NIOSH HEALTH HAZARD EVALUATION REPORT:

DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Disease Control and Prevention

National Institute for Occupational Safety and Health

HETA #98-0153-2883

Custom Products, Inc.

Mooresville, NC

November 2002

This Health Hazard Evaluation (HHE) report and any recommendations made herein are for the specific facility evaluated and may not be universally

applicable. Any recommendations made are not to be considered as final statements of NIOSH policy or of any agency or individual involved.

Additional HHE reports are available at http://www.cdc.gov/niosh/hhe/reports

This Health Hazard Evaluation (HHE) report and any recommendations made herein are for the specific facility evaluated and may not be universally

applicable. Any recommendations made are not to be considered as final statements of NIOSH policy or of any agency or individual involved.

Additional HHE reports are available at http://www.cdc.gov/niosh/hhe/reports

applicable. Any recommendations made are not to be considered as final statements of NIOSH policy or of any agency or individual involved.

Additional HHE reports are available at http://www.cdc.gov/niosh/hhe/reports
ii

PREFACE

The Hazard Evaluations and Technical Assistance Branch (HETAB) of the National Institute for

Occupational Safety and Health (NIOSH) conducts field investigations of possible health hazards in the

workplace. These investigations are conducted under the authority of Section 20(a)(6) of the Occupational

Safety and Health (OSHA) Act of 1970, 29 U.S.C. 669(a)(6) which authorizes the Secretary of Health and

Human Services, following a written request from any employer or authorized representative of employees,

to determine whether any substance normally found in the place of employment has potentially toxic effects

in such concentrations as used or found.

HETAB also provides, upon request, technical and consultative assistance to federal, state, and local agencies;

labor; industry; and other groups or individuals to control occupational health hazards and to prevent related

trauma and disease. Mention of company names or products does not constitute endorsement by NIOSH.

ACKNOWLEDGMENTS AND AVAILABILITY OF REPORT

This report was prepared by Dr. Christopher Reh, Mr. Vince Mortimer, Dr. Jeffrey Nemhauser, and Dr. Doug

Trout of HETAB, Division of Surveillance, Hazard Evaluations and Field Studies (DSHEFS). Field

assistance was provided by Mr. Kevin Dunn, Mr. Joshua Harney, MS, and Mr. Calvin Cook, MS. Analytical

support was provided by Datachem, Salt Lake City, UT. Desktop publishing was performed by Patricia

McGraw. Review and preparation for printing were performed by Penny Arthur.

Copies of this report have been sent to employee and management representatives at Custom Products and

the OSHA Regional Office. This report is not copyrighted and may be freely reproduced. Single copies of

this report will be available for a period of three years from the date of this report. To expedite your request,

include a self-addressed mailing label along with your written request to:

NIOSH Publications Office

4676 Columbia Parkway

Cincinnati, Ohio 45226

800-356-4674

After this time, copies may be purchased from the National Technical Information Service (NTIS) at

5825 Port Royal Road, Springfield, Virginia 22161. Information regarding the NTIS stock number may be

obtained from the NIOSH Publications Office at the Cincinnati address.

For the purpose of informing affected employees, copies of this report shall be

posted by the employer in a prominent place accessible to the employees for a period

of 30 calendar days.
iii

Highlights of the NIOSH Health Hazard Evaluation

Evaluation of Exposure to Spray Adhesive

 (1-bromopropane [1-BP])

This Health Hazard Evaluation was requested by the North Carolina Department of Labor to address concerns

about possible health problems related to working with a spray adhesive (that contains the chemical 1-

bromopropane [1-BP]).

What NIOSH Did

# We checked the air for 1-BP level.

# We checked the ventilation in the plant.

# We asked employees to fill out a

questionnaire and checked samples of blood

for blood counts.

# We made recommendations to improve

ventilation to decrease air levels of 1-BP.

# After the ventilation was improved by the

addition of spray booths, we rechecked the

air levels and the ventilation.

What NIOSH Found

# Before the ventilation was improved all

employees were exposed to high levels of

1-BP and the old ventilation was not

working well.

# Most of the blood counts were normal. The

few abnormal results we observed did not

appear to be related to 1-BP exposure.

# Some employees reported symptoms in the

questionnaire but none of the symptoms

could be related to 1-BP exposure.

# After spray booths were added in the

Covers and Assembly areas, air levels of 1-

BP were much lower.

# Some spray booth filters were clogged.

# Some employees were spraying cushions

outside the spray booths, which may be

adding to worker exposure to 1-BP.

What Custom Products Managers Can Do

# Inspect the spray booth filters regularly and

replace them when they are clogged.

# Train employees so that they use the spray

booths correctly and perform all spraying

inside the booths.

# Re-evaluate employee exposures to 1-BP

periodically to determine if further controls

are needed to decrease exposures to 1-BP.

What Custom Products Employees Can Do

# Attend all training and education sessions

given by the management.

# Follow instructions on proper us of the

adhesive spray equipment and spray booths.

Highlights of the HHE Report

What To Do For More Information:

We encourage you to read the full report. If you

would like a copy, either ask your health and

safety representative to make you a copy or call

1-513-841-4252 and ask for

 HETA Report #98-0153-2883

Health Hazard Evaluation Report 98-0153-2883
iv

Custom Products, Inc.

Mooresville, NC

November 2002

Christopher M. Reh, PhD, CIH

Vincent D. Mortimer, PE

Jeffrey B. Nemhauser, MD

Douglas Trout, MD, MHS

SUMMARY

On March 17, 1998, the National Institute for Occupational Safety and Health (NIOSH) received a request for a

health hazard evaluation (HHE) at Custom Products, Inc. in Mooresville, North Carolina. The request was

submitted by the North Carolina Department of Labor, and centered on workers' exposure to 1-bromopropane (1-

BP) during the spray application of solvent-based adhesives. In response to this request, NIOSH investigators

conducted two surveys at the facility. 

At the time of the first survey all employees at Custom Products (working in four departments: Saw, Assembly,

Sew, and Covers) were considered potentially exposed to 1-BP and 2-bromopropane (2-BP). 2-BP may be found

in most commercially available 1-BP formulations as a contaminant. The first survey consisted of exposure,

ventilation, and medical assessments. Personal breathing zone (PBZ) sampling for 1-BP was conducted in the

Assembly, Covers, and Saw departments, and area air sampling for 1-BP was performed in the Sew department.

Air velocity in and around the spray booths and unventilated tables was measured. Other aspects of the ventilation

assessment included evaluation of spray booth filter maintenance, and observation of air movement (using smoke

tubes), work tasks and movements of workers, and positioning of spray booth exhaust discharges. The medical

assessment included questionnaire administration for all employees in the Assembly, Cover, and Saw departments

and collection of blood samples and analysis of complete blood count (CBC). A CBC was drawn to determine if

1-BP exposure had any effect on workers’ ability to make blood cells. 

Sixty-nine full-shift, time-weighted average (TWA) 1-BP personal breathing zone (PBZ) exposure measurements

and 11 area air samples were collected during the first exposure assessment. The mean 1-BP full-shift PBZ

exposure concentration for participating workers was 168.9 parts per million (ppm), and the exposures ranged from

60.0 to 381.2 ppm. All of the exposures were above 25 ppm, a concentration that has been suggested as an

exposure guideline by several organizations. On average, the highest exposures were in the Covers department

(mean of 197.0 ppm), followed by the Assembly department (169.8 ppm), and the Saw department (117.1 ppm).

The mean area 1-BP air concentration in the Sew department was 128.1 ppm. Sprayers (working in the Covers and

Assembly departments) were exposed to a higher concentration of 1-BP than were other workers. The initial

ventilation assessment found that the Assembly department spray booths (there were no spray booths in the Covers

department) were inadequate. During the ventilation assessment, NIOSH investigators identified exhaust filters

that were either partially or completely clogged with spray adhesive, observed workers spraying some work pieces

outside the spray booths, and found that the spray booth exhaust discharge stacks were located in close proximity

to roof-top air intakes.
v

Forty-six (66%) of the 70 employees in the three departments completed the questionnaire and provided blood for

a CBC. The median cell counts, platelet counts, and hemoglobin concentrations were all within the normal ranges

provided by the laboratory. Several symptoms suggestive of excessive exposure to solvents were prevalent among

all workers surveyed; the prevalence of these symptoms was not statistically different between the higher-exposed

group compared to the lower-exposed group. Thirty-two (70%) of the 46 medical survey participants had PBZ air

sampling for 1-BP; for those 32 persons, additional statistical analyses were performed to examine the relationship

between individual exposures and the questionnaire and CBC results. The mean 1-BP concentration was not

statistically significantly greater among workers reporting symptoms compared to those not reporting symptoms.

There were no statistically significant relationships between the individual 1-BP exposure measures and the

corresponding CBC results. Several factors, including the fact that all participants in our survey were exposed to

1-BP, limited our ability to assess potential health effects.

Subsequent to the first site visit and the interim NIOSH report (May 26, 1999), Custom Products installed new

spray booths with local exhaust ventilation for all adhesive spraying operations (Assembly and Covers

departments). Follow-up exposure and ventilation surveys were conducted which included both PBZ and area air

sampling for 1-BP and 2-BP. 

The mean 1-BP PBZ exposure concentration at the follow-up survey was 19.0 ppm (range: 1.2 to 58.0 ppm), and

a total of 10 (43%) of the 23 1-BP PBZ exposure measurements exceeded 25 ppm. The mean 2-BP PBZ exposure

concentration was 0.14 ppm. The 1-BP PBZ air concentrations in the Sew department ranged from 1.1 to 1.9 ppm,

and no 2-BP was detected in any of the five samples collected in this department. The average velocity of air

flowing into the three spray booths measured during the follow-up ventilation assessment in the Assembly area was

approximately 100 ft/min, and the average velocity for the six booths in the Covers area was approximately 125

ft/min. Both of the values are below the recommended 150 ft/min; however, the hoods performed well based on

qualitative evaluation. Individual filter average velocities were higher for filter sections that were less clogged by

spray adhesive. For work performed inside the booths, air-flow visualization indicated that very little, if any,

contaminant would be recirculated into the worker’s breathing zone. We found that some pieces were being

sprayed outside the booths. 

The first NIOSH survey documented that all evaluated workers were exposed to 1-BP at concentrations above 25

ppm, and that the old spray booths in the Assembly department were ineffective in reducing workers’ 1-BP

exposures. Following the installation of new spray booths in the Covers and Assembly departments, the second

exposure assessment documented significantly reduced air concentrations of 1-BP, though some employees were

still exposed to concentrations of 1-BP above 25 ppm. Some of our ventilation measurements in the follow-up

assessment revealed less-than-recommended air velocity in the spray booths, which may have been due to filter

clogging by spray adhesive.

Analysis of the symptom and CBC data did not show meaningful relationships with 1-BP exposure levels;

however, given the limitations of our survey and lack of toxicologic data relevant to 1-BP in general, we are unable

to determine if worker exposure to 1-BP at Custom Products constitutes a health hazard. Considering this, and

while further data are being collected, NIOSH investigators believe that occupational exposure to 1-BP and 2-BP

should be minimized. Implementation of standard engineering, administrative, and work practice controls has been

effective in greatly reducing worker exposure to 1-BP. Recommendations are made in this report to further assist

in this goal, including recommendations concerning improved employee education and work practices. 
vi

KEYWORDS: SIC 2531 (Seats: Automobile, Vans, Aircraft, Railroad, and Other Public Conveyances) foam

fabrication, spray adhesives, 1-bromopropane, 2-bromopropane, n-propyl bromide, isopropyl bromide, engineering

controls, ventilation, spray booths, CBC, complete blood count, headache, reproductive abnormalities.
TABLE OF CONTENTS

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

Acknowledgments and Availability of Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv

Introduction ......................................................................... 1

Background ......................................................................... 1

Methods ........................................................................... 2

Exposure Assessments ............................................................. 2

Ventilation Assessments ............................................................ 3

Medical Assessments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Evaluation Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

1-BP and 2-BP Evaluation Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

First NIOSH Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Exposure Assessment ........................................................... 6

Ventilation Assessment .......................................................... 6

Medical Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

CBC Testing .............................................................. 7

Symptom/Medical History Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Second NIOSH Survey ............................................................. 8

Exposure Assessment ........................................................... 8

Ventilation Assessment .......................................................... 9

Discussion and Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Exposure Assessment .............................................................. 9

1-BP Exposure and Health Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

INTRODUCTION
Page 2 Health Hazard Evaluation Report No. 98-0153-2883

On March 17, 1998, the National Institute for

Occupational Safety and Health (NIOSH) received a

request for a health hazard evaluation (HHE) at

Custom Products, Inc. in Mooresville, North

Carolina. The request was submitted by the North

Carolina Department of Labor, and centered on

workers' exposure to 1-bromopropane (also known

as n-propyl bromide) during the spray application of

solvent-based adhesives. In response to this request,

NIOSH investigators conducted several site visits to

the facility. 

