 15-minute sample exceeded the NIOSH STEL for 

diacetyl. 

Evacuated Canisters

Instantaneous Canister Task-based sampling Results

Table A3 presents the personal task-based air concentrations from the evacuated canister 

sampling. We collected 36 personal task-based canister air samples. Because of the very short 

duration of the samples, results should not be compared with the 15-minute STELs. 
Page 18 Health Hazard Evaluation Report 2016-0012-3302

The instantaneous task sample collected in the breathing zone of a packaging employee 

while loading ground coffee into a hopper on the pillow pack line had the highest level 

of diacetyl (3,765 ppb) and 2,3-pentanedione (3,377 ppb), and the second highest level 

of 2,3-hexandione (96 ppb). The second highest levels of diacetyl (2,692 ppb) and 

2,3-pentandione (949 ppb) were measured in an instantaneous task sample collected in 

the breathing zone of an employee during the removal of a supersack full of ground coffee 

from the grinder. Other instantaneous task samples collected during tasks associated with 

grinding also had relatively high levels of diacetyl (369–1,279 ppb) and 2,3-pentanedione 

(163–408 ppb). The third highest levels of diacetyl (2,146 ppb) and 2,3-pentanedione (743 

ppb) were observed when an employee dumped French Roast whole beans into a hopper on 

the blending line. The 2,3-hexanedione level of 106 ppb in this sample was the highest of all 

samples.

We collected 17 instantaneous canister samples during a variety of tasks in the quality control 

laboratory including grinding and cupping. Concentrations of diacetyl ranged from 9 ppb–74 

ppb, and 2,3-pentanedione ranged from 7 ppb–44 ppb. 2,3-Hexanedione concentrations were 

lower, ranging from <0.9 ppb–6 ppb. The highest diacetyl and 2,3-pentanedione levels were 

associated with grinding coffee beans.

Thirteen samples were taken during tasks in the roasting area including grinding samples 

of roasted coffee for quality control and checking the roast profile. Diacetyl levels (range: 

18 ppb–98 ppb) and 2,3-pentanedione levels (range: 10 ppb–101 ppb) were higher in 

tasks where an employee ground samples of roasted coffee for quality control checks. 

2,3-Hexanedione levels were less than the analytical method LOD for most samples.

Source Canister Sampling Results

Table A4 presents instantaneous source air sampling results using evacuated canisters. We 

collected 43 source canister air samples. The three samples with the highest concentrations 

of diacetyl, 2,3-pentanedione, and 2,3-hexanedione were all associated with ground coffee. 

The sample with the highest concentrations was collected at a supersack of ground coffee 

on the ICA packaging line 10 minutes after the coffee had been ground (diacetyl 26,406 

ppb, 2,3-pentanedione 13,139 ppb, and 2,3-hexandione 378 ppb). The second highest 

sample concentrations were measured in a sample collected during grinding of a supersack 

of Breakfast Blend (diacetyl 11,160 ppb, 2,3-hexanedione 2739 ppb, and 2,3-hexanedione 

272 ppb). The third highest concentrations were from a sample taken at the opening of 

a supersack in the off-gassing area approximately two hours after the coffee was ground 

(diacetyl 10,541 ppb, 2,3-pentanedione 4,123 ppb, and 2,3-hexanedione 205 ppb). The 

instantaneous source samples collected at the main grinder and at the grinders (sample 

and espresso) in the quality control laboratory tended to have higher concentrations of 

diacetyl, 2,3-pentanedione, and 2,3-hexanedione. A sample taken at the espresso grinder 

had 809 ppb diacetyl, 679 ppb 2,3-pentanedione, and 27 ppb 2,3-hexanedione while a 

sample taken pulling espresso shots had 467 ppb diacetyl, 430 ppb 2,3-pentanedione, and 

17 ppb 2,3-hexanedione. A sample taken on the can packaging line where the beans enter 

the can had 2,086 ppb diacetyl, 823 ppb 2,3-pentanedione, and 83 ppb 2,3-hexanedione. All 
Health Hazard Evaluation Report 2016-0012-3302 Page 19

14 instantaneous source samples collected at the roasters and roaster sample grinders had 

diacetyl and 2,3-pentanedione levels below 100 ppb. 

Background Pre- and Post-Shift Diacetyl and 2,3-Pentanedione Canister Results

Table A5 presents the instantaneous evacuated canister pre- and post-shift background air 

sampling results on Tuesday, April 20, 2016, and Thursday, April 22, 2016. Samples were 

collected in the middle of the production area and between the staging and green bean 

storage areas on both days. Air concentrations of diacetyl and 2,3-pentanedione increased 

over the course of the day on both dates. Both pre- and post-shift concentrations for diacetyl 

and 2,3-pentanedione were higher on April 20 than on April 22 at both sampling locations. 

The pre-shift diacetyl concentration on April 20 in the middle of the production area was 

11.8 ppb, and the post-shift concentration was 25.5 ppb. The pre-shift 2,3-pentanedione 

concentration was 4.2 ppb, and the post-shift concentration was 8.4 ppb. On April 22, the 

pre-shift diacetyl concentration in the middle of the production area was 5.9 ppb, and the 

post-shift concentration was 20.3 ppb. The pre-shift 2,3-pentanedione concentration was 2.0 

ppb, and the post-shift concentration was 7.3 ppb.

The post-shift concentrations of diacetyl and 2,3-pentanedione in the samples collected 

between the staging and green bean storage area were also higher on April 20 than on 

April 22. The pre-shift diacetyl concentration on April 20 was 9.9 ppb, and the post-shift 

concentration was 38.2 ppb. The pre-shift 2,3-pentanedione concentration was 3.5 ppb, and 

the post-shift concentration was 20.1 ppb. On April 22, the pre-shift diacetyl concentration 

between the staging and green bean storage area was 5.6 ppb, and the post-shift concentration 

was 19.3 ppb. The pre-shift 2,3-pentanedione concentration was 2.6 ppb, and the post shift 

concentration was 8.6 ppb. The 2,3-hexanedione concentrations in all samples were always 

less than 2.0 ppb.

Bulk Samples and Headspace Results

Table A6 presents the results from 11 bulk samples of whole bean and ground coffee using 

headspace analysis. There was one sample of ground coffee collected from a supersack on a 

packaging line on April 21, 2016. Each of the five whole bean samples with a corresponding 

ground bean sample were collected on April 22, 2016. Both diacetyl and 2,3-pentanedione 

concentrations were always higher in the whole bean sample than in the ground sample. 

2,3-Pentanedione concentrations were higher than the diacetyl concentrations in both the 

whole bean and ground samples of the dark medium Honduran, medium Mexican, and Full 

City Peru Decaf. 2,3-Hexanedione results were below the method LOD in eight of the 11 

samples. The 2,3-hexanedione concentration (300.8 ppb) in one of three samples with results 

above the LOD was greater than 2,3-pentanedione concentration and similar to the diacetyl 

concentration.

Real-time Monitoring: Temperature, Relative Humidity (RH), Carbon Dioxide (CO2), Carbon 

Monoxide (CO), and Total Volatile Organic Compounds (TVOCs)

During sampling April 19–22, 2016, the outdoor temperatures ranged from 46°F–81°F, and 

the outdoor RH ranged from 25%–87%. Overall temperature and RH ranges in the main 

production area were 63°F–80°F and 18%–48%, respectively. Temperatures in the quality 
Page 20 Health Hazard Evaluation Report 2016-0012-3302

control laboratory were slightly warmer ranging from 74°F–82°F, with RH ranging from 

22%–42%. Temperature and RH in the second floor sales and library area ranged from 

69°F–76°F and 22%–39%, respectively.

Table A7 presents results from real-time monitoring of CO2, CO, TVOCs, temperature and 

relative humidity. Throughout the week of collection, outdoor CO2 levels ranged from 358 

ppm–380 ppm, and outdoor CO levels ranged from 0 ppm–0.3 ppm. Average CO2 levels were 

highest at the roaster sample grinders (794 ppm) and behind the main grinder (770 ppm). 

Average CO (25.7 ppm) was highest to the left of the discharge chute (25.7 ppm) at the main 

grinder and ranged from 1.4 ppm–7.7 ppm in the other locations. Average levels of TVOCs 

were highest to the left of the discharge chute at the main grinder (3,270 ppb) and lowest in 

the off gassing area (735 ppm).

Our real-time monitoring demonstrated the highest peak measurements of CO and CO2

occurred at the main grinder on the second day of sampling (4/20/2016). On the first day 

of sampling (4/19/2016), the area basket with the monitors at the grinder was located to the 

right of the ground coffee discharge chute next to the grinder control panel. An estimated 

3,850 pounds of coffee was ground, and the average CO concentration was 7.7 ppm, and the 

average CO2 concentration was 596 ppm. We noticed the air was moving across the monitor 

to the left. On the second day of sampling (4/20/2016), we moved the area sampling basket 

to the other side of the grinder so it was positioned to the left of the discharge chute. An 

estimated 3,150 pounds of coffee was ground. The average CO concentration was 25.7 ppm, 

and the average CO2 concentration was 749 ppm. On the third day of sampling (4/21/2016), 

we placed the area sampling basket behind the grinder next to the grinder operator desk. An 

estimated 2,450 pounds of coffee was ground. The average CO concentration was 6.6 ppm, 

and the average CO2 concentration was 770 ppm.

Figure 1. Carbon monoxide (CO) and carbon dioxide (CO2) 

concentrations during sampling on April 20, 2016, to the left of the 

discharge chute at the main grinder.
Health Hazard Evaluation Report 2016-0012-3302 Page 21

On April 20, 2016, NIOSH staff recorded activities taking place at the main grinder while 

continuous monitoring devices were recording CO2, CO, and TVOC levels. The area basket 

with the samplers was positioned to the left of the grinder at breathing zone height. Figure 1 

shows the CO2 and CO levels during the sampling period. Each of the peaks corresponds

with times when batches of coffee were being ground. The first peak was generated during 

grinding of approximately 100 pounds. The remaining peaks were associated with grinding 

larger batches. CO2 concentrations ranged from 433 ppm to >5,000 ppm (average 749 ppm), 

and the CO concentrations ranged from 0.8 ppm to >500 ppm (average 25.7). The instrument 

was only capable of recording CO2 up to 5,000 ppm and CO up to 500 ppm. CO2 levels 

exceeded 5,000 ppm twice while CO levels exceeded 500 ppm 36 times. 

The TVOC peaks overlapped with the CO peaks. The average TVOC concentration was 

3,270 ppb with a maximum reading of 71,819 ppb. The maximum reading occurred when a 

supersack of ground coffee was removed from the discharge chute of the grinder, tied closed, 

and moved to the packaging line. 

On April 20, 2016, an area sampler was positioned at the red roaster (Probat G-120). CO 

concentrations ranged from 0 ppm–44 ppm (average 3.9 ppm), and CO2 ranged from 446 

ppm–1,045 ppm (average 666 ppm). 

Figure 2 shows the CO and TVOC concentrations at the red roaster. The average TVOC 

concentration at the red roaster was 1,008 ppb with a maximum reading of 3,066 ppb.

Figure 2. Carbon monoxide (CO) and total volatile organic compound 

(VOC) concentrations at the red roaster on April 20, 2016.

Figure 3 overlays the CO measurements at the main grinder and the red roaster. The majority 

of the red roaster peaks coincide with the main grinder peaks. Figure 4 overlays the TVOC 

measurements at the main grinder and the red roaster. The TVOC levels at the red roaster 

also correspond with the TVOC levels at the main grinder.
Page 22 Health Hazard Evaluation Report 2016-0012-3302

Figure 3. Carbon monoxide (CO) concentrations at the main grinder and at 

the red roaster on April 20, 2016.

Figure 4. Total volatile organic compound (VOC) concentrations at the 

main grinder and the red roaster on April 20, 2016.

Personal Exhaled Carbon Monoxide (CO) Measurements

Twenty-seven employees provided breath samples for measurement of CO by exhaling into 

a monitor at various times during the workday. Measurements were typically collected at 

the beginning of the shift, lunch break, and at the end of the shift. After exhaling into the 

monitor, the device reported a CO value in ppm and also calculated an estimated COHb 

percentage. The overall average CO level was 2.1 ppm (range: 0 ppm–15 ppm), and COHb 

was 0.8% (0%–3%). Average CO level in smokers was 4.9 ppm (range: 0 ppm–15 ppm), and 

COHb was 1.4% (range: 0%–3%). All COHb test results in non-smokers were below 2.2%, 

and in smokers were below 3%.
Health Hazard Evaluation Report 2016-0012-3302 Page 23

Ventilation Assessment

Two large makeup air units on the roof of the production space were used periodically to 

bring fresh air into the facility. The units were generally turned on during the early mornings 

of our visit, but were turned off for the majority of the days we were onsite. These units 

were reportedly used more in the winter to provide some heat to the facility, and almost 

never during the summer months. Ceiling fans were in use in the production area during our 

sampling.

