# 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 #2000-0410-2891 STN Cushion Company Thomasville, North Carolina

August 2002 This Heal t h Ha z ard E v alua t ion ( H H E ) report and any r e c o m m end a t i ons m ade herein are f or t he s p e c i f ic f a c ili t y e v alua t ed and may not b e un i ver s a ll y app li c ab l e. A ny re c o mm enda t i o n s m ade are n o t t o be c ons i dered as f i nal s t a t e m e n t s of N I O S H po l i c y or of any agen c y or i nd i v i d u al i nvo l v ed.

Additional HHE repor t s are ava il ab l e at h t t p : / / ww w

. c d c

. gov / n i o s h / hhe / repor t s

This Heal t h Ha z ard E v alua t ion ( H H E ) report and any r e c o m m end a t i ons m ade herein are f or t he s p e c i f ic f a c ili t y e v alua t ed and may not b e un i ver s a ll y app li c ab l e. A ny re c o mm enda t i o n s m ade are n o t t o be c ons i dered as f i nal s t a t e m e n t s of N I O S H po l i c y or of any agen c y or i nd i v i d u al i nvo l v ed.

Additional HHE repor t s are ava il ab l e at h t t p : / / ww w

. c d c

. gov / n i o s h / hhe / repor t s This Heal t h Ha z ard E v alua t ion ( H H E ) report and any r e c o m m end a t i ons m ade herein are f or t he s p e c i f ic f a c ili t y e v alua t ed and may not b e un i ver s a ll y app li c ab l e. A ny re c o mm enda t i o n s m ade are n o t t o be c ons i dered as f i nal s t a t e m e n t s of N I O S H po l i c y or of any agen c y or i nd i v i d u al i nvo l v ed.

Additional HHE repor t s are ava il ab l e at h t t p : / / ww w

. c d c

. gov / n i o s h / hhe / repor t s

This Heal t h Ha z ard E v alua t ion ( H H E ) report and any r e c o m m end a t i ons m ade herein are f or t he s p e c i f ic f a c ili t y e v alua t ed and may not b e un i ver s a ll y app li c ab l e. A ny re c o mm enda t i o n s m ade are n o t t o be c ons i dered as f i nal s t a t e m e n t s of N I O S H po l i c y or of any agen c y or i nd i v i d u al i nvo l v ed.

This Heal t h Ha z ard E v alua t ion ( H H E ) report and any r e c o m m end a t i ons m ade herein are f or t he s p e c i f ic f a c ili t y e v alua t ed and may not b e un i ver s a ll y app li c ab l e. A ny re c o mm enda t i o n s m ade are n o t t o be c ons i dered as f i nal s t a t e m e n t s of N I O S H po l i c y or of any agen c y or i nd i v i d u al i nvo l v ed.

Additional HHE repor t s are ava il ab l e at h t t p : / / ww w

. c d c

. gov / n i o s h / hhe / repor t s

app li c ab l e. A ny re c o mm enda t i o n s m ade are n o t t o be c ons i dered as f i nal s t a t e m e n t s of N I O S H po l i c y or of any agen c y or i nd i v i d u al i nvo l v ed.

Additional HHE repor t s are ava il ab l e at h t t p : / / ww w

. c d c

. gov / n i o s h / hhe / repor t sii 

# P REFACE

The Hazard Evaluations and Technical Assistance Branch (HETAB) of the Nati o nal 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, fo llowing 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.

H ETAB also provides, upon request, technical and consultative assistance to Federal, State, and loc a l 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.



# A CKNOWLEDGMENTS AND 

# A VAILABILITY OF 

# R EPORT

This report was prepared by Josh Harney, Jeffery Hess, and Doug Trout of HETAB, Division of Surveillance,
Hazard Evaluations and Field Studies (DSHEFS). Field assistance was provided by Chris Reh, Vince Mortimer, Calvin Cook, Ann Krake, Amber Rogers, Kristin Gwin, Barbara Mackenzie, Edward Hitchcock,
and James Kesner. Analytical support was provided by Datachem Laboratories. Desktop publishing was performed by David Butler. Review and preparation for printing were performed by Penny Arthur.

Copies of this report have been sent to employee and management representatives at STN Cushion Co. 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 th e 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 em ployees for a period of 30 calendar days.iii



## Highlights of the NIOSH Health Hazard Evaluation

a

a 

## Health Study of Workers Exposed to Bromopropane at STN Cushion

Company, Thomasville, North Carolina

NIOSH got a confidential request fro m workers worried about nerve problems, weakness, dizziness, leg numbness, and headaches they thought were from glue chemicals.



### What NIOSH Did

# We measure d air concentrations of 1-bromopropane (1-BP) and 2-bromopropane (2-BP) in the Fabrication area and in other areas of the plant.

# We checked the exhaust ventilation in the Fabrication area before and after improvements were made to the spray tables.

# We did a medical survey that included a questionnaire, blood and urine testing, neurobehavioral testing, and a female reproductive health study.



### What NIOSH Found

# Air concent r ations of 1-BP and 2-BP decreased in the Fabrication area by almost 2/3 after the ventilation improvements were made.

# Workers in the Fabrication area reported dizziness and blurred vision more frequently than those in other areas.

# Worker urinary bromine levels corresponded with the airborne 1-BP concentrations.

# We could not tell if the exposures to 1-BP at STN were related to health problems among employees. 

### What STN Managers Can Do

# Purchase only 1-BP based solvent containing the lowest possible amount of 2-BP (which is present as a contaminant).

# Decrease unused space in each spray booth to make the ventilation work as well as it can.

# Keep the Fabricatio n room emergency exit door and Poly room garage door closed when spraying glue.

# Provide g loves [not latex] that protect the skin of Sprayers from 1- & 2-BP.

# Change work practices so that employees are not allowed to eat or drink at their workstations.

# Share information on potential hazards of working with 1- & 2-BP to all workers who can be exposed.



### What STN Employees Can Do

# Participate in all ha z ard communication sessions.

# Wear the correct gloves when spraying glue.

# Wash hands before eating, drinking, or smoking, and at the end of the day.

# Do not eat or drink at your workstation.

# If you have health effects that might be related to the workplace you shou ld see a doctor experienced in occupational health issues.

Highlights of the HHE Reportiv 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 #2000-0410-2891 

## Health Hazard Evaluation Report 2000-0410-2891

STN Cushion Company Thomasville, North Carolina August 2002

Joshua M. Harney, MS Jeff Hess, MD Christopher Reh, Ph. D., CIH Doug Trout, MD, MHS



# S UMMARY

On August 28, 2000, the National Institute for Occupational Safety and Health (NIOSH) received a

co nfidential request for a health hazard evaluation (HHE) at STN Cushion Company (STN) in Thomasville,
North Carolina. The request was submitted by employees concerned about health effects potentially associated with 1-bromopropane (1-BP

, also called n-propyl bromide) and 2-bromopropane (2-BP , also called isopropyl bromide) exposures during the spray application of an adhesive. The employees’ concerns centered
around neuropathy (abnormal nerve function), weakness and numbness i n the lower extremities, dizziness,
and headaches.

Site visits were conducted in Nov ember 2000 (exposure monitoring and informal [confidential] employee interviews), April 2001 (ventilation assessment), a nd July-August 2001 (medical evaluation and repeat

exposure and ventilation ev aluations). After April 2001, STN improved the local ventilation in the area of

concern based on recommendations made by t he NIOSH ventilation engineer . During both exposure

assessments, employees were monitored for full-shift 1-BP and 2-BP inhalation exposu re. Short-term (15- minute) and ce iling (5-minute) 1-BP and 2-BP inhalation exposure measurements were also collected from
the adhesive sprayers (Sprayers). Area air sampling for 1-BP and 2-BP was conducted also. The ventilation

assessments included an evaluation of local exhaust ventilation at the workstations (consisting of spray tables and spray booths).

The medical survey , consisting of a questionnaire, a complete blood count, start -of-week and end-of -week urine analysis for bromine, and a battery of neurobehavioral tests, was performed on all employees within the facility who were willing to participate. Additionally , a reproductive study was performed which included all eligible female employees who were wil ling to participate. The purpose of the medical survey was: 1) to

assess whether hematological (blood), neurobehavioral (postural s t ability and psychomotor ability), and reproductive effects might be associated with 1-BP exposure; 2) t o assess whether health effects reported

on the questionnaire were associated with 1-BP exposure; and 3) to evaluate urinary bromine levels at thev

st art and end of the week and compare these results to airborne 1-BP levels (to see if urinary bromine
concentration can be used as a biomarker of exposure). The “exposed” population consisted primarily of
those employees who worked in the Fabrication area performing spraying activities. The comparison (“less exposed”) population consisted of all other employees who worked in the facility

.

At the first site visit the mean (average) airborne 1-BP exposure for the Sprayers was 65.9 parts per million (ppm) (r a nge 41.3 to 143.0 ppm). The mean full-shift airborne 2-BP exposure for Sprayers was 0.66 ppm (range 0.33 to 1.35 ppm). At the second site visit, the mean concentration of 1-BP for the Sprayers increased from the first (16.6 ppm) to the third (23.3 ppm) day of sampling, but was lower than the concentration found during the first site visit. T w o individual spray booths (Stations #6 and #1 1) did, however

, yield a 3-day

average exposure above a recommended level of 25 ppm. The initial ventilation assessment revealed that
all of the workstations had exhaust flow rates which were lower than recommended values. Enclosure of

spray tables led to improved ventilation at each of the workstations; however

, factors were identi f ied which would lead to further improvement in ventilation effectiveness.

Of the 84 individuals employed at STN at the tim e of the survey , 32 (38%) volunteered to participate in the
medical survey

. The symptoms most often reported from all participants included: headache (reported by 48%), trouble falling asleep or staying asleep (reported by 28%), dizziness or feeling “off balance” (reported by 25%), and blurred vision (reported by 24%). T wo of the symptoms in the questionnaire, blurred vision and dizziness or feeling “off-balance,” were significantly more common among the exposed versus the comparison groups. Of the exposed employees, five of six reporting blurry vision and four of six reporting dizziness noted symptom improvement during time away from the work environment.

All of the results for blood indices were within the normal value ranges provide d by the testing laboratory;
however , because of the small number of blood specimens available for analysis, a statistical determination regarding the blood tests and their relationship to 1-BP exposure could not be made. The start-of-week and
end-of-week urine bromine concentrations for the exposed group were both significantly higher than the corresponding values for the comparison group. W e found no significant elevation in urine bromine level in
the end-of

-week urine samples compared to the start-of-week urine samples—in other words, we did not
detect an increase in urine bromine from the first urine sample (start-of-week) to the secon d urine sample (end-of-week). Urinary bromine concentrations were highly correlated to the airborne concentration of 1-BP

, and it was concluded that urinary bromine may be a good indicator of 1-BP expo sure. A total of 30 participants participated in the neurobehavioral testing. W e found no differences in the Postural Stability test
results between employees in the exposed and com parison groups. Of the 16 Psychomotor Ability
parameters tested, 3 demonstrated a statistically significant differe nce between the exposed and comparison groups. Specifically , we found indications of increased tremor in the right hand of participants in the exposed

group. Although we cannot determine the cause of the tremor observed by our testing, we believe that this
unilateral tremor is likely due to muscle fatigue (a known cause of the type of tremor observed), as 1-BP

exposure, if sufficient to cause tremor , would likely cause bilateral tremor (tremor on both sides) due to a potential mechanism involving the central nervous sy stem. And lastly , we collected insufficient data among exposed workers in the rep roductive evaluation part of the survey to be able to make any comparisons between exposed and comparison workers in that portion of the HHE.

Although we found the Sprayers at STN to have greater exposure to 1-BP than other employees, we ar e unable to determine if these exposures constitute a health hazard. By enclosing the spray booths in the
Fabrication area, STN has dramatically reduced Sprayers’ exposure s to 1-BP and 2-BP . Because ofvi

symptoms consistent with excessive solvent exposure reported among the exposed workers, concerns raised

in other studies, a nd the lack of definitive information, efforts should continue to minimize 1-BP and 2-BP exposures. Recommendations are provided in this report to assist in this, and include improving the ventilation of spray booths #6 and #1 1 as well as improving personal protective equipment use.

Keywords: SIC Code 2392 (Ho use furnishing, Except Curtains and Draperies); 1-bromopropane, 1-BP

, 2-bromopropane, 2-BP , solvent, neuropathy , neurobehavioral, reproductive.