The first survey consisted of exposure, ventilation,

and medical assessments. On November 10–12,

1998, NIOSH industrial hygienists conducted a

1-bromopropane (1-BP) exposure assessment, and a

NIOSH engineer conducted a ventilation assessment

at the facility on November 23–24, 1998. NIOSH

medical officers conducted a medical assessment on

December 1-3, 1998. The findings from the

exposure and ventilation assessments were

summarized in an interim report (dated May 26,

1999) which included recommendations for spray

booths and local exhaust ventilation. The findings

from the medical assessment, and individual

notification of test results, were reported in

December 1999.

Subsequent to the May 26, 1999, interim report,

Custom Products installed spray booths with local

exhaust ventilation for all adhesive spraying

operations. Consequently, follow-up exposure and

ventilation surveys were conducted. The purpose of

the follow-up assessments was to document the

change in exposures and airflow patterns associated

with the installation of the new spray booths. The

NIOSH industrial hygienists conducted 1-BP and

2-bromopropane (2-BP [also known as isopropyl

bromide]) exposure assessments at Custom Products

on November 16, 2000. The results from that

exposure assessment were provided to Custom

Products on December 20, 2000. In addition, a final

ventilation assessment was conducted on April 19,

2001. This report summarizes all the previously

reported information and also the results from the

second ventilation survey.

BACKGROUND

Custom Products manufactures seat cushions for the

commercial aircraft industry. The cushions are foam

padded, and the foam is covered with NomexTM and

a decorative fabric. The cushions consist of several

pieces of cut foam glued together with a spray

adhesive. The cushion is inserted into the Nomex

cover, and the same spray adhesive is used to seal the

Nomex around the cushion. Finally, the fabric

exterior is applied to the cushion. The spray

adhesive used in these operations contains 1-BP as a

solvent vehicle. 

The production areas are divided into four

departments: Saw, Assembly, Sew, and Covers.

Bulk foam is cut with various saws in the Saw

department. In the Assembly department, the

adhesive is sprayed on the foam pieces, and the

pieces are pressed together (by hand) to form the

cushion. Thus, the workers in the Assembly

department are either sprayers or assemblers. The

Nomex covers are produced from bulk material in

the Sew department, and the covers are placed

around the cushions in the Covers department. All

production workers in the Covers department are

sprayers. All employees in these four departments

are potentially exposed to 1-BP and 2-BP. The

Assembly sprayers and assemblers, and Covers

workers work directly with the adhesive

formulations. Employees in the Saw and Sew

departments are indirectly exposed due to their

proximity to the spraying operations in the other

departments.

At the time of the first NIOSH survey, spray booths

for adhesive spraying operations were present in the

Assembly department. Custom Products had

fabricated these five spray booths using metal tubing

for a frame and clear plastic sheeting for the sides

and top of the enclosures. The booths were

approximately 76 inches high, 60 inches wide, and

54 inches deep. Each booth contained an

adjustable-height work surface, and was ventilated

though a duct opening in the back or side wall. The

air from the booths was exhausted directly to the

outside.
Health Hazard Evaluation Report No. 98-0153-2883 Page 3

After receiving the findings and recommendations

from the first exposure and ventilation assessment

(Appendix 1), Custom Products installed new spray

booths at all adhesive spraying stations in the

Assembly and Covers departments. The new booths

differed somewhat from the NIOSH recommended

design; the most significant design deviation was the

absence of baffles in the back of the booths. In the

Assembly department, the original five spray booths

were replaced with three angle-iron and sheet-metal

booths. These new booths were approximately 84

inches high, 60 inches wide, and 32 inches deep with

a plenum at the back. Each booth had a work surface

about 36 inches above the floor so that the open area

at the face of the booth was approximately 56 inches

by 48 inches. The ceiling of each booth extended 24

inches beyond the front edge of the work surface out

over where the worker stood while spraying adhesive

on foam cushion components inside each booth.

Six new booths had also been fabricated for the

Covers area. The design was similar to that

described above except that the booths were wider to

allow two workers to use a booth to spray adhesive

and insert finished cushions into covers. These

booths were approximately 84 inches high and 96

inches wide, with an open area of approximately 92

inches by 48 inches. One of these booths had a 32-

inch deep work surface, another was approximately

30 inches deep, and the depth of the other four was

approximately 26 inches.

In both areas, the top of each hood extended 24

inches beyond the work surface edge. The edges of

the side panels were angled to connect the front of

the work surface with the extended front edge of the

top surface of the hood. At the back of the hoods, the

air entered the plenum through 20-inch square filter

elements. Each filter was a grid of 16 open areas, 4-

1/4 inch square. The single-worker hoods in the

Assembly area had four filters; the wider hoods in the

Covers area had eight filters. The filters collected the

excess adhesive, preventing the stringy, “cottoncandy-like” strands from being drawn into the

exhaust system. 

At the time of the second NIOSH survey, two

different adhesives were used at Custom Products.

The Assembly department used Whisper Spray

(Imperial Adhesives, Cincinnati, Ohio), which

contains 60–70% by weight 1-BP. The adhesive

used in the Covers department was Fire Retardant

Soft Seam 6460 (Mid South Adhesives, Memphis,

Tennessee), which contains 60–80% by weight 1-BP.

A small percentage of 2-BP is usually present as a

contaminant in most 1-BP-containing formulations.

METHODS

Exposure Assessments

For the first NIOSH survey, all workers in the

Assembly, Covers, and Saw departments were asked

to participate in at least one shift of 1-BP inhalation

exposure measurement. Also, area air sampling for

1-BP was performed at randomly selected work

stations in the Sew department. During the second

survey, all employees in the Assembly, Covers, and

Saw departments were again targeted for a full-shift

1-BP and 2-BP inhalation exposure measurement.

Short-term (15-minute) 1-BP and 2-BP inhalation

exposure measurements were also collected from

sprayers in the Assembly and Covers departments.

In addition, area air sampling for 1-BP and 2-BP was

conducted at various locations and work stations in

the Sew Department. Employee participation in both

surveys was voluntary. For the employees'

inhalation exposure measurements, the sampling

pumps and sample trains were worn by the subjects,

and the sample media were placed in the subjects'

breathing zones (personal breathing zone [PBZ]

samples).

During both surveys, air sampling was conducted

using a NIOSH draft analytical method for 1-BP and

2-BP. In this method, air is drawn through a standard

charcoal tube (SKC Anasorb® CSC Lot 2000) at a

nominal flowrate of 50 to 100 milliliters per minute

(ml/min) using a calibrated personal sampling pump.

After sampling, the charcoal tubes were capped and

shipped refrigerated to the analytical laboratory. The
Page 4 Health Hazard Evaluation Report No. 98-0153-2883

front and back sections of the charcoal tubes were

placed in glass vials, and each section was desorbed

for 30 minutes with 1 ml of carbon disulfide. Each

sample was analyzed for both 1-BP and 2-BP using

gas chromatography with a flame ionization

detector.

The 1-BP limit of detection (LOD) and limit of

quantification (LOQ) for the draft NIOSH method

were 1 microgram per sample (:g/sample) and 4

:g/sample, respectively. The LOD and LOQ for

2-BP were 1.0 and 3 :g/sample, respectively. LODs

and LOQs are values determined by the analytical

procedure used to analyze the samples, and are not

dependent on sample volume. Minimum detectable

concentrations (MDCs) and minimum quantifiable

concentrations (MQCs) are determined by dividing

the LODs and LOQs by air sample volumes

appropriate for the given set of samples. For this

HHE site visit, the average sample volume for a

given set of samples was used to calculate these

values. MDCs and MQCs for all exposure data can

be found at the bottom of the appropriate data tables

and appendices. Summary data are presented in this

report; complete data for the two exposure

assessments are presented in Appendices 2 and 3.

Ventilation Assessments

Air velocity in and around the spray booths and

tables, where spraying and/or assembling operations

were performed, was measured with a hot-wire

anemometer (TSI VelociCalc Plus model 8386). 

The center-point velocity for each small filter grid

opening was measured, giving 64 readings for each

single-station hood and 128 readings for each doublestation hood. For computation, each 16-grid filter

was averaged separately to give 4 values for each

single-station hood, and 8 values for each doublestation hood. Additionally, air velocity 12-inches

above the work surface was measured at 6, 12, 18,

24, and 30 inches (if the work surface was deep

enough) from the back of the hood at the center and

1 foot in from each side panel. The center line was

measured twice and the readings were compared and

averaged to give one set of values for the line.

A rating of filter clogging was estimated by visual

inspection for each small filter opening. An 11-point

scale was used, with zero being no clogging and 10

being no-flow. Each 16-grid filter was averaged

separately, and the number was reported as a

percentage of openness.

The movement of air was observed using smoke

tubes, small glass tubes which release a thin trail of

chemical smoke showing the direction of air flow.

At the same time, the work tasks and movements of

the workers were noted. The flow of air under and

around the doors leading to the outdoors was also

observed using smoke tubes. The position of the

spray booth exhaust discharges relative to the

location of the air-handler outside air intakes on the

roof was noted, and the flow of air around these units

was observed using smoke tubes.

Medical Assessments

A questionnaire was offered to all employees in

departments in which PBZ sampling was occurring,

which included the Assembly, Covers, and Saw

departments (on both morning and evening shifts).

The questionnaire included questions concerning

basic demographic information and work and

medical history. Questions used to assess possible

effects of overexposure to solvents included

questions about headache, feeling “drunk,” abnormal

fatigue, and problems concentrating. Several

questions were asked in the questionnaire concerning

history of reproductive problems. All employees

filling out the questionnaire were asked to provide a

sample of blood, after providing informed consent,

for a complete blood count (CBC). The CBC was

performed on participants to evaluate whether

exposure to 1-BP can result im impaired production

of blood cells. Elements of the CBC used for the

purpose of this evaluation included the red blood

cell, platelet, and white blood cell counts and

hemoglobin concentration. Hemoglobin (the

oxygen-carrying protein of red blood cells)

concentration is a commonly used clinical measure

of the ability of blood to carry oxygen. 

Forty-six (66%) of the 70 employees in the three

participating departments (Assembly, Covers, and
Health Hazard Evaluation Report No. 98-0153-2883 Page 5

Saw) present at the time of the evaluation completed

the questionnaire and provided blood for a CBC.

Because all employees taking part in this HHE were

exposed to 1-BP, the relationship between exposure

to 1-BP and potential health effects was evaluated by

grouping workers into exposure groups based

primarily on job title (sprayers [in Assembly and

Covers departments], assembly workers [Assembly

department], and others [Saw department workers

and one supervisor from the Covers department]).

Exposure groups were created based on the industrial

hygiene sampling data for each job title at the time of

the first NIOSH exposure survey. For example, the

mean 1-BP concentration for sprayers was assigned

as the exposure for all sprayers.