Differential pressure measurements taken with the rooftop makeup air units off indicated 

the majority of adjacent spaces were generally neutral to the production space. The two 

exceptions were the receiving office and the procurement office, which were both slightly 

positive to production. However, when the makeup air units were on, the majority of adjacent 

spaces were under slightly negative pressure to production (the receiving office and the 

procurement office both remained positive). This means air from the production space can be 

pushed into the negative-pressure adjacent spaces when the makeup air units are operating, at 

least under the conditions when our pressure measurements were taken. The non-production 

spaces of the facility are served by six rooftop air-handling units. Different combinations of 

operating states of those units (i.e., which ones are on and off simultaneously) on the nonproduction side of the plant could make the pressure differentials better or worse.

Other Observations

We observed some employees having difficulty untying the closures on the supersacks. 

Although we did not collect task samples during this activity, during these periods, the 

employees had the potential to be exposed to peaks of diacetyl and 2,3-pentanedione while in 

position near the opening of the supersack containing roasted coffee. 

We observed some employees in the roaster and grinder areas wearing hearing protection 

while employees working in close proximity in the packaging areas were not wearing hearing 

protection. Although we did not conduct noise exposure monitoring during our visit, it is 

possible sound levels might exceed the OSHA PELs, the OSHA action level, or the NIOSH 

REL for noise [29 CFR 1910.95; NIOSH 1998]. Noise seemed to be especially loud when the 

grinder, green bean induction hoppers, and roaster destoners were operating simultaneously. 

In our initial interim letter dated May 10, 2016, we recommended an evaluation of noise 

levels to determine if a more formal hearing protection program was necessary.

Medical Survey Results

Demographics

Seventy-nine of 94 onsite employees (84%) participated in the medical survey. Of these, 

26 employees worked at the offsite location. The majority of participants were male (54%) 

and white (67%), with a mean age of 41 years (range 19 years–72 years) and average tenure 

at the company (including previous locations) of eight years (range: 2 months–30 years). 

Thirty-one (39%) participants were current or former smokers. 

Forty-seven (59%) participants reported ever spending time in the production area. Of these; 

18 (38%) spent more than 32 hours per week in the production area. The mean time reported 
Page 24 Health Hazard Evaluation Report 2016-0012-3302

being spent in the production area per week was 16.7 hours (range: 0.1 hours–50 hours). 

Employees reported being within an arm’s length of the following exposures: an operating 

production coffee roaster (n=19, 24%); cooling bins that contain roasted beans while they are 

cooling (n=20, 25%), an operating production grinder (n=19, 24%); and packaging of coffee 

(n=30, 38%). 

Symptoms and Self-Reported Diagnoses

The prevalences of symptoms over the last year and last four weeks at the time of the survey 

are listed in Table A8. Nose symptoms (n=57, 72%) were the most commonly reported, 

followed by eye symptoms (n=43, 54%). Wheeze (n=18, 23%) and breathing trouble (n=18, 

23%) were the most commonly reported lower respiratory symptoms. The prevalence of 

symptoms between participants who reported working at the main facility and the offsite 

location was similar (data not shown). Sixteen (20%) and 11 (14%) participants reported 

their nose and eye symptoms were aggravated by work, respectively. Of the 18 participants 

who reported wheezing, 12 reported their wheezing was the same away from the workplace, 

two reported their wheezing was worse away from the workplace, and four reported their 

wheezing was better away from the workplace. Two of the four participants who reported 

their breathing was better away from the workplace worked in production. Three participants 

reported their breathing trouble was better away from the workplace; one of the three 

participants worked in production. Some production employees noted their nose and sinus 

symptoms were caused or aggravated by green coffee bean dust, chaff, and ground coffee. 

Twenty-two participants reported a diagnosis of hay fever or nasal allergies; among these, 

seven reported the diagnosis was made post-hire. Thirteen participants reported ever having 

received a diagnosis of asthma; two received the diagnosis post-hire. 

The prevalences of symptoms over the last year at the time of the survey for employees who 

reported spending any time in production areas (n=47) and for employees who reported not 

spending any time in production areas (n=32) are listed in Table A9. Overall, the prevalence 

of nose, eye, lower respiratory, and systemic symptoms were comparable between employees 

who reported spending time in production areas and employees who did not spend time in 

production areas.

Medical Tests

Twenty participants had at least one breathing test interpreted as abnormal. Among these, 

four (20%) were current smokers, six (30%) were former smokers, and 11 (55%) reported 

ever working in the production area. No spirometry tests were interpreted as abnormal. Ten 

impulse oscillometry tests were interpreted as consistent with a small airway abnormality, 

two with a large airway abnormality, and three with small and large airway abnormalities. 

Fourteen of the 15 participants with impulse oscillometry tests interpreted as abnormal 

were given bronchodilator, and five had significant improvement in impulse oscillometry. 

Six exhaled nitric oxide tests were interpreted as elevated. Three of the six participants 

with elevated nitric oxide tests reported ever working in production. Two participants with 

abnormal exhaled nitric oxide tests had current asthma. 
Health Hazard Evaluation Report 2016-0012-3302 Page 25

NHANES Comparison of Symptoms, Diagnoses, and Spirometry

The SMRs for stuffy, itchy, or runny nose (SMR=1.3); phlegm production for three 

consecutive months (2.3); wheezing (1.7); ever having received a physician diagnosis of 

asthma (2.2); and currently having a physician diagnosis of asthma (2.6) were elevated (Table 

A10). SMRs for eye symptoms, sinus problems, shortness of breath on exertion, and cough 

were not elevated. 

Discussion

Diacetyl, 2,3-pentanedione, 2,3-hexanedione, other VOCs, and other chemicals such as CO 

and CO2 are naturally produced when coffee beans are roasted, and grinding the roasted 

coffee beans produces greater surface area for the off-gassing of these chemicals [Anderson 

et al. 2003; Akiyama et al. 2003; Daglia et al. 2007; Newton 2002; Nishimura et al. 2003; 

Raffel and Thompson 2013]. Occupational exposure to diacetyl and 2,3-pentanedione can 

cause loss of lung function and the lung disease obliterative bronchiolitis [NIOSH 2016]. 

Alpha-Diketones

Personal Air Sampling

Average air concentrations of diacetyl and 2,3-pentanedione in this facility were compared 

with their respective NIOSH RELs of 5.0 ppb and 9.3 ppb. The majority (78%) of personal 

full-shift diacetyl exposures were above the NIOSH REL of 5.0 ppb, and 88% were above 

the NIOSH AL for diacetyl of 2.6 ppb. The highest average personal exposures to diacetyl 

were in packaging employees (13.2 ppb), roasting employees (13.1 ppb), and an employee 

performing grinding (11.8 ppb). Eighteen of 28 (64%) full-shift samples on employees 

performing duties in the general production area, production office, and quality control 

laboratory also had results that exceeded the REL for diacetyl. Eight percent of the personal 

full-shift samples were above the NIOSH REL of 9.3 ppb for 2,3-pentanedione. These seven 

personal full-shift samples were collected on employees in roasting (two samples), the 

quality control laboratory (one sample), and on the packaging lines (four samples). Personal 

full-shift samples from employees in the second floor offices and at the front desk did not 

exceed either REL.

As noted earlier, the REL should be used as a guideline to indicate when steps should be 

taken to reduce exposures in the workplace. The risks associated with the measured levels 

are higher than NIOSH recommends. As described in the quantitative risk assessment 

from the NIOSH Criteria Document (Table 5-27) [NIOSH 2016], after a 45-year working 

lifetime exposure to 20 ppb (a concentration lower than the highest concentration (26 ppb) 

measured at this facility), NIOSH estimated that 3 in 1,000 workers would develop reduced 

lung function (FEV1 below the 5th percentile). NIOSH predicted that around 5 in 10,000 

workers exposed to diacetyl at 20 ppb would develop more severe lung function reduction 

(FEV1 below 60% predicted, defined as at least moderately severe by the American Thoracic 

Society [Pellegrino et al. 2005]). After a 45-year working lifetime exposure to 50 ppb (a 

concentration higher than the highest concentration measured at this facility), NIOSH 
Page 26 Health Hazard Evaluation Report 2016-0012-3302

estimated that 8 in 1,000 workers would develop reduced lung function (FEV1 below the 5th 

percentile). NIOSH predicted that 12 in 10,000 workers exposed to diacetyl at 50 ppb would 

develop more severe lung function reduction. The effects of a working lifetime exposure at 

26 ppb would be between those for 20 ppb and 50 ppb. NIOSH recommends keeping diacetyl 

concentrations below 5 ppb because at this level, the risk of reduced lung function after a 

working lifetime of exposure is below 1 in 1000 workers. NIOSH recommends taking steps 

to reduce diacetyl exposures to below the REL of 5 ppb whenever possible.

Area Air Sampling

The highest area samples for diacetyl and 2,3-pentanedione were in the grinding, roasting, 

and packaging areas. Although lower, diacetyl and 2,3-pentandione concentrations in eight 

other locations within the production area and in the quality control laboratory were also 

elevated. The area samples collected in the kitchen area and second floor offices and library 

space had the lowest concentrations. Of the 96 full-shift area samples, 76 (79%) were above 

the NIOSH REL for diacetyl and 12 (13%) above the REL for 2,3-pentanedione. We note 

NIOSH RELs are intended for personal full-shift measurements; however full-shift area air 

samples exceeding the RELs can be an indicator for areas with potential personal exposures. 

Overall, 2,3-hexanedione concentrations were low with only four personal and three area 

samples results above the LOD.

Task-Based Exposures

Coffee processing involves multiple tasks that can cause intermittent exposure to diacetyl and 

2,3-pentanedione. Traditional full-shift sampling will not characterize these intermittent peak 

exposures. Evaluating intermittent and task-based exposures to diacetyl and 2,3-pentanedione 

is difficult with current validated sampling methods (OSHA Methods 1013/1016). Because 

tasks are sporadic in coffee processing, with some only lasting a few seconds or minutes, 

we used instantaneous evacuated canisters to sample tasks that lasted only a few seconds to 

minutes and OSHA Methods 1013/1016 for longer duration tasks. We sampled by task, with 

varying durations, to understand which tasks might have contributed to higher exposures to 

diacetyl and 2,3-pentanedione.

Sixty-two samples with a duration of 15-minutes were compared with the NIOSH STELs 

for diacetyl (25 ppb) and 2,3-pentanedione (31 ppb) (Table A2). Rework of packaged coffee 

had the highest exposure with three of the four samples exceeding the diacetyl STEL and 

one exceeding the 2,3-pentanedione STEL. Three task samples taken during grinding, five 

samples during coffee packaging, and one sample during roasting, exceeded the diacetyl 

STEL. 

We also used instantaneous evacuated canisters to sample tasks with short duration. 

These samples were collected by placing the inlet of the canister near the breathing zone 

of an employee while they performed a task. Four of the highest instantaneous sample 

results for both diacetyl and 2,3-pentanedione were associated with ground coffee (Table 

A3). Loading ground coffee into a hopper on the pillow pack line in packaging had the 

highest concentration of diacetyl (3,765 ppb) and 2,3-pentandione (3,377 ppb). Removing 

supersacks of ground coffee from the grinder and sealing the supersack resulted in diacetyl 
Health Hazard Evaluation Report 2016-0012-3302 Page 27

concentrations of 369 ppb to 2,692 ppb and 2,3-pentanedione of 163ppb to 949 ppb. The 

greater surface area created from grinding might have contributed to these concentrations 

[Akiyama et al. 2003]. Concentrations of diacetyl (2,146 pbb) and 2,3-pentanedione (743 

ppb) were measured while dumping whole bean roasted coffee into a hopper along the 

blending line. This sample also had the highest measured concentration of 2,3-hexanedione 

of 106 ppb.

In addition to tasks, we used evacuated canisters to collect samples at specific pointsources (Table A4). For these samples, the inlet of the flow controller was placed directly 

at the source of interest. As with the task-based samples, the diacetyl and 2,3-pentanedione 

concentrations were highest at sources where ground coffee was present. The highest sample 

for diacetyl (26,406 ppb) and 2,3-pentanedione (13,139 ppb) was measured at a supersack 

of freshly ground coffee on the ICA packaging line. Seven samples collected at the grinder 

had diacetyl concentrations ranging from 15.4 ppb–11,160 ppb and 2,3-pentanedione 

concentrations from 7.8 ppb–2,739 ppb. In the QC laboratory, the highest concentrations 

were also measured at the espresso grinder while pulling shots of espresso.

Instantaneous samples collected at the beginning of production and at the end of production 

in the same two locations on April 20, 2016, and April 22, 2016, demonstrated the 

concentrations of diacetyl, 2,3-pentanedione and 2,3-hexanedione increased throughout the 

day (Table A5). This indicates that the generation rate of these compounds exceeded the rate 

at which existing ventilation systems removed them under the conditions when samples were 

taken. 