# T ABLE OF 

# C ONTENTS

Preface

....................................................................... ii

Acknowledgments and A vailability of Report

............................................. ii

Summary

.................................................................... iv

Introduction

................................................................... 1

Background

.................................................................... 1

Methods

...................................................................... 1 Air Sampling

................................................................ 1

V entilation Assessment

......................................................... 2 Medical Survey

.............................................................. 3 Survey Population

......................................................... 3 Questionnaire

............................................................ 3
Blood

.................................................................. 4
Urine

.................................................................. 4
Neurobehavioral T

esting

..................................................... 4 Postural Stability

....................................................... 4 Psychomotor Ability

.................................................... 5 Reproductive Study

........................................................ 5 Statistical Analysis

......................................................... 6

Evaluation Criteria

............................................................... 6 1-Bromopropane and 2-Bromopropane

.............................................. 7
Local Exhaust V

entilation

....................................................... 7

Results

....................................................................... 8 Air Sampling

................................................................ 8 November 2000—before enclosure of spray tables

.................................. 8 July/August 2001—after enclosure of spray tables

................................... 9
Local Exhaust V

entilation

....................................................... 9 Spray T able Evaluation— November 2000—before enclosure of spray tables

................ 9 Spray Booth Evaluation— July/August 2001—after enclosure of spray tables

............... 10 Medical Survey

............................................................. 10 Questionnaire

........................................................... 10
Blood

................................................................. 10
Urine

................................................................. 1 1
Neurobehavioral T

esting

................................................... 1 1 Postural Stability T

esting

................................................. 1 1 Psychomotor Ability T

esting

.............................................. 1 1 Reproductive Evaluation

.................................................... 12

Discussion

................................................................... 12 Exposure Survey

............................................................ 12viii

V entilation Assessment

........................................................ 12 Medical Survey

............................................................. 13 Questionnaire

........................................................... 13 Hematological Effects

...................................................... 13 Urinary Bromine

......................................................... 13
Neurobehavioral

......................................................... 14 Psychomotor Ability T

esting

.............................................. 14 Postural Stability T

esting

................................................. 14 Survey Limitations

........................................................... 14

Conclusions

.................................................................. 15

Recommendations

.............................................................. 15

References

................................................................... 15

T ables

....................................................................... 19

Appendix

.................................................................... 34Health Hazard Evaluation Report No.2000-0410-2891 Page 1



# I NTRODUCTION

On August 28, 2000, the Nation al Institute for Occupational

Safety and Health (NIOSH)
received a confidential request for a hea l th hazard

ev aluation (HHE) at STN Cushion Company ( STN) in Thomasville, North Carolina. The

r equest was submitted by employees concern e d
about healt h effects potentially associated with 1- bromopropane (1-BP

, also c alled n-propyl bromide) and 2-bromopropane (2-BP , or isopropyl bromide) exposures during the spray application of

an adhesive. The employees’ concerns included

n europathy (abnormal nerve function), weakne s s and numbness in the lower extremiti es, dizziness,
and headaches. On November 14, 2000, NIOSH investigators conducted an initial site visi t at STN
which incl

u ded an exposure assessment of employees applying the adhesive and informal (confidential) interviews to learn more about employee health concerns. A NIOSH ventilation engineer asses s ed the performance of the existing
local exhaust ventil a tion (LEV) in the Fabrication

area on Apr

il 18, 2001. Based on
recommendat ions made by NIOSH following the April site visit, STN en closed the spray tables on four sides to improve the capture efficiency of the
local exhaust ventilation, thus creating ‘spray
booths.’ On July 31 to August 2, 2001, NIOSH
conducted follow-up exposu re monitoring,
ventilation as s essment, and medical evaluations of
workers.

In January 2002, each study participant was sent

a copy of all personal test results from the medical
evaluation. Results of the industrial hygiene sampling were initially sent to STN and an employee representative in letters dated February 21, 2001 (for the sampling conducted in November 2000), and September 12 , 2001 (for sampling
conducted July-August 2001). A letter containing

a preliminar y analysis of the data (including data
from biologic samples, neurobehavioral testing, and
the ques tionnaire) was distributed on May 24, 2002. This report consolidates all previous communication, and includes up-to-date
conclusions and recommendations. 

# B ACKGROUND

STN manufactures sof a cushions for various
furniture companies. Each cushion is assembled
b y gluing together several pieces of cut flexible
foam. Once two pieces of foam are glued together

, they are

hand-pressed to achieve a

proper bond. The adhesive is spray-applied using

a compressed air spray gun in the Fabr ication

room. This room initially contained 13 spray stations having a slotted LEV hood and one downdraft spray table. Following the LEV improvements, the downdraft spray table was discarded, and only 12 spray sta tions were used.
The adhe sive is Whisper Spray (Imperial Adhesives, Cincinnati, Ohio), which contains 55% by weight 1-BP . This product also contains 1–5% VM&P naphtha and 1–5% ethyl acetate. In addition, small amounts of 2-BP are usually
present in most 1-BP-containing formulations.
Occasion ally , a water-based spray adhesive (Simalfa® 309, Alfa Adhesi v es, Inc., North Haledon, Ne w Jersey) that contains no hydrocarbon solvent is used at up to four spray stations. Adjacent to the Fabrication room are the
Saw room and the Poly room, neither of which use the spray adhesive.



# M ETHODS

Air Sampling

During the November 2000 exposure assessmen t

, employees in the Fabrication room were monitored
for full-shift inhalation exposures to 1- and 2-BP
inhalation exposure . Short-term (15-minute) and ceiling (5-minute) 1-BP and 2-BP inhal ation

exposure measur ements were also collected from
the Sprayers. In addition, area air sampling for 1-
and 2-BP was conducted in the Fabrication, Saw

,Page 2 Health Hazard Evaluation Report No.2000-0410-2891

and Poly rooms to de termine the degree of vapor migration away from the spray tables. For the
inhalation exposure measurements, the sampling

pumps and sample train s were worn by the employees, and the sample media were placed in the subjects’ breathing zones. Air sampling was conducted using a NIOSH draft sampling and 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 50–250 millili ters

per minute using a calibrated personal sampling

pump. After sampling, the charcoal tubes are

c apped and shipped refrigerated to the analytical laboratory

. The front and back sections of the
charcoal tubes are placed in glass vials, and each
section is desorbed for 30 minutes with 1 milliliter
of carbon disulfide. Each sample is 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 ) were 0.001 milligram per sample (mg/sample) and 0.004 mg/sampl e , respectively

. The LOD and LOQ for 2-BP are

0.001 and 0.00 3 mg/sample, respectively . LODs
and LOQs are values determined by the analytical

proc e dure 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 t he given set of samples. For this HHE, the average sample
volume for a given set of samples was used to
calculate these values. MDCs and MQCs for the
full-shift exposure measurements can be found at
the bottom of T able 1, for the short-term exposure

measurements at th e bottom of T a ble 2, for the ceiling exposure measurements at the bottom of

T able 3, and for the area ai r sampling at the
bottom of T

a ble 4. While the LODs and LOQs
are listed above in terms of mg/sample, the MDCs
and MQCs in the tables have been conv erted to parts per million (ppm) to be consistent with the
evaluation criterion.

During the second exposure assessment, full-shift,
short -term, and ceiling personal breathing zone (PBZ) samp les were again collected from Sprayers. The 1-BP LOD and LOQ for the analytical method used were 0.0007 mg/sample
and 0.002 mg/sample, respect ively . The LOD
and LOQ for 2-BP were 0.0006 and 0.002 mg/sample, respectively

. MDCs and MQCs for full-shift, short-term, and ceiling ex p osure

meas u rements from this portion of exposure monitoring can be found at the bottom of t h eir respective tables (T

ables 5, 6, 7) at the end of this
report.



## V entilation Assessment

The LEV at the Sprayer’s worksta tions was
assessed both before and after the enclosure of
the s pray tables into spray booths. For the

purposes of this report, the spray stations in the
Fabrication area will

be referred to by a

n umbering system. As one walks through the plastic curtain from the Saw room into Fabrication
and turns to face the wall on the right, Station #1 is the rightmost workstation (nearest the lavatory).
Station #2 is immediately to the left of Station #1,

a nd shares its spray booth. Numbering then proceeds with Station #3, immediately to the right
of Station #4. Station #4 is to the right of the exit
door

. Station #5 is on the left side of this exit
door , followed in a row along the wall by Stations

#6 through #12. At the end of the Fabrication

room directly opposite Stations #1 an d #2 is Station #12, next to the doorway to the Poly room.

T w o work- stations that were present durin g the
November 2000 survey were not durin g the July/August 2001 surv ey (the downdraft spray table, and a booth along the wall between the Fabrication room door and the lavatory).

Air v elocity into the LEV plena was measured
with a hot

- wire anemometer (TSI® V elocicalcHealth Hazard Evaluation Report No.2000-0410-2891 Page 3

Plus, model #8360) during both evalu ations. During the November 2 000 evaluation, five
velocities were recorded for each slot, giving 2 0 readings for each slot

hood. Three rows of four

meas urement points were used for the downdraft table, and 128 readings for each double-station
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 m e asured at 6-inch
intervals out from the back wall of the workstat i on. Some groups of measurements were
taken more t han once, and the readings were averaged to give one set of values.

The movement of air w as also observed using
“smoke tu bes” (MSA #458481, Mine Safety Appliances Company

, P ittsburgh, Pennsylvania).
The direction o f air movement between the inside
and the outside of the building was observed using

a smoke tube. The “smoke” was released at the
bottom of the door

, and observed to note whether
it was drawn out of the building or blown in across
the floor

. If the door was sealed at the bottom to restrict air infiltration, the door was opened slightly to check air flow along the edge.

After the April 20 01 site visit, the spray tables

were enclosed t o become spray booths; each
station had its own s pray booth, except for #1 &

#2 and #9 & #10, which shared spr ay booths.

Measurements of the spray b ooths were made during the July/August 2001 evaluation. T w o of
the spray booths (at Station s #3 and #6) are 8' x

44" x 46". Six booths are 10' x 44" x 45"(Station #4, #5, #7, #8, #1 1, #12). T w o spray booths are large enough to accommodate two spray Sta tions each (#1 & #2, and #9 & #10): 14' x 43" x 45". A
thermo a nemometer was used to measure the face velocity at evenly distributed points across the mouth of each spray booth where the Sprayer
would normally stand. Measurements were collected under two different conditions: ‘doors open’ and ‘doors closed.’ This refers either to
both the Poly room garage door and Fabrication

room outdoor exit door being open or both being
closed. These measurements were combined to yield the average face velocity for each spray
booth.



## Medical Survey

The medical survey , consisting of a questionnaire,

a complete blood cou nt, pre- and post-exposure
urine analysis for bromine, and a batter y of
neurobehavioral tests was performed on all emplo yees within the facility who were willing to participate. Additionally , a reproductive study was performed and included all female employees who

were willing to participate. The purpose of the
medical survey portion of this HHE was: 1) to

a ssess whether objective evidence for hematological (blood), neurobehavior al, and reproductive adverse effects were associated with

1-BP exposure; 2) to assess w hether adverse
health effects reported on the questionnaire were associated with 1-BP exposure; and 3) to evaluate urinary bromin e levels of employees and comparePage 4 Health Hazard Evaluation Report No.2000-0410-2891

these results to airborne 1-BP levels (to see if urinary bromine concentration can be used as a
biomarker of exposure). The survey was

appr oved by the NIOSH Human Subjects Review
Board and was conducted over a three-day period beginning on Monda y , July 31, 2001. All employees working at the facility were given the opportunity to enroll in the survey following a 15-
minute presentation conducted at STN by NIOSH representatives in the week prior to the survey . In
that presentation, the purpose of the study , the

tests that would be pe rformed, and the risks and
benefits of pa

rticipation were discussed. Following the presentation, each empl o yee was given the opportunity to enroll in all, portions of, or none of the study . Informed consent was obtained from each employee choosing to participate.



## Survey Population

For this survey , the “exposed” population
consisted of those employees who worked as Fabrication Sprayers for any part of their work

s hift, and employees who performed activiti e s other than spraying in the Fabrication area for at
least one half of their typical work shi ft. The comparison (“less exposed”) population consisted
of all other e mployees who worked in the facility
and who did not perfo rm activities in the Fabrication area or who performed non-spraying
activities in the fabricat ion area for less than one half of their typical work shift.



## Questionnaire

On August 1, 2001, each participant was asked to complete a questionnaire. The questionnaire
included questions concer ning demographic
factors (age, gender

, etc.), job factors, medical and work history

, non-occupational exposures, and
symptoms. The questionnaire was selfadministered and a NIOSH staff member was available to explain the q uestions, define medical terms for participants, and check the questionnaire for completeness and errors. For evaluation of the quest i onnaire, positive responses were determined by a “yes” or “unsure” response to any question. Negative responses were determined by a “no”

response.



## Blood

Blood samples were analyzed for blood cell counts
because the medical literature has suggested that

exposure to brominated solvents may be
associated with pancytope nia (a decrease in the number of all blood cell types). A 6-milliliter blood sample was collected from each participant during
the afternoon of August 2, 2001. V e nipuncture

was performed by a trained technician following
univ ersal precautions for working with blood and
blood products. 1 After venipuncture, blood

s amples were placed on ice and shipped to the

NIOSH contract laboratory for analysis. Analysis
consisted of determining the white bl ood cell (WBC) count, red blood cell (R BC) count, and platelet cell (PC) count of each sp ecimen. The

counts of these cell types were compared between the exposed and comparison groups.



## Urine

Urine spec i mens were collected early in the morning of July 31 (prior to the work shift—“starto f-week” sample) and in the afternoon of Aug ust 2, 2001 (at the end of the work shift— “end-ofweek” sample). After collection, urine samples

were frozen, stored on ice, and shipped to the

NIOSH contract laboratory for analysis. Analysis
consisted of measuring the bromine and creatinine concentration of each specimen. At present, there
is not an established normal range for the
concentration of bromine i n human urine and so
values obt ained were compared between the exposed and comparison groups.