Among the 46 participants, three had jobs for which

there was no quantitative information concerning

exposure to 1-BP. Those three were excluded from

this group analysis, leaving 43 participants with

exposure information available from the NIOSH

survey. Group exposure information was used to

determine whether workers in different exposure

groups had statistically significant differences in their

CBC endpoints or in questionnaire responses

concerning health problems. To compare the

distribution of CBC results (red blood cell, white

blood cell, platelet counts, and hemoglobin

concentration) between the sprayers and the nonsprayers (assembly workers and others), the median

was used as the measure of central tendency and the

Wilcoxon two-sample test was used to test for

statistical significance. The prevalence of symptoms

potentially related to excessive exposure to 1-BP was

calculated for each of the three exposure groups. The

magnitude of the relationship between sprayers and

non-sprayers was assessed by the prevalence ratio

(PR); a 95 percent confidence interval (95 % CI)

which excluded one was considered to indicate a

statistically significant finding. The PR represents

the prevalence of an outcome (for example, the

occurrence of headache) in the sprayers relative to

the prevalence in the non-sprayers. A PR of one

means there is no association between the outcome

and “greater exposure.” A PR of greater than

one indicates evidence of an association. For

example, a PR of two would mean that a sprayer may

be twice as likely to have reported the outcome than

a non-sprayer.

Thirty-two of the medical survey participants had

PBZ air sampling conducted for 1-BP. For those 32

persons, statistical analyses were performed to

examine the relationship between individual 1-BP

exposures and the questionnaire and CBC results

(even if the CBC results were within the normal

ranges provided by the laboratory). Linear

regression was used to assess the relationship

between the CBC elements and individual 1-BP

exposure measurements. Non–occupational factors

that were taken into account in the analyses of CBCs

included: age, gender, current cigarette smoking

status, and alcohol use. For symptoms reported in

the questionnaire, the mean 1-BP exposure

concentration among persons reporting a symptom

(compared to those not reporting the symptom) was

evaluated using a t-test to test for statistical

significance. Analyses were done using SAS

software (Version 8.2). A p-value of # .05 was used

to indicate statistical significance.

EVALUATION CRITERIA

As a guide to the evaluation of the hazards posed by

workplace exposures, NIOSH field staff employ

environmental evaluation criteria for the assessment

of a number of chemical and physical agents. These

criteria are intended to suggest levels of exposure to

which most workers may be exposed up to 10 hours

per day, 40 hours per week for a working lifetime

without experiencing adverse health effects. It is,

however, important to note that not all workers will

be protected from adverse health effects even though

their exposures are maintained below these levels. A

small percentage may experience adverse health

effects because of individual susceptibility, a preexisting medical condition, and/or a hypersensitivity

(allergy). In addition, some hazardous substances

may act in combination with other workplace

exposures, the general environment, or with

medications or personal habits of the worker to

produce health effects even if the occupational

exposures are controlled at the level set by the

criteria. These combined effects are often not
Page 6 Health Hazard Evaluation Report No. 98-0153-2883

considered in the evaluation criteria. Also, some

substances are absorbed by direct contact with the

skin and mucous membranes, and thus potentially

increases the overall exposure. Finally, evaluation

criteria may change over the years as new

information on the toxic effects of an agent become

available.

The primary sources of environmental evaluation

criteria for the workplace are: (1) NIOSH

Recommended Exposure Limits (RELs),1

 (2) the

American Conference of Governmental Industrial

Hygienists’ (ACGIH®) Threshold Limit Values

(TLVs®),2

 and (3) the U.S. Department of Labor,

Occupational Safety and Health Administration

(OSHA) Permissible Exposure Limits (PELs).3

Employers are encouraged to follow the OSHA

limits, the NIOSH RELs, the ACGIH TLVs, or

whichever are the more protective criterion.

OSHA requires an employer to furnish employees a

place of employment that is free from recognized

hazards that are causing or are likely to cause death

or serious physical harm [Occupational Safety and

Health Act of 1970, Public Law 91–596, sec.

5.(a)(1)]. Employers should understand that not all

hazardous chemicals have specific OSHA exposure

limits such as PELs and short-term exposure limits

(STELs). However, an employer is still required by

OSHA to protect their employees from hazards, even

in the absence of a specific OSHA PEL.

A time-weighted average (TWA) exposure refers to

the average airborne concentration of a substance

during a normal 8- to 10-hour workday. Some

substances have recommended STEL or ceiling

values which are intended to supplement the TWA

where there are recognized toxic effects from higher

exposures over the short-term.

1-BP and 2-BP Evaluation

Criteria

Little information was available concerning potential

health effects related to occupational exposure to 1-

BP at the time this HHE was initiated. A review of

the literature concerning 1-BP and 2-BP is presented

in Appendix 4. As with other solvents, occupational

exposure to 1-BP may occur via both inhalation and

skin absorption. Potential health effects related to

overexposure to 1-BP (and many other solvents) may

include irritation of the eyes, mucous membranes,

upper respiratory tract, and skin. At higher levels of

exposure, central nervous system depression

(characterized by headache and dizziness, and

possibly leading to loss of consciousness) may occur.

A few studies have addressed the issue of specific

health effects among workers occupationally

exposed to 2-BP. In a series of studies, 33 electronic

assembly workers working with 2-BP as the major

component in a cleaning solution were evaluated.1,2

Those evaluations suggested that occupational

exposure to 2-BP may have been associated with

damage to both male and female organs of

reproduction (ovarian failure and sperm

abnormalities) and also bone marrow failure

(pancytopenia [low blood counts]). Animal studies

have suggested that 2-BP may cause testicular and

bone marrow abnormalities in rats.3

 Because of the

concern that 1-BP may cause health effects similar to

those reported for 2-BP, this HHE primarily

addressed reproductive (by questionnaire) and

hematologic (by questionnaire and CBC) concerns in

our medical assessment. 

Currently, there are no NIOSH, ACGIH, or OSHA

exposure evaluation criteria for 1-BP. Albemarle

Corporation, a manufacturer of 1-BP, has developed

an occupational exposure limit for 1-BP which is

based on the initial, unaudited data from a two

generation reproductive study in rats.4

 Based on the

results of that study and a 10-fold safety factor,

Albemarle set their 1-BP recommended exposure

guideline at 25 ppm as an 8-hour TWA exposure.5

More recently, after a review of available exposure

data and human and animal toxicologic data, but

based primarily on data from animal studies

(including effects on the male reproductive system

[sperm motility]), the Environmental Protection

Agency (EPA) has proposed an Acceptable

Industrial Exposure Limit (AEL) for 1-BP of 25

ppm.6

 This AEL currently exists only in draft form

and may be subject to further revision following

public comment.
Health Hazard Evaluation Report No. 98-0153-2883 Page 7

The South Korean Ministry of Labor is the only

group that has developed an occupational exposure

guideline/limit for 2-BP. In 1998, the Ministry of

Labor issued an exposure standard for 2-BP of 1 ppm

as an 8-hour TWA.7

 This standard was based on a

limited number of workplace epidemiological studies

and toxicological (animal) studies which found that

2-BP exposure produces reproductive effects in both

males (low sperm count) and females (ovarian

dysfunction), and also affects the hematopoietic

system.8,9,10,11,12,13,14

RESULTS

First NIOSH Survey

Exposure Assessment

During the two-day period, a total of 138 half-shift,

TWA air samples were collected from workers in the

Assembly, Saw, and Covers departments. Air

sampling was conducted for one day on all workers

in the Saw and Covers departments, and for two days

on workers in the Assembly department. These

samples resulted in 69 full-shift, TWA 1-BP

exposure determinations for workers in these

departments. In addition, 11 area air samples were

collected from randomly selected work stations in the

Sew department.

The data from the 1-BP exposure determinations are

presented in Appendix 2, and summary results based

on these data are in Table 1. The mean 1-BP fullshift exposure concentration from all PBZ samples

was 168.9 ppm, and the exposures ranged from 60.0

to 381.2 ppm. All of the exposures were above 25

ppm, and only two exposures were less than 100

ppm. On average, the highest exposures were in the

Covers department (mean of 197.0 ppm), followed

by the Assembly department (169.8 ppm), and the

Saw department (117.1 ppm). The highest 1-BP

exposure was found in a Covers department worker

(381.2 ppm), and the two exposures that were below

100 ppm were found in a Saw operator (85.1 ppm)

and an Assembly department assembler (60.0 ppm).

A comparison of the exposures of sprayers in the

Covers department versus sprayers in the Assembly

department revealed no significant difference in 1-BP

concentrations between these two groups (p = 0.4).

1-BP exposures were higher among sprayers (in both

Covers and Assembly departments) compared to all

other workers (p < 0.0001), and exposures were

higher in Assembly department sprayers compared to

Assembly department assemblers (p=0.04). The data

from the area air sampling in the Sew department are

shown in Table 2. The mean area 1-BP air

concentration in this department was 128.1 ppm, and

the concentrations ranged from 107.3 to 160.9 ppm.

Ventilation Assessment

The measured exhaust flow rates for the five booths

were between 200 and 900 cubic feet of air per

minute (CFM). The lowest value was less than 250

CFM due to the filter for booth #2 being more than

half covered with the spray adhesive. When a new

filter was installed, the flow rate doubled. 

With an open area for each booth of about 32 square

feet, the average velocity over the face of each booth,

calculated from the exhaust flow rate, ranged from 13

to 25 ft/min. The average face velocity measured in

the top half of the booth was higher, ranging from 24

to 40 ft/min. The average face velocities and flow

rates are summarized in Table 3.

The general flow of air within the Assembly area was

from the northeast to the southwest, although in front

of booths 1 and 2, the flow was more towards the

northwest. In the Covers area, the general flow was

from south to north along the east wall of the

building where the work tables were located.

Specifically, in front of booth 1, air from in front of

the booth did flow around the left edge of the booth,

across the work table. In front of booth 2, air flowed

across the work table, around the right edge of the

booth, and across the front of the booth. For both

booths, smoke released from a smoke tube close to

the face of the booth entered the booth, but smoke

released a few feet from the face did not enter the

booth. The flow of air around booths 3 and 5 was

similar to booth 2, and the flow of air around booth

4 was similar to booth 1.
Page 8 Health Hazard Evaluation Report No. 98-0153-2883

Although the booths were adequately sized for the

work being performed, some pieces were sprayed

outside the booth. Some pieces were sprayed while

on the work table to add adhesive during the

assembly; others were sprayed in front of the booth,

possibly because the lighting was better or because

the piece had already been removed from the booth

and then a need for more adhesive was noticed. In

the Covers area, although the amount of spraying

was less than in the Assembly area, the workers got

just as close to the sprayed pieces while putting the

fabric covers over the foam.

The differential pressures inside the plant were all

negative with respect to outside the plant, so that air

came into the plant through all the outside doors.

The temperature inside the plant was approximately

75°F, and the relative humidity was approximately

50 %. 

On the roof, the spray booth exhaust discharge stacks

extended only 3-1/2 ft above the roof, and each was

capped with a weather-cap which obstructed and

deflected the vertical flow of air from the discharge

pipe. The discharge points for booths 1 and 2 and for

booth 5 were located only a few feet southwest of the

air intake of two of the roof-top air-conditioners.

The discharge point for booths 3 and 4 was located

approximately 10 feet southeast of the air intake of a

third roof-top air-conditioner. The height differences

between discharge and intake openings were only a

few feet.

Medical Assessment

Table 4 presents information describing the 43

survey participants. The majority of participants

were female, and the length of time working at their

current job varied for Assembly and Covers

employees (four years) compared to Saw employees

(nine years).

CBC Testing

The median red blood cell count was 4.3 million

cells per cubic millimeter (mm3

) (laboratory normal

range 3.8 - 5.8 million per mm3

), the median

hemoglobin concentration was 13.6 grams per

deciliter (g/dl) (laboratory normal range 11.6 - 17.1

g/dl), the median white blood cell count was 6,700

cells per mm3

 (laboratory normal range 3,900 -

11,400 per mm3

), and the median platelet count was

202,000 per mm3

 (laboratory normal range 140,000 -

400,00 per mm3

). Five of the CBC measurements

were outside the normal ranges. One person had a

white blood cell count of 3,700 per mm3

, one person

had a platelet count of 540,000 per mm3

, and three

had hemoglobin concentrations outside the normal

range. All three of these latter participants were in

the Covers department; two of the three had PBZ

measurements (these were 127 ppm and 265 ppm).

The rest of the CBC measurements were within the

normal ranges. None of the participants had

decreases of all three blood components. The

median values of the red blood cell counts and

hemoglobin concentrations of sprayers were less than

those values from non-sprayers, although the

differences were not statistically significant (Table

5). 