Bulk Samples

Diacetyl isn’t found in green beans and forms later in the coffee roasting process [Daglia 

et al. 2007]. We observed higher levels of diacetyl and 2,3-pentanedione in the whole bean 

samples than in the ground samples. Normally, we would expect ground coffee to provide 

higher levels of alpha-diketones than whole bean coffee. Thus, our observation may be the 

result of the bulk samples sitting in sealed tubes for several weeks prior to opening the tubes 

and manipulating the samples for analysis. 

Real-time Monitoring: Carbon Dioxide (CO2), Carbon Monoxide (CO), and Total Volatile 

Organic Compounds (TVOCs)

The real-time monitoring demonstrated that the highest peak measurements of CO, CO2, and 

TVOCs occurred to the left of the main grinder discharge chute while grinding was taking 

place. One employee had primary responsibility for all activities associated with grinding. 

We noted no employees spent long periods of time standing near the grinder discharge chute 

during the sampling period. No employees had elevated COHb test results. The location of 

the main grinder may allow for contaminants to be shared with other areas including roasting 

and packaging.

The roaster barrel burner intakes and the afterburner intakes for the roasters might be pulling 

contaminants from grinding toward the roasting area as illustrated by examining the realtime monitoring results for CO and total VOC concentrations (Figures 5 & 6) at the main 
Page 28 Health Hazard Evaluation Report 2016-0012-3302

grinder and red roaster on April 20, 2016. The peaks at the red roaster trend with the peaks at 

the main grinder. The same trends were evident on the following day when we examined the 

real-time monitoring results from the main grinder and from the sample grinder in roasting. 

Ventilation

As shown in Table A5, concentrations of alpha-diketones increased in the production area 

throughout the course of the day indicating these compounds were being generated faster 

than they could be removed by existing ventilation systems. We also determined air from the 

production areas could potentially enter non-production areas under the conditions of testing, 

particularly when the make-up air units were on. The operational state of various air-handling 

units and make-up air units throughout the facility could make pressure differentials better 

or worse. Loading dock doors being opened or closed will also effect pressure differentials. 

Constant negative pressure in the production area relative to non-production areas is needed 

to keep contaminants from the production space from migrating to non-production areas. To 

maintain consistent negative pressure in the production area, additional exhaust systems are 

needed. These systems could consist of local exhaust at contaminant sources, general exhaust 

fans through the walls or ceiling, or a combination of both.

Local exhaust ventilation

Local exhaust ventilation systems capture contaminants when generated and exhausts them 

before inhalation by employees occurs. Local exhaust ventilation systems generally consist 

of hoods or enclosures, duct work, or fans. Depending on the contaminant and whether air 

is recirculated, filters or other air cleaning technologies can be incorporated. When properly 

designed local exhaust ventilation systems are installed, overall workplace exposure levels 

can be reduced by removing contaminants at the source. High concentrations of alphadiketones were measured at the main grinder, at the opening of supersacks, on the can line 

in packaging, and at the espresso machine in the quality control laboratory. Work with a 

ventilation engineer to reduce alpha-diketone exposures in these locations. If exposure levels 

are still elevated after modifications have been made, it may be necessary to perform further 

sampling to identify additional point sources. 

General exhaust or dilution ventilation

In an ideal environment, good general ventilation provides fresh air into the space and 

removes contaminated air. General exhaust ventilation allows contaminants to be emitted into 

the workplace and then dilutes the concentration of the contaminant to acceptable levels. This 

is generally done by providing fresh outdoor air (or recirculated, filtered air) to the space to 

provide dilution. Simultaneously, air is exhausted from the space to remove the contaminants. 

The relationship between supply air and exhaust air flow rates can be used to help maintain 

appropriate pressure relationships. If more air is supplied than exhausted, the space will 

generally be under positive pressure, which allows contaminants to migrate from the space to 

adjacent areas. Conversely, exhausting more air than is supplied, maintains the space under 

negative pressure which helps contain the contaminants in the area where they are generated. 

During the April 2016 survey, two make-up air units capable of supplying fresh air to 

the production space were present. The systems were reportedly operated intermittently 
Health Hazard Evaluation Report 2016-0012-3302 Page 29

and seasonally, and used more in winter to provide heat. Operating the makeup air units 

consistently would help to dilute airborne concentrations of alpha-diketones, but most 

likely would not maintain concentrations below the NIOSH RELs for diacetyl and 

2,3-pentanedione. Air was only being exhausted from the production area via the roasters, 

and the quantity of air exhausted was variable depending on the operating condition of each 

roaster. If more air was exhausted, through new wall or ceiling-mounted exhaust fans, it 

would help reduce concentrations of diacetyl and 2,3-pentanedione in the production space. 

It would also aid in keeping the production area under negative pressure compared with the 

non-production areas, which is desirable. 

Relocation or enclosure of specific processes

While engineering controls are undoubtedly needed to reduce exposures, relocating processes 

or specific pieces of equipment to make control implementation easier might also reduce 

worker exposures. On April 20, 2016, we measured total VOCs at both the main grinder 

and the red roaster (Figure 6). It was clear any contaminant generation at the grinder was 

simultaneously detected at the red roaster. This demonstrates the roasters’ exhaust pulls 

contaminants generated during grinding toward that corner of the production area. Thus, 

roaster operators are likely exposed to alpha-diketone concentrations from processes other 

than roasting. Isolating the grinder in conjunction with local exhaust ventilation would likely 

reduce overall alpha-diketone exposures to employees in the production area. While it would 

be difficult to enclose the grinder in its current location, moving the grinder closer to an 

exterior wall could make it easier to enclose the grinding process and reduce costs associated 

with ventilating the process separately. Other process areas such as blending and off-gassing 

might be candidates for enclosure with separate ventilation to further reduce concentrations 

of alpha-diketones in the production area. 

In general, the current ventilation configuration in the production area should be evaluated. 

An evaluation by a qualified ventilation engineer can determine if modifications to existing 

ventilation components could be made to lower airborne concentrations and/or whether 

the installation of new equipment may be necessary. In addition to dilution ventilation, 

the installation and use of local exhaust ventilation systems to decrease concentrations of 

diacetyl and 2,3-pentanedione can be explored, and an overall, cost-effective solution can 

be developed. After making changes to production ventilation, processes, controls, or work 

practices additional air sampling should be conducted to determine the effect on exposure 

conditions within the workplace.

Medical Survey 

Overall, nose and eye symptoms were the most commonly reported symptoms. Some 

employees reported their nose and sinus symptoms were caused or aggravated by green 

coffee dust, chaff, or roasted coffee dust. Coffee dust is an organic dust and, as noted earlier, 

exposure to coffee dust is known to cause respiratory symptoms and a known risk factor for 

occupational asthma [Karr et al. 1978; Zuskin et al. 1979, 1985, 1993; Thomas et al. 1991; 

Sakwari et al. 2013].

Upper respiratory diseases such as allergic rhinitis (hay fever, nasal allergies) and sinusitis 
Page 30 Health Hazard Evaluation Report 2016-0012-3302

are sometimes associated with lower respiratory symptoms and asthma, and can precede the 

diagnosis of asthma [Shaaban et al. 2008; EAACI Task Force on Occupational Rhinitis et 

al. 2008; Rondón et al. 2012, 2017; Sahay et al. 2016]. Upper respiratory involvement (e.g., 

rhinitis, sinusitis) can result in suboptimal control of asthma. Thirty-two (84%) of the 38 

participants who reported lower respiratory symptoms also reported nasal or sinus problems 

or physician-diagnosed hay fever or nasal allergies.

Green coffee dust is thought to be a more potent allergen than roasted coffee dust because 

roasting destroys some of the allergenic activity [Lehrer et al. 1978]. As discussed in the 

recommendation section, to prevent symptoms related to green coffee dust, make N95 

disposable filtering facepiece respirators available for voluntary use for protection against 

dust exposure such as when emptying burlap bags of green beans into the storage silos feed 

hopper, cleaning the exhaust system of chaff, emptying the chaff containers, or cleaning the 

green bean storage area.

The number of participants with current physician-diagnosed asthma was approximately 

2.5 times higher than that observed in the U.S. population. Asthma symptoms often 

improve when away from exposures that trigger symptoms while other lung diseases such 

as obliterative bronchiolitis or chronic obstructive pulmonary disease (COPD) generally 

do not improve. Spirometry can be used to help detect and follow individuals with asthma 

and other lung diseases such as obliterative bronchiolitis or COPD. Spirometry can show if 

air is exhaled from the lungs more slowly than normal (i.e., obstructive abnormality) or if 

the amount of air exhaled is smaller than normal (i.e., restrictive abnormality). In asthma, 

there is intermittent airways obstruction that is reversible after treatment with bronchodilator 

medications (e.g., albuterol). In obliterative bronchiolitis, scar tissue prevents the small 

airways (bronchioles) from opening up when albuterol is given. In other words, the airways 

obstruction is fixed and not responsive (reversible) to bronchodilator medicine. The 

obstructed airways prevent rapid emptying of the lung air sacs (alveoli) during exhalation. 

This explains why the respiratory symptoms of those with occupational obliterative 

bronchiolitis do not tend to improve when away from work-related exposures; however, 

avoidance of further exposure can stop progression of the disease [Akpinar-Elci et al 2004]. 

Spirometry and impulse oscillometry measure different things. Spirometry assesses airflow 

while impulse oscillometry accesses the airways response to a sound or pressure wave. In 

general, during the impulse oscillometry test, a small pressure impulse (sound wave) is 

imposed upon the inspiratory and expiratory airflow during normal tidal breathing. This 

pressure wave causes a disturbance in the airflow and pressure, and the response of the 

airways (i.e., change in pressure to change in flow) is a measure of the resistance to airflow in 

the airways [Desiraju and Agrawal 2016]. Impulse oscillometry can be useful as an indirect 

measure of airflow obstruction and helpful in individuals not able to perform forced breathing 

maneuvers required during the spirometry test. The impulse oscillometry test has been used 

for many years to measure changes in the airways of children with lung problems such as 

asthma and cystic fibrosis [Song et al. 2008; Komarow et al. 2011; Shi et al. 2012; Schulze et 

al. 2016]. More recently, impulse oscillometry has been used to investigate lung problems in 

adults exposed to dust or chemicals, such as World Trade Center emergency responders and 
Health Hazard Evaluation Report 2016-0012-3302 Page 31

soldiers returning from deployment overseas [Oppenheimer et al. 2007; Berger et al. 2013; 

Weinstein et al. 2016]. Over the years, researchers have developed reference (predictive) 

equations for different populations of children for oscillometry [Malmberg et al. 2002; Park 

et al. 2011; Lee et al. 2012; de Assumpcão et al. 2016]. For adults, fewer reference equations 

are available for oscillometry [Vogel and Smidt 1994; Newbury et al. 2008; Schulz et al. 

2013]. The predicted values we used for oscillometry measures were based on gender and 

age according to references values recommended by the manufacturer. Unlike predictive 

equations used for spirometry, the impulse oscillometry reference equations we used did not 

take into account height, race, or smoking status [Vogel and Smidt 1994].

Our findings of upper and lower respiratory symptoms with a work-related pattern in some 

employees, an approximately two-fold excess of wheeze and phlegm production, and 

abnormalities on breathing tests in about 20% of participants suggest a burden of respiratory 

problems in this workforce. Work-related symptoms, which are symptoms that tend to 

improve away from the workplace, might reflect effects of workplace exposures that are 

reversible. However, some participants with lower respiratory symptoms such as wheeze did 

not have a work-related pattern. However, even symptoms that do not improve away from 

the workplace can be related to workplace exposures. In such cases, effects of workplace 

exposures might not be readily reversible, so the pattern of improvement away from the 

workplace is not seen and the recognition of an occupational cause can be delayed. The lower 

respiratory symptoms and the lung function abnormalities we found are not specific to a 

particular respiratory problem or disease. They could be related to workplace exposures or to 

other factors. Indeed, some employees had respiratory diagnoses that preceded employment 

at this facility. We mailed each participant their individual lung function test results with an 

explanation of the results and recommended each participant provide the information to their 

personal physician.