For the purposes of this HHE, pre- or postexposure urine specimens with a creatinine value
outside of the acceptable range (c r eatinine less
than 0.3 grams/liter [g/L] or greater than 3.0 g/L)Health Hazard Evaluation Report No.2000-0410-2891 Page 5

were not reported or used for analysis, because they cannot be relied upon to accu r ately reflect
the true body burden of bromine. 2 Urinary
bromine levels were no t corrected for creatinine
concentration. Start-of-week urine bromine
concentrations were compared to end-of-w eek
concentrations so that the c hange over the 3-day period could be determined.



## Neurobehavioral T

esting

Neurobehavioral testing measures basic psychophysiological functions (alert ness, reaction time,

memory , tremor

, sensory and motor performance).

T wo neurobehavio ral test types (Postural Stability and Psychomotor Ability) were used in this survey

to evaluate the presence of neurologic changes potentially related to 1-BP exposure . Other
researchers have used these or similar tests to
evaluate n eurologic changes due to solvent

exposure. 3 ,4,5,6 Neurobehavioral testing was
chosen over electromyography (tests of individual
muscle function) because it was felt to be a more sensitive mea sure of neurological change. Analysis of each

test parameter , comparing

expo s ed and comparison groups, was performed

to determine if a signif i cant difference exists
between the group’s performance (between-group analysis).

Postural Stability

Each participant was tested on a micro computercontrolled force platform usi ng protocols
established by NIOSH and the University of
Cincinnati. 7

, 8

, 9

, 10 T e st conditions were designed to

t est the three main afferents (variables) responsible for maintaining post u ral stability (e.g., vision, vestibular perception, and proprioception).
After one practice trial, each participant was asked to s tand on the force platform while performin g each of six different postural

ma neuvers lasting 30 seconds. For the first

maneuver , participants were instructed to remove

t heir shoes and stand still on the platform wi t h arms at their sides focusing on a fixed mark on the

wall directly in front of them. The next maneuver required the participant to maintain the same posture but with their eyes closed. These two test

maneuver s were then repeated while the participant stood on a 4-inch thick foam pad. The
final two test maneuvers required the participant to stand still on one leg with eyes open, but

f ocusing on the fixed mark on the wall was n o t required. This maneuver was then repeated while standing on the opposite leg. Sway area and sway length were measured during each test. Sway

area represents the area within the sway path in

square centimeters, and sway length is the length of the sway path in centimeters.

Psychomotor Ability

A commercially available test system (CA TSYS ® )
from Danish Product Development was used to

test psychomotor ability

. 11 Eight tests were
selected to evaluate arm-hand tremor

, simp l e reaction time, and rhythmic finger/hand tapping ability

. T est procedures and device characteristics

are described in a previous NIOSH publication. 1 2

The test researcher explaine d and demonstrated
each test to the participant before allowing the
individual to perform that test. Participants were
allowed to repeat a test onl y if they did not start
the test within 5 seconds of whe n the equipment

was activated and the rese archer indicated the

s ubject should begin, or the computer determin e d
that there were insufficient responses dur ing the

test period to calculate an accurate test result. The system had a volume control which was set to
maximum volume so that any subject with hearing
difficulties could clearly hear the audible “clicks” produced for certain tests.

Tremor was measured using a tre mor pen. Each subject held the pen first in the right hand and then

in the l eft hand (referred to as tremor pen right
and tremor pen left), similar to an ordinary pencil,

in front of their chest with their elbow be n t at 90 degrees, and the forearm away f rom their bodyPage 6 Health Hazard Evaluation Report No.2000-0410-2891

for a prescribed period of time while the equipment recorded movements of the pen. Each
hand was tested twice with re sults from the
second test retained for da ta analysis. Tremor intensity (i.e., amplitude), the root-mean square of
accelerations re corded in the 0.9 Hertz (Hz) to

15.0 Hz band during a 16-sec o nd test, and center
f requency (i.e., average frequency of
accelerations at the mid-point of the energy band)

were the p r incipal measurements used for analysis.

Simple auditory reaction time was assess ed via a
hand-held thumb swi

tch (referred to as reaction time). The participant was instructed to hold the switch in his or her dominant hand and press the
thumb switch every time he or she heard the
system produce an audible ‘cli ck.’ The test
computer produced each ‘click’ at random
intervals for a total of 30 seconds. Mean response latency (milliseconds) is the measurement used for analysis.

The rhythmic finger tapp ing was assessed via a
sho ck sensor . Each participant was instructed to
use his or her dominant hand for the test. The palmar surface of

the wrist rested on the table
surface in front of the shock sens or and the

p articipant was instructed not to elevate the wri s t
off the ta ble surface during the test. When the

test began th e participant was to tap their index finger on the se n sor once for each audible ‘click’ produced by the test computer . The first test used

a long interval be tween each ‘click’ (referred to

as slow rhythmic frequency f inger tap). The
second tes t used a short interval between each
‘click’ (r e ferred to as fast rhythmic frequency finger tap). The last test used a crescendo, decreasing interval, between each ‘click’ (referred

to as maximum frequency finger tap). Rhythmic
hand tapping was assessed using the same sensor

. The participant was instructed to tap their
dominant hand on the sensor alter nately using the supinated (hand extended with palm surface up)
then pronated (hand extended with palm surface down) surface of their dominant hand with each
‘click’ produced by the test computer . The first

test used a long interval be tween each ‘click’ (referred to as slow pronation/supination rhythmic frequency). The second test used a crescendo, decreasing interval, between each ‘click’ (referred

to as maximum frequency pronation/supinat ion).



## Reproductive Study

The reprod uctive portion of this HHE was designe d to evaluate changes in women’s
hormonal cycle that might be related to 1-BP

exposure. A reproductive study of males was not
conducted at STN primarily because there is only

one male employee considered “exposed” at STN.
The s tudy included a questionnaire, first morning
urine samples (5–10 mill iliters) collected daily for

one complete menstrual cycle (or

, in the event of amenorrhea, for at least 42 days), and dai ly diary documentation during the urine collection phase.
The questionnaire for this portion of the study
included questions pri marily pertaining to

repr oductive health history . Urine samples were

an alyzed (at the NIOSH Reproductive Endocrinology Laboratory) for luteinizing hormone (LH), follicle stimulating hormone (FS H), and the primary urinary metabolites of estrogen (estrone 3-glucuronide [E,3G]) and progesterone (pregnanediol 3-glucuronide [Pd3G]). The daily diary was used to document sample collection,

presence of menses, and use of medications or
birth control.

At the time that the q uestionnaire was
admin i stered, NIOSH investigators provided each participant with a collection kit and detailed verbal
and written inst

r uctions on the urine collection

process. Participants were instructed to store
urine samples in the ir own freezer (at home) during the collection process; vials contained 7% glycerol to p revent freeze-induced activity loss of
LH and FSH.Health Hazard Evaluation Report No.2000-0410-2891 Page 7

W omen who volunteered in the female reproductive health portion of the study (Phase II) were paid $100 for participation.



## Statistical Analysis

Statistical analyses for this survey was performed using SPSS for W

indows Release 1 1.0.1 (SPSS Inc., Chicago, IL). A p-value of 0.05 and 95%
confidence intervals (95% CI) which excluded the
value one were used to determine statistic a l significance. The odds ratio (OR), a measure of
the strength of association betwee n reported
symptoms and expos u re, was used to evaluate questionnaire responses. The OR represents the
odds of an outcome in the “expose d” group
relative to the odds in the “unexposed” group. An

OR of one means there is no association between
the outcome and “exposure.” An OR of greater
than one indicates that there is eviden ce of an
association. For example, an OR of two would

mean th at a person in the “exposed” group may
have two times the odds of reporting the outcome than a person in the “unexposed” group.



# E V ALUA TION 

# C RITERIA

As a guide to the evaluation o f the hazards posed by workplace exposures, NIOSH field s taff 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 lifetim e without experiencing
adverse he alth effects. It is, however , important

to note that not all workers will be protected from
adverse health e ffects even though their

exposures are maintai

ned below these levels. A
small percen tage may experience adverse health
effects becaus e of individual susceptibility , a preexisting medical condition, and/or a hypersensitivity (al

lergy). In addition, some hazardous substances may act in combination with other workpl ace exposures, the general environment, or with medications o r personal
habits of the worker to produce health effects

even if the occupational exposures are controlled

at the level set by the criterion. These combined
effects are often not considered i n the evaluation
criteria. Also, some substances are absorbed by
direct contact with the skin and mucous membranes, an d thus potentially increases the
overall exposure. Finally , evaluation criteria may change over the yea

rs as new information on the toxic effects of an agent become available.

The primary sources of env i ronmental evaluation
criteria for the workplace are: (1) NIOSH

Reco mmended Exposure Limits (RELs), 1 3 (2) the

Amer i can Conference of Governmental Industrial Hygienists’ (ACGIH®) Threshold Li m it V alues (TL Vs®)

, 14 and (3) the U.S. Department of
Labor , Occupational Safety and Health
Administration (OSHA) Permissible Exposure
Limits (PELs). 15 Employers are encouraged to
follow the OSHA limits, the NIOSH REL s, the

ACGIH TL

V s, or whichever are the more protective criteria.

OSHA requires an employer to furnish employees

a place of emplo y ment 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)]. Thus, employers should understand that not all hazardous
chemicals have specific OSHA exposure limits
such as PELs and short-term exposure l imits (STELs). 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 (TW A) e xposure refers

to t he average airborne concentration of a substance during a normal 8- to 10-hour workday

. Some substances have recommended STEL or

ce i ling values which are intended to supplementPage 8 Health Hazard Evaluation Report No.2000-0410-2891

the TW A where there are recognized toxic effects from higher exposures over the short-term.



## 1-Bromoprop

ane and 2-Bromoprop

ane

Laboratory studies of the toxicology of 1-BP have
shown that excessive exposure of animals to 1-BP

can lead to reproductive and neurologic effects.
The limited published information concerning occupational exposure

to 1-BP suggests neurologic and reproductive effects in humans. A
review of the scientific literature relevant to occupational ex posure to 1-BP is presented in the Appendix.

Currently

, there are no NIOSH, ACGIH, or

OSHA exposur e evaluation criteria for 1-BP

. Albemarle Corporation (a manufacturer of 1-BP)
has recommended an occupational exposure guideline for 1-BP

, based on the initial, unaudited
data from a two-generati on reproductive study in

rats. 16 In that study , young male and female rats
received a d a ily 6-hour inhalation exposure to a known concentration of 1-BP for a minimum of 70 days. After this period, the animals were paired
for mating, and the daily exposures continued through the 14-day mating period, and through day

20 of gestation. No litters were observed in the

750 parts per million (ppm) exposure group, and a significan t decrease was observed in the number
and size of litters in the 500 ppm exposure group. A slight (insi

gnificant) decrease was observed in
the mean number of pups born and l ive pups per
litter for the 250 ppm exposure group. Based on
these results and a 10-fold safety factor

, Albemarle set t heir 1-BP recommended exposure guideline at 25 ppm as an 8-hour TW A

exposure. 17

The South Korea Ministry of Labor is the o nly
government agency to develop an occu pational

exposure l

evel (OEL) for 2-BP . In 1998, the Ministry issued a 2-BP OEL o f 1 ppm as an 8- hour TW A. 18 This standard is based on a limited number of workplace epidemiological studies and toxicological (animal) studies which found that 2-

BP exposure produces repro ductive effects in
both males (low sperm count) and females (ovarian dysfunction), and also affects the hematopoietic (blood forming)
system. 19

, 20

, 21

, 22

, 23

, 24

, 25



## Local Exhaust V

entilation

The velocity of air at any point in front of a hood

necessary to ov ercome opposing air currents and

to capture the contaminated air at that point by causing it to flow in to the hood is called the
captu re velocity

. 26 The velocity with which the
contaminant

is released and other factors will
determine the appropriate value for the capture velocity

. For the adhesive spraying operation at STN, the contaminant dispersion would at least be
characte r ized as “low velocity release into moderately still air ,” for wh ich the range of
recommended capture velocities is 100–200
ft/min. For some workstations, the contaminant dispersion might be better characterized as “active generation,” for which the range of recommended capture velocities is 200–500 ft/min. 27

The lower end of these ranges is acceptable when
the air currents at the point of capture are minimal or favorable to capture, the contaminant(s) is (are)
of lo w toxicity or of nuisance value only , the production rate is low or intermittent, or the hood is large enough to cover the work area and contain
the air mass moving toward the hood. However

, when distur b ing air currents are present, the contaminant(s) is (are) highly toxic, production
rates/contaminant

- source-substance usage is high
and/or the hood is small and capable of providing
local control only

, the uppe r end of the range is
recommended. 27

For the adhesive spraying operation at STN, although disturbing room air currents were not prevalent, neither w ere they minimal or favorableHealth Hazard Evaluation Report No.2000-0410-2891 Page 9

to capture. Although not classifiable as highly toxic, bromopropane toxicity is unknown (and was

not classified as low toxicity). Production was fairly steady , and the hood openings did not extend
the full width of the wor k stations. This indicates
that the c apture velocity should be at least 150
ft/min and, for some workstations, as high as 350
ft/min.