To evaluate a possible association between CBC test

results and 1-BP exposure, linear regression analyses

were performed between red blood cell, hemoglobin,

white blood cell, and platelet counts and 1-BP

exposure (as determined by PBZ 1-BP

concentrations). We found that hemoglobin and red

blood cell counts were correlated (r=0.63) and that

women participants were more likely to have both

lower red blood cell counts (and hemoglobin
Health Hazard Evaluation Report No. 98-0153-2883 Page 9

 concentrations) and greater exposure to 1-BP. There

were no statistically significant relationships between

the individual 1-BP exposure measures and the CBC

results, including white blood cells ($=0.008, p=0.3),

platelets ($=0.064, p=0.8), red blood cells ($= -

0,.008, p=0.6; controlling for gender), and

hemoglobin concentration ($= -0.0057, p=0.14;

controlling for gender).

Symptom/Medical History Survey

Symptoms suggestive of excessive exposure to

solvents were prevalent among all workers surveyed

(Table 6). Among these symptoms, having a

headache at least once per week, having painful

tingling in hands or feet, reporting a tremor, and

“feeling drunk” when not drinking, were all reported

more commonly among sprayers compared to nonsprayers, although none of the differences were

statistically significant (Table 6). Further analyses of

symptoms were performed for the 32 persons who

had participated in PBZ exposure sampling.

Analyses of PBZ 1-BP exposure among employees

by presence or absence of symptoms are reported in

Table 7. For each of the symptoms evaluated, air

concentrations of 1-BP were not statistically different

between those employees reporting the symptom

compared to those not reporting the symptom.

Questions concerning reproductive health were

asked in the questionnaire in several ways. In

response to the question “Have you ever been to the

doctor for reproductive/fertility problems,” one

participant answered yes and 42 answered no. The

one person answering yes worked in the Saw

department and (compared to other sampled

employees) had a relatively low PBZ air

concentration of 1-BP. Of the 41 participants

answering question concerning fertility, two of nine

males, and one of 32 females, reported that they have

failed to have a child after attempting for a full year.

The individual exposures to 1-BP for those three

individuals ranged from 110 - 157 ppm.

Second NIOSH Survey

Exposure Assessment

The data from the 30 full-shift 1-BP and 2-BP

inhalation exposure measurements are shown in

Appendix 2, and are summarized for 1-BP in Table

8 and for 2-BP in Table 9. The mean 1-BP exposure

concentration was 19.0 ppm, and the measurements

ranged from 1.2 to 58.0 ppm. The Covers

department had the highest mean 1-BP exposure

level (29.2 ppm), followed by the Assembly

department with a mean level of 18.8 ppm and the

Saw department with a mean level of 1.8 ppm. Eight

of the 12 (66.7%) 1-BP exposure measurements from

the Covers department exceeded 25 ppm; two of the

11 (18.1%) 1-BP exposure measurements from the

Assembly department exceeded 25 ppm.

The mean 2-BP exposure concentration was 0.14

ppm; concentrations ranged from below the MDC

(none detected) to 0.55 ppm. The highest 2-BP

exposures were found in the Assembly department

(mean of 0.30 ppm), followed by the Covers

department (0.06 ppm) and the Saw department (0.04

ppm). Two of the 30 2-BP exposure measurements

were below the MDC, and none of the measurements

exceeded the South Korean exposure limit.

Twelve short-term (15-minute) 1-BP and 2-BP

inhalation exposure measurements were collected

from sprayers in the Assembly and Covers

departments (Table 10). These measurements were

collected to document peak 1-BP and 2-BP exposure

concentrations during spray adhesive applications.

The 1-BP short-term exposures ranged from 12.3 to

26.0 ppm in the Assembly department, and from 13.4

to 95.8 ppm in the Covers department. In addition,

the 2-BP short- term exposures ranged from 0.2 to

0.4 in the Assembly department, and from below the

MDC to 0.1 ppm in the Covers department.

Area air sampling was conducted at five randomly

selected work stations in the Sew department to

estimate employees' 1-BP and 2-BP exposures. The

airborne concentration data from this sampling are

shown in Table 11. The 1-BP concentrations in the

Sew department ranged from 1.1 to 1.9 ppm, and no
Page 10 Health Hazard Evaluation Report No. 98-0153-2883

2-BP was detected in any of the five samples

collected in this department (2-BP MDC of 0.01

ppm).

Table 12 contains several comparisons between the

exposure data collected during the first NIOSH

survey (November 1998) and the second NIOSH

survey (November 2000). Considering all 1-BP

exposure data collected during these two site visits,

the mean exposure levels were reduced from 168.9

ppm to 19.0 ppm. 1-BP exposures in the Sew and

Saw departments have been reduced from over 100

ppm to less than 2 ppm, 1-BP exposures in the

Assembly department have been reduced from a

mean of 169.8 to 18.8 ppm, and those in the Covers

department from 197.0 to 29.2 ppm.

Ventilation Assessment

The average velocity of air flowing into the three

spray booths (1-3) measured during the follow-up

ventilation assessment in the Assembly area was

approximately 100 ft/min, and the average velocity

for the six booths (4-9) in the Covers area was

approximately 125 ft/min (Table 13). Both of the

values are below the recommended 150 ft/min;

however, the hoods performed well based on air-flow

visualization, with air flowing into all booths all

across the face of each booth and being drawn

decisively to the back of the booths and exhausted.

No air from inside the booths was observed to escape

into the room. The percent openness of the filters

ranged from 52% to 98%. (Table 13) Although not

evident from the hood averages, the individual filter

average velocities were higher for filter sections that

were less clogged with spray adhesive.

For work performed inside the booths, air-flow

visualization indicated that very little, if any,

contaminant was recirculated into the worker’s

breathing zone. Observed work practices revealed

that some pieces were still sprayed outside the booth,

but this seemed to occur less frequently than

observed on the previous survey.

The plant was under negative pressure with respect to

the outside when the ventilation for all booths was

operating, but not to the extent that door

opening/closing and climate control were affected. A

make-up air unit had been installed to keep

infiltration of unconditioned air to a minimum when

all booths were on. 

DISCUSSION AND

CONCLUSIONS

Exposure Assessment

At the time of the first NIOSH survey, most workers

in the Assembly, Covers, and Saw departments were

exposed to 1-BP above 100 ppm as a TWA, and all

were exposed above the guideline of 25 ppm

proposed by Albemarle Corporation and the EPA.

Based on our area sampling, workers in the Sew

department were probably exposed to similar

concentrations of 1-BP. The fact that workers in the

Sew and Saw departments had high exposures

indicates that 1-BP vapors from the sprayers readily

migrated into their work areas. A comparison of the

workers’ exposures for the Covers department

sprayers and the Assembly department sprayers

during our first exposure assessment found no

significant difference in 1-BP concentrations

between these two groups. This indicated that the

spray booths in the Assembly department were

ineffective in reducing workers’ 1-BP exposures.

According to ACGIH, the velocity of air flowing into

half-height (e.g., table-top) spray booths should be

150 feet per minute (ft/min) for face areas over 4 sqft. The duct velocity should be 2000 ft/min.15

Based on these findings, the NIOSH investigators

recommended engineering controls for reducing 1-

BP exposures. Specifically, the recommendations

were for the installation of spray booths for all

adhesive spraying operations (including Covers and

Assembly departments) based on designs of booths

used in spray painting operations. Air flow rates had

also been found to be inadequate, and

recommendations were provided for increasing the

air flow capacity.
Health Hazard Evaluation Report No. 98-0153-2883 Page 11

Following the installation of the spray booths in the

Covers and Assembly departments by Custom

Products, the second exposure assessment

documented significantly reduced air concentrations

of 1-BP, though some employees were still exposed

to concentrations of 1-BP above 25 ppm.

Specifically, 18% of the exposure measurements

from the Assembly department and 67% of the

exposure measurements from the Covers department

exceeded 25 ppm during the second exposure

assessment. The data from the second survey did,

however, indicate that 1-BP concentrations were

reduced to # 2 ppm in the Sew (area samples) and

Saw departments.

We observed less-than-recommended average face

velocity for the spray booths at our follow-up

ventilation assessment; a reason for this may be filter

clogging with spray adhesive. When a filter is

clogged with adhesive, the flow of air is restricted

and less air is able to be drawn through the booth.

Based on the velocities being drawn through

unclogged filters, it is estimated that the average face

velocity of all the booths could be approximately 150

ft/min with all new filters. Replacing filters when

then become 50 percent clogged would limit the face

velocity degradation, keeping the average face

velocity closer to the recommended value.

No 2-BP exposures above 1 ppm were found in any

of the departments. We observed that the 2-BP

exposures were higher in the Assembly department

sprayers when compared to the Covers department

sprayers. The mean 2-BP exposure in Assembly

sprayers was 0.33 ppm, whereas the mean exposure

for the Covers sprayers was 0.07 ppm. One

difference between the two departments that may

account for this is the use of two different brands of

spray adhesive: the Assembly department used

Whisper Spray, while the Covers department used

Fire Retardant Soft Seam 6460. The difference in

2-BP exposure between the two departments may

indicate there is more 2-BP contaminant in the

Whisper Spray compared to the Fire Retardant Soft

Seam 6460. NIOSH investigators believe it is

prudent to use a spray adhesive formulation with the

lowest concentration of 2-BP.

1-BP Exposure and Health

Effects

Although we found that Assembly and Covers

departments employees at Custom Products continue

to be exposed to 1-BP after installation of

engineering controls, we are unable to determine if

these exposures constitute a health hazard. Our

assessment of health effects among Custom Products

employees was limited to the questionnaire (selfreports of symptoms and medical concerns) and CBC

testing among employees agreeing to participate in

our survey. Selected symptoms consistent with, but

not specific for, excessive exposure to solvents were

prevalent among the workers surveyed, all of whom

were exposed to 1-BP. Analysis of the symptom data

did not reveal meaningful relationships with exposure

levels. CBC testing found no clinically relevant

abnormalities in the cell and platelet counts, and our

statistical analyses of the individual cell and platelet

counts and hemoglobin concentrations by exposure

to 1-BP revealed no statistically significant findings

within the normal ranges of the CBC indices.

Several factors, including the relatively low

participation rate, the small number of participants,

and the fact that all the participants in our survey

were exposed to 1-BP limited our ability to assess

potential health effects.

There are very little published data on human health

effects associated with 1-BP exposure, and a limited

amount of toxicologic data from studies in animals

(see Appendix 3). The exposure criteria of 25 ppm

discussed above are based on preliminary

evaluations of limited data. Considering the lack of

data concerning 1-BP exposure and possible human

health effects, and while further data are being

collected, NIOSH investigators believe that

occupational exposure to 1-BP and 2-BP should be

minimized. As more data are gathered concerning

recommended exposure guidelines for 1-BP, it is

reasonable to use the 25 ppm guideline that has been

suggested by some in industry and by the EPA. We

have shown in this HHE that implementation of

standard engineering controls are effective in greatly

reducing worker exposure to 1-BP. While further

engineering controls (such as improved ventilation)
Page 12 Health Hazard Evaluation Report No. 98-0153-2883

1. NIOSH [1992]. Recommendations for

occupational safety and health: compendium of

policy documents and statements. Cincinnati, OH:

U.S. Department of Health and Human Services,

Public Health Service, Centers for Disease Control

and Prevention, National Institute for

would be a means to further reduce exposures, other

important factors in minimizing exposure to 1-BP are

improved employee education and work practices.

Specifically, Custom Products must first ensure that

spray booths are designed properly and are adequate

for workers’ tasks. Training, and periodic re-training,

concerning proper work practices involved with use

of the spray booths (such as performing all spraying

inside the spray booths) is indicated to ensure that

existing engineering controls work as designed.

RECOMMENDATIONS

1. Custom Products should ensure that spray booths

in the production area are designed to be adequate for

the job tasks being performed.