We recommend starting a medical monitoring program because air sampling in the main 

facility detected concentrations of diacetyl and 2,3-pentanedione above the NIOSH RELs, 

and participants were nearly two times as likely to have wheeze and over 2.5 times as likely 

to have current physician-diagnosed asthma compared with the general population. All 

production and quality control laboratory employees and any employees that assist with 

production tasks (e.g., roasting, interacting with open storage bins/containers of roasted 

coffee, grinding, weighing, or packaging coffee) should participate in the workplace medical 

monitoring program. A medical monitoring program is a means of early identification of 

employees who might be developing lung disease (e.g., asthma, obliterative bronchiolitis) 

and can help prioritize interventions to prevent occupational lung disease. The NIOSH 

medical survey results can serve as a baseline for employees who participated. In a 

workplace with risk of occupational lung disease, prevention of smoking-related lung disease 

is important and makes the detection of work-related adverse effects easier. The Centers for 

Disease Control and Prevention offers tools and resources for setting up a smoking cessation 

program [CDC 2017].
Page 32 Health Hazard Evaluation Report 2016-0012-3302

Conclusions

Full-shift personal and area air concentrations of diacetyl exceeded the NIOSH RELs in 

many areas of the facility, particularly in the packaging, grinding, and roasting. Some 

personal samples in the production office and quality control laboratory also exceeded the 

REL for diacetyl. Although fewer in number, some of the sample results also exceeded 

the REL for 2,3-pentanedione. We identified specific work tasks that resulted in air 

concentrations of diacetyl and 2,3-pentanedione that exceeded the NIOSH REL and STEL 

including re-work of packaged coffee, moving roasted whole bean or ground coffee, 

and grinding coffee. The use of real-time instruments demonstrated that the roasters 

may be pulling air from the grinder area which contains higher levels of diacetyl and 

2,3-pentanedione. Over the course of the work day, air concentrations increased within the 

general production area indicating that the current ventilation isn’t sufficient to remove the 

compounds being generated. Some recommendations are being provided to aid in reducing 

exposures and protecting respiratory health.

Overall, mucous membrane symptoms, specifically eye, nose, and sinus symptoms, were 

the most commonly reported symptoms. Some production employees reported their mucous 

membrane symptoms were caused or aggravated by green coffee dust or chaff, roasted 

coffee, or ground coffee dust. Wheezing or whistling in the chest and breathing trouble were 

the most commonly reported lower respiratory symptoms. A statistically significant twofold excess of phlegm production, wheezing, having ever received a physician diagnosis of 

asthma, and current physician diagnosis of asthma existed in the participants compared with 

the U.S. noninstitutionalized population of the same age, race/ethnicity, sex, and cigarette 

smoking distribution. No employees had abnormal spirometry results. We recommend 

a medical monitoring program to identify any employees who might be developing 

lung disease (e.g., asthma, obliterative bronchiolitis) and to help management prioritize 

interventions to prevent occupational lung disease. All production workers and employees 

that assist with production and quality control tasks (e.g., roasting, interacting with open 

storage bins/containers of roasted coffee, grinding, weighing, or packaging coffee) should 

participate in the workplace medical monitoring program.

Recommendations 

On the basis of our findings, we recommend the actions listed below. We encourage this 

coffee processing facility to use a labor-management health and safety committee or working 

group to discuss our recommendations and develop an action plan. Our recommendations 

are based on an approach known as the hierarchy of controls. This approach groups actions 

by their likely effectiveness in reducing or removing hazards. In most cases, the preferred 

approach is to eliminate hazardous materials or processes and install engineering controls to 

reduce exposure or shield employees. 

Engineering Controls

Engineering controls reduce employees’ exposures by removing the hazard from the process 
Health Hazard Evaluation Report 2016-0012-3302 Page 33

or by placing a barrier between the hazard and the employee. Engineering controls protect 

employees effectively without placing primary responsibility of implementation on the 

employee. 

1. Work with a ventilation engineer to ensure the production area is maintained under 

negative pressure compared with non-production spaces.

a. Keep all doors between the production and non-production areas closed at all 

times. The air-handling units serving the non-production areas might need to be 

re-balanced to maintain the non-production areas under positive pressure. This 

will prevent contaminant migration from the production area.

b. Ideally, the quality control laboratory should be maintained under negative 

pressure compared with the non-production areas but under positive pressure 

compared with the production area. This is applicable when the existing exhaust 

fan over the sample roasters is on or off.

2. Consider options for isolating the grinder to reduce overall alpha-diketone exposures 

in the production area. Moving the grinder closer to an exterior wall could make it 

easier to enclose the grinding process and reduce costs associated with ventilating 

the process separately. Other process areas such as blending and off-gassing might be 

candidates for enclosure with separate ventilation to further reduce concentrations of 

alpha-diketones in the production area.

3. Install local exhaust ventilation at point sources releasing the highest concentrations 

of alpha-diketones. Areas for consideration include at the main grinder, at the opening 

of supersacks, on the can line in packaging, and at the espresso machine in the quality 

control laboratory. In some cases, moving processes or equipment can make using 

local exhaust ventilation easier and more cost effective. A ventilation engineer can help 

with these decisions and verify the effectiveness of controls after implementation. 

Administrative Controls

Administrative controls are employer-dictated work practices and policies implemented 

to reduce or prevent hazardous exposures. Their effectiveness depends on employer 

commitment and employee acceptance. Regular monitoring and reinforcement are necessary 

to ensure policies and procedures are followed consistently.

1. Limit the amount of time non-production employees spend in the production area to 

the extent possible.

2. To reduce exposures to VOCs (including alpha-diketones), CO and CO2, minimize 

production tasks that require employees to place their heads near sources of roasted 

or ground coffee beans. Tying and untying supersacks presents the opportunity for 

short-term exposure to high concentrations of diacetyl and 2,3-pentanedione. Train 

employees on the proper technique for closure and opening of the supersacks.

3. After engineering controls have been installed, conduct personal air monitoring for 

diacetyl and 2,3-pentanedione on employees with primary duties in the production 
Page 34 Health Hazard Evaluation Report 2016-0012-3302

area. Because air levels of VOCs like diacetyl and 2,3-pentanedione can fluctuate from 

day to day based on production schedules, we recommend personal air sampling for 

diacetyl and 2,3-pentanedione over multiple days.

4. Consider conducting air sampling at the off-site warehouse where finished product is 

stored to determine if there are exposures above the NIOSH RELs.

5. Ensure employees understand potential hazards (e.g., diacetyl, 2,3-pentanedione, 

CO, CO2, green bean and roasted coffee dust) in the workplace and how to protect 

themselves. OSHA’s Hazard Communication Standard, also known as the “Right to 

Know Law” [29 CFR 1910.1200] requires that employees are informed and trained 

on potential work hazards and associated safe practices, procedures, and protective 

measures. Written information should be provided in the languages spoken by 

employees to ensure comprehension of the information.

6. Avoid the use of compressed air as much as possible during cleaning. Instead, use a 

vacuum system with a high-efficiency particle air filter and wet methods whenever 

possible. 

7. Ensure employees are educated to consider the risks of further exposure if they 

develop lower respiratory symptoms (e.g., cough, shortness of breath, wheezing) that 

are progressive and severe. Employees should report new, persistent, or worsening 

symptoms to their personal healthcare providers and to a designated individual at this 

workplace. Employees with new, persistent, or worsening symptoms should share this 

report with their healthcare providers.

Personal Protective Equipment

Personal protective equipment in the form of respiratory protection is considered the least 

effective means for controlling hazardous respiratory exposures because breakdowns in 

implementation can result in insufficient protection. Proper use of respiratory protection 

(respirators) requires a comprehensive respiratory protection program and a high level of 

employee and management involvement and commitment to assure that the right type of 

respirator is chosen for each hazard, respirators fit users and are maintained in good working 

order, and respirators are worn when they are needed. Supporting programs such as training, 

change-out schedules, and medical assessment might be necessary. Respirators should not be 

the sole method for controlling hazardous inhalation exposures. Rather, respirators should be 

used until effective engineering and administrative controls are in place. 

1. In addition to engineering and administrative controls, respiratory protection is a 

potential option to further reduce exposures to alpha-diketones (e.g., diacetyl and 

2,3-pentanedione). If follow-up air sampling after engineering controls have been 

installed indicates levels of diacetyl and 2,3-pentanedione above their respective 

NIOSH RELs and STELs, we recommend that respiratory protection be used during 

tasks with elevated exposures. Respirators used to reduce exposures to diacetyl 

and 2,3-pentanedione should be NIOSH-certified and equipped with organic vapor 

cartridges. The choice of respirator should be guided by personal exposure sampling 

for diacetyl and 2,3-pentanedione (NIOSH 2004). For reference, air-purifying half-
Health Hazard Evaluation Report 2016-0012-3302 Page 35

face respirators have an assigned protection factor (APF) of 10, and air-purifying 

full-face respirators have an APF of 50. Also, there are powered-air purifying 

respirators that have APFs of 25, 50, or 1000. A respirator’s APF refers to the maximal 

level of protectiveness a specific respirator design can achieve under laboratory 

conditions. The OSHA APFs can be found in Table 1 of OSHA Respiratory Protection 

Standard at https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_

table=STANDARDS&p_id=12716.

If respiratory protection is used, a written respiratory protection program should 

be implemented as required by the OSHA Respiratory Protection Standard (29 

CFR 1910.134), including training, fit testing, maintenance and use requirements.

2. Offer employees the voluntary use of N95 disposable filtering facepiece respirators 

when working with green coffee beans and chaff such as emptying burlap bags of 

green beans into the storage silos feed hopper, when cleaning the exhaust system 

of chaff, when emptying the chaff containers, or cleaning the green bean storage 

area. A written respiratory protection program is not required for voluntary use of 

N95 disposable filtering facepiece respirators. However, N95 respirators should 

be available in various sizes, and each potential N95 user should receive a copy of 

Appendix D of the OSHA Respiratory Protection Standard (http://www.osha.gov/pls/

oshaweb/owadisp.show_document?p_table=standards&p_id=9784). Information about 

Appendix D and voluntary use of respirators can be found on the OSHA website at 

https://www.osha.gov/video/respiratory_protection/voluntaryuse_transcript.html.

Please be aware that N95s are not protective against alpha-diketones (diacetyl, 

2,3-pentanedione, or 2,3-hexanedione). In cases of dual exposure to dust and 

alpha-diketones, NIOSH-certified organic vapor cartridges (for the alphadiketones) and particulate cartridges/filters (for the dust) would be warranted.

3. We did not formally assess noise during our visit. A noise survey would be necessary 

to determine the need for hearing protection and inclusion in a hearing conversation 

program. In the interim, continue to offer hearing protection for voluntary use. 

Medical Monitoring

The purpose of a medical monitoring program is to help assure the health of employees 

who have workplace exposures (e.g., diacetyl, 2,3-pentanedione, green coffee beans/dust) 

known to pose risk for potentially serious health conditions such as asthma or obliterative 

bronchiolitis. 

1. Institute a medical monitoring program for employees who work or assist in the 

production area and in the quality control laboratory. The medical monitoring should 

consist of evaluation with a questionnaire (to obtain health and work task information) 

and spirometry (to assess lung function) at baseline and at one year to monitor for 
Page 36 Health Hazard Evaluation Report 2016-0012-3302

respiratory symptoms and to establish employees’ baseline in lung function and 

any abnormal decline in lung function in the first year. Subsequently, an annual 

questionnaire evaluation should occur to monitor for respiratory symptoms. New 

or worsening respiratory symptoms should prompt additional evaluation including 

spirometry. Details about spirometry and a medical monitoring program can be found 

in chapter 9 of the NIOSH Criteria Document [NIOSH 2016].

2. If an employee is identified as likely having lung disease from exposure to diacetyl or 

2,3-pentanedione, it should be viewed as a sentinel event indicating that there was a 

breakdown in exposure controls and that there is potential risk for co-workers. Should 

this occur, the unanticipated source of exposure must be identified and brought under 

control. In addition, increased intensity of medical surveillance would be required for 

all employees performing similar job tasks or having similar or greater potential for 

exposure. The NIOSH Criteria Document provides detailed guidance on responses to 

such sentinel events [NIOSH 2016]. 

Smoking Cessation Program

In a workplace with risk of occupational lung disease, prevention of smoking-related lung 

disease is important and makes the detection of work-related adverse effects easier. We 

recommend implementing a smoking cessation program to assist employees to stop smoking. 