The captur e velocity at the furthest point of
contaminant release in front of a hood is related to the required exhaust air flow by the equation 28

Q = 0.75v(10x 2 + A)

Where: Q = the required exhaust air flow in cubic feet per minute (cfm)
v = the capture velocity in feet per minute (ft/min)

x = the distance i

n feet from the hood

f ace to the furthest point of contaminant
release
and A = the ho od face opening area in

square feet (ft 2 ). 29

The opening area is the width of the opening or slots multiplied by the distance from the bottom of
the lowe st slot or opening edge to the top of the highest slot or opening edge. 28

For the adhesive spraying op erations in front of
the back-draft hoods, the furthest point of
contaminant release would be app roximately 3 ft
in front of the back wall of the workstations. For either: 1) the single 26-inch wide opening (7 inches high), or 2) the four 30-inch wide slots (1 inch high, spaced 6 inches apart), the exhaust flow rate
should be at least 10,000 cubic feet per minute (CFM). For the down-draft table with a 21-inch long opening, 12 inches wide, the exhaust flow

rate at 18 inche s above the surface should be at
least 2700 CFM. 

# R ESUL TS

Air Sampling

November 2000—before enclosure of spray tables

A total of 14 full-shift 1-BP and 2-BP exposure
measurements were collected from workers in the
Fabrication room (T able 1). T w elve o f these measurements were from Sprayers, and two were fro m floaters. The mean (average) 1-BP air

con centration for the Sprayers was 65.9 ppm, ranging from 41.3 to 143.0 ppm. All 12 of the Sprayers ha d exposures which exceeded the
Alb emarle exposure guideline of 25 ppm. The 1-

BP concentrations for the two floaters were 8.7 and 19.4 ppm.

The mean full-shift 2-BP concentration for Sprayers was 0.66 ppm, ranging from 0.33 to 1.35

ppm. One of these concentrations exceeded the

Sou th Korean OEL of 1 ppm. The 2-BP
concentrations for the floaters were 0.19 and 0.28

ppm.

Random short

- term (15-minute) and ceiling (5- minute) exposure measurements were obtained in
order to characte r ize acute 1-BP and 2-BP

exposures in Sprayers. Nine short-term exposure

m easurements were obtained from Sprayer s (T able 2). The short-term 1-BP concentrations ranged from 33.7 to 173.9 ppm, and the short-term

2-BP concentrations ranged fr om 0.30 to 1.56

ppm.

Eleven ceiling exposure measure ments were also
obtained from the Spray ers (T a ble 3). The 1-BP ceiling concent rations ranged from 39.5 to 151.9

ppm, and the 2-BP concentrations ranged from 0.37 to 1.13 ppm.Page 10 Health Hazard Evaluation Report No.2000-0410-2891

Fina l ly

, full-shift area air sampling was conducted

in the Fabricati

on, Saw , and Poly rooms to
determine the 1-BP and 2-BP room concentrations, and to determine the extent to
which these compounds are migrating to adjace n t

areas. These data are shown in T a ble 4. The 1-

B P and 2-BP concentrations in the Fabrication

room were 7.2 and 0.1 1 ppm respectively . In addition, the 1- BP concentrations in the Saw and Poly rooms were 7.7 and 1.7 ppm, and the 2-BP
concentrations wer e 0.20 and 0.05 ppm respectively

.


## July/August 2001—after enclosure of spray tables

Cushion production reportedl y was slightly below normal at the beginning of this survey (July 31, 2001), but increased roughly 20% each of the next two days. Results from full-shift air sampling
done each day are listed in T able 5. The mean
concentration of 1-BP for the Sprayers increased
from the first (16.6 ppm) to the third (23.3 ppm) day of sam pling, but was lower than the
concentration found during t he first site visit; the mean 2-BP concentration did not vary widely

. For
each day of sampling, the mean concentration of
the Sprayers as a group was below the exposure

limi t suggested by Albemarle. T w o individual

spray booths (Stations #6 and #1 1 ) did, however

, yield a 3-day average exposure above 25 ppm for the workers at those particular booths.

T able 6 lists short-term (15 m inute) exposures of
the Sprayers. Concentrations for 1-BP ranged
from 0.2 ppm, for the Sprayer at booth #1 1, who did not spray much during this 15 minute period, to

56 ppm. 2-BP short-term concentrations ranged
from trace (between 0.04-0.13 ppm) to 0.4 ppm.

T able 7 lists the Sprayers’ 5-minute ceiling

exposures. Concentrations ranged from ‘not
detected’ (below 0.14 ppm) to 38 ppm f or 1-BP

, and from ‘not detected’ (below 0.12 ppm) to 0.5 ppm for 2-BP

. Air sampling results for non-Sprayers are listed in

T ab le 8. Several PBZ and general area (GA) samples we re collected each day . 1-BP
concentrations ranged from 0.01 ppm (GA samples collected outside the building) to 6.1 ppm (GA sample collected on the saw room I-beam
closest to the doorway to the assembly area). 2- BP concentrations were 0.1 ppm or less in all samples. These results indicate that at least some solvent vapor appears to be present in areas of the plant away from the Fabrication area.



## Local Exhaust V

entilation

Spray T able Evaluation—
November 2000—before enclosure of spray tables

The capture velocity 3 ft in front of the t h irteen
back-draft hoods i

n the Fabrication area ranged
from 6 ft/min to 73 ft/min, and the capture velocity
18 inches above the down-draft table (station # 6)

was 26 ft/min. (See T able 9) The calculated
exhaust flow rates for each hood (also listed in

T able 9) ranged from 230 CFM to 1545 CFM. All
of the values are less than th e recommended
val u es (as discussed in the Evaluation Criteria section).

Consistent with the low exhaust f l ow rates and
capture velocities, air-flow visualiza tion revealed
that the hoods performed only marginally well with air flowing toward the back of the workstations at some, but not all, locations across the face of each
work- station. Moreover , except for the hood with
the greatest air flow

, for which all smoke released

at the front edge of the workstation was “captured,” contaminants released at one (or both) edge(s) of each of the other workstations would
drift lazily away into the workroom. The external
foam filter covering some of the openings did not

seem to greatly affect the flow of air in front of
the hoods.Health Hazard Evaluation Report No.2000-0410-2891 Page 11

Observed work practi

ces revealed that pieces of
foam for seat cushions were stacked in front of
the slot hoods at some workstations, preventing
adhesive spraying in the region of the workstation
where e xhaust ventilation would be most
effective. Some large pieces blocked the local
exhaust ventilat

ion slots while being sprayed with adhesive, restricting the effectiveness of the local
exhaust ventilation.



## Spray Booth Evaluation— July/August 2001—after enclosure of spray tables

T able 10 shows the average capture velocity
measured at each spray booth under t wo sets of
conditions: ‘doors open’ and ‘ d oors closed.’ Capture velocities at the spray booths ranged from 18 ft/min (Station #12) to 70 ft/min (Stations #1 & #2) with the doo rs closed. Operating with the
doors closed did not h ave a clear effect on the
capture velocity of all the spray hoods compared to when the doors were open.



## Medical Survey

Questionnaire

Of the 84 individuals employed at STN at the time
of the survey , 32 (38%) volunteered to participate

in the medical survey

. A total of 30 (36% of the 84) employees completed the st u dy questionnaire;
included in this number were 12 (92%) of 13 employees in the exposed group, and 18 (25%) of

71 in the comparison group. T a ble 1 1 lists
sel e cted characteristics of participating employees
who completed the questionnaire. Of note, the employ ees in the groups were primarily women,
and were of similar age. Employees in the

e xposed group had a mean length of employm ent

at STN of 13 years, compared to 21 years for employees in the comparison group . T w o (17%)

in the exposed group and 7 (39%) in the comparison group provided positive answers to the question concerning exposure (occupationally or thro ugh other activities) to other substances of

concern (d efined in the questionnaire as arsenic,

mercury , lead, cadmium, solv ents, or pesticides).
The two su bjects from the exposed group responding posi

tively to this question had marked
“don’t know” as their response and did not give

any further detail concerning their exposure in the explanation section.

Regarding data collect e d concerning work practices, 92% of exposed wor kers responded they always wore some type of protective clothing (such as an apron) while working; our observation
of work practic e s revealed that the aprons worn did not protect the arms from cont act with
solvents. T

w o (17%) exposed an d 1 (6%) comparison subject responded that they smoked
“sometimes” or “rarely” in the work area. Sixteen
percent of

the exposed group washed their hands “always” or “sometimes” before smoking and
after performing work activities. All participants reported that they washed their ha nds before eating or chewing gum after pe rforming work
activities.

T able 12 presents data concerning reported
symptoms by expo sure status (exposed versus comparison group). The symptoms most often
report ed from all participants included: headache (reported by 48%), trouble falling asleep or staying asleep (reported by 28%), dizziness or feeling “off
balance” (reported by 25%), and bl urred vision (reported by 24%). The data in T a ble 12 reveal
that two of the symptoms in the questionnaire had

a statistically significant odds ratio bet ween the exposed and co mparison groups (indicating that
those t wo symptoms were reported more commonly among the exposed employees versu s the comparison group). The exposed group reported 16 times the odds of experiencing blurred
vision (95% CI 1.6

- 162), and 15 times the odds
of experiencing dizziness or a feeling of being “off
ba lance” (95% CI 1.5 - 153) within the last 30Page 12 Health Hazard Evaluation Report No.2000-0410-2891

days. None of the odds ratios for the remaining
symptoms were statisti

cally significantly elevated.
Of the ex posed employees, five of six reporting blurry vision and four of six reporting dizziness
noted symptom improvement during time away from the work environment. T wo of six reporting blurry vision and two of six reporting dizziness reported experiencing that symptom on the day the questionnaire was administered.



## Blood

A total of 24 (29% of the 84 total employees) participants agreed to have their blood drawn.

W ithin this group, venipuncture was unsuccessful

on three pa

rticipants, and 9 of the samples
collected clotted before arriving at the lab, making these specimens unsuitable for analysis. Consequently

, only 3 (23%) of 13 exposed, and 9 (13%) of 71 comparison blood samples were
available for analysis. All of the results for WBC, CBC, and PC were within the normal value range provided by the testing laboratory

. 3 0 No statistically si gnificant differences were detected
be tween the means of the blood indices for the exposed and comparison groups.



## Urine

A total of 23 (27% of 84) participant s provided
start-of-week and end-of-week urine specimens.

W ithin this group 4 partic ipants were unable to provide a start-of-week specimen and 2 participants were unable to prov ide an end-ofweek specime n. One specimen was excluded
from analysis because it had a creatinine
concentration that fell outside the acce ptable

range for this analysis (indicating that it cannot be
relied upon to accurately reflect the true body
burden of bromine). Consequently , there were 6 (46%) of 13 exposed and 10 ( 14%) of 71 comparison paired

urine specimens available for analysis. Resul ts of the urine bromine statistical analyses
are in T a ble 13. The start-of-week and end-ofweek u rine bromine concentrations for the exposed group were both statistically significantly higher than the corresponding values for the comparison group (p < 0.01). W e found no significant elevation in urine bromine l evel in the
end-of-week urine samples compared to the startof-week urine samples—in oth er words, we did

not detect an increase in urine bromine from the
firs t urine sample (start-of-week) to the second
urine sample (end-of-w eek). Regression analysis
of both start-of-week and end-of-week ur inary
bromine co ncentrations versus personal breathing

zone air conce

n trations of 1-BP demonstrated a statistically significant positive correlation.



## Neurobehavioral T

esting

A total of 30 part icipants participated in the
neurobehav ioral testing portion of the study;
included in this number were 12 (92%) of 13

e xposed, and 18 (25%) of 71 compar ison employees.

Postural Stability T

esting

Not all study subjects were able to complete the
entire Postural Stability test battery

. Six subjects ( one from the exposed group) were unable to
stand on either their right or left leg for a long enough period of time to complete both of the last two tests. Three subjects (all in the comparison group) were unable to stand for a long enough period of time on either their right or left leg to complete one of the last two tests. W e found no
d ifferences in the Postural Stability test resul t s between employees in the exposed and comparison groups.

Psychomotor Ability T esting

Results for each of the Psychomo tor Ability tests
can be found in T able 14. Every employee taking
part in the neurobe havioral testing completed theHealth Hazard Evaluation Report No.2000-0410-2891 Page 13

entire Psychomotor Ability test battery

. Of the 16
parameters tested, 3 demonstra ted a statistically significant di

fference between the exposed and comparison groups. In each case the mean test
value was higher (demonstrating increased effect)

in the exposed group. These three parameters
included right tremor pen intensity , right tremor pen frequency

, and slow rhythmic frequency finger tap standard deviation.

Regression analysis of each of these variables ( r ight tremor pen frequency

, right tremor pen intensity

, and standard deviation of slow rhythmic frequency finger tap) against PBZ air
concentrations o f 1-BP demonstrated a statistically significant positive correlation only for

r ight tremor pen frequency . No statistically significant co rrelation was demonstrated for right

tremor pen frequency when co mpared against
urine bromine concentr ations, and neither of the
other two variables mentioned above (right tremor

pen intensity or slow rhythmic frequency finger
tap standard deviation) demonstrated a statistically significant correlation with any of the measures of

exposure.