2. Custom Products should inspect the spray booth

filters regularly as part of a routine maintenance

program. A filter should be replaced with a new filter

when most of the filter is covered with some

adhesive – this determination should be made by

qualitative evaluation of the filters by a person with

experience in maintaining these types of spray

booths.

3. Custom Products should educate and train

employees concerning the importance of proper use

of all spray booths; specifically, employees should be

educated and trained concerning the importance of

performing all spraying activities inside a spray

booth.

4. Custom Products should reevaluate employee

exposures to 1-BP in the Covers and Assembly areas

after maintenance procedures for the spray booths

have been maximized (for example, regular filter

maintenance being practiced) and after appropriate

work practices are being routinely practiced (for

example, all spraying tasks being performed inside

the spray booths). As more data are being gathered

concerning recommended exposure guidelines for 1-

BP, it is reasonable to use the 25 ppm guideline that

has been suggested by some in the industry and by

the EPA. Engineering (such as ventilation) and

administrative (such as product substitution and

change in work practices) are the recommended

types of controls that should be used to decrease

occupational exposures to substances in the

workplace.

5. Personal protective equipment is the least

desirable method of exposure control. In general,

NIOSH recommends PPE be used as an interim

solution before the installation and testing of new

exposure controls, and when

engineering/administrative controls have not

successfully lowered exposures. The following is

information relevant to the use of personal protective

equipment in workplaces where there may be

occupational exposure to 1-BP. 

a. For protection from dermal exposures, gloves

and aprons made from flexible laminates (e.g.,

VitonTM, 4HTM (PE/EVAL), Silver ShieldTM) can be

used.

b. If respirators are used for protection from

inhalation exposures to 1-BP, NIOSH-approved

air-purifying respirator with organic vapor cartridges

should be used. Respirators should only be used in

the context of a comprehensive respiratory protection

program.16 Respirator users must be trained, fittested, and medically cleared for their assigned

respirator.

6. Custom Products should consider the extent of

2-BP contamination when selecting a 1-BP-based

adhesive. If 1-BP-based adhesives are used, those

adhesives which have the minimum level 2-BP

contamination should be selected for use.

7. Custom Products should remain up-to-date with

ongoing development of guidelines concerning

occupational exposure to 1-BP, and also with any

regulatory activities occurring concerning the

bromopropanes. 

REFERENCES
Health Hazard Evaluation Report No. 98-0153-2883 Page 13

Occupational Safety and Health, DHHS (NIOSH)

Publication No. 92-100.

2. ACGIH [2001]. 2001 TLVs® and BEIs®:

threshold limit values for chemical substances and

physical agents. Cincinnati, OH: American

Conference of Governmental Industrial

Hygienists.

3. CFR [1997]. 29 CFR 1910.1000. Code of

Federal Regulations. Washington, DC: U.S.

Government Printing Office, Office of the Federal

Register.

4. Fensterbeim RJ [2000]. Letter of March 15,

2000 from Robert J. Fensterbeim, Brominated

Solvents Consortium to the TSCA 8(e)

Coordinator, Document Control Office, U.S.

Environmental Protection Agency.

5. Smith RL [2000]. Presentation titled “NPropyl Bromide” which was given on November

6, 2000, at a meeting between the U.S.

Environmental Protection Agency and the

Brominated Solvents Consortium.

6. EPA [2002]. Unpublished draft document:

Acceptable Industrial Exposure Limit for NPropyl Bromide. 

7. Yu IJ, Kim HY, Lim CH, et al. [1999]. The

occupational exposure level (OEL) for

2-bromopropane: the first OEL established by

Korea. Appl Occup Environ Hyg 14:356–358.

8. Park JS, Kim Y, Park DW, et al. [1997]. An

outbreak of hematopoietic and reproductive

disorders due to solvents containing 2-

bromopropane in an electronic factory, South

Korea: epidemiological survey. J Occup Health

39:138–143.

9. Kim Y, Jung K, Hwan T, et al. [1996].

Hematopoietic and reproductive hazards of South

Korean electronics workers exposed to solvents

containing 2-bromopropane. Scand J Work

Environ Health 22:387–391.

10. Ichihara Y, Yu S, Kamijima M, et al. [1997].

An occupational health investigation of a factory

producing 2-bromopropane in China. J Occup

Health 39 suppl: S327.

11. Ichihara G, Aseda N, Kumazawa T, et al.

[1997]. Testicular and hematopoietic toxicity of

2-bromopropane, a substitute for ozone layer

depleting chlorofluorocarbons. J Occup Health

39:57–63.

12. Kamijima M, Ichihara G, Yu X, et al. [1997].

Disruption of ovarian cyclicity due to

2-bromopropane in the rat. J Occup Health

39:3–4.

13. Yu IJ, Chung YH, Lim CH, et al. [1997].

Reproductive toxicity of 2-bromopropane in

Sprague Dawley Rats. Scand J Work Environ

Health 23:281–288.

14. Lim CH, Maeng SH, Lee JY, et al. [1997].

Effects of 2-bromopropane on the female

reproductive function in Sprague Dawley rats. Ind

Health 35:278–284.

15. ACGIH [2001]. Industrial Ventilation, 24st

Edition, A Manual of Recommended Practice.

Cincinnati, OH: American Conference of

Governmental Industrial Hygienists. pages 10-113

- 10-115.

16. CFR [2000]. 29 CFR 1910.134. Code of

Federal Regulations. Respiratory Protection.

Washington, DC: U.S. Government Printing

Office, Office of the Federal Register.
Page 14 Health Hazard Evaluation Report No. 98-0153-2883

TABLE 1

Descriptive Statistics for 1-Bromopropane Exposure1

HETA 98-0153, Custom Products, Inc.

November 11-12, 1998

Sample Set (Number2) 1-Bromopropane Concentration

Mean3 Minimum 3 Maximum3

All Exposures (69) 168.9 60.0 381.2

Assembly (36)4 169.8 60.0 250.7

Sprayers (15)

Assemblers (20)

193.0

154.7

115.3

60.0

250.7

234.9

Covers (21) 197.0 117.3 381.2

Saw (12) 117.1 85.1 159.2

1 These statistics are determined using the exposure data in Appendix I. All exposure data are full-shift time-weighted

average air samples collected from each worker’s breathing zone. 2 Number of full-shift, time-weighted average exposures in the given sample set. 3

 Numbers in these columns represent the mean (average), minimum, or maximum 1-bromopropane exposure concentrations

in the given sample set. The concentration data are in units of parts per million (ppm) of 

1-bromopropane. 4 Data from one supervisor omitted.
Health Hazard Evaluation Report No. 98-0153-2883 Page 15

TABLE 2

Results from Area Air Sampling for 1-Bromopropane

HETA 98-0153, Custom Products, Inc.

First NIOSH Survey, November 11-12, 1998

Location Sample StartStop TimeSample Volume1 Concentration2

Sew 0757-1531 26.2 115.8 

Sew 0757-1531 22.8 122.4 

Sew 0757-1531 27.1 160.9 

Sew 0757-1531 27.1 124.0 

Sew 0757-1531 22.7 126.1 

Sew 0757-1531 22.6 123.3 

Sew 0747-1533 23.3 124.6 

Sew 0749-1533 23.2 107.3 

Sew 0750-1533 23.2 143.7 

Sew 0752-1533 26.6 126.0 

Sew 0751-1533 23.0 135.1 

Minimum Detectable Concentration (MDC) 0.01

Minimum Quantifiable Concentration (MQC) 0.03

1 Sample volumes are in liters (L) of air. 2 The concentration data are in units of parts per million (ppm) of 1-bromopropane.
Page 16 Health Hazard Evaluation Report No. 98-0153-2883

TABLE 3

Exhaust Flow Rates and Face Velocities for each Fabricated Spray Booth

HETA 98-0153, Custom Products, Inc.

First NIOSH Survey, November 11-12, 1998

Booth ID# Estimated

Exhaust Flow

Rate (CFM)1

Calculated Average

Velocity Over Full Face

of Booth (ft/min)2

Measured Average Face

Velocity Over Top Half

of Booth (ft/min)2

1 7953 253 40

2 4013 133 31

3 NM4 NM4 24

4 779 25 NM4

5 6243 203 27

 1

 Units are in cubic feet of air per minute

2

 Units are in feet per minute. The recommended rate is 150 ft/min.

3 The reported value is an average of two measurements. 4 NM - No measurement. The measurements could not be completed due to recurring fan shut-off during employee

break time when measurements were being made. 5 Not applicable
Health Hazard Evaluation Report No. 98-0153-2883 Page 17

TABLE 4

HETA 98-0153, Custom Products

Description of the 43 Medical Survey Participants

Gender 34 (79%) female; 9 (21%) male

Age (years) Mean 31; Range 18-64

Work Location Saw department - 7 participants

Covers department - 18 participants

Assembly department - 18 participants (6 sprayers, 12

assemblers)

Exposure Category, Number in

Category, Mean Exposure

(parts per million [ppm] 1-

bromopropane)

Other (Saw department and one supervisor from Covers

department), N=8, 117 ppm

Assemblers, N=12, 155 ppm

Sprayers (Covers and Assembly departments), N=23, 195 ppm

Median (Range) Length of Time

Working at Current Job (years) 

Saw department - 9 years (1 year - 37 years)

Covers department - 4 years (3 months - 8 years)

Assembly department - 4 years (6 months - 10 years)

TABLE 5

HETA 98-0153, Custom Products

Median Value for Blood Count Test Results Among 43 Participants in the Medical Survey, By Exposure

Category

Exposure

Category1

Red Blood Cell

Count 2

Hemoglobin

Concentration3

White Blood Cell

Count4

Platelet Count5

Other 4.5 14.1 6.7 185

Assemblers 4.3 13.6 6.6 203

Sprayers 4.36 13.57 6.7 207

1

 Others includes Saw department employees and supervisor from Covers department. 2

 million cells per cubic millimeter (mm3)

3

 grams per deciliter

4

 thousand cells per mm3

5

 thousand per mm3

6

 Wilcoxon two sample test for comparison between sprayers and non-sprayers p=0.15 7

 Wilcoxon two sample test for comparison between sprayers and non-sprayers p=0.18
Page 18 Health Hazard Evaluation Report No. 98-0153-2883

TABLE 6

HETA 98-0153, Custom Products

Number of Participants with Specific Symptoms Grouped by Exposure Category, With Prevalence Ratio an

Total Number of Participants = 43

Exposure

category1

Painful Tingling2

# (%) Yes

Tremor3

 # (%) Yes

Headache4

# (%) Yes

Felt “Drunk”5

# (%) Yes

Abnormal Fatigue

# (%) Yes

Other 2 (25) 3 (38) 4 (50) 3 (38) 4 (50) 

Assemblers 4 (33) 3 (25) 4 (33) 5 (42) 6 (50) 

Sprayers 12 (54) 10 (43) 14 (61) 10 (45) 9 (39) 

Prevalence

Ratio (95% CI)

1.8 (0.8 - 3.9) 1.4 (0.6 - 3.3) 1.5 (0.8 - 2.9) 1.1 (0.6 - 2.3) 0.8 (0.4 - 1.5) 

1 Others includes Saw department employees and supervisor from Covers department. 2 Painful tingling in your hands or feet 3 Tremor (trembling in your hands)4 Headache at least once per week.5 Positive response to the question: “Have you felt “drunk” when you have not been drinking?”6 Prevalence ratio and 95% CI for prevalence of symptom among sprayers compared to that among non-sprayers.
Health Hazard Evaluation Report No. 98-0153-2883 Page 19

TABLE 7

Mean PBZ 1-BP Exposure Among Persons Reporting Presence/Absence of Symptoms

HETA 98-0153, Custom Products

Symptom Response (Number) Mean 1-BP (ppm) 

Headache2 No (N=16) 173 

Yes (N=16) 172

Abnormal Fatigue No (N=19) 172 

Yes (N=13) 172

Problem Concentrating No (N=18) 165 

Yes (N=13) 182

Feel “Drunk”3 No (N=18) 170 

Yes (N=13) 174

Painful tingling in your hands or feet No (N=19) 164 

Yes (N=12) 187

Tremor (trembling in your hands) No (N=18) 165 

Yes (N=14) 182

1 Two-sample t-test, two sided2 Headache at least once per week.3 Positive response to the question: “Have you felt “drunk” when you have not been drinking?”