The Centers for Disease Control and Prevention offers tools and resources for setting up a 

smoking cessation program [CDC 2017].
Health Hazard Evaluation Report 2016-0012-3302 Page 37

Table A1. OSHA Methods 1013/1016 full-shift personal and area air sampling results by location, NIOSH 

industrial hygiene survey, April 2016

Analyte Sample 

Type Location N

Above

LOD

N (%)

Minimum

Concentration

(ppb)

Maximum

Concentration

(ppb)

Above

REL

N

Diacetyl Personal 2nd Floor Offices 5 5 (100%) 1.1 4.0 0

Diacetyl Personal Front Desk 2 2 (100%) 0.5 0.8 0

Diacetyl Personal Grinding 4 4 (100%) 10.3 13.8 4

Diacetyl Personal Packaging — 5LB Bag Line 4 4 (100%) 11.2 17.4 4

Diacetyl Personal Packaging — Can Line 20 20 (100%) 1.6 20.1 19

Diacetyl Personal Packaging — ICA Line 8 8 (100%) 11.0 21.5 8

Diacetyl Personal Packaging — Pillow Line 6 6 (100%) 6.0 25.6 6

Diacetyl Personal Production Area 7 7 (100%) 5.0 10.4 6

Diacetyl Personal Production Office 9 9 (100%) 1.4 8.1 3

Diacetyl Personal Quality Control Laboratory 12 12 (100%) 1.9 16.8 9

Diacetyl Personal Roasting 11 11 (100%) 4.4 19.2 10

Diacetyl Area Grinding 8 8 (100%) 12.0 68.9 N/A

Diacetyl Area 2nd Floor Sales Office 4 4 (100%) 1.3 2.6 N/A

Diacetyl Area 2nd Floor Library 4 4 (100%) 1.4 3.2 N/A

Diacetyl Area Kitchen 4 4 (100%) 0.5 3.0 N/A

Diacetyl Area Blending 4 4 (100%) 13.5 16.1 N/A

Diacetyl Area Packaging — 5LB Bag Line 4 4 (100%) 8.4 11.2 N/A

Diacetyl Area Packaging — Can Line 4 4 (100%) 5.9 11.5 N/A

Diacetyl Area Packaging — ICA Line 4 4 (100%) 9.6 19.6 N/A

Diacetyl Area Packaging — Pillow Line 4 4 (100%) 10.6 21.6 N/A

Diacetyl Area Off-gas 4 4 (100%) 9.1 12.4 N/A

Diacetyl Area Finished Product Racks 4 4 (100%) 9.1 13.5 N/A

Diacetyl Area Finished Products Storage 4 4 (100%) 8.2 11.4 N/A

Diacetyl Area Front Corner in Production 4 4 (100%) 4.6 8.2 N/A

Diacetyl Area Green Bean Storage 4 4 (100%) 8.0 12.3 N/A

Diacetyl Area Loading Docks 4 4 (100%) 1.3 7.1 N/A

Diacetyl Area Production Office 4 4 (100%) 6.8 9.1 N/A

Diacetyl Area Small Personal Grinders 4 4 (100%) 8.5 11.2 N/A

Diacetyl Area Staging Area 4 4 (100%) 8.3 10.6 N/A

Diacetyl Area Quality Control Laboratory 4 4 (100%) 7.7 11.7 N/A

Diacetyl Area Roasting 12 12 (100%) 7.5 37.8 N/A

Diacetyl Area Outside 4 0 (0%) < 0.3 < 0.3 N/A

2,3-Pentanedione Personal 2nd Floor Offices 5 5 (100%) 0.4 2.5 0

2,3-Pentanedione Personal Front Desk 2 1 (50%) < 0.3 0.5 0

2,3-Pentanedione Personal Grinding 4 4 (100%) 4.7 6.7 0

2,3-Pentanedione Personal Packaging — 5LB Bag Line 4 4 (100%) 5.0 9.3 0

2,3-Pentanedione Personal Packaging — Can Line 20 20 (100%) 4.6 9.6 1

2,3-Pentanedione Personal Packaging — ICA Line 8 8 (100%) 5.2 11.4 2

Appendix A: Tables
Page 38 Health Hazard Evaluation Report 2016-0012-3302

Analyte Sample 

Type Location N

Above

LOD

N (%)

Minimum

Concentration

(ppb)

Maximum

Concentration

(ppb)

Above

REL

N

2,3-Pentanedione Personal Packaging — Pillow Line 6 6 (100%) 3.4 15.8 1

2,3-Pentanedione Personal Production Area 7 7 (100%) 2.1 5.1 0

2,3-Pentanedione Personal Production Office 9 9 (100%) 0.6 5.1 0

2,3-Pentanedione Personal Quality Control Laboratory 12 12 (100%) 0.9 10.8 1

2,3-Pentanedione Personal Roasting 11 11 (100%) 2.7 10.2 2

2,3-Pentanedione Area Grinding 8 8 (100%) 5.2 31.4 N/A

2,3-Pentanedione Area 2nd Floor Sales Office 4 4 (100%) 0.7 1.3 N/A

2,3-Pentanedione Area 2nd Floor Library 4 3 (75%) < 0.2 1.5 N/A

2,3-Pentanedione Area Kitchen 4 4 (100%) 0.3 1.5 N/A

2,3-Pentanedione Area Blending 4 4 (100%) 6.3 8.3 N/A

2,3-Pentanedione Area Packaging — 5LB Line 4 4 (100%) 4.3 6.4 N/A

2,3-Pentanedione Area Packaging — Can Line 4 4 (100%) 2.3 6.3 N/A

2,3-Pentanedione Area Packaging — ICA Line 4 4 (100%) 4.8 10.2 N/A

2,3-Pentanedione Area Packaging — Pillow Line 4 4 (100%) 5.3 17.1 N/A

2,3-Pentanedione Area Off-gas 4 4 (100%) 4.6 7.3 N/A

2,3-Pentanedione Area Finished Product Racks 4 4 (100%) 4.4 7.7 N/A

2,3-Pentanedione Area Finished Products Storage 4 4 (100%) 4.3 6.9 N/A

2,3-Pentanedione Area Front Corner in Production 4 4 (100%) 2.4 3.7 N/A

2,3-Pentanedione Area Green Bean Storage 4 4 (100%) 4.2 7.1 N/A

2,3-Pentanedione Area Loading Docks 4 4 (100%) 1.1 2.7 N/A

2,3-Pentanedione Area Production Office 4 4 (100%) 3.3 5.1 N/A

2,3-Pentanedione Area Small Personal Grinders 4 4 (100%) 4.5 5.9 N/A

2,3-Pentanedione Area Staging Area 4 4 (100%) 3.9 4.5 N/A

2,3-Pentanedione Area Quality Control Laboratory 4 4 (100%) 3.6 7.6 N/A

2,3-Pentanedione Area Roasting 12 12 (100%) 3.7 23.0 N/A

2,3-Pentanedione Area Outside 4 0 (0%) <0.3 <0.3 N/A

2,3-Hexanedione Personal 2nd Floor Offices 5 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Personal Front Desk 2 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Personal Grinding 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Personal Packaging — 5LB Bag Line 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Personal Packaging — Can Line 20 1 (5%) < 0.1 0.4 —

2,3-Hexanedione Personal Packaging — ICA Line 8 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Personal Packaging — Pillow Line 6 0 (0%) < 0.1 < 0.6 —

2,3-Hexanedione Personal Production Area 7 1 (14%) < 0.2 0.3 —

2,3-Hexanedione Personal Production Office 9 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Personal Quality Control Laboratory 12 0 (0%) < 0.2 < 0.6 —

2,3-Hexanedione Personal Roasting 11 1 (9%) < 0.2 0.4 —

2,3-Hexanedione Area Grinding 8 2 (25%) < 0.2 1.4 —

2,3-Hexanedione Area 2nd Floor Sales Office 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area 2nd Floor Library 4 0 (0%) < 0.2 < 0.5 —

Table A1 (cont). OSHA Methods 1013/1016 full-shift personal and area air sampling results by location, 

NIOSH industrial hygiene survey, April 2016
Health Hazard Evaluation Report 2016-0012-3302 Page 39

Analyte Sample 

Type Location N

Above

LOD

N (%)

Minimum

Concentration

(ppb)

Maximum

Concentration

(ppb)

Above

REL

N

2,3-Hexanedione Area Kitchen 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Blending 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Packaging — 5LB Line 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Packaging — Can Line 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Packaging — ICA Line 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Packaging — Pillow Line 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Off-gas 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Finished Product Racks 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Finished Products Storage 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Front Corner in Production 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Green Bean Storage 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Loading Docks 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Production Office 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Small Personal Grinders 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Staging Area 4 1 (25%) < 0.2 0.8 —

2,3-Hexanedione Area Quality Control Laboratory 4 0 (0%) < 0.2 < 0.5 —

2,3-Hexanedione Area Roasting 12 1 (8%) <0.2 0.8 —

2,3-Hexanedione Area Outside 4 0 (0%) < 0.2 < 0.5 —

Note: NIOSH=National Institute for Occupational Safety and Health; OSHA=Occupational Safety and Health 

Administration; N=number of samples; Above LOD N (%)=number and percentage of samples above limit of detection 

(LOD); < indicates below the limit of detection; Above REL N=number of samples above the NIOSH recommended exposure 

limit (REL); ppb=parts per billion; N/A indicates that NIOSH RELs are specified for personal air samples, and cannot be 

directly applied to area air samples; “–“ indicates that there is currently no REL for 2,3-hexanedione. 

Table A1 (cont). OSHA Methods 1013/1016 full-shift personal and area air sampling results by location, 

NIOSH industrial hygiene survey, April 2016
Page 40 Health Hazard Evaluation Report 2016-0012-3302 Table A2. OSHA Methods 1013/1016 task-based personal air sampling results, NIOSH industrial hygiene survey, April 2016 Mean (minutes) Sample Duration (range) Maximum Concentration (ppb) Minimum Concentration (ppb) Above LOD N (%) N askT Analyte Diacetyl Cleaning packaging machine 1 1 (100%) 4.7 4.7 15 Diacetyl Grind coffee beans 10 10 (100%) 15.5 52.6 15 (14–16) Diacetyl Machine maintenance 5 4 (80%) < 1.1 15.4 15 (13–15) Diacetyl Move roasted beans or ground coffee 4 4 (100%) 4.5 56.9 7 (3–15) Diacetyl Package coffee 39 36 (92%) < 0.9 42.2 15 (12–16) Diacetyl Quality control laboratory 25 25 (100%) 2.1 20.4 11 (4–16) Diacetyl Rework packaging 4 4 (100%) 11.9 69.9 15 Diacetyl Roast coffee beans 19 19 (100%) 1.7 32.8 15 (13–21) Diacetyl Work with green beans 1 1 (100%) 4.8 4.8 24 2,3-Pentanedione Cleaning packaging machine 1 1 (100%) 2.2 2.2 15 2,3-Pentanedione Grind coffee beans 10 10 (100%) 6.2 24.3 15 (14–16) 2,3-Pentanedione Machine maintenance 5 4 (80%) < 1.1 7.8 15 (13–15) 2,3-Pentanedione Move roasted beans or ground coffee 4 4 (100%) 2.0 24.4 7 (3–15) 2,3-Pentanedione Package coffee 39 37 (95%) < 0.9 19.1 15 (12–16) 2,3-Pentanedione Quality control laboratory 25 25 (100%) 1.7 15.4 11 (4–16) 2,3-Pentanedione Rework packaging 4 4 (100%) 8.7 39.2 15 2,3-Pentanedione Roast coffee beans 19 19 (100%) 1.0 12.1 15 (13–21) 2,3-Pentanedione Work with green beans 1 1 (100%) 2.6 2.6 24 2,3-Hexanedione Cleaning packaging machine 1 0 (0%) < 1.4 < 1.4 15 2,3-Hexanedione Grind coffee beans 10 1 (10%) < 0.6 1.8 15 (14–16) 2,3-Hexanedione Machine maintenance 5 0 (0%) < 1.4 < 1.7 15 (13–15) 2,3-Hexanedione Move roasted beans or ground coffee 4 0 (0%) < 1.4 < 7.0 7 (3–15) 2,3-Hexanedione Package coffee 39 0 (0%) < 0.6 < 1.8 15 (12–16) 2,3-Hexanedione Quality control laboratory 25 0 (0%) < 0.7 < 5.4 11 (4–16) 2,3-Hexanedione Rework packaging 4 3 (75%) < 0.8 1.7 15 2,3-Hexanedione Roast coffee beans 19 0 (0%) < 0.5 < 1.6 15 (13–21) 2,3-Hexanedione Work with green beans 1 0 (0%) < 0.5 < 0.5 24 Note: OSHA=Occupational Safety and Health Administration; NIOSH=National Institute for Occupational Safety and Health; N=number of 

samples; Above LOD N (%)=number and percentage of samples above the limit of detection (LOD); ppb=parts per billion; < indicates below the limit of detection.
Health Hazard Evaluation Report 2016-0012-3302 Page 41

Table A3. Instantaneous* evacuated canister task-based air sampling concentration results, NIOSH 

survey, April 2016

Task Location Task Description Analyte (parts per billion)

Diacetyl 2,3-Pentanedione 2,3-Hexanedione

Blending

Dumping whole French Roast 

coffee beans into hopper along 

blending line

2,146.3 742.6 105.9

Grinding Sealing supersack after beans were 

ground 1,279.2 407.7 18.7

Removing ground coffee supersack 

from grinder 2,692.3 948.8 37.0

Removing ground coffee supersack 

from grinder 368.7 162.7 7.5

Packaging – Pillow Pack Loading ground coffee into hopper 3,765.2 3,377.3 95.7

Packaging – ICA Rework 12oz. packages 27.6 14.6 1.1

Quality Control Laboratory Cupping – smelling coffee 9.9 7.3 1.5

Cupping – smelling coffee 23.5 14.6 6.0

Cupping – stirring coffee (aroma 

evaluation) 19.4 11.1 2.1

Cupping – tasting coffee 9.4 6.8 < 0.9

Cupping – tasting coffee 21.3 11.8 4.4

Cupping – tasting coffee (start) 18.0 9.4 2.2

Cupping – tasting coffee (end) 14.5 7.4 1.3

Grinding coffee beans for espresso 40.5 19.8 1.8

Grinding coffee beans for espresso 26.5 12.0 1.3

Grinding coffee for cupping 15.8 14.4 < 0.9

Grinding coffee in sample grinder 26.9 16.4 2.7

Grinding coffee in sample grinder 29.4 20.8 2.0

Grinding coffee samples for 

production cupping 74.0 43.6 5.8

Pulling shots of espresso (brewing/

extracting) 24.5 11.0 2.8

Pulling shots of espresso (brewing/

extracting) 25.6 16.9 6.1

Roasting coffee beans in sample 

roaster 25.0 11.2 1.9

Weigh roasted beans 3.7 2.5 1.1

Roasting – Grinders Grinding quality control sample 34.7 16.0 < 0.9

Grinding quality control sample 74.9 53.2 1.9

Grinding quality control sample 97.7 100.8 70.6

Grinding quality control sample 18.2 10.3 1.3

Grinding quality control sample 49.3 34.5 1.7
Page 42 Health Hazard Evaluation Report 2016-0012-3302

Task Location Task Description Analyte (parts per billion)

Diacetyl 2,3-Pentanedione 2,3-Hexanedione

Roasting – Orange Roaster Collect sample of roasted beans 

from destoner 8.0 5.8 < 1.1

Collect sample of roasted beans 

from destoner 6.1 3.0 < 1.1

Pulling out ‘Tryer’ to smell and 

profile roast 14.3 8.1 1.6

Roasting – Red Roaster Pulling out ‘Tryer’ to smell and 

profile roast 4.2 2.3 < 1.4

Pulling out ‘Tryer’ to smell and 

profile roast 6.5 3.5 < 1.3

Pulling out ‘Tryer’ to smell and 

profile roast 19.1 7.6 < 1.3

Pulling out ‘Tryer’ to smell and 

profile roast 8.0 3.8 < 2.1

Pulling out ‘Tryer’ to smell and 

profile roast 0.9 0.6 0.2

Note: NIOSH=National Institute for Occupational Safety and Health; < indicates below the limit of detection.