## Reproductive Evaluation

T en women agreed to participate in the reproductive portion of the evaluation. Four of the

wo men did not finish the study or provide urine samples or diaries. Only one of the women who completed the study was in the exposed group (working in the Fabricat i on area); all the others

were in the comparison (less expos ed) group. Additionally

, upon analysis of the urine specimens,
it became apparent that the one ex posed worker
did no t follow the correct procedure for urine
collection. Therefore, none of the data we collected for this portion of the survey was able to
be compared between exposed and comparison workers, and we will not be able to make any
determinations of potential fe male reproductive
effects of 1-BP exposu re in this HHE. The results of these menstrual cycle function an a lyses have been provided to the participants.



# D ISCUSSION

Exposure Survey

The 1-BP exposure data from the November 2000 sampling indicated that a ll 12 Sprayers had fullshift 1-B

P exposures above the Albemarle

exposure guideline of 25 pp m. Considering these findings, and the results of our ventilation

assessment, the NIOSH investigators concluded that the LEV system was not adequately removing

or controlling the 1-BP vapors. Additionally , the

area air sampling data indicated that low
concentrations of 1-BP and 2-BP were migrating

to nearby are as. Follow-up air sampling in July/August 2001, revealed decreased mean 1-BP

exposure of Sprayers by over 60% (22.5 ppm vs. 62.1 pp m). 2-BP exposures also decreased over
60% (0.2 ppm vs. 0.62 ppm). However

, measurements at two spray booths (Station #6 and

# 1 1) revealed concentrations of 1-BP t hat
remained above the Albemarle exposure g uideline.

Our obser vation of work practices at those
statio ns indicates that individual work habits of Sprayers (e.g., the amount of adhesive sprayed on
each cushion) are lik ely important factors contributing to the higher exposu res observed at those two spray booths.

Of note, some work practices which might have
been expect

ed to affect measured PBZ exposures

appe ared not to have a measurable impact in our

survey

. For example, some Sprayers stayed at
their workstations during their morning, lunch,
and/or afternoon breaks, while others left the
Fabricati on room and went outdoors or to other

areas of the building. Additionally

, Station #3, #6, #8, and #12 were set up to use a water-based

spray adhesive (not containing 1-BP), which if
used ex tensively during the day could result in
decreased BP exposures for workers. However

,Page 14 Health Hazard Evaluation Report No.2000-0410-2891

the water-based spray adhesive w as used only sporadically during this survey , and had no obvious
effect on BP exposures received by the Sprayers using it.

Some Sprayers used natural latex rubber gloves to prevent adhesive from getting on their skin. While
this may be effective in keeping adhesive off their skin, it does not protect against dermal exposure to

1-BP and 2-BP

. At least one manufacturer of BP products recommends using gl oves made of flexible laminates, such as V iton®. 31



## V entilation Assessment

Whenever there is a potential for a hazardous

exposure in a workplace, traditio nal industrial hygiene practice dictates that the fo l lowing hierarchy of controls, in decreasing order o f desirability and effectiveness, be implemented to protect worker health:

1. Elimination of the toxic s ubstance from the workplace.
2. Substitution of the toxic substance with a less toxic substance.
3. Installation of engineering controls designed to reduce exposure.
4. Use of administrative controls to reduce

exposure. 5. Use of personal protective equipment to reduce exposure.

In many instances, it is not possible to eliminate or substitute a chemical or material from a production process without altering the integrity of the desired product. Thus, many strategies for reducing

h azardous exposures center on the use of engineering controls such as process isolation
and/or local exhaust ven t ilation. At STN, 1-BP

vapors have largely been controlled using the spray booths at each workstation, with each booth discharging the captured air and vapors outside of the building. While spray booth operation as of the August 2001 site visit was an improvement over conditions observed during the NIOSH s urvey of November 2000, two things can be done to further improve LEV effectiveness. W ith the Poly room

garage door and Fabrication room outdoor exit
door closed, the plastic curtain separating the

Assem bly room from the Saw room began flapping due to the dramatic increase in airflow through this doorway into the Fabrication room.
This did not occur with the doors open. Keeping
th e doors closed is therefore more likely to
minimize the migration of solvent vapo rs into the

Saw room and rest of the building. Also, there appeared to be a large amount of unused space in
several of the spray booths. Minimizing the
unused volume within each spray booth, while not decreasing the work space so muc h that cushion assembly is hind ered, will result in an increase in
face velocity , without changing the exhaust fan speed, duct size, etc.



## Medical Survey

Questionnaire

Blurry vision and dizzi

ness were reported more commonly among the workers exposed to 1-BP compared to those who wer e less exposed.
Additiona l ly

, five of the six workers reporting blurry vision, and four of the six reporting dizziness, reported t hat the symptoms resolved
after leaving the work environment. Previous
studies hav e demonstrated vision changes related

to solvent exposure, 32

, 33 and o ther studies have
found that chronic mixed s olvent exposure can

cause an increase in the subjective symptom of
dizziness. 34

, 35 One of the two published case
reports concerning occupational 1-B P exposure
did mention that indivi

duals reported experiencing
dizziness during exposure, but neither of the published reports noted exposed persons reporting blurry vision. 20,21 The blurry vision and dizziness reported in our questionnaire, however

, are nonspecific symptoms which could have many poten tial causes, and the low participation rate inHealth Hazard Evaluation Report No.2000-0410-2891 Page 15

the study ma kes it difficult to determine whether
these findings are generalizable to th e overall study population.



## Hematological Effects

Our evaluation detected no association between occupational exposure to 1-BP an d changes in hematological indices; however

, beca use of the
small number of

blood specimens available for

an alysis, we cannot make a definite determination regarding the blood test results a n d their relationship to 1-BP exposure.



## Urinary Bromine

Our survey demonstrated that airborne 1-BP
concentrations were correlated with both start-ofweek and end-of-week urine bromine
concentrations. This finding is consistent with the findings of a previous 1-BP biological mo nitoring study

. 36 However , we did not demonstrate an
increase in urine bromine concentrations in the
end-of-week sample compared to the start-ofweek sample for indivi

duals or the group as a
whole. Possible explanations for this finding are: 1) bodily elimin ation of bromine via the kidneys

may be slow

, so that exposure to airborne 1-BP

over a 3-day period (the time over w hich we
collec ted our samples) does not affect urinary
bromine concentration at a level we can detect; and 2) exposure to 1-BP in the time period prior to our survey may have been greater than that during

our survey , leading to declining urine bromine levels (reflecting the decreased exposure). 

## Neurobehavioral

Psychomotor Ability T esting

In our survey the neurobehavioral test parameters
for freq uency and intensity of tremor in the right
hand were increase

d in the exposed group; right
hand tremor frequency alone was corr elated with
airborne 1-BP concentrations. Many different
types of occupat ional exposures, including exposure to solvents, have been associated with

tremor

. 37 In general, tremors related to toxic exposures are thought to be due to effects of the
toxins on the central nervous syst em and not the peripheral nervous system. 38

, 39 If 1-BP were to
have the same type of central mechanism, it is not likely that overexposure to 1-BP would cause a
unilateral tremor (tremor of one hand/arm and not
the other), which was the type of tremor our testing detected. Our findings of increased
unilateral tremor among t he exposed workers could be related to muscle fatigue of the right hand
and arm. Holding an adhesive spray gun (weighing 1 to 1.5 pounds) in on e hand

c onsistently while performing job activities could fatigue the muscles of that hand, arm and
sh oulder . Because the exposed group was tested late in the work day (after performing job activities
for 4–6 hours), it is likely that some level of hand

or arm fatigue was present in thes e individuals. Muscle fatigue can cause a mild tremor , which the

tremor pen test is sensiti ve enough to detect, and
the pen tremor test is unable to distinguish
between musc le fatigue tremor and neurological
based trem or of the hand and arm. W e did not
collect in formation concerning participants’
dominant hand, or wh ich hand they preferred to

use when holding the adhesive spray gu n, so we are unable to directly address that issue.

The time frame over which our tests were
admi nistered makes it impossible for us to distinguish whether the trem or detected might be
due to an acute or chronic condition or effect. ItPage 16 Health Hazard Evaluation Report No.2000-0410-2891

is possible that, in som e cases, the tremor we
noted is a result of a chronic neurological condition
unrelated to current work activities or exposure s (and which may have existed prior to work at STN). Therefore, for all the reasons listed above,

we are not able to determine the cause(s) of the tremor we observed with our medical testing.

A third p arameter , the standard deviation of slow rhythmic frequency finger tap, was also increased in the exposed group versus the comparison group.

However

, because

the corresponding test
parameter

, slow rhy thmic frequency finger tap

mean, was not increased in the exposed group, it
is likely that the finding related to the standard deviation is not meaningful.

Postural Stability T

esting

The postural sway studies we conducted failed to
demonstrate any significant d ifference in balance
b etween test groups despite the fact that the

s ymptom of dizziness was reported more frequently among the e xposed group. One possible r eason for this could be that the
“dizziness” reported in the questionnaire actually represented symptoms consistent with “lighthe adedness,” rather than vertigo or altered
balance. Additionally , the questionnaire addressed
symptoms occurring within the 30 days prior to our evaluation. If the symptom was transient (not

o c curring on the day of testing) the reported
symptoms would not necessarily correlate with objective testing.



## Survey Limit

ations

The ability of this survey to d etect any potential
associations between 1-BP exposure and healt h
effects was limited by several factors in addition

to those limitations listed above. The first
limitation was the small number of partic ipants,
dec reasing our ability to detect differences
between the exposed a nd comparison groups if they in fact existed. A second limitation was the low participation rate, which could lead to a selection bias (persons who participated may not
be representativ e of all the workers). A third
limitation involves the fact that the 1-BP exposures at STN were moderate in comparison

to other facilities in the U.S., particularly after
ventilation improvements wer e made at the plant.


# C ONCLUSIONS

Although we found th e Sprayers at STN to have
greater exposure to 1-BP than other em ployees doing di fferent work, we are unable to determine

if these exp osures constitute a health hazard.
Further investigation of potential health effects
related to oc cupational exposure to 1-BP is
needed before any definitive conclusions can be
made. Nevertheless, because of symptoms reported in our surv ey which are consistent with known effects of solvents, and because of

concerns raised in other studies, until more definitive informati

on is available we believe that

every reasonable effort should b e taken to
minimize 1-BP exposures. By enclosing the spray
booths in the Fab rication area, STN has dramatically reduced Sprayers’ exposures to 1-BP
and 2-BP

, as evidenced by reductions in full-shift, short-term, and ceiling exposures measured before
and after LEV improvements were made. Improvements in the ventilation of spray booths #6
and #1 1 are needed to bring those workstations up

to the level of th e remainder of the stations. W e also foun d that the latex gloves used by Sprayers do not protect them from dermal exposure to 1- or

2-BP

. Regarding our survey of urinary bromine concentrations, we f ound that urinary bromine
concentrations were

highly correlated to the
airborne concentr ation of 1-BP to which
individuals were occup ationally exposed at this facility . W

e conclude that urinary bromine may be

a good indicator of 1-BP exposure , however

, further research is needed to confirm our findings.Health Hazard Evaluation Report No.2000-0410-2891 Page 17 1. CDC [1989]. Guidelines for prevention of
transmis sion of human immunodeficiency virus
and hepatitis B virus to hea lth-care and public safety workers. MMWR 37 (suppl. S-6):1–37.

2. Szava K [2001]. Personal communication. Email of July 16, 2001, from S. Szava, Director of Education, American Conference of
Governmental Industrial Hygienists Worldwide (ACGIH

® ), to J. Nemhauser, Medical O fficer,
Medical S ection, Hazard Evaluations and

T echnical Assistance Branch, National Institute
for Occupational Safety and Health, Centers for
Disease Control and Prevent ion, Public Health Service, U.S. Depart ment of Health and Human
Services.

3. Dick RB, Setzer JV, Taylor BJ, Shukla R [1989]. Neurobehavioral effects of short duration

exposures to acetone and methyl ethyl ketone. Br
J Ind Med 46 :111–121.

4. Dick RB, Setze r JV, Wait R, Hayden MB, Taylor BJ, Tolos B, Putz-Anderson V [1984].
Effects of acute exposure of toluene and m ethyl ethyl ketone o n psychomotor performance.
International Archiv es of Occupational
Environmental Health 54 :91–109.

5. Dick RB, Kreig E

F Jr., Setzer J, Taylor B [1992] . Neurobehavioral effects from acute

expo s ures to methyl isobutyl ketone and methyl ethyl ketone. Fundamental and Applied Toxicology

19 :453–473.

6. Mikkelsen

S, Jorgensen M, Browne E, Gyldensted C [1989]. Mixed solvent exposure and organic brain damage. A study on pain t ers. Acta Neurologica Scandinavica Supplement 118 : 1–143. 

# R ECOMMENDA

TIONS

The following recommendations are made to assist

in minimizing worker exposure to 1-BP (and 2- BP).

1) STN should continue investigating the use of non-hydrocarbon solvent adhesives. This may require experimentation with the flow of cushion
parts with in Fabrication, since the water-based
adhesives do not ‘set up’ as quickly as does the current adhesive most frequently used at STN.