TABLE 8
Page 20 Health Hazard Evaluation Report No. 98-0153-2883

Descriptive Statistics for 1-Bromopropane Exposure1

HETA 98-0153, Custom Products, Inc.

Second NIOSH Survey, November 16, 2000

Sample Set (Number2)

1-Bromopropane Concentration

Mean3 Minimum 3 Maximum3

All Exposures (30) 19.0 1.2 58.0

Assembly (11) 18.8 6.1 32.0

Covers (12) 29.2 2.8 58.0

Saw (6) 1.8 1.6 2.0

Sew (1) 1.2 NA4 NA

1 All exposure data are full-shift time-weighted average air samples collected from each worker’s breathing zone. 2

 Number of full-shift, time-weighted average exposures in the given sample set. 3

 Numbers in these columns represent the mean (average), minimum, or maximum 1-bromopropane exposure concentrations in the

given sample set. The concentration data are in units of parts per million (ppm) of 1-bromopropane. 4 Not applicable.
Health Hazard Evaluation Report No. 98-0153-2883 Page 21

TABLE 9

Descriptive Statistics for 2-Bromopropane PBZ Exposure1

HETA 98-0153, Custom Products, Inc.

Second NIOSH Survey, November 16, 2000

Sample Set (Number2)

2-Bromopropane Concentration

Mean3 Minimum 3 Maximum3

All Exposures (30) 0.14 <0.01 0.55

Assembly (11) 0.30 0.10 0.55

Covers (12) 0.06 (0.02) 0.11

Saw (6) 0.04 <0.01 0.05

Sew (1) < 0.01 NA4 NA

1 All exposure data are full-shift time-weighted average air samples collected from each worker’s breathing zone. 2

 Number of full-shift, time-weighted average exposures in the given sample set. 3

 Numbers in these columns represent the mean (average), minimum, or maximum 2-bromopropane exposure concentrations in the

given sample set. The concentration data are in units of parts per million (ppm) of 2-bromopropane. Concentrations in parentheses

are between the MDC and MQC and are considered semi-quantitative. Concentrations preceded by a “less than” (<) symbol are

below the MDC. 4 Not applicable.
Page 22 Health Hazard Evaluation Report No. 98-0153-2883

TABLE 10

Short-Term Exposures to 1- and 2-Bromopropane

HETA 98-0153, Custom Products, Inc.

Second NIOSH Survey, November 16, 2000

Job Title Location

Elapsed

Sample

Time1

Sample

Volume2

Concentration3

1-BP 2-BP

Sprayer Assembly-1 15 3.7 19.0 0.3

Sprayer Assembly-2 15 3.7 16.6 0.3

Sprayer Assembly-3 15 3.7 12.3 0.2

Sprayer Assembly-2 16 4.0 17.1 0.2

Sprayer Assembly-1 16 3.9 26.0 0.4

Sprayer Assembly-3 15 3.7 12.9 (0.2)

Sprayer Covers-2 17 4.2 20.8 ND

Sprayer Covers-1 17 4.1 95.8 (0.1)

Sprayer Covers-2 15 3.7 30.0 ND

Sprayer Covers-5 15 3.7 52.6 (0.1)

Sprayer Covers-4 15 3.7 26.6 (0.1)

Sprayer Covers-6 15 3.7 13.4 ND

Minimum Detectable Concentration (MDC) 0.1 0.1

Minimum Quantifiable Concentration (MQC) 0.2 0.2

1

 Elapsed sample time is in minutes.

2

 Sample volume is in liters.

3

 The exposure concentrations are in parts per million (ppm). Concentrations in parentheses are between the MDC and MQC and are

considered semi-quantitative. ND - none detected, less than the MDC.
Health Hazard Evaluation Report No. 98-0153-2883 Page 23

TABLE 11

Results from Area Air Sampling for 1- and 2-Bromopropane

HETA 98-0153, Custom Products, Inc.

Second NIOSH Survey, November 11-12, 1998

Location Sample

Time Sample Volume1

Concentration2

1-BP 2-BP

Sew 0735-1524 23.3 1.4 ND

Sew 0735-1523 25.3 1.3 ND

Sew 0735-1517 23.3 1.2 ND

Sew 0735-1522 25.2 1.1 ND

Sew Together 0752-1523 22.1 1.9 ND

Minimum Detectable Concentration (MDC) 0.01 0.01

Minimum Quantifiable Concentration (MQC) 0.03 0.03 1 Sample volumes are in liters (L) of air. 2 The concentration data are in units of parts per million (ppm); ND - none detected, less than the MDC.
Page 24 Health Hazard Evaluation Report No. 98-0153-2883

TABLE 12

Comparison Between the Mean Full-shift 1-BP Exposures Measured During the November 1998 Survey

Versus the November 2000 Survey

HETA 98-0153, Custom Products, Inc.

November 16, 2000

Sample Set November 1998 Mean

1-BP Exposures1

November 2000 Mean

1-BP Exposures1

All Exposure Data 168.9 19.0

 Assembly Data

 Sprayers

 Assemblers

169.8

193.0

154.7

18.8

21.7

19.5

 Covers Data 197.0 29.2

 Saw Data 117.1 1.8

 Sew Data2 128.1 1.4

1

 Exposures are in parts per million (ppm).

2

 Exposures are estimated from area air sampling data.
Health Hazard Evaluation Report No. 98-0153-2883 Page 25

TABLE 13

Airflow and filter openness for all adhesive spray booths

HETA 98-0153, Custom Products, Inc.

April 19, 2001

Hood number

Flow rate

CFM

Average face

velocity

ft/min

Filter

percent

openness

1 1978 106 72

2 1823 98 52

3 2192 117 67

4 4106 134 82

5 4006 131 98

6 3747 122 88

7 3960 129 88

8 3942 129 96

9 4065 133 96
Page 26 Health Hazard Evaluation Report No. 98-0153-2883

APPENDIX 1

 Discussion and Recommendations From First HHE Ventilation Assessment at Custom Products

Based on the initial NIOSH exposure and ventilation assessments, spray booths are needed for spraying

operations at Custom Products. Air flow rates through existing spray booths in the Assembly area are

inadequate, and spray booths have not yet been installed in the Covers area. Properly designed spray booths

with adequate air flow rates should be installed at each work station where spraying operations are performed.

Although an adhesive, not paint, is being sprayed, a spray booth design similar to the paint spray booths

presented in drawing VS-75-01 in the ACGIH Industrial Ventilation Manual is recommended for the Assembly

area. New booths could be sized similarly to existing booths, measuring approximately 60 inches wide and 76

inches in overall height. For a large booth with the operator standing outside the booth, a minimum flow rate of

100 CFM/sq-ft is recommended. For a booth with an opening of the size mentioned above, over 3000 cubic

feet per minute (CFM) of air flow would be needed. This air flow requirement can be reduced by raising the

floor of the spray booth 28 inches above the plant floor. The work is currently placed on an adjustable stand,

which could still be used in the new booths; however, the area below the stand platform is not needed for spray

operations. Decreasing the area of the face of the booth by installing a floor in the booth just below the lowest

level of the adjustable work platform will allow the required flow rate to be reduced to approximately 2000

CFM.

For the Covers area, smaller (table-top) booths may be more practical, providing protection with a smaller

requirement for exhaust ventilation volume flow rate. The booth should be 12 inches wider and 12 inches

higher than the work size. For a typical first-class airplane seat, a booth 42 inches wide and 22 inches high

should be adequate. For a small booth, a minimum flow rate of 150 CFM/sq-ft is recommended. For a booth

with an opening of the size recommended above, 965 CFM would be needed. 

It would be expected that the baffles and other interior surfaces of the booth would become covered with spray

adhesive. To facilitate cleaning, each baffle could be hung on hooks at the two upper corners and held in

position by supports at the two bottom corners. This could simplify removal and reinsertion of the baffles,

making both the baffles and the walls of the booth easier to clean.

ACGIH recommends a minimum duct velocity of 2000 ft/min. For the portion of the ductwork carrying the

2000 CFM flow rate from a single booth, the existing 12-inch diameter ductwork should be adequate. If

excessive noise becomes a problem in the portion of the ductwork carrying the 4000 CFM flow rate from two

booths, substituting 17-inch diameter ductwork should reduce the noise. For the vertical discharge portion of

the ductwork on the roof of the building, an offset elbow or a vertical discharge stackhead design is

recommended for rain protection.

The negative pressure condition inside the building with respect to the outside was consistent with the

provision of local exhaust ventilation without providing additional make-up air. At the time of the survey, the

infiltration of outside air was slight, and temperature and relative humidity were within recommended limits;

however, additional make-up air may need to be provided by the air-conditioning system when more local

exhaust ventilation is installed. A potential recirculation problem exists on the roof with the exhaust fans

discharge velocity and duct height. The intakes and discharges for all fans are generally close to the surface of

the roof and close to the air intakes for air-conditioning units. It is possible that there may be some reentry of

exhausted spray adhesive vapors, depending on the direction the wind is blowing. 

On the roof, ventilation inlets and outlets should be located to minimize reentry of air from contaminated

sources. The minimum stack height should cause the flow of the discharge plume to be above the building
Health Hazard Evaluation Report No. 98-0153-2883 Page 27

inlets and the building recirculation cavity. For many single-story buildings, an exhaust stack height of 16 ft

has been found adequate for discharging contaminants above the roof cavity. A design velocity of 2560 ft/min

is recommended.

Reference

ACGIH [2001]. Industrial Ventilation, 24th Edition, A Manual of Recommended Practice. Cincinnati, OH: 

American Conference of Governmental Industrial Hygienists. pages 10-113 - 10-115.

ASHRAE [1985]. Air Flow Around Buildings. In: Fundamentals, 1985 ASHRAE Handbook.. Atlanta, GA: 

American Society of Heating, Refrigerating, and Air–Conditioning Engineers, Inc., chap 14.
Page 28 Health Hazard Evaluation Report No. 98-0153-2883