*Sampling duration approximately 30 seconds; task-based air samples were collected by placing the inlet of the canister 

sampler in the employee’s personal breathing zone as he/she performed work task to mimic exposure.

Table A3 (cont). Instantaneous* evacuated canister task-based air sampling concentration results, 

NIOSH survey, April 2016
Health Hazard Evaluation Report 2016-0012-3302 Page 43

Table A4. Instantaneous* evacuated canister source air sampling results by location, NIOSH industrial 

hygiene survey, April 2016

Location Source Description Analyte (parts per billion)

Diacetyl 2,3-Pentanedione 2,3-Hexanedione

Blending Blender station 4 at tote discharge; conveyor 

not running 142.8 76.2 18.8

Grinding Grinding supersack of Breakfast Blend 11,160.1 2,738.7 272.1

Grinding supersack of Breakfast Blend 4,130.8 1,130.9 90.9

Main grinder transfer point into supersack 15.4 7.8 < 0.9

Transfer point of grinder into supersack. 

Origin: El Salvador; Full City roast 1,045.7 543.2 34.6

Transfer point of grinder into supersack. 

Origin: El Salvador; Full City roast 271.2 147.9 9.5

Transfer point of grinder into supersack 4,355.3 2,353.6 85.7

Transfer point of grinder into supersack 70.9 30.2 1.1

Off-Gas Opening of supersack; roasted at 10:00; 

ground at 11:00 10,541.0 4,122.8 204.6

Packaging 5LB bag line — outside enclosure where bag 

is filled 27.8 10.4 1.3

5LB bag line — where 2 bags are packed into 

cardboard box 29.6 10.7 0.9

5LB bag line — at front of auto-sealer 

outside of glass door 16.3 5.6 1.2

Can line — transfer point of transport hopper 

to feed hopper 19.3 9.3 < 0.9

Can line — point where beans enter can; 

French Roast blend 2,086.5 823.2 82.5

Can line — at top of hopper where supersack 

is emptied 55.1 21.1 2.8

Can line — transfer point of beans into can 

line via All-Fill hopper 124.6 66.0 4.2

Can line — transfer point of beans into can 

line via All-Fill hopper 113.7 60.0 4.3

Hand packing at All-Fill station; ground dark 

roast blend 170.3 50.7 4.1
Page 44 Health Hazard Evaluation Report 2016-0012-3302

Location Source Description Analyte (parts per billion)

Diacetyl 2,3-Pentanedione 2,3-Hexanedione

ICA line — supersack of freshly ground 

coffee from Mexico; medium & Vienna roast 26,406.1 13,138.5 377.6

ICA line — inside open door below hopper 

during repair 20.1 7.6 1.3

Production 

Area

Small personal grinders — grinding Uganda 

Med Blend 112.6 104.0 3.4

Small personal grinders — grinding Uganda 

Med Blend 11.5 5.0 < 0.9

Quality Control 

Laboratory Cupping — at cup at beginning of tasting 15.9 7.7 2.7

Cupping — at cup at end of tasting 19.4 9.6 < 0.9

Cupping — stirring coffee 30.2 19.8 1.8

Espresso — pulling espresso shots 467.3 430.4 17.1

Espresso grinder 809.3 679.3 27.4

Grinding — at sample grinder 142.1 73.8 9.3

Grinding — at sample grinder 249.7 208.0 9.4

Roasting Orange roaster destoner — Breakfast Blend 12.0 3.9 < 0.9

Orange roaster destoner — Breakfast Blend 63.5 18.0 1.2

Orange roaster destoner — Breakfast Blend 57.4 17.3 2.1

Orange roaster door to cooling tray — 

Breakfast Blend 11.8 3.9 < 0.9

Orange roaster door to cooling tray — 

Breakfast Blend 16.7 8.0 < 0.9

Orange roaster transfer point of cooling tray 

to destoner 4.5 2.3 < 0.9

Orange roaster transfer point of cooling tray 

to destoner 5.5 2.4 < 1.0

Orange roaster transfer point of cooling tray 

to destoner 12.6 11.7 11.5

Table A4 (cont). Instantaneous* evacuated canister source air sampling results by location, NIOSH 

industrial hygiene survey, April 2016
Health Hazard Evaluation Report 2016-0012-3302 Page 45

Location Source Description Analyte (parts per billion)

Diacetyl 2,3-Pentanedione 2,3-Hexanedione

Roasting Orange roaster cooling bin discharge to 

destoner 27.7 13.8 2.2

Red roaster door into cooling tray 10.9 3.2 < 1.2

Red roaster door into cooling tray — Vienna 

Med Roast 37.8 56.5 76.1

Red roaster cooling bin discharge to destoner 

— opening closed 30.4 12.7 1.4

Grinding sample of Breakfast Blend — top of 

bag at grinder discharge 2.2 0.9 < 0.6

Grinding sample of Breakfast Blend — top of 

bag at grinder discharge 67.6 51.2 1.7

Note: NIOSH=National Institute for Occupational Safety and Health; < indicates below the limit of detection for the 

instrument used to detect the analyte (i.e., diacetyl, 2,3-pentanedione, or 2,3-hexanedione%). *Sampling duration 

approximately 30 seconds; source-based air samples were collected by placing the inlet of the canister sampler close to 

a source.

Table A5. Instantaneous* evacuated canister pre-and post-shift background air sampling results, 

NIOSH industrial hygiene survey, April 2016

Tuesday 04/20/2016 Thursday 04/22/2016

Concentration (parts per billion)

Location Analyte AM PM AM PM 

Middle of Production Area Diacetyl 11.8 25.5 5.9 20.3

2,3-Pentanedione 4.2 8.4 2.0 7.3

2,3-Hexanedione 1.2 1.4 < 1.2 1.1

Between Staging Area & Diacetyl 9.9 38.2 5.6 19.3

Green Bean Storage 2,3-Pentanedione 3.5 20.1 2.6 8.6

2,3-Hexanedione 1.2 1.3 1.1 1.7

Note: NIOSH=National Institute for Occupational Safety and Health; < indicates result was below the limit of 

detection.

*Sampling duration approximately 30 seconds.

Table A4 (cont). Instantaneous* evacuated canister source air sampling results by location, NIOSH 

industrial hygiene survey, April 2016
Page 46 Health Hazard Evaluation Report 2016-0012-3302

Table A6. Bulk coffee sample results using headspace analysis, NIOSH industrial 

hygiene survey, April 2016

Bulk Sample Description Analyte (parts per billion)

Bean Type Origin Roast Diacetyl 2,3-Pentanedione 2,3-Hexanedione

Whole Peru Decaf Vienna 2124.7 1638.1 <

Ground Peru Decaf Vienna 402.4 389.3 <

Whole Honduran Dark Medium 1171.3 1462.8 <

Ground Honduran Dark Medium 871.4 1004.4 <

Whole Mexican Medium 865.6 927 271.7

Ground Mexican Medium 450.1 805 <

Whole Peru Decaf Full City 1806.4 2005.1 <

Ground Peru Decaf Full City 934.1 1096.9 <

Whole Honduran/Peru French 974.7 421.5 <

Ground Honduran/Peru French 314.0 105.8 300.8

Ground Mexican Medium & Vienna 704.4 681.5 222.8

Note: NIOSH=National Institute for Occupational Safety and Health; < indicates result was below the 

limit of detection.

Table A7. Real-time air monitoring for carbon dioxide, carbon monoxide, total volatile 

organic compound, temperature, relative humidity, NIOSH industrial hygiene survey, 

April 2016

Location CO2 ppm CO ppm TVOC ppm Temp °F RH %

Off-gas Area 610 1.4 735 67.6 37.8

Main Grinder: to right of 

discharge 596 7.7 — 69 34.7

Main Grinder: to left of discharge 749 25.7 3,270 69.3 22.4

Main Grinder: behind grinder 770 6.6 953 71.7 30.0 

Red Roaster 666 3.9 985 72.3 20.6

Roaster Sample Grinders 794 5.8 1,171 72.2 29.1

Can Line 553 7.8 1,251 73.3 36.9

ICA Line 576 6.2 1,207 72.5 38.2

Note: NIOSH=National Institute for Occupational Safety and Health; CO2=carbon dioxide; 

CO=carbon monoxide; TVOC=total volatile organic compound; ppm=parts per million; °F=degrees 

Fahrenheit; RH %=percent relative humidity; —=not measured
Health Hazard Evaluation Report 2016-0012-3302 Page 47 Table A8. Prevalence of reported symptoms, NIOSH medical survey, April 2016 s Experienced in the last 4 week N = 79 Number (%) Experienced in the last 12 months N = 79 Number (%) Symptom Nose symptoms* 57 (72%) 33 (42%) Eye symptoms† 43 (54%) 33 (42%) Sinusitis or sinus problems 25 (32%) 14 (18%) Problem with ability to smell 7 (9%) - Phlegm on most days for 3 months 10 (13%) - Lower respiratory symptoms (reported at least one of the following) 38 (48%) 18 (23%) Chest wheezing or whistling 18 (23%) 5 (6%) SOB on level ground or walking up a slight a hill 15 (19%) - Breathing trouble 18 (23%) 13 (17%) Awoke with chest tightness 10 (13%) 5 (6%) Awoke with shortness of breath 1 (1%) 1 (1%) Usual cough 8 (10%) 5 (6%) Asthma attack 4 (5%) 3 (4%) Systemic symptoms(reported at least one of the following) 39 (50%) 20 (25%) Flu-like achiness or achy joints 32 (41%) 13 (16%) Fever or chills 23 (29%) 3 (4%) Unusual tiredness or fatigue 12 (15%) 10 (13%) Note: N=number of participants; SOB=shortness of breath; “-“=no four week question was asked for the symptom. *Nose symptoms includes one or both of the following: 1) stuffy, itchy, or runny nose or 2) stinging, burning nose. †Eye symptoms includes one or both of the following: 1) watery, itchy eyes or 2) stinging, burning eyes.
Page 48 Health Hazard Evaluation Report 2016-0012-3302 Table A9. Prevalence of reported symptoms by time spent in production areas, NIOSH medical survey, April 2016 Spend any time in production areas Do not spend any time in production areas N = 32 Number (%) N = 47 Number (%) Symptom Nose symptoms* 35 (74%) 22 (69%) Eye symptoms† 24 (51%) 19 (59%) Sinusitis or sinus problems 14 (30%) 11 (34%) Problem with ability to smell 3 (6%) 4 (13%) Phlegm on most days for 3 months 6 (13%) 4 (13%) Lower respiratory symptoms (reported at least one of the following) 21 (45%) 17 (53%) Chest wheezing or whistling 8 (17%) 10 (31%) SOB on level ground or walking up a slight a hill 8 (17%) 7 (22%) Breathing trouble 10 (21%) 8 (25%) Awoke with chest tightness 7 (15%) 3 (9%) Awoke with shortness of breath 0 1 (3%) Usual cough 5 (11%) 3 (9%) Asthma attack 2 (4%) 2 (6%) Systemic symptoms(reported at least one of the following) 22 (47%) 17 (53%) Flu-like achiness or achy joints 17 (36%) 15 (47%) Fever or chills 13 (28%) 10 (31%) Unusual tiredness or fatigue 6 (13%) 6 (19%) Note: N=number of participants; SOB=shortness of breath *Nose symptoms includes one or both of the following: 1) stuffy, itchy, or runny nose or 2) stinging, burning nose. †Eye symptoms includes one or both of the following: 1) watery, itchy eyes or 2) stinging, burning eyes.
Health Hazard Evaluation Report 2016-0012-3302 Page 49 Table A10. Adjusted* comparisons of symptoms and self-reported physician diagnosis among NIOSH medical survey participants (N=79) to U.S. adult population, April 2016 ‡ SMR (95% CI) Expected Number Observed Number Comparative population† Health condition Watery, itchy eyes last 12 months NHANES III 39 30.7 1.3 (0.9–1.7) Stuffy, itchy, or runny nose last 12 months NHANES III 56 42.2 1.3 (1.0–1.7) Sinus problems last 12 months NHANES III 25 27.0 0.9 (0.6–1.4) Phlegm 3 consecutive month or more NHANES III 10 4.3 2.3 (1.3–4.3) Wheeze last 12 months NHANES 2007–2012 18 10.8 1.7 (1.0–2.6) Shortness of breath on exertion NHANES III 15 13.0 1.2 (0.7–1.9) Cough 3 consecutive months or more NHANES III 4 4.2 1.0 (0.4–2.4) Chronic bronchitis (physician-diagnosed) NHANES III 0 3.8 — Ever asthma (physician-diagnosed) NHANES 2007–2012 13 5.9 2.2 (1.3–3.8) Current asthma (physician-diagnosed) NHANES 2007–2012 10 3.9 2.6 (1.4–4.7) Note: NIOSH=National Institute for Occupational Safety and Health; NHANES=National Health and Nutrition Examination Survey; SMR=standardized morbidity ratio. *Adjusted for sex, race/ethnicity, age, and smoking categories. †We used the most recent NHANES survey available for each comparison. ‡95% confidence intervals (CIs) that exclude one are statistically significantly different from comparison with US adult population and are shown in bold
Page 50 Health Hazard Evaluation Report 2016-0012-3302