2) When buying a 1-BP based adhesive, STN
should choose the one with the lowest amount of
residual 2-BP

.

3) STN should provide Fabrication Sprayers with gloves th at protect against dermal exposure to 1-

BP and 2-BP; materials to consider include gloves
and aprons made from flexible la minates (e.g.,

V itonTM, 4HTM (PE/EV

AL), Silver ShieldTM).

4) The Fabrication room outdoor exit and the Poly

room garage doors should remain closed so that

vapor migra

tion into other areas of the building is
minimized.

5) The unused volume in each spray booth should
be decreased as much as po ssible to optimize the

current ventil a tion. This should increase the LEV
capture velocity and further lower worker

exposures.

6) Sprayers, and other employees using chemicals,
should not eat or drink at their workstations.

7) The findings of our medical survey do not by
themselves indicate that medical follow-up is
needed for any specific employees or groups of employees. However , employees who are experiencing health effects potentially related to
the workplace should be evaluated by a healthcare provider who has experience with occupational or environmental health issues.



# R EFERENCESPage 18 Health Hazard Evaluation Report No.2000-0410-2891

7. D ick RB, Bhattacharya A, Shukla R [1990].

Use of a compu terized postural sway

measurement sy stem for neurobehavioral
toxicolo gy. Neurotoxicology and Teratology

12 :1–6.

8. NIOSH [1995]. Research
Protocol-DBBS-95-02: Neurobeh avioral health
risks in far m workers. Cincinnati, OH: U.S. Depart ment of Health and Human Services,
Public Health Service, Centers for Disease
Control and Prevention, National I nstitute for Occupational Safety and Health.

9. B hattacharya A, Morgan R, Shukla R

, Rarnakrishanan H K, Wang L [1987].
Noninvasive estimation of afferent inputs for postural stability under low levels of alcohol. Annals Biomed Eng 15 :533–550.

10. Bhatt a charya A, Shukla R, Dietrich K,
Bornschein R, Berger O [1995]. Effect of early
lead exposu

r e on children's postural balance. Developmental Med Child Neurol 37 :861–878.

11. Danish Product Developme nt Ltd. [1994].

TREMOR 3.0 Users Man ual. Snekkersten,
Denmark.

12. NIOSH [1999]. Haza rd evaluation and
technical assistance report: Mercury Waste Solutions, Inc., Union Grove, WI. Cincinnati, OH:

U.S. De partment of Health and Human Services,
Public Health Service, Centers for Disease
Control and Prevention, Na tional Institute for Occupational Safety and Heal th, NIOSH HETA Report No. 1998-0320-2751.

13. NIOSH [1992]. Recommendations for occupational safety and health: compendiu m of policy documents and statements. Cincinnati, OH:

U.S. Department of Health and Hu man Services,
Public Health Service, Cen ters for Disease

Co ntrol and Prevention, National Institute for Occupational Safet y and Health, DHHS (NIOSH)
Publication No. 92-100. 14. AC GIH [2002]. 2002 TLVs® and BEIs®:
threshold limit values for chemical substances and physical agents. Cincinnati, OH: American
Conf erence of Governmental Industrial Hygienists.

15. CFR [2002]. 29 CFR 1910.1000. Code of
Federal Regulations. Washington, DC: U.S.

Government Printing Office, Office of the Federal Register.

16. Stump D [2001]. An inh a lation twogenera tion reproductive toxicity study of 1- bromopropane in rats. Study No. WIL-380001. Ashland, O H : WIL Research Laboratories. Unpublished. (Study sponsored by B r ominated Solvents Consortium [BSCO]).

17. Smith RL [2000]. Presentation titled “NPropyl Bromide” wh i ch was given on November
6, 2000, at a meeting between the U.S.
Environmental Pro tection Agency and the
Brominated Solvents Consortium.

18. Korean Ministry of Labour [2002]: Regulation

on t hreshold limit values for chemical substances
and physical

agents. Announcement No. 2002-8. Korean Ministry of Labour, Seoul, Korea.

19. Park JS, Kim Y, Park DW, et al. [1997]. An
outbreak of hematopoie tic and reproductive disorders due to solvents containing 2- bromopropane in an electronic factory, South

Korea: epidemiological

survey. J Occup Health
39:138–143.

20. Kim Y, Jung K, Hwan T, et al. [ 1996]. Hematopoietic and rep roductive hazards of South

Korean electronics workers exposed to solvents containing 2-bromopropane. Scand J Work
Environ Health 22:387–391.

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

An occupational health inves tigation of a factory producing 2-bromopropane in Ch ina. J Occup Health 39 suppl: S327.Health Hazard Evaluation Report No.2000-0410-2891 Page 19

22. Ichihara G, Aseda N, Kumazawa T, et al. [1997]. Testicular and hematopoietic toxicity of 2-bromopropane, a subs titute for ozone layer depleting chlorofluorocarbons. J Occup Health
39:57–63.

23. Kamijima M, Ichihara G, Yu X, et al. [1997]. Disruption of ovarian cyclicity due to 2-bromopropa ne in the rat. J Occup Health
39:3–4.

24. Yu IJ, Chu ng YH, Lim CH, et al. [1997]. Reproductive toxicity of 2-bromopropane in Sprague Dawley R ats. Scand J Work Environ
Health 23:281–288.

25. 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.

26. ACGIH [1998]. Industrial Ventilation. 23 r d ed., A Manual of Recomme n ded Practice.
Cinc innati, OH: American Conference of
Governmental Indust rial Hygienists. Fig 3-1, p.

3-3.

27. ACGIH [1998]. Industrial Ventilation. 23 r d ed., A Manual of Recommended Practice. Cincinnati, OH: American Conference of

G overnmental Industrial Hygienists. Table 3-1, p.

3-6.

28. ACGIH [1998]. Industrial Ventilation. 23 r d ed., A M a nual of Recommended Practice. Cincinnati, OH: American C onference of Governmental Industrial Hygienists. Fig 3-11, p. 3-

12.

29. ACGIH [1998]. Industrial Ventilation. 23 r d

e d., A Manual of Recommended Practice. Cincinnati, OH: Am erican Conference of

Governme ntal Industrial Hygienists. Fig 3-8, p.
3-9. 30. Normal range values for hematologic indices,

M edtox Laboratories, Inc., St. Paul, MN, Au gust 7, 2001.

31. Ensolv MSDS. World Wide Web [URL=www.ensolv.com. ], August 27, 2001.

32. Yasugi T, Kawai T, Mizunuma K, Kishi R, Harabuchi I, Yuasa J, Eguchi T, Sugimoto R, Seiji K, Ikeda M [1994]. Exposure monitoring and
health effect

studies of workers occupationally

expos ed to cyclohexane vapor. International
Archives of Occupational & Environmental Health
65 (5):343–350.

33. Kishi R, Eguchi T, Yasugi T, Katakura Y,

Arata Y, Harabuchi I, Ka wai T, Masuchi A [2001]. Effects of low-level occupational exposure

to styrene on color vision: dose relation wi th a urinary metabolite. Environmental Research

85 (1):25–30.

34. Horstman SW, Browning SR, Szel uga R, Burzycki J, Stebbins A [2001]. Solvent exposures in screen printing shops. Journal of Environmental
Science & Health Part A—Toxic/Hazardous
Substances & E

nvironmental Engineering
36 (10):1957–1973.

35. Juntunen J [19 93]. Neurotoxic syndromes
and occu pational exposure to solvents.
Environmental Research 60 (1):98–111.

36. Kawai T, Takeuchi A, M iyama Y, Sakamto K, Zhang ZW, Higashikawa K, Ikeda M [2001]. Biological monitoring of occupati onal exposure to 1-bromopropane by means of urinaly sis for 1- bromopropane and bromide ion. Biomar kers
6 (5):303–312.

37. Dick F, Semple S, Chen R, Seaton A [2000]. Neurological deficits in solvent-exposed painters:

a syndro me including impaired colour vision, cognit ive deficits, tremor and loss of vibration sense. QJM 93 (10):655–661.Page 20 Health Hazard Evaluation Report No.2000-0410-2891

38. Troster AI, Woods SP, Fields JA, Lyons KE,
Pahwa R, Higginson CI, Koller WC [2002]. Neuropsychological deficits in essential tremor: an expression of cerebello-thalamo-cortical pathophysiology? Eur J Neurol 9(2) :143–51.

39. Deus chl G, Bergman H [2002]. Pathophysiology of nonparkinsonian tremors. Mov
Disord 17 (Suppl 3):S41–48.Health Hazard Evaluation Report No.2000-0410-2891 Page 21 

### T able 1 Full-Shift PBZ air sampling results for 1- and 2-BP

STN Cushion Company Thomasville, North Carolina

HET A 2000-0410-2891 November 14, 2000

T ables

Job Title Department Sample
Time (min.) Sample

V olume (L) Concentration, ppm, 8-hr

. TW A

1-BP 2-BP

Sprayer Fabrication 498 25.0 41.3* 0.5*

Sprayer Fabrication 496 25.0 143.0* 1.4*

Sprayer Fabrication 495 25.0 74.7* 0.8*

Sprayer Fabrication 296 15.0 29.4 0.2

Sprayer Fabrication 494 24.9 73.4* 0.7*

Sprayer Fabrication 487 24.5 48.6* 0.5*

Sprayer Fabrication 492 24.9 75.8* 0.8*

Sprayer Fabrication 494 24.9 78.3* 0.7*

Sprayer Fabrication 491 24.8 51.3* 0.6*

Part T ime Fabrication 350 17.5 34.7 0.4

Part T ime Fabrication 282 14.1 32.3 0.3

Part T ime Fabrication 350 17.5 41.3 0.5

Floater Fabrication 345 17.3 6.3 0.1

Floater Fabrication 349 17.5 14.1 0.2

Recommended exposure guideline 25 1

Minimum Detectable Concentration (MDC) 0.01 0.01

Minimum Quantifiable Concentration (MQC) 0.03 0.02

* For sampling periods longer than 8 hrs., the average concentrations for the time sampled is given.Page 22 Health Hazard Evaluation Report No.2000-0410-2891 

### T able 2
Short T erm (15-minute) PBZ air sampling results for 1- and 2-BP

STN Cushion Company Thomasville, North Carolina

HET A 2000-0410-2891 November 14, 2000

Job Title Department Sample
Time (min) Sample

V olume (L) Concentration, ppm

1-BP 2-BP

Sprayer Fabrication 17 3.4 173.9 1.56

Sprayer Fabrication 17 3.4 1 10.1 1.04

Sprayer Fabrication 16 3.2 55.4 0.54

Sprayer Fabrication 16 3.2 92.3 0.98

Sprayer Fabrication 15 3.0 72.2 0.62

Sprayer Fabrication 15 3.0 33.7 0.38

Sprayer Fabrication 15 3.0 42.6 0.3

Sprayer Fabrication 15 3.0 65.6 0.54

Sprayer Fabrication 15 3.0 138.5 1.05

Minimum Detectable Concentration (MDC) 0.06 0.06

Minimum Quantifiable Concentration (MQC) 0.23 0.18Health Hazard Evaluation Report No.2000-0410-2891 Page 23 

### T able 3 Ceiling (5-minute) PBZ air sampling results for 1- and 2-BP

STN Cushion Company Thomasville, North Carolina

HET A 2000-0410-2891 November 14, 2000

Job Title Department Sample
Time (min) Sample

V olume (L) Concentration, ppm

1-BP 2-BP

Sprayer Fabrication 5 1.2 151.9 1.13

Sprayer Fabrication 6 1.6 51.9 0.49

Sprayer Fabrication 6 1.5 44.3 0.59

Sprayer Fabrication 5 1.2 1 14.3 1.13

Sprayer Fabrication 5 1.3 70 0.81

Sprayer Fabrication 6 1.5 102.8 1.08

Sprayer Fabrication 6 1.6 48.7 0.63

Sprayer Fabrication 6 1.6 39.5 0.37

Sprayer Fabrication 6 1.6 72.2 0.8

Sprayer Fabrication 5 1.2 49.7 0.56

Sprayer Fabrication 5 1.5 67.6 0.69

Minimum Detectable Concentration (MDC) 0.12 0.12

Minimum Quantifiable Concentration (MQC) 0.5 0.37Page 24 Health Hazard Evaluation Report No.2000-0410-2891 

### T able 4 Full-Shift Area Air Sampling Data for 1- and 2-Bromopropane

STN Cushion Company Thomasville, North Carolina

HET A 2000-0410-2891 November 14, 2000

Sample Location Sample
Time (min) Sample

V olume (L) Concentration, ppm

1-BP 2-BP

In the middle of the Saw room 480 46.3 7.7 0.2

In the middle of the Fabrication room 478 47.0 7.2 0.1 1

In the middle of the Poly room 474 45.9 1.7 0.05

Minimum Detectable Concentration 0.004 0.004

Minimum Quantifiable Concentration 0.02 0.01Health Hazard Evaluation Report No.2000-0410-2891 Page 25 T able 5 – Full shift PBZ air sampling results for 1- and 2-BP