APPENDIX 2

Worker’s Full-Shift Breathing Zone Exposure Data for 1-Bromopropane

November 11-12, 1998

Department Job Title Sample

Time 

Sample Volume1 1-BP Concentration2

Assembly Sprayer 0710-1518 26.8 115.3 

Assembly Assembler 0712-1521 25.1 128.3 

Assembly Assembler 0713-1517 24.6 135.6 

Assembly Sprayer 0715-1521 24.8 150.3 

Assembly Sprayer 1100-1443 11.4 242.0 

Assembly Assembler 0719-1528 18.6 193.3 

Assembly Assembler 0719-1522 24.9 147.7 

Assembly Assembler 0726-1523 24.3 123.1 

Assembly Sprayer 0722-0928 6.3 156.5 

Assembly Supervisor 0724-1528 24.8 124.9 

Assembly Assembler 0728-1332 18.7 234.9 

Assembly Sprayer 0729-1522 24.3 249.1 

Assembly Sprayer 0729-1333 18.5 225.8 

Assembly Sprayer 0730-1310 12.8 198.9 

Assembly Assembler 0920-1524 18.5 199.3 

Assembly Assembler 0731-1423 20.6 222.4 

Assembly Sprayer 0732-1526 24.3 250.7 

Assembly Assembler 0733-1523 20.4 60.0 

Assembly Assembler 0918-1526 18.7 151.2 

Assembly Sprayer 0735-1521 23.9 227.1 

Assembly Assembler 0732-1534 24.1 121.3 

Assembly Sprayer 0730-1532 24.5 190.8 

Assembly Assembler 0730-1530 24.0 129.6 
Department Job Title Sample

Time 

Sample Volume1 1-BP Concentration2

Health Hazard Evaluation Report No. 98-0153-2883 Page 29

Assembly Assembler 0730-1529 24.5 183.6 

Assembly Assembler 0730-1531 24.5 155.0 

Assembly Sprayer 0730-1410 20.0 211.7 

Assembly Sprayer 0730-1529 24.0 188.0 

Assembly Assembler 0732-1531 24.0 184.6 

Assembly Sprayer 0732-1529 24.5 184.8 

Assembly Sprayer 0732-1527 24.3 132.8 

Assembly Assembler 0734-1533 23.8 144.8 

Assembly Sprayer 0735-1533 18.1 171.4 

Assembly Assembler 0735-1533 24.2 179.6 

Assembly Assembler 0735-1533 24.3 158.3 

Assembly Assembler 0737-1533 24.3 127.2 

Assembly Assembler 0738-1533 23.7 114.1 

Covers Sprayer 0700-1533 25.0 211.1 

Covers Sprayer 0700-1533 25.2 232.7 

Covers Sprayer 0700-1533 25.5 157.0 

Covers Sprayer 0701-1533 24.8 235.0 

Covers Sprayer 0701-1533 24.8 278.5 

Covers Sprayer 0700-1533 25.3 381.2 

Covers Sprayer 0705-1533 24.7 241.1 

Covers Sprayer 0708-1533 25.3 147.3 

Covers Sprayer 0709-1533 24.7 181.4 

Covers Sprayer 0710-1533 24.6 264.8 

Covers Sprayer 0710-1533 25.1 161.0 

Covers Sprayer 0711-1533 11.4 176.3 
Department Job Title Sample

Time 

Sample Volume1 1-BP Concentration2

Page 30 Health Hazard Evaluation Report No. 98-0153-2883

Covers Sprayer 0712-1533 25.2 194.5 

Covers Sprayer 0713-1533 27.0 142.9 

Covers Sprayer 0713-1533 25.1 180.7 

Covers Sprayer 0715-1533 24.8 203.3 

Covers Sprayer 0716-1533 25.2 221.0 

Covers Sprayer 0716-1533 24.7 126.8 

Covers Sprayer 0719-1533 24.8 140.5 

Covers Sprayer 0720-1533 24.2 117.3 

Covers Sprayer 0724-1533 24.3 142.8 

Saw Operator 0737-1417 20.5 104.1 

Saw Operator 0925-1537 19.1 140.9 

Saw Operator 0741-1525 23.2 127.3 

Saw Supervisor 0742-1523 23.4 117.4 

Saw Operator 0745-1523 22.9 159.2 

Saw Operator 0747-1524 23.3 106.0 

Saw Operator 0748-1523 23.1 109.7 

Saw Operator 0749-1520 23.1 85.1 

Saw Operator 0750-1525 23.3 111.8 

Saw Operator 0751-1523 22.8 110.0 

Saw Operator 0915-1525 18.9 123.5 

Saw Supervisor 0730-1534 24.2 110.3 

Recommended Exposure Guideline 25 

Minimum Detectable Concentration (MDC) 0.01

Minimum Quantifiable Concentration (MQC) 0.03

1

 Sample volumes are in liters of air.
Health Hazard Evaluation Report No. 98-0153-2883 Page 31

2

 The 1-BP exposure concentrations are in parts per million. Concentrations in parentheses are between the MDC and MQC

and are considered semi-quantitative. ND - none detected, less than the MDC.
Page 32 Health Hazard Evaluation Report No. 98-0153-2883

APPENDIX 3

 Worker’s Full-Shift Breathing Zone Exposure Data for 1-BP and 2-BP

November 16, 2000

Job Title Department1 Sample

Time

Sample

Volume2

Concentration3

1-BP 2-BP

Assembler Assembly - 2 0705-1517 24.3 18.0 0.30

Assembler Assembly - 2 0706-1518 24.9 20.7 0.35

Sprayer Assembly - 2 0708-1519 24.3 32.0 0.48

Assembler Assembly - 1 0709-1519 24.2 9.9 0.20

Sprayer Assembly - 1 0710-1517 24.0 14.9 0.25

Assembler Assembly - 1 0711-1519 49.8 24.4 0.40

Assembler Assembly - 1 0712-1518 24.4 31.8 0.55

Assembler Assembly - 3 0714-1520 24.1 11.5 0.19

Sprayer Assembly - 3 0715-1520 24.1 18.1 0.26

Assembler Assembly - 3 0715-1519 24.0 19.9 0.21

Foreman Assembly 0756-1522 21.7 6.1 0.10

Sprayer Covers - 1 0719-1520 23.7 58.0 0.11

Sprayer Covers - 1 0720-1521 21.8 26.5 0.07

Sprayer Covers - 3 0722-1522 23.6 25.3 0.06

Sprayer Covers - 2 0723-1520 24.6 5.4 0.03

Sprayer Covers - 2 0723-1522 70.9 33.7 0.07

Sprayer Covers - 3 0725-1523 23.5 51.6 0.10

Sprayer Covers - 4 0904-1519 18.3 28.2 0.05

Sprayer Covers - 5 0727-1521 20.0 36.8 0.06

Sprayer Covers - 5 0730-1520 23.3 45.3 0.10

Sprayer Covers - 6 0730-1520 22.9 13.9 0.06

Sprayer Covers - 6 0730-1521 22.3 23.2 0.05

Foreman Covers 0734-1522 23.3 2.8 (0.02)

Foreman Sew 0739-1522 22.8 1.2 ND

Operator Saw 0741-1518 19.4 1.6 0.04

Operator Saw 0743-1519 24.3 1.6 ND

Operator Saw 0745-1517 22.5 2.0 0.05

Operator Saw 0747-1519 45.4 1.7 0.03

Operator Saw 0748-1518 22.1 1.9 0.04

Foreman Saw 0756-1521 91.6 1.8 0.05

Recommended Exposure Guideline 25 1 
Health Hazard Evaluation Report No. 98-0153-2883 Page 33

Minimum Detectable Concentration (MDC) 0.01 0.01

Minimum Quantifiable Concentration (MQC) 0.03 0.02

1

 Spray booth number where the air sample was collected; 2 Sample volumes are in liters of air; 3 The 1-BP and 2-BP exposure (ppm). 

Concentrations in parentheses are between the MDC and MQC (semi-quantitative). ND - none detected, less than the MDC.
Page 34 Health Hazard Evaluation Report No. 98-0153-2883

APPENDIX 4

Brominated Solvents Background and Significance

In 1990 the Clean Air Act (CAA) was amended to include more stringent provisions for the

protection of stratospheric ozone and the phase-out of several ozone-depleting substances under Title

VI of the law.1 The law targeted the complete phase-out of several substances including

chlorofluorocarbons, hydrochlorofluorocarbons, and methyl chloroform, each of which was being

used by industry at that time. Industrial applications of these substances included non-aerosol solvent

cleaning, adhesive coatings applications, and solvent applications.2 The CAA amendment provisions

were in part enacted to abide by the terms of a United Nations (UN) international agreement, The

Montreal Protocol on Substances that Deplete the Ozone Layer adopted in 1987, which committed to

reduce and eventually eliminate the use of ozone-depleting substances. As a result, several countries

discontinued and prohibited further use of ozone-depleting substances.3

 Under Section 612 of the

CAA, ozone-depleting substances were to be replaced with alternative substances or processes that

reduced the risks to human health and the environment.1

 To fulfill the law’s requirement, the

Environmental Protection Agency (EPA) initiated the Significant New Alternatives Policy (SNAP)

program intended to approve safe alternatives for ozone-depleting substances.4

The solvents 1-bromopropane (1-BP) and 2-bromopropane (2-BP) were introduced into workplaces

around the world as substitutes for ozone-depleting substances following initiation of the 1987 UN

international treaty. The physical properties of these two solvents, including high volatility and low

flammability, were seen as favorable characteristics for a non-aerosol solvent. Due to photochemical

breakdown, the solvents have a relatively short atmospheric half-life (17.5 to 24 days), possibly

decreasing their ozone-damaging capacity.5,6 

At the present time, 2-BP is not produced for commercial use in the United States (U.S.). However,

1-BP is produced and commercially available in the U.S. The purity of 1-BP is listed as 99% in

Material Safety Data Sheets (MSDS) from two laboratory reagent manufacturers.7,8 A 1999

Occupational Safety and Health Administration (OSHA) analysis of several commercial samples of

1-BP found them to contain 2-BP in concentrations ranging from 0.1 to 0.2 percent.9 A voluntary

consensus standard (D6368-00) published by the American Society For Testing and Materials has

since been released covering vapor degreasing and general grade 1-BP and specifies that the content

of 2-BP in these solvent grades remain below 0.1 percent.10 Currently only 1-BP is being reviewed

under the SNAP program as a potential alternative to ozone-depleting substances.2 At this time, the

EPA has not disapproved the use of 1-BP, so it may be used for any purpose in the U.S. (while 2-BP

may not).9

Review of Literature—

1-Bromopropane

Animal exposure studies have demonstrated reproductive toxicity for both male and female rats when

exposed to concentrations greater than or equal to 200 parts per million (ppm) of 1-BP.11,12 Two

studies noted mild hepatic changes in rats exposed to greater than or equal to 800 ppm of 1-BP; these

changes were considered adaptive and reversible due to the absence of other signs of

hepatotoxicity.11,13,14 Although 2-BP exposure has been associated with pancytopenia, animal studies
Health Hazard Evaluation Report No. 98-0153-2883 Page 35

evaluating potential hematopoietic effects of 1-BP exposure have yielded no firm conclusions. The

median lethal inhalation concentration of 1-BP for Sprague-Dawley rats has been estimated to be

14,374 ppm.13

Four studies have demonstrated some form of neurotoxicity in rats exposed to 1-BP. All studies

involved exposure concentrations greater than or equal to 800 ppm. Three of the studies

demonstrated decreased peripheral nerve functioning by electrophysiologic testing and morphologic

or histopathologic abnormalities of central and peripheral nerves.15,16,17 Two of these three studies

also demonstrated a prominent weakness of the hind limbs following exposure.15,17 A fourth study

demonstrated decreased peripheral nerve functioning by electrophysiologic testing alone.18 One of

the five studies established that the muscle weakness and decreased electrophysiologic findings were

both dependent on concentration and length of exposure period.17 This same study and one other

came to the conclusion that 1-BP was a more potent neurotoxicant than 2-BP; another study that

evaluated the neurotoxicity of both 1-BP and 2-BP was unable to conclude that 1-BP was a more

potent neurotoxicant.15,18 

A total of four persons with health effects considered related to 1-BP exposure have been described in

two published case reports. The first case report concerned a 19-year-old male working as a metal

‘stripper’.19 He was exposed on a daily basis over a two-month period to an industrial solvent

(containing greater than 95.5 percent 1-BP by weight) used for degreasing and cleaning. His right

hand was most commonly exposed to the solvent. The air concentration of 1-BP and type of

ventilation were not discussed in the article. Presenting symptoms included “numbness and mild but

progressive weakness of the proximal lower extremities and the right hand... transient dysphagia and

urinary difficulties.”19 The physical findings, magnetic resonance imaging (MRI) of the brain, and

electromyography (EMG) findings supported the diagnosis of a “primary demyelinating condition,

predominantly affecting the lower extremities, in the distribution of an acquired neuropathy, but with

evidence of central nervous system involvement as well.” The EMG did not indicate any evidence of

muscle denervation. The individual did demonstrate improvement following removal from exposure,

but was lost to follow-up before it was determined if the health effects would fully resolve.

The second case report concerned three females, ages 35, 30, and 50, each working at cushion

manufacturing companies in North Carolina.20 The workers sprayed glue (containing 55 percent 1-

BP as the base solvent) with a spray gun onto polyurethane foam pieces. A total of 15 workers

performed this process in an open work area. Exhaust ventilation provided at each workstation was

operated intermittently and workers wore latex gloves for dermal exposure protection. The first

worker’s symptoms developed one year following the replacement of a dichloromethane-based glue

with the 1-BP-based glue. The remaining two workers developed symptoms six months and two

months, respectively, following commencement of their employment in the exposure area. Airborne

exposures of the three workers were not well described; the case report did state that one worker was

found to have time-weighted average (TWA) exposures of between 60 to 261 ppm of 1-BP over

several days of monitoring 5 months after symptoms had started. 