References

ACGIH (American Conference of Governmental Industrial Hygienist) [2017a]. 2017 

TLVs® and BEIs®: Threshold limit values for chemical substances and physical agents 

and biological exposure indices. Cincinnati, OH: American Conference of Governmental 

Industrial Hygienists. 

ACGIH [2017b]. Chemicals Substances and Other Issues Under Study (TLV®-CS). 

Available at: http://www.acgih.org/tlv-bei-guidelines/documentation-publications-and-data/

under-study-list/chemical-substances-and-other-issues-under-study-tlv. Date accessed: 

January 2018.

Akiyama M, Murakami K, Ohtani N, Iwatsuki K, Sotoyama K, Wada A, Tokuno K, Iwabuchi 

H, Tanaka K [2003]. Analysis of volatile compounds released during the grinding of roasted 

coffee beans using solid-phase microextraction. J Agric Food Chem 51(7):1961-1969.

Akpinar-Elci M, Travis WD, Lynch DA, Kreiss K [2004]. Bronchiolitis obliterans syndrome 

in popcorn production plant workers. Eur Respir J 24(2):298-302.

Anderson BA, Shimoni E, Liardon R, Labuza P [2003]. The diffusion kinetics of carbon 

dioxide in fresh roasted and ground coffee. J Food Eng 59:71-78.

Bailey RL, Cox-Ganser JM, Duling MG, LeBouf RF, Martin SB Jr, Bledsoe TA, Green 

BJ, Kreiss K [2015]. Respiratory morbidity in a coffee processing workplace with sentinel 

obliterative bronchiolitis cases. Am J Ind Med 58(12):1235-1245.

Berger KI, Reibman J, Oppenheimer BW, Vlahos I, Harrison D, Goldring RM [2013]. 

Lessons from the World Trade Center disaster: airway disease presenting as restrictive 

dysfunction. Chest 144(1):249-257. 

Burney PGJ and Chinn S [1987]. Developing a new questionnaire for measuring the 

prevalence and distribution of asthma. Chest 91(6 Suppl):79S-83S.

Burney PG, Laitinen LA, Perdrizet S, Huckauf H, Tattersfield AE, Chinn S, Poisson N, 

Heeren A, Britton JR, Jones T [1989]. Validity and repeatability of the IUATLD (1984) 

Bronchial symptoms questionnaire: an international comparison. Eur Respir J 2(10):940-945.

Burney PGJ, Luczynska C, Chinn S, Jarvis D [1994]. The European community respiratory 

health survey. Eur Respir J 7(5):954-960.

CDC (Centers for Disease Control and Prevention) [1996]. Third National Health and 

Nutrition Examination Survey, 1988–1994, NHANES III Examination Data File [CDROM]. 

Hyattsville, Maryland: U.S. Department of Health and Human Services, Centers for Disease 

Control and Prevention. (Public use data file documentation No. 76300.)
Health Hazard Evaluation Report 2016-0012-3302 Page 51

CDC [2013]. Obliterative bronchiolitis in workers in a coffee-processing facility—Texas, 

2008–2012. Morb Mortal Wkly Rep 62(16):305–307.

CDC [2017]. Smoking & tobacco use: quit smoking. Available at: https://www.cdc.gov/

tobacco/quit_smoking/index.htm. Date accessed: January 2018.

CDC [2018]. National Center for Health Statistics. National Health and Nutrition 

Examination Survey Data. Hyattsville, MD: U.S. Department of Health and Human Services, 

Centers for Disease Control and Prevention, [2007-2012] Available at: https://wwwn.cdc.

gov/nchs/nhanes/default.aspx. Date accessed: January 2018.

CFR. Code of Federal Regulations. Washington, DC: U.S. Government Printing Office, 

Office of the Federal Register.

Daglia M, Papetti A, Aceti C, Sordelli B, Spini V, Gazzani G [2007]. Isolation and 

determination of α-dicarbonyl compounds by RP-HPLC-DAD in green and roasted coffee. J 

Agric and Food Chem 55(22):8877-8882.

Day G, LeBouf R, Grote A, Pendergrass S, Cummings K, Kreiss K, and Kullman G [2011]. 

Identification and measurement of diacetyl substitutes in dry bakery mix production. J Occ 

Env Hygiene 8(2):93-103.

de Assumpção MS, Gonçalves RM, Martins R, Bobbio TG, Schivinski CI [2016]. Reference 

equations for impulse oscillometry system parameters in healthy Brazilian children and 

adolescents. Respir Care 61(8):1090-1099.

Desiraju K, Agrawal A [2016]. Impulse oscillometry: The state-of-art for lung function 

testing. Lung India 33(4):410-416. 

Duling MG, LeBouf RF, Cox-Ganser JM, Kreiss K, Martin SB Jr, Bailey RL [2016]. 

Environmental characterization of a coffee processing workplace with obliterative 

bronchiolitis in former workers. J Occup Environ Hyg 13(10):770-781.

Dweik RA, Boggs PB, Erzurum SC, Irvin CG, Leigh MW, Lundberg JO, Olin AC, Plummer 

AL, Taylor DR; American Thoracic Society Committee on Interpretation of Exhaled Nitric 

Oxide Levels (FENO) for Clinical Applications [2011]. An official ATS clinical practice 

guideline: interpretation of exhaled nitric oxide levels (FENO) for clinical applications. Am J 

Respir Crit Care Med 184(5):602-615.

EAACI Task Force on Occupational Rhinitis, Moscato G, Vandenplas O, Gerth Van Wijk R, 

Malo JL, Quirce S, Walusiak J, Castano R, De Groot H, Folletti I, Gautrin D, Yacoub MR, 

Perfetti L, Siracusa A [2008]. Occupational rhinitis. Allergy 63(8):969-980.
Page 52 Health Hazard Evaluation Report 2016-0012-3302

ECRHS (European Community Respiratory Health Survey)[2014]. Questionnaires, protocols 

and instructions. Available at: http://www.ecrhs.org/Quests.htm. Date accessed: January 

2018.

Ferris BG [1978]. Epidemiology standardization project. Am Rev Respir Dis 

118(Suppl):1–53.

Figley KD, Rawling FF [1950] Castor bean: an industrial hazard as a contaminant of green 

coffee dust and used burlap bags. J Allergy 21:545–553.

Grassi M, Rezzani C, Biino G, Marinoni A [2003]. Asthma-like symptoms assessment 

through ECRHS screening questionnaire scoring. J Clin Epidemiol 56(3):238–247.

Hankinson JL, Odencrantz JR, Fedan KB [1999]. Spirometric reference values from a sample 

of the general U.S. population. Am J Respir Crit Care Med 159(1):179-187.

Henneberger PK, Redlich CA, Callahan DB, Harber P, Lemière C, Martin J, Tarlo SM, 

Vandenplas O, Torén K; ATS Ad Hoc Committee on Work-Exacerbated Asthma [2011]. An 

official American Thoracic Society statement: work-exacerbated asthma. Am J Respir Crit 

Care Med 184(3):368–378.

Hubbs AF, Cumpston AM, Goldsmith WT, Battelli LA, Kashon ML, Jackson MC, Frazer 

DG, Fedan JS, Goravanahally MP, Castranova V, Kreiss K, Willard PA, Friend S, SchweglerBerry D, Fluharty KL, Sriram K [2012]. Respiratory and olfactory cytotoxicity of inhaled 

2,3-pentanedione in Sprague-Dawley rats. Am J Pathol 181(3):829-844.

Kanwal R, Kullman G, Piacitelli C, Boylstein R, Sahakian N, Martin S, Fedan K, Kreiss K 

[2006]. Evaluation of flavorings-related lung disease risk at six microwave popcorn plants.

J Occup Environ Med. 48(2):149-57.

Karr RM, Davies RJ, Butcher BT, Lehrer SB, Wilson MR, Dharmarajan V, Salvaggio JE 

[1978]. Occupational asthma. J Allergy Clin Immunol 61(1):54–65.

Kim TJ, Materna BL, Prudhomme JC, Fedan KB, Enright PL, Sahakian NM, Windham GC, 

Kreiss K [2010]. Industry-wide medical surveillance of California flavor manufacturing 

workers: Cross-sectional results. Am J Ind Med 53(9):857-865. 

King MS, Eisenberg R, Newman JH, Tolle JJ, Harrell FE Jr, Nian H, Ninan M, Lambright 

ES, Sheller JR, Johnson JE, Miller RF [2011]. Constrictive bronchiolitis in soldiers returning 

from Iraq and Afghanistan. N Engl J Med 365(3):222–230.

Komarow HD, Myles IA, Uzzaman A, Metcalfe DD [2011]. Impulse oscillometry in the 

evaluation of diseases of the airways in children. Ann Allergy Asthma Immunol 106(3):191-

199.
Health Hazard Evaluation Report 2016-0012-3302 Page 53

Kreiss K [2013]. Occupational causes of constrictive bronchiolitis. Curr Opin Allergy Clin 

Immunol 13(2):167-72.

Langford NJ [2005]. Carbon dioxide poisoning. Toxicol Rev 24(4):229-235.

LeBouf RF, Stefaniak AB, Virji, MA [2012]. Validation of evacuated canisters for sampling 

volatile organic compounds in healthcare settings. J Environ Monit 14(3):977–983.

LeBouf RF, Simmons M [2017]. Increased sensitivity of OSHA method analysis of diacetyl 

and 2,3-pentanedione in air. J Occup Environ Hyg 14(5):343-348.

Lee JY, Seo JH, Kim HY, Jung YH, Kwon JW, Kim BJ, Kim HB, Lee SY, Jang GC, Song DJ, 

Kim WK, Shim JY, Kim HJ, Shin YJ, Park JW, Cho SH, Lee JS, Hong SJ [2012]. Reference 

values of impulse oscillometry and its utility in the diagnosis of asthma in young Korean 

children. J Asthma 49(8):811-816. 

Lehrer SB, Karr RM, Salvaggio JE [1978]. Extraction and analysis of coffee bean allergens. 

Clin Allergy 8(3):217-226.

Malmberg LP, Pelkonen A, Poussa T, Pohianpalo A, Haahtela T, Turpeinen M [2002]. 

Determinants of respiratory system input impedance and bronchodilator response in healthy 

Finnish preschool children. Clin Physiol Funct Imaging 22(1):64-71.

Miller MR, Hankinson J, Brusasco V, Burgos F, Casaburi R, Coates A, Crapo R, Enright 

P, van der Grinten CP, Gustafsson P, Jensen R, Johnson DC, MacIntyre N, McKay R, 

Navajas D, Pedersen OF, Pellegrino R, Viegi G, Wanger J, ATS/ERS Task Force [2005]. 

Standardisation of spirometry. Eur Respir J 26(2):319-338.

Morgan DL, Jokinen MP, Price HC, Gwinn WM, Palmer SM, Flake GP [2012]. Bronchial 

and bronchiolar fibrosis in rats exposed to 2,3-pentanedione vapors: implications for 

bronchiolitis obliterans in humans. Toxicol Pathol 40(3):448-465.