HET A 2000-0410-2891 STN Cushion Company , Thomasville, North Carolina

July 31 to August 2, 2001

Sample

location Concentration (ppm), 8-hr TW A

A verage 1-BP

exposure July 31 August 1 August 2

sample vol (L) 1-BP 2-BP sample vol (L) 1-BP 2-BP sample vol (L) 1-BP 2-BP

Station #1 43.6 8.8 0.1

Station #2 43.8 15 0.2 45.8 10.6 0.1 48.3 20.7 0.1 15.4

Station #3 43.4 15.1 0.1 48.6 14.2 0.1 47.4 24.8 0.2 18

Station #4 42.7 21.1 0.2 49.2 16.3 0.2 37.3 19.9 0.2 19.1

Station #5 34.6 14.7 1,

2 0.2 44 16.11 0.2 46.7 23.8 1,2,3 0.2 18.2

Station #6 35.9 31.9 0.3 30.1 17 W ,1 0.1 45.9 34.9 0.4 27.9

Station #7 35 16.5 1,

2 0.1 44.9 17.3 0.2 47.3 15.3 1,2,3 0.2 16.4

Station #8 31.1 13.91 0.1 32.5 17.5 0.1 45.3 14.3 0.2 15.2

Station #9 34.3 15.11 0.2 27.8 7.7 0.1 49.3 28.43 0.3 17

Station

#10 34 11.8 0.1 42 21.81 0.2 23.7 17.8 2,3 0.2 17

Station

#11 33.8 15.81 0.2 44.4 29 0.2 47.4 32.71 0.3 25.8

Station

#12 34 18.9 W 0.2 45.3 17.81 0.2 46.5 24.1 1,3 0.2 20.2

Mean 16.6 0.2 16.8 0.1 23.3 0.1Page 26 Health Hazard Evaluation Report No.2000-0410-2891

Recommended exposure guideline 25 ppm

Minimum Detectable Concentration 0.003 1 ppm

0.003

0.009

1 Stayed in Fabrication during morning break. 2 Stayed in Fabrication during lunch break.

3 Stayed in Fabrication during afternoon break. W Station that periodically used water-based spray adhesive.Health Hazard Evaluation Report No.2000-0410-2891 Page 27 

### T able 6 Short term (15 minute) PBZ air sampling results for 1- and 2-BP

HET A 2000-0410-2891 STN Cushion Company Thomasville, North Carolina July 31 to August 2, 2001

Sample location Sample volume (L) 1-BP , ppm 2-BP

, ppm

Station #2 3 8 Trace*

Station #3 3 16 0.2

Station #5 3.2 26 0.3

Station #6 3 47 0.4

Station #7 3 31 0.3

Station #8 3 7 Trace

Station #9 3 56 0.2

Station #10 3 40 0.4

Station #1 1 3 0.2 Trace

Station #12 3 25 0.2



### Minimum Detectable Concentration 0.05 0.04 Minimum Quantifiable Concentration 0.13 0.13

* T race concentrations fall between the MDC and the MQC.Page 28 Health Hazard Evaluation Report No.2000-0410-2891 

### T able 7 Ceiling (5 minute) PBZ air sampling results for 1- and 2-BP

HET A 2000-0410-2891 STN Cushion Company Thomasville, North Carolina July 31 to August 2, 2001

Sample location Sample vol. (L) 1-BP , ppm 2-BP

, ppm

Station #2 1 32 ND*

Station #3 1.1 21 ND

Station #4 1 35 0.5

Station #5 1 26 ND

Station #6 1 ND ND

Station #7 1 ND ND

Station #8 1 ND ND

Station #9 & 12** 1.1 ND ND

Station #10 1.3 29 ND

Station #1 1 1 38 ND



### Minimum Detectable Concentration 0.14 0.12 Minimum Quantifiable Concentration 0.4 0.4

* ND— ‘Not Detected’, concentrations are below the MDC.

**W orker worked at both booths during this time.Health Hazard Evaluation Report No.2000-0410-2891 Page 29 

### T able 8 Air sampling results from non-sprayers

HET A 2000-0410-2891 STN Cushion Company Thomasville, North Carolina July 31 to August 2, 2001

Sample type Date Location Sample vol (L) 1-BP

, ppm, 8-hr TW A 2-BP

, ppm, 8-hr . TW A

PBZ 1 37102 Shipping 36.1 5.8 0.1

PBZ 37102 Tick cutting 36 5.4 0.1

PBZ 37102 Sewing 36.1 5 0.1

PBZ 37102 Pattern room 35.9 4.6 0.1

PBZ 37102 Front office 36.5 4.2 0.1

GA 2 37102 Outside on fence 19.5 0.01 ND*

GA 37102 Outside near fab. AC unit 22.6 0.01 ND

PBZ 37103 Poly cut 45.6 2.4 0.04

PBZ 37103 Feather room 1 1.8 1.1 0.03

GA 37103 Pattern room 48 5 0.09

PBZ 37103 Fabric cut 19.8 2 0.04

GA 37104 Fabrication doorway into

Saw room 43.4 6.1 0.1

GA 37104 Poly cut 44.9 4.1 0.1

PBZ 37104 Sewing 47.2 5.2 0.1

PBZ 37104 Poly cut 47 3.8 0.1

GA 37104 Front office 44.9 3.1 0.1

GA 37104 I-beam in Poly cut 42.4 5 0.1



### Minimum Detectable Concentration 0.004
0.003 Minimum Quantifiable Concentration 0.01 1 0.01 1

1 PBZ— Personal Breathing Zone.

2 GA— General Area.Page 30 Health Hazard Evaluation Report No.2000-0410-2891

* ND— ‘Not Detected’, concentrations are below the MDC.Health Hazard Evaluation Report No.2000-0410-2891 Page 31 

### T able 9 Capture velocity and exhaust flow rate for Fabrication workstations (before enclosure).

HET A 2000-0410-2891 STN Cushion Company Thomasville, North Carolina April 18, 2001

W orkstation number Measured capture velocity at 3 ft 1

ft/min Calculated

Flow rate
CFM 2

1 6 231

2 N/V 3 283

3 24 755

4 73 1545

5 37 546

A* 14 454

6 N/V 646

7 44 917

8 31 612

9 6 615

10 24 447

1 1 8 527

12 30 593

B* 26 564

1 V alue for workstation 6 is measured at a distance of 18 inches above the surface of the downdraft table.

2 Cubic feet per minute.

3 N/V—No data was available for this condition. * These two booths removed before next evaluation, T able10.Page 32 Health Hazard Evaluation Report No.2000-0410-2891 

### T able10

A verage Spray Booth V

entilation Hood Face V

elocity (after enclosure)

HET A 2000-0410-2891 STN Cushion Company Thomasville, North Carolina July 31 to August 2, 2001

S tation # # measurements

used to average Capture V elocity* w/doors open (ft/min) Capture V elocity w/doors closed (ft/min)

1 & 2 28 57 70

3 20 30 50

4 20 34** 37

5 20 35 37

6 20 41 39

7 20 25 27**

8 20 17 24

9 & 10 28 26** 25

1 1 20 19 21

12 20 18 18

* Measured at 3 ft from the LEV hood. ** Indicates that measurements were only taken once, rather than twice as done for the other average values.Health Hazard Evaluation Report No.2000-0410-2891 Page 33Page 34 Health Hazard Evaluation Report No.2000-0410-2891 

### T able 1 1 Characteristics of Study Participants Completing Questionnaire

HET A 2000-0410-2891 STN Cushion Company Thomasville, North Carolina July 31 to August 2, 2001

Characteristic Participants in Exposed Group (N=12) Participants in Comparison Group (N=18)
# (%) Female 12 (100%) 15 (83%)

Mean Age in Y

ears (Range) 44 (29-65) 36 (21-55)

# (%) White 8 (67%) 16 (89%)

# (%) Black 4 (33%) 2 (1 1%)

Mean Length of Employment at
STN in Months (Range) 13 (2-24) 21 (1-85)

# (%) Reporting Prescription
Medication Use 6 (50%) 7 (39%)

# (%) Reporting Exposure to
Other Substances of Concern 1 

### 2 (17%) 7 (39%)

# (%) Smoking Cigarettes 2 

### 5 (42%) 10 (56%)

1 Question asked if individual had any hobbies, household chores, part-time jobs or other activities that involve use of arsenic, mercury

, lead, cadmium, solvents, pesticides or other chemicals.

2 Individuals who responded “yes” to the question “Do you currently smoke cigarettes?”Health Hazard Evaluation Report No.2000-0410-2891 Page 35 

### T able 12 Reported Symptoms and Odds Ratios Among 1-Bromopropane Exposed and Comparison Groups

HET A 2000-0410-2891 STN Cushion Company Thomasville, North Carolina July 31 to August 2, 2001

Symptom # (%) of

Participants Reporting Symptom - Exposed Group
N=12 # (%) of

Participants Reporting Symptom - Comparison Group
N=18 Odds

Ratio 95 % Confidence

Interval Lower - Upper

Anxiety , nervousness 2 (17%) 2 (11%) 1.78 0.21 14.86 Appetite increase 0 (0%) 2 (11%) § § § Appetite decrease 0 (0%) 0 (0%) § § §

Blurred vision 6 (50%) 1 (6%) 16.00* 1.58 162.10 Trouble concentrating 1 (8%) 0 (0%) § § § Depression 3 (25%) 1 (6%) 6.00 0.54 67.28

Diarrhea 1 (8%) 1 (6%) 1.60 0.09 28.57 Dizziness; feeling “off

balance” 6 (50%) 1 (6%) 15.00* 1.48 152.50

Felt drunk, “high,”

“stoned” 1 (8%) 0 (0%) 1.10 0.91 1.33

Headache 7 (58%) 7 (39%) 2.00 0.45 8.96 Memory loss; forgetfulness 2 (17%) 2 (11%) 1.50 0.18 12.46

Nausea 4 (33%) 2 (11%) 3.75 0.56 25.12 Numbness or “pins and needles” feeling in

hands 3 (25%) 3 (17%) 1.67 0.28 10.09

Numbness or “pins and needles” feeling in

feet 4 (33%) 1 (6%) 9.71 0.92 103.04

Sleeping too much 2 (17%) 1 (6%) 3.78 0.30 47.56 Trouble falling asleep or staying asleep 5 (42%) 3 (17%) 4.17 0.75 23.18

Tremor or shakiness 2 (17%) 1 (6%) 4.25 0.33 54.07

W eakness/clumsiness

in hands 1 (8%) 2 (11%) 0.80 0.06 10.01

Problems with hand writing 1 (8%) 1 (6%) 1.70 0.10 30.28

W eakness in arms 3 (25%) 3 (17%) 1.88 0.31 11.52

W eakness in feet 2 (17%) 0 (0%) 1.22 0.93 1.62

W eakness in legs 3 (25%) 1 (6%) 6.38 0.57 71.27

W alking problems 1 (8%) 0 (0%) 1.10 0.91 1.33

W eight loss 1 (8%) 1 (6%) 1.70 0.10 30.28

§ One or more of the contingency table counts was equal to zero

.Page 36 Health Hazard Evaluation Report No.2000-0410-2891 * Asterisks indicate a significant difference from the comparison group (*p<0.05.)Health Hazard Evaluation Report No.2000-0410-2891 Page 37 

### T able 13 Urine Bromine Analysis Of 1-Bromopropane Exposed and Comparison Groups

HET A 2000-0410-2891 STN Cushion Company Thomasville, North Carolina July 31 to August 2, 2001

Measure (Matched Pair) Population Number Subjects Geometric

Mean 1 

### Minimum

V alue 1 

### Maximum

V alue 1 

### Probability

(p value)
Start-of-week Urine
Bromine
Concentration Exposed 7 6.4 1.8 14.0 0.005*

Comparison 10 1.9 1 3.5

End-of-week Urine
Bromine
Concentration Exposed 7 7.7 2.5 38.0 0.003*

Comparison 12 2 0.8 6.2

Post Minus PreExposure
Concentration (Difference) Exposed 6 -0.42 -3 3.1 0.710 3



### Comparison 10 0.1 2 

### -1.3 3.6 0.917 3

1 Concentration is reported in milligrams per liter

. 2 V alue is arithmetic mean (Geometric mean can not evaluate negative numeric data.)

3 T est V alue = 0, H

o : mean of sample = 0 (For exposed group expect mean to be > 0, for comparison group expect mean to be = 0.)

