HETA 92-128-2241 NIOSH INVESTIGATORS:

JULY 1992 John Decker, M.S.

TINA AND ANGELA'S NAIL SALON Amy Beasley

SPRINGDALE, OHIO

I. Summary

In response to a request from the Springdale Health Department in Springdale, Ohio,

representatives from the National Institute for Occupational Safety and Health (NIOSH)

conducted an industrial hygiene evaluation of exposures to chemicals used during the application of

sculptured nails. The request stated that an adjacent business in the same building had complained

of a "terrible odor" emanating from the nail salon. No health effected were noted on the request.

Bulk samples of liquids and powders used to sculpture nails were collected and analyzed

qualitatively by gas chromatography/mass spectrometry. Based on these results, personal and area

air sampling was conducted in the nail salon for methyl and ethyl methacrylate, acetone, and

benzene. No methyl methacrylate or benzene vapors were detected. Low concentrations of ethyl

methacrylate (ranged from non-detected to 7 parts per million [ppm]) and acetone vapors (6 and

10 ppm) were detected. There are no occupational exposure criteria for ethyl methacrylate;

however, Patty's Industrial Hygiene and Toxicology suggests that industrial hygiene

recommendations for methyl methacrylate can be applied to ethyl methacrylate. All exposures

were below the NIOSH Recommended Exposure Limit (REL) time-weighted average (TWA)

criteria of 100 ppm for methyl methacrylate and 250 ppm for acetone.

An inspection of the heating and cooling system serving the salon indicated that there was

no provision for the mechanical introduction of outside air to the salon. The American

Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE)

recommends that 25 cubic feet per minute (cfm) of outside air be supplied to beauty

salons.

Several chemicals (methacrylates, acetone) used in nail salons emit vapors

having low odor thresholds. Under certain conditions these odors can be

detectable in adjacent businesses. However, concentrations of these

vapors, as measured on the day of the NIOSH survey, do not constitute a

health hazard to the workers and customers at Tina and Angela's Nail Salon

or to adjacent businesses. Recommendations to prevent the migration of

vapors from the salon to adjacent businesses can be found in Section VII of

this report.

KEYWORDS: SIC 7231 (Beauty shops or salons), sculptured nails, artificial nails, ventilation,

methyl methacrylates, ethyl methacrylates, acetone, benzene

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

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

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

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

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

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

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

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

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

Additional HHE reports are available at http://www.cdc.gov/niosh/hhe/reports
Page 2 - Health Hazard Evaluation Report No. 92-128

II. Introduction

On January 31, 1992, the National Institute for Occupational Safety and Health (NIOSH)

received a request from the Springdale, Ohio Health Department to evaluate exposures to

chemicals used during the application of artificial sculptured nails. The request stated that another

business in the same building had complained of a "terrible odor" emanating from the nail salon. In

response to the request, NIOSH investigators conducted site visits on February 11, 1992,

February 24, 1992, and April 14, 1992. No health effects were noted on the request.

III. Process Description

One or two nail manicurists work in Tina and Angela's Nail Salon at any given time, and

approximately five to twelve sets of nails may be completed on a typical day. A full set of nails

may take up to an hour or more to complete. In many cases, the customer may only request a

polishing and "touch-up," or repair of one or two nails. These procedures take considerably less

time.

Before a sculptured nail can be applied, old color coats are removed and the natural nail surface is

filed to create a rougher surface for better adhesion of the new nail. The natural nail surface is then

sanitized with isopropanol, and an acrylic primer is applied, which also promotes better adhesion.

A removable form is then attached to the fingernail, over which the sculptured nail is formed. The

nail is formed entirely with a small brush applicator, which is dipped first into a liquid monomer,

then dipped into a powder polymer containing a peroxide accelerator. The nail technician then

forms the nail into the general shape before curing (hardening) takes place. 

Further refined shaping takes place after curing by filing. The nail is strengthened with thin

fiberglass fabric. Cuticle oil is usually applied, and the nail is buffed. A base coat of primer is

applied, followed by one or two color coats and a clear protective coat. 