Morgan DL, Jokinen MP, Johnson CL, Price HC, Gwinn WM, Bousquet RW, Flake GP 

[2016]. Chemical reactivity and respiratory toxicity of the α-diketone flavoring agents: 

2,3-butanedione, 2,3-pentanedione, and 2,3-hexanedione. Toxicol Pathol 44(5):763–783.

Newbury W, Crockett A, Newbury J [2008]. A pilot study to evaluate Australian predictive 

equations for the impulse oscillometry system. Respirology 13(7):1070-1075.

Newton J [2002]. Carbon monoxide exposure from coffee roasting. Appl Occup Environ Hyg

17(9):600-602.

NIOSH (National Institute for Occupational Safety and Health) [1998]. Occupational noise

exposure. DHHS (NIOSH) Publication Number 98-126. Available at: http://www.cdc.gov/

niosh/docs/98-126/. Date accessed: January 2018.
Page 54 Health Hazard Evaluation Report 2016-0012-3302

NIOSH [2003]. NIOSH manual of analytical methods (NMAM®). 4th ed. Schlecht PC, 

O’Connor PF, eds. Cincinnati, OH: U.S. Department of Health and Human Services, Centers 

for Disease Control and Prevention, National Institute for Occupational Safety and Health, 

DHHS (NIOSH) Publication 94–113 (August 1994); 1st Supplement Publication 96–135, 

2nd Supplement Publication 98–119; 3rd Supplement 2003–154. Available at: http://www.

cdc.gov/niosh/docs/2003-154/. Date accessed: January 2018.

NIOSH [2004]. NIOSH respirator selection logic. Cincinnati, OH: U.S. Department of 

Health and Human Services, Public Health Service, Centers for Disease Control, National 

Institute for Occupational Safety and Health, DHHS (NIOSH). Publication No. 2005-100. 

Available at: http://www.aresok.org/npg/nioshdbs/docs/2005-100/chapter2.html. Date 

accessed: January 2018.

NIOSH [2010]. NIOSH pocket guide to chemical hazards. Cincinnati, OH: U.S. Department 

of Health and Human Services, Centers for Disease Control and Prevention, National 

Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2010-168c. 

Available at: http://www.cdc.gov/niosh/npg/. Date accessed: January 2018.

NIOSH [2012]. Flavoring-related lung disease. Information for healthcare providers. 

Department of Health and Human Services, Centers for Disease Control and Prevention, 

DHHS (NIOSH) Publication No. 2012-148 (supersedes 2012-107). Available at: http://www.

cdc.gov/niosh/docs/2012-148/. Date accessed: January 2018

NIOSH [2016]. Flavorings-related lung disease: coffee processing facilities. Available at: 

http://www.cdc.gov/niosh/topics/flavorings/processing.html. Date assessed: January 2018.

Nishimura F, Abe S, Fukunaga T [2003]. Carbon monoxide poisoning from industrial coffee 

extraction. JAMA 290(3):334.

Oldenburg M, Bittner C, Baur X [2009]. Health risks due to coffee dust. Chest 136(2):536-

-544.

Oppenheimer BW, Goldring RM, Herberg ME, Hofer IS, Reyfman PA, Liautaud S, Rom 

WN, Reibman J, Berger KI [2007]. Distal airway function in symptomatic subjects with 

normal spirometry following World Trade Center dust exposure. Chest 132(4):1275–1282.

OSHA (Occupational Safety and Health Administration) [1993]. Compliance and 

Enforcement Activities Affected by the PELs Decision. August 5, 1993 Memorandum. 

Available at: https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_

table=INTERPRETATIONS&p_id=21220. Date accessed: January 2018.

OSHA [2003]. Enforcement Policy for Respiratory Hazards Not Covered by OSHA 

Permissible Exposure Limits. January 24, 2003 Memorandum. Available at: https://www.

osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_

id=24749. Date accessed: January 2018.
Health Hazard Evaluation Report 2016-0012-3302 Page 55

OSHA [2008]. Sampling and analytical methods: Method 1013 – Acetoin and diacetyl. 

Available at: http://www.osha.gov/dts/sltc/methods/validated/1013/1013.html. Date accessed: 

January 2018.

OSHA [2010]. Sampling and analytical methods: Method 1016 – 2,3-pentanedione. Available 

at: http://www.osha.gov/dts/sltc/methods/validated/1016/1016.html. Date accessed: January 

2018.

OSHA [2014]. OSHA Fact sheet: Do you have work-related asthma? A guide for you and 

your doctor. Washington, D.C.: U.S. Department of Labor, Occupational Safety and Health 

Administration. Available at: https://www.osha.gov/Publications/OSHA3707.pdf. Date 

accessed: January 2018.

OSHA [2017]. Permissible exposure limits – annotated tables. Available at: https://www.

osha.gov/dsg/annotated-pels/index.html. Date assessed: January 2018.

Park JH, Yoon JW, Shin YH, Jee HM, Wee YS, Chang SJ, Sim JH, Yum HY, Han MY [2011]. 

Reference values for respiratory system impedence using impulse oscillometry in healthy 

preschool children. Korean J Pediatr 54(2)64-68.

Pellegrino R, Viegi G, Brusasco V, Crapo RO, Burgos F, Casaburi R, Coates A, van der 

Grinten CP, Gustafsson P, Hankinson J, Jensen R, Johnson DC, MacIntyre N, McKay R, 

Miller MR, Navajas D, Pedersen OF, Wanger J [2005]. Interpretative strategies for lung 

function tests. Eur Respir J 26(5):948–968.

Raffel JB, Thompson J [2013]. Carbon monoxide from domestic coffee roasting: a case 

report. Ann Intern Med 159(11):795-796. 

Rondón C, Campo P, Galindo L, Blanca-López N, Cassinello MS, Rodriguez-Bada JL, Torres 

MJ, Blanca M [2012]. Prevalence and clinical relevance of local allergic rhinitis. Allergy. 

67(10):1282-1288.

Rondón C, Bogas G, Barrionuevo E, Blanca M, Torres MJ, Campo P [2017]. Nonallergic 

rhinitis and lower airway disease. Allergy 72(1):24-34.

Rose JJ, Wang L, Xu Q, McTiernan CF, Shiva S, Tejero J, Gladwin MT [2017]. Carbon 

monoxide poisoning: pathogenesis, management, and future directions of therapy. Am J 

Respir Crit Care Med 195(5):596-606.

Sahay S, Gera K, Bhargava SK, Shah A [2016]. Occurrence and impact of sinusitis in 

patients with asthma and/or allergic rhinitis. J Asthma 53(6):635-643. 

Sakwari G, Mamuya SH, Bråtveit M, Moen BE [2013]. Respiratory symptoms, exhaled nitric 

oxide, and lung function among workers in Tanzanian coffee factories. J Occup Environ Med

55(5):544-551.
Page 56 Health Hazard Evaluation Report 2016-0012-3302

Shaaban R, Zureik M, Soussan D, Neukirch C, Heinrich J, Sunyer J, Wjst M, Cerveri I, Pin 

I, Bousquet J, Jarvis D, Burney PG, Neukirch F, Leynaert B [2008]. Rhinitis and onset of 

asthma: a longitudinal population-based study. Lancet. 372(9643):1049-1057. 

Shi Y, Aledia AS, Tatavoosian AV, Vijayalakshmi S, Galant SP, George SC [2012]. Relating 

small airways to asthma control by using impulse oscillometry in children.

Allergy Clin Immunol 129(3):671-678. 

Schulz H, Flexeder C, Behr J, Heier M, Holle R, Huber RM, Jörres RA, Nowak D, Peters 

A, Wichmann HE, Heinrich J, Karrasch S; KORA Study Group [2013]. Reference values 

of impulse oscillometric lung function indices in adults of advanced age. PLoS One

8(5):e63366. doi: 10.1371/journal.pone.0063366. 

Schulze J, Biedebach S, Christmann M, Herrmann E, Voss S, Zielen S [2016]. Impulse 

oscillometry as a predictor of asthma exacerbations in young children. Respiration 91(2):107-

114. 

Smith HJ, Reinhold P, Goldman MD [2005]. Forced oscillation technique and impulse 

oscillometry. In: Gosselink R, Stam H, eds. European Respiratory Monograph 31: Lung 

Function Testing. Vol. 10. Wakefield, UK: European Respiratory Society Journals, pp. 72–

105.

Smith HJ (Hans-Juergen.Smith@CareFusion.com) [2015]. Questions about impulse 

oscillometry. Email of December 9, 2015, from Hans-Juergen Smith, CareFusion, to Rachel 

Bailey (feu2@cdc.gov), Respiratory Health Division, National Institute for Occupational 

Safety and Health, Centers for Disease Control and Prevention, Department of Health and 

Human Services. 

Song TW, Kim KW, Kim ES, Park JW, Sohn MH, Kim KE [2008]. Utility of impulse 

oscillometry in young children with asthma. Pediatr Allergy Immunol 19(8):763-768. 

Tarlo SM, Lemiere C [2014]. Occupational asthma. N Engl J Med 370:640-649.

Tarlo SM[2016]. Update on work-exacerbated asthma. Int J Occup Med Environ Health

29(3):369-374. 

Thomas KE, Trigg CJ, Baxter PJ, Topping M, Lacey J, Crook B, Whitehead P, Bennett JB, 

Davies RJ. [1991]. Factors relating to the development of respiratory symptoms in coffee 

process workers. Br J Ind Med 48(5):314–322.

Vogel J, Smidt U [1994] Impulse oscillometry. Analysis of lung mechanics in general 

practice and clinic, epidemiological and experimental research. 1st ed. Frankfurt: PMIVerlagsgruppe. 
Health Hazard Evaluation Report 2016-0012-3302 Page 57

Weinstein DJ, Hull JE, Ritchie BL, Hayes JA, Morris MJ [2016]. Exercise-associated 

excessive dynamic airway collapse in military personnel. Ann Am Thorac Soc 13(9):1476-

1482.

Zuskin E, Valić F, Skurić Z [1979]. Respiratory function in coffee workers. Br J Ind Med

36(2):117–122.

Zuskin E, Kanceljak B, Skurić Z, Butković D [1985]. Bronchial reactivity in green coffee 

exposure. Br J Ind Med 42(6):415-420.

Zuskin E, Schachter EN, Kanceljak B, Witek TJ Jr, Fein E [1993]. Organic dust disease of 

airways. Int Arch Occup Environ Health 65(2):135-140.
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Health Hazard Evaluation Report 2016-0012-3302 Page 59

Keywords: NAICS 311920 (Coffee roasting), Massachusetts, diacetyl, 2,3-pentanedione, 

2,3-hexanedione, coffee, carbon monoxide, carbon dioxide, volatile organic compounds 

(VOCs).
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The Health Hazard Evaluation Program investigates possible health hazards in the workplace 

under the authority of the Occupational Safety and Health Act of 1970 (29 U.S.C. § 669(a)

(6)). The Health Hazard Evaluation Program also provides, upon request, technical assistance 

to federal, state, and local agencies to investigate occupational health hazards and to prevent 

occupational disease or injury. Regulations guiding the Program can be found in Title 42, Code 

of Federal Regulations, Part 85; Requests for Health Hazard Evaluations (42 CPR Part 85).

Disclaimer 

The recommendations in this report are made on the basis of the findings at the workplace 

evaluated and may not be applicable to other workplaces.

Mention of any company or product in this report does not constitute endorsement by the 

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Citations to Web sites external to NIOSH do not constitute NIOSH endorsement of the 

sponsoring organizations or their programs or products. NIOSH is not responsible for the 

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Acknowledgments

Desktop Publisher: Tia McClelland 

Data Analysis Support: Nicole Edwards and Brian Tift

Laboratory Support: Dru Burns, Kyle Hatcher, Ryan LeBouf, Anand Ranpara

Site Visit Team Members: Marcia Stanton, Randall Nett, Randy Boylstein, Matthew Duling, 

Nicole Edwards, Kathleen Fedan, Jason Ham, Michael Humann, Robert Lawrence, Stephen 

Martin Jr., Chris Mugford, Alice Shumate, Brian Tift, and Sandy White

Availability of Report

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health department and the Occupational Safety and Health Administration Regional Office 

have also received a copy. This report is not copyrighted and may be freely reproduced.

This report is available at http://www.cdc.gov/niosh/hhe/reports/pdfs/2016-0012-3302.pdf.

All other Health Hazard Evaluation Reports may be found at http://www2a.cdc.gov/hhe/

search.asp.

Recommended citation for this report:

NIOSH [2018]. Health hazard evaluation report: Evaluation of exposures and 

respiratory health at a coffee roasting and packaging facility. By Stanton ML, Martin 

SB, Nett RJ. Morgantown, WV: U.S. Department of Health and Human Services, 

Centers for Disease Control and Prevention, National Institute for Occupational 

Safety and Health, NIOSH HHE Report No. 2016-0016-3302
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