* Asterisks indicate a significant difference from the comparison group (*p<0.05.)Page 38 Health Hazard Evaluation Report No.2000-0410-2891 

### T able 14
Neurobehavioral T

est Parameter Analysis Of 1-Bromopropane Exposed and Comparison Groups

HET A 2000-0410-2891 STN Cushion Company Thomasville, North Carolina July 31 to August 2, 2001

Measure Population Number Subjects Mean Minimum
V alue Maximum

V alue Probability

(p value)

T remor Pen Right – Intensity (meter/second 2 

### ) Exposed 12 0.14 0.10 0.22 0.033* Comparison 18 0.1 1 0.06 0.16

T remor Pen Right – Frequency (Hertz) Exposed 12 7.5 5.7 8.8 0.001* Comparison 18 6.3 4.5 8.8

T remor Pen Right –
Harmonic Index Exposed 12 0.92 0.85 0.99 0.717 Comparison 18 0.92 0.85 0.98

T remor Pen Left – Intensity (meter/second 2 

### ) Exposed 12 0.1 1 0.07 0.19 0.241 Comparison 18 0.10 0.06 0.16

T remor Pen Left – Frequency (Hertz) Exposed 12 6.5 4.4 9.2 0.882

Comparison 18 6.4 4.7 8.4

T remor Pen Left – Harmonic
Index Exposed 12 0.90 0.87 0.95 0.100

Comparison 18 0.88 0.79 0.98

Reaction T

ime – Mean Exposed 12 0.264 0.183 0.354 0.415

Comparison 18 0.248 0.189 0.310
Reaction T

ime –
Standard Deviation Exposed 12 0.048 0.020 0.090 0.917 Comparison 18 0.049 0.029 0.105

Slow RF 1 

### Finger T

ap – Mean Exposed 12 -0.056 3 

### -0.158 0.022 0.253

Comparison 18 -0.071 3 

### -0.164 0.027
Slow RF 1 

### Finger T

ap – Standard Deviation Exposed 12 0.059 0.018 0.1 14 0.015* Comparison 18 0.044 0.029 0.096Health Hazard Evaluation Report No.2000-0410-2891 Page 39 

### T able 14 (Continued)
Neurobehavioral T

est Parameter Analysis Of 1-Bromopropane Exposed and Comparison Groups

HET A 2000-0410-2891 STN Cushion Company Thomasville, North Carolina July 31 to August 2, 2001

Measure Population Number Subjects Mean Minimum
V alue Maximum

V alue Probability

Fast RF 1 Finger T

ap – Mean Exposed 12 -0.060 3 -0.154 -0.001 0.755

Comparison 18 -0.051 3 -0.139 0.014

Fast RF 1 Finger T

ap – Standard Deviation Exposed 12 0.047 0.008 0.1 15 0.062 Comparison 18 0.029 0.016 0.131 Maximum Frequency Finger

T ap Exposed 12 5.0 1.6 7.5 0.819

Comparison 18 5.2 3.2 7.5

Slow P/S 2 RF 1 – Mean Exposed 12 -0.065 3 -0.138 0.004 0.692 Comparison 18 -0.066 3 -0.149 0.077

Slow P/S 2 RF 1

– Standard Deviation Exposed 12 0.066 0.032 0.155 0.602 Comparison 18 0.056 0.032 0.136

Maximum Frequency P/S 2 Exposed 12 3.7 2.5 6.0 0.491 Comparison 18 3.2 1.0 4.9

1 Rhythmic Frequency

. 2 Pronation/Supination

. 3 V alue is arithmetic mean (Geometric mean can not evaluate negative numeric data.)

* Asterisks indicate a significant difference from the comparison group (*p<0.05.)Page 40 Health Hazard Evaluation Report No.2000-0410-2891



# A PPENDIX

Brominated Solvent

s 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 phaseout of several ozone-depleting substances under

T itle VI of the law

. 1 

### The law targeted the complete phase-out of several su bstances 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, ad hesive coatings applications, and
solvent applications. 2 

### The CAA amendment provisions were in part enacted to abide by the

terms of a United Nations (UN) internati onal

ag reement, The Montreal Protocol on
Substances that Deplete the Ozone Layer adopted in 1987, which committed to reduce and eventually eliminate the use of oz o ne-depleting
substances. As a result, several countries
discontinued and prohibited further use of ozonedepleting substances. 3 

### Under Section 612 of the CAA, ozone-deple ting substances were to be replaced with alternative substances or processes that reduced the risks to huma n health and the
environment. 1 

### T

o fulfill the law’s requirement, the
Environmental Protection Agency (EP A) initiated the Significant New Alternatives Policy (SNAP)

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



### The solve nts 1-bromopropane (1-BP) and 2- bromopropane (2-BP) were introduced into workplaces around the worl d as substitutes for ozone-depleting substances following initiation of the 1987 UN international treaty

. The physical properties of these two solvents, incl uding high

v olatility and low flammability , were seen as favo rable characteristics for a non-aerosol
solvent. Due to photochemical breakdown, the solvents have a relatively short atmospheric halflife (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 O ccupational Safety and Health
Administration (OSHA) analysis of several

commer cial 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 T e s ting 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 po t ential
alternative to ozone-depleting substances. 2 

### At
this time, the EP

A 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-Bromoprop

ane

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

rats when exposed to concentrations greater than

or equal to 20 0 parts per million (ppm) of
1-BP

. 11

, 12 

### T

w o studies noted mild hepaticHealth Hazard Evaluation Report No.2000-0410-2891 Page 41



### changes in rats exposed to greater than or equal

to 800 ppm of 1-BP; these changes were
considered adaptive and r eversible due to the
absence of

other signs of hepatotoxicity

. 11, 13

, 14



### A lthough 2-BP exposure has been associ ated
wi t h pancytopenia, animal studies evaluating potential hematopoietic effects of 1-BP exposure have yielded no firm conclusions. The median
lethal inhalation concentr ation 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
functionin g by electrophysiologic testing and morphologic or histopathologic abnormalities of
central and peripheral nerves. 15

, 16

, 17 

### T w o of
these three studies also demonstrated a prominent weakness of the hind limbs following

expos u re. 15,17 

### A fourth study demonstrated
decreased peri

pheral 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. 1 7 

### This same study and one
other came to the conclusion that 1-BP was a

more potent neurot

o xicant 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
firs t 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
han d... transient dysphagia and urinary
difficulties.” 19 

### The physical findings, magnetic

resonanc e 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 acqu i red neuropathy

, but
with evidence of central nervous system
involvement as well.”

The EMG did not indicate

any ev idence of muscle denervation. The
individual did demonstrate improvement fol l owing
removal from exposure, but was lost to follow-up
before it was determined i f the health effects would fully resolve.

The second case report concerned three females,

ages 35, 30, a nd 50, each working at cushion manufacturing companies in North C arolina. 2 0



### 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 intermitt

e ntly and workers wore latex gloves for dermal exposure protection. The
first worker’s symptoms develo ped one year following the replacement of a dichloromethanebased 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 reportPage 42 Health Hazard Evaluation Report No.2000-0410-2891



### did state that one worker was found to have time-weighted average (TW A) exposures of between 60 to 261 ppm of 1-BP over several days of monitoring 5 months after symptoms had
started.

“The t hree workers showed the common
symptoms of staggering, nu mbness and paresthesia/dysesthesia with a similar distribution in their feet, legs, thighs, lower back and hips as
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 worke r s included temporary menstrual cycle disruption for

two of the three women, diarrhea, abnormal sweating, and urinary incontin ence. The
researchers concluded that 1-B P 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 in

formation is available from an unpublished abstract submitted at the 2002
Annual Meeting of the Society of T oxico logy regarding the on

l y 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 neurologic a l effects, comparing them to a group of 27 unexposed
controls. Neurobehavioral and electrop hysiological assessments of nerve
function were performed on both g r oups. Because of the limited nature of the information

p resented in this abstract, it is difficult to draw conclusions from this study

. 

## Review of Literature—

2-Bromoprop

ane

Following 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 o f 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 elevat ed 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 dem

onstrated 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 

### T w o studies recently demonstrated peripheral neurotoxic change s 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 Spragu e -Dawley rat has been estimated to be 31,171 ppm. 30Health Hazard Evaluation Report No.2000-0410-2891 Page 43 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: P r otection of stratospheric ozone: Notice 14 for significant new alternatives policy program; notice of acceptability; request for information.

3. U nited Nations Environmental Program m e [2000]. Ozone Treaties. [http://www.unep.ch/ozone/treaties.s h tml]. Date accessed: May 5, 2002.

4. 58 Fed. Reg. 54892 [1993]. Environmental
Protection Agency: Protection of stratospher i c ozone; final rule.

5. Donaghy T, Shanahan I, Hande M, Fitzpatrick

S [1993]. Rate constants and atmospheric
lifetimes for the reactions of O H 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 re action

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

7. Aldrich Chemical Compa n y. 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,
Direct orate 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 gr ade normal-propyl bromide. West 

### One study has been conducted to ev aluate the
health effects of 2-BP on employees working at

a 2-BP manufacturing

plant. During the study

, conducted in 1996, worker brea thing zone

exposure concentrations ranged f rom 0.80 to
16.18 ppm as an 8-hour TW A

. The study included worker interviews, medical examinations, and specific testing of reproductive and hematological indices. “No severe cases of reproductive or hematopoietic disorder s were found at (exposures) less than 10 ppm (TW A),
but a possible adverse effect of 2-bromopropane on hematopoiesis could not be disproved.” 31



## 1-Bromoprop

ane Biomarker of Exposure

A study has demonstrated th at 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

, uri nary 1-BP detection requires gas chromatography-mass spectrometry (GCMS) instrumentation and the specimen must be immediately analyzed after collection. Most
clinical laboratorie s 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

. 

## Appendix ReferencesPage 44 Health Hazard Evaluation Report No.2000-0410-2891

Conshohocken, PA: American Society for Testing
Materials.

11. Ichihara G, Yu X, Kitoh J, Asaeda N,

Kumazawa T, Iwai H, Shibata E, Yamad a T, Wang H, Xie Z, Maeda K, Tsukamura H,
Takeuchi Y [2000]. Reproductive toxicity of 1-
b romopropane, a newly introduced alternative to

ozone layer depleting solvents, i n male rats. Toxicological Sciences 54 :416–423.

12. Stump D [2001]. An inhlation two-generation reproductive toxicity study of 1-b romopropane in rats. Study No. WIL-380001.

Ashland, OH: WIL Resea r ch Laboratories. Unpublished. (Study sponsored by Br o minated Solvents Consortium [BSCO]).

13. Kim HY, Chung YH, Jeong JH, Lee YM, Sur GS, Kang JK [1999]. Acute and repeated
inhalati on 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 a nd Human Services,
National Institutes of Health, National Inst itute 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, Take uchi Y [2001]. Neurotoxicity of 2-bromopropane and 1-bromopropane,
alterna t ive solvents for chlorofluorocarbons.
Environmental Research 85 (1):48–52.

16. Wang H, Ich ihara G, Ito H, Kato K, Kitoh J,
Yamada T, Yu X, Tsuboi S, Moriyama Y,
Sakat ani R, Shibata E, Kamijima M, Itohara S,

Ta keuchi Y [2002]. Biochemical changes in the
central nervous system of rats exposed to 1- bromopropane fo r 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 solve nts, is dose-dependently neuroto xic to rats in long-term
inhala tion exposure. Toxicological Sciences

55 :116–123.

18. Zhao W, Aoki K, Xie T, Misumi J [1999].

E lectrophysiological changes induced by different doses of 1-bromopropane and 2-bromopropane. J Occup Health 41 :1–7.

19. Sclar G [1999]. Encephalomyeloradiculoneuropathy following exposure to an

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

20. Ichihara G, Miller JK, Ziolkowsk a A, Itohara S, Takeuchi Y [200 2]. Neurological disorders in
three workers exposed to 1-b romopropane. J Occup Health 44 :1–7.

21. Ichihara G, Li W, Shibata E, Ding X, Kamiji ma M, Wang H, Liang Y, Peng S, Itohara S, F a n Q, Zhang Y, Zhong W, Wu X, Valentine WM, Takeuc hi Y [2002]. Neurological abnormality in workers of 1-bromopropane factory [Abstract]. Presented at the 41 s t Annual Meeting
of the S ociety 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 ex posed 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 d isorders due to solvents containing 2-bromopropane in an elec tronicHealth Hazard Evaluation Report No.2000-0410-2891 Page 45

factory, South Korea: epid emiological 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 nonpregnant female rat. J Occup Health 3 9 :144–149.

25. Kamijima M, Ichihara G, Yu X , Xie Z, Kitoh J, Tsukamura H, Maeda K, Nakajima T, A saeda 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 S H, Lee JY, Chung YH,

Kim TG, Park JH, Moo n YH, Yu IJ [1997]. Effects of 2-bromopropane on the female reproductive function in Spra g ue-Dawley rats.
Industrial Health 35 :278–284.

27. Yu IJ, Chung YH, Lim CH, Maeng SH, Lee JY, Kim HY, Lee SJ, Ki

m 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, Kamaji ma 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.

29. Yu X, Ichihara G, Xie Z, Shibata E, Kamijima M, Asaeda N, Hisanaga N, Takeuchi Y [1999].
Effect of inha lation 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]. LC 5 0 of 2-bromo propane. 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. Kawa

i 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 bromid e ion.
Biomarkers 6 (5):303–312.DEP

ARTMENT OF HEAL TH AND HUMAN SERVICES
Centers for Disease Control and Prevention National Institute for Occupational Safety and Health 4676 Columbia Parkway Cincinnati, OH 45226-1998

OFFICIAL BUSINESS Penalty for private use $300

Delivering on the Nation's promise: Safety and Health at work for all people through research and prevention



### T o receive NIOSH documents or information about occupational Safety and Health topics

contact NIOSH at:

1-800-35-NIOSH (356-4674) Fax: 1-513-533-8573 E-mail: pubstaft@cdc.gov
or visit the NIOSH web site at:

www .cdc.gov/niosh/homepage.html

S A F E R • H E A L T H I E R • P E O P L ETM