The nail manicurist sits on one side of a small table opposite the customer. Nail sculpturing is

performed approximately 1 to 2 feet below the sculptor's breathing zone. During this time, both

the manicurist and customer are exposed to any organic vapors and methacrylate dust generated

from filing. The manicurist keeps the containers of nail liquid (about 30 ml) covered as much as

possible.

Tina and Angela's Nail salon is located in a single story brick building along with several other

businesses. It is heated by a baseboard heating system located along one of the walls. An air

conditioner has been installed in the south wall of the salon (it does not have an outside air intake). 

The salon does not have a mechanical ventilation system, and the windows in the salon can not be

opened. Fire walls reportedly separate the nail salon from other businesses (there was no common

ceiling plenum). 

The salon uses an Environmental Air System® recirculating floor unit to "filter" vapors in the air (it

was not known when the carbon bed had last been changed). The flow rate through the unit was

unknown.

IV. Industrial Hygiene Investigation

A. Bulk Sample Collection
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Bulk samples of Alpha 9® liquid, NSI Nail® liquid, Alpha 9 Laser Bond Resin®, and

NSI powder® were collected on February 24, 1992. These bulk samples were analyzed

qualitatively by gas chromatography/mass spectrometry (GC/MS). This analytical

technique allows many components of chemical mixtures to be individually identified. The

liquid bulk samples were analyzed directly without any sample preparation. The bulk

powder was extracted with carbon disulfide, which was then analyzed. All analyses were

performed using a 30 meter DB-1 capillary column. The Material Safety Data Sheets

(MSDS) were also available.

B. Air Sampling Methodology

Although Tina and Angela's Nail Salon employees and customers had not complained of

health problems, they agreed to cooperate with the investigation by allowing NIOSH

investigators to collect personal and area samples while nail sculpturing was performed. 

Some of the occupants of adjacent businesses reported detecting transient nail salon

odors. Air sampling was not conducted in the adjacent businesses, because no nail salon

odors were noted during our visit (one business was closed, so the level of odor there

could not be determined). 

Air sampling for methyl and ethyl methacrylate was performed according the NIOSH

method 2537.1 The methacrylate air samples were collected with XAD-2 solid sorbent

tubes (SKC #226-30-06) using low flow Gilian air sampling pumps at flow rates of 20 to

100 milliliters per minute (ml/min). Following sampling, the sorbent tubes were stored on

dry ice until analysis. In the laboratory, the samples were desorbed in 1.0 milliliter (ml)

carbon disulfide (contained 1.0 microliter benzene as an internal standard) and analyzed in

a gas chromatograph using a flame ionization detector (FID).

One full-shift personal sample was collected from the only nail manicurist working on the

day of the NIOSH visit (there were five customers over the course of the day). 

Additionally, one full-shift area sample and eight short-term area samples were collected

on the table where the nail sculpturing was performed. The area samples were located as

close as possible (12 to 20 inches) to the work of the manicurist. 

Air sampling for acetone and benzene was performed according to NIOSH method 1300

with modifications.1 Two full-shift area samples were collected near the table where the

nail sculpturing was conducted. The samples were collected on coconut charcoal tubes

(SKC #226-01) at a flow rate of 100 ml/min using low flow Gilian air pumps. The

samples were desorbed in 1.0 ml carbon disulfide (contained 1.0 microliter n-hexane as an

internal standard) and analyzed in a gas chromatograph using a FID.

V. Evaluation Criteria

The primary sources of environmental evaluation criteria for the workplace are the following: 1)

NIOSH Recommended Exposure Limits (RELs), 2) the Occupational Safety and Health (OSHA)

Permissible Exposure Limits (PELs), and 3) the American Conference of Governmental Industrial

Hygienists (ACGIH) Threshold Limit Values (TLVs).2,3,4 The OSHA standards may be required

to take into account the feasibility of controlling exposures in various industries where the agents

are used; the NIOSH RELs, by contrast, are based primarily on concerns relating to the

prevention of occupational disease.

A time-weighted average (TWA) exposure refers to the average airborne concentration of a
Page 4 - Health Hazard Evaluation Report No. 92-128

substance over the course of a normal 8- to 10-hour workday. Some substances have a shortterm exposure limit (STEL) or ceiling (C) values where there are recognized toxic effects from high

short-term exposures. Environmental evaluation criteria are intended to protect workers

continually exposed up to 40 hours/week for a working lifetime without experiencing adverse

health effects. 

Not all workers will be protected from adverse effects even if their exposures are maintained

below the evaluation criterion. A small fraction may experience health effects as a result of

individual susceptibility, a medical condition, or hypersensitivity (allergy). In addition, some

substances may act in combination with other workplace exposures to produce health effects, even

if the occupational exposures are controlled to a limit set by the evaluation criteria. Some

substances are absorbed by direct contact with the skin and mucous membranes, and thus

potentially increase the overall exposure. Inadvertent oral ingestion can occur occasionally. 

Finally, evaluation criteria may change over the years as new information on the toxic effects of an

agent become available. In evaluating the exposure levels and the recommendations found in this

report, it should be noted that industry is legally required to meet those limits specified by an

OSHA PEL. 

A. Methacrylates

Although methyl methacrylate was banned by the U.S. Food and Drug Administration

(FDA) in 1974 for use in all nail products, there are still many nail products that contain

this chemical.5,6,7,8 Methyl methacrylate was banned because it caused severe irritation

(including dystrophy of the nails) and allergic contact dermatitis in both manicurists and

customers. Many manufacturers of artificial nail products have substituted ethyl or n-butyl

methacrylate as the main component.9 However, these methacrylates have also been

associated with allergic contact dermatitis.10

Overexposure to methyl methacrylate vapor may cause irritation of the nose, throat, and

eyes. The exposure limit was established to prevent complaints of eye and upper

respiratory tract irritation, which have been noted at concentrations of 170 - 250 ppm. 11

High concentrations may cause central nervous system depression and unconsciousness.12

Contact with the skin can cause dermatitis. Headaches and pain in the extremities have

been reported from exposure to the vapor. In addition, handlers of methyl methacrylatecontaining cement have developed parathesias in the fingers. The NIOSH REL for methyl

methacrylate is 100 ppm as a TWA up to 10 hours per day. 2 The OSHA PEL and

ACGIH TLV for methyl methacrylate vapor is 100 ppm as an 8-hour TWA.3,4

There are no occupational criteria for ethyl methacrylate. However, there is evidence that

ethyl methacrylate is toxicologically similar to methyl methacrylate.9,13 Patty's Industrial

Hygiene and Toxicology suggests that industrial hygiene recommendations for methyl

methacrylate can also be applied to the ethyl homologue.14 Both methyl and ethyl

methacrylate are highly flammable. The odor threshold for methyl methacrylate is

approximately 0.2 ppm.15

B. Acetone

Exposure to acetone can cause irritation of the eyes, nose, and throat. Repeated skin

contact can cause dermatitis. At high concentrations, acetone can cause narcosis and

central nervous system (CNS) depression. Acetone is highly flammable and volatile.11,16 
Page 5 - Health Hazard Evaluation Report No. 92-128

The NIOSH REL for acetone is 250 ppm as a TWA up to 10 hours per day. 2 The

OSHA final rule limits and ACGIH TLV are 750 ppm as an 8-hour TWA, and 1000 ppm

as a STEL.3,4 The odor threshold for acetone is approximately 2 ppm.

C. Benzene

In rats, chronic inhalation or oral administration of benzene produced cancers of the liver,

mouth and Zymbal gland. Subchronic inhalation of benzene by rats produced decreased

white blood cell counts and decreased bone marrow cell activity. In humans, chronic

exposure to benzene has produced irreversible injury to the blood-forming organs;12 case

reports and epidemiologic studies indicate a leukemogenic effect in humans.17 Acute

exposures to higher concentrations of benzene can cause irritation of the mucous

membranes and CNS effects.11

NIOSH considers benzene a potential occupational carcinogen. The NIOSH REL for

benzene is 0.1 ppm as an 8-hour TWA with a 1 ppm ceiling.2 The ACGIH considers

benzene a "suspected human carcinogen" and has established a TLV of 10 ppm as an 8-

hour TWA (no STEL); however, it has proposed changing the designation to "confirmed

human carcinogen" and lowering the TLV to 0.1 ppm. The OSHA PEL is 1 ppm as an 8-

hour TWA with a 5 ppm STEL.3,4

D. Ventilation

The American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.

(ASHRAE) has published recommended building ventilation design criteria for different

types of commercial facilities, including beauty shops. ASHRAE Standard 62-1989,

"Ventilation for Acceptable Indoor Air Quality,"18 recommends outdoor air supply rates of

25 cubic feet per minute per person (cfm/person) for beauty shops. ASHRAE also

recommends controlling emission sources. Due to the volatility of the chemicals used in a

salon, the nail operation would probably be a significant emission source.

VI. Results and Discussion

A. Bulk Samples

The major component of the bulk samples (NSI® and Alpha-9® nail liquids) was ethyl

methacrylate; a dimethyl toluidine isomer and traces (less than 0.5%) of methyl

methacrylate were also detected. 

The Alpha-9® Laser Bond Resin consisted primarily of methacrylic acid. Small amounts

of an unknown aromatic nitrogen compound and octabenzone were also detected.

According to the Material Safety Data Sheet (MSDS), the NSI nail powder contains

methyl and ethyl methacrylate polymer, benzoyl peroxide, and titanium dioxide. The

carbon disulfide extract of the powder, analyzed by GC/MS, indicated numerous

compounds, with ethyl methacrylate as a major component. Other substances which were

analyzed included benzene, methyl methacrylate, benzoic acid, biphenyl, various

unidentified aliphatic esters, diethyl phthalate, benzenethiol, diphenyl sulfide, and phenyl

benzoate. The presence of benzene is likely an artifact produced during the GC/MS

analysis. This was confirmed by air samples which were analyzed for benzene (see

discussion below).
Page 6 - Health Hazard Evaluation Report No. 92-128

B. Ethyl and methyl methacrylate

All air samples for methyl methacrylate vapor were non-detected. The limit of detection

(LOD) and limit of quantitation (LOQ) were 0.02 and 0.065 mg/sample, respectively. 

Based on the volume of air sampled, this equates to a LOD ranging from approximately

0.8 to 3.6 ppm methyl methacrylate. 

For ethyl methacrylate, the full-shift personal sample and five of the nine area samples were

below the LOD (see Table 1). Three area samples were between the LOD and the limit

of quantitation (LOQ), and only one area sample was above the LOQ at a concentration

of 7 ppm ethyl methacrylate.

C. Acetone

The two area air samples had low levels of acetone (10 and 6 ppm). These concentrations

of acetone were well below all of the evaluation criteria (250 ppm TWA - NIOSH, 750

ppm - ACGIH and OSHA). The LOD and LOQ for acetone were 0.01 and 0.033

mg/sample, respectively. 

D. Benzene

No benzene vapor was detected on the two area samples. The LOD and LOQ were

0.001 and 0.0033 mg/sample, respectively. Based on the volume of air sampled, this

equates to a LOD of approximately 0.01 ppm.

VII. Recommendations

Many of the chemicals (methacrylates, acetone) used in nail sculpturing emit vapors which have

very low odor thresholds. It is no wonder that adjacent businesses may detect the odor on

occasion. However, these vapors, as measured on the day of the NIOSH survey, do not

constitute a health hazard to the workers or customers at Tina and Angela's Nail Salon or to

adjacent businesses. The most likely potential hazard is contact dermatitis from skin exposure to

methacrylates and other chemicals used in the salon. 

The following recommendations are offered to reduce the potential spread of odors from

the nail salon and provide a more pleasant working environment in the salon.

1. Tina and Angela's Nail Salon should consider installing a mechanical ventilation system that

provides 25 cfm/person outside air, as recommended by ASHRAE. The total quantity of

outside air should be based on the maximum number of customers and employees

expected in the salon at any given time. 

2. To control odor complaints from customers and occupants of adjacent businesses, Tina

and Angela's Nail Salon could consider installing a properly designed exhaust ventilation

system (perhaps a downdraft system). An exhaust ventilation system would also maintain

a slight negative pressure in the salon relative