“The three workers showed the common symptoms of staggering, numbness and

paresthesia/dysesthesia with a similar distribution in their feet, legs, thighs, lower back and hips as
Page 36 Health Hazard Evaluation Report No. 98-0153-2883

well as a remarkable decrease in vibration sense, along with various symptoms of the central nervous

system and autonomic symptoms.”20

Other symptoms experienced by the workers included temporary menstrual cycle disruption for two

of the three women, diarrhea, abnormal sweating, and urinary incontinence. The researchers

concluded that 1-BP likely caused the peripheral and central nervous system deficits and that the other

noted symptoms were likely related to autonomic system disruption secondary to 1-BP exposure. The

study did not indicate if the symptoms improved or resolved upon removal from exposure.

Limited information is available from an unpublished abstract submitted at the 2002 Annual Meeting

of the Society of Toxicology regarding the only 1-BP human health effect study performed to date.21

The study evaluated a group of 25 female workers, exposed to low levels of 1-BP, for neurological

effects, comparing them to a group of 27 unexposed controls. Neurobehavioral and

electrophysiological assessments of nerve function were performed on both groups. Because of the

limited nature of the information presented in this abstract, it is difficult to draw conclusions from this

study.

Review of Literature— 

2-Bromopropane

Following a report of the occurrence of secondary amenorrhea among female workers in a tactile

switch assembly section of a South Korean factory, two studies were performed to evaluate the health

effects of workers in the factory.22,23 The studies found background area air sample concentrations of

2-BP to range from 9.2 to 19.6 ppm. The concentration of 2-BP detected during a short-term sample

inside the hood of a cleaning bath was 4,140.7 ppm. One study theorized that workers might be

exposed to higher concentrations of 2-BP for short periods of time when performing operations at the

cleaning bath.22 The other study theorized that because there were two uncovered 2-BP baths in the

area and ventilated air was recirculated, 2-BP concentrations were routinely elevated in the work

area.23 Both studies concluded that 2-BP exposure was the probable cause of the health effects

(ovarian failure in females, azoospermia or oligospermia in males, and pancytopenia) noted in the

exposed workers. 

Following these reports, several studies designed to evaluate health effects associated with exposure

of rats to 2-BP were initiated; these studies demonstrated ovarian, testicular, and hematopoietic

dysfunction beginning at exposure levels of greater than 300 ppm or 250 milligram per kilogram

(mg/kg).24,25,26,27,28 Two studies recently demonstrated peripheral neurotoxic changes and peripheral

neuropathy in rats exposed to 1,000 ppm of 2-BP.18,29 The median lethal inhalation concentration of

2-BP for the Sprague-Dawley rat has been estimated to be 31,171 ppm.30 

One study has been conducted to evaluate the health effects of 2-BP on employees working at a 2-BP

manufacturing plant. During the study, conducted in 1996, worker breathing zone exposure

concentrations ranged from 0.80 to 16.18 ppm as an 8-hour TWA. The study included worker

interviews, medical examinations, and specific testing of reproductive and hematological indices. 

“No severe cases of reproductive or hematopoietic disorders were found at (exposures) less than 10
Health Hazard Evaluation Report No. 98-0153-2883 Page 37

ppm (TWA), but a possible adverse effect of 2-bromopropane on hematopoiesis could not be

disproved.”31

1-Bromopropane Biomarker of Exposure

A study has demonstrated that among seven different solvents, 1-BP was the only solvent that

significantly (p < 0.01) influenced the concentration of 1-BP and bromine in the urine of exposed

subjects, and thus either measure can be used as a biomarker of exposure.32 In that study, 1-BP

concentration in the urine was shown to be more highly correlated to the airborne 1-BP exposure (p <

0.01, r = 0.952) than was bromine concentration in the urine (p < 0.01, r = 0.738). However, urinary

1-BP detection requires gas chromatography-mass spectrometry (GCMS) instrumentation and the

specimen must be immediately analyzed after collection. Most clinical laboratories can perform

bromine detection, and analysis may be delayed without serious degradation of specimen quality. 

Cost constraints would be the main reason why bromine analysis might be chosen over GCMS

analysis in a study.
Page 38 Health Hazard Evaluation Report No. 98-0153-2883

1. United States Code [1990]. 42 USC 7401 et. seq. Washington, DC: U.S. Government Printing Office.

2. 65 Federal Register 78977 [2000]. Environmental Protection Agency: Protection of stratospheric ozone:

Notice 14 for significant new alternatives policy program; notice of acceptability; request for information.

3. United Nations Environmental Programme [2000]. Ozone Treaties.

[http://www.unep.ch/ozone/treaties.shtml]. Date accessed: May 5, 2002.

4. 58 Fed. Reg. 54892 [1993]. Environmental Protection Agency: Protection of stratospheric ozone; final

rule.

5. Donaghy T, Shanahan I, Hande M, Fitzpatrick S [1993]. Rate constants and atmospheric lifetimes for

the reactions of OH radicals and Cl atoms with haloalkanes. Int J Chem Kinet 25(4):273–84.

6. Meylan WM, Howard PH [1993]. Computer estimation of the atmospheric gas-phase reaction rate of

organic compounds with hydroxyl radicals and ozone. Chemosphere 26(12):2293–2300.

7. Aldrich Chemical Company. Material safety data sheet for 1-bromopropane, 99%. May 2002.

8. Acros Organics N.V. Material safety data sheet for 1-bromopropane, 99%. May 2002.

9. OSHA [1999]. Nomination of 1-bromopropane (1-BP) and 2-bromopropane (2-BP) for testing by the

National Toxicology Program. Washington, DC: Department of Labor, Directorate of Health Standards

Programs, U.S. Occupational Safety and Health Administration, DOL (OSHA).

10. ASTM [2001]. D6368-00 Standard specification for vapor-degreasing grade and general grade normalpropyl bromide. West Conshohocken, PA: American Society for Testing Materials.

11. Ichihara G, Yu X, Kitoh J, Asaeda N, Kumazawa T, Iwai H, Shibata E, Yamada T, Wang H, Xie Z,

Maeda K, Tsukamura H, Takeuchi Y [2000]. Reproductive toxicity of 1-bromopropane, a newly introduced

alternative to ozone layer depleting solvents, in male rats. Toxicological Sciences 54:416–423.

12. Stump D [2001]. An inhlation two-generation reproductive toxicity study of 1-bromopropane in rats.

Study No. WIL-380001. 

13. Kim HY, Chung YH, Jeong JH, Lee YM, Sur GS, Kang JK [1999]. Acute and repeated inhalation

toxicity of 1-bromopropane in SD rats. J Occup Health 41:121–128.

14. NTP [2002]. NTP-CERHR expert panel report on the reproductive and developmental toxcity of

1-bromopropane. Washington, DC: U.S. Department of Health and Human Services, National Institutes of

Health, National Institute of Environmental Health Sciences, National Toxicology Program, DHHS (NTP)

Publication No. NTP-CERHR-1-BP-02.

15. Yu X, Ichihara G, Kitoh J, Xie Z, Shibata E, Kamijima M, Takeuchi Y [2001]. Neurotoxicity of

2-bromopropane and 1-bromopropane, alternative solvents for chlorofluorocarbons. Environmental

Research 85(1):48–52.

APPENDIX 4 - REFERENCES
Health Hazard Evaluation Report No. 98-0153-2883 Page 39

16. Wang H, Ichihara G, Ito H, Kato K, Kitoh J, Yamada T, Yu X, Tsuboi S, Moriyama Y, Sakatani R,

Shibata E, Kamijima M, Itohara S, Takeuchi Y [2002]. Biochemical changes in the central nervous system

of rats exposed to 1-bromopropane for seven days. Toxicological Sciences 67:114–120.

17. Ichihara G, Kitoh J, Yu X, Aseda N, Iwai H, Kumazawa T, Shibata E, Yamada T, Wang H, Xei Z,

Takeuchi Y [2000]. 1-bromopropane, an alternative to ozone layer depleting solvents, is dose-dependently

neurotoxic to rats in long-term inhalation exposure. Toxicological Sciences 55:116–123.

18. Zhao W, Aoki K, Xie T, Misumi J [1999]. Electrophysiological changes induced by different doses of

1-bromopropane and 2-bromopropane. J Occup Health 41:1–7.

19. Sclar G [1999]. Encephalomyelo-radiculoneuropathy following exposure to an 

industrial solvent. Clinical Neurology and Neurosurgery 101:199–202.

20. Ichihara G, Miller JK, Ziolkowska A, Itohara S, Takeuchi Y [2002]. Neurological disorders in three

workers exposed to 1-bromopropane. J Occup Health 44:1–7.

21. Ichihara G, Li W, Shibata E, Ding X, Kamijima M, Wang H, Liang Y, Peng S, Itohara S, Fan Q,

Zhang Y, Zhong W, Wu X, Valentine WM, Takeuchi Y [2002]. Neurological abnormality in workers of

1-bromopropane factory [Abstract]. Presented at the 41st Annual Meeting of the Society of Toxicology,

Nashville, TN, March 17–21.

22. Kim Y, Jung K, Hwang T, Jung G, Kim H, Park H, Kim J, Park J, Park D, Park S, Choi K, Moon Y

[1996]. Hematopoietic and reproductive hazards of Korean electronic workers exposed to solvents containing

2-bromopropane. Scand J Work Environ Health 22:387–391.

23. Park J, Kim Y, Park DW, Choi KS, Park S, Moon Y [1997]. An outbreak of hematopoetic and

reproductive disorders due to solvents containing 2-bromopropane in an electronic factory, South Korea:

epidemiological survey. J Occup Health 39:138–143.

24. Kamijima M, Ichihara G, Yu X, Kitoh J, Tsukamura H, Maeda K, Yu X, Xie Z, Nakajima T, Asaeda N,

Hisanaga N, Takeuchi Y [1997]. Ovarian toxicity of 2-bromopropane in the non-pregnant female rat.

J Occup Health 39:144–149.

25. Kamijima M, Ichihara G, Yu X, Xie Z, Kitoh J, Tsukamura H, Maeda K, Nakajima T, Asaeda N,

Hisanaga N, Takeuchi Y [1997]. Disruption in ovarian cyclicity due to 2-bromopropane in the rat.

J Occup Health 39:3–4.

26. Lim CH, Maeng SH, Lee JY, Chung YH, Kim TG, Park JH, Moon YH, Yu IJ [1997]. Effects of

2-bromopropane on the female reproductive function in Sprague-Dawley rats. Industrial Health 35:278–284.

27. Yu IJ, Chung YH, Lim CH, Maeng SH, Lee JY, Kim HY, Lee SJ, Kim CH, Kim TG, Park JS, Moon YH

[1997]. Reproductive toxicity of 2-bromopropane in Sprague-Dawley rats. Scand J Work Environ

Health 23:281–288.

28. Ichihara G, Asaeda N, Kumazawa T, Tagawa Y, Kamajima M, Yu X, Kondo H, Nakajima T, Kitoh J,

Yu IJ, Moon YH, Hisanaga N, Takeuchi Y [1997]. Testicular and hematopoietic toxicity of 2-bromopropane,

a substitute for ozone layer-depleting chlorofluorocarbons. J Occup Health 39:57–63.
Page 40 Health Hazard Evaluation Report No. 98-0153-2883

29. Yu X, Ichihara G, Xie Z, Shibata E, Kamijima M, Asaeda N, Hisanaga N, Takeuchi Y [1999]. Effect

of inhalation exposure to 2-bromopropane on the nervous system in rats. Toxicology 135:87–93.

30. Kim HY, Chung YH, Yi KH, Kim JG, Yu IJ [1996]. LC50 of 2-bromopropane. Industrial

Health 34:403–407.

31. Ichihara G, Ding X, Yu X, Wu X, Kamijima M, Peng S, Jiang X, Takeuchi Y [1999]. Occupational

health survey on workers exposed to 2-bromopropane at low concentrations. Am J Ind Med 35:523–531.

32. Kawai T, Takeuchi Y, Moriyama Y, Sakamoto K, Zhang ZW, Higashikawa K, Ikeda M [2001].

Biological monitoring of occupational exposure to 1-bromopropane by means of urinalysis for

1-bromopropane and bromide ion. Biomarkers 6(5):303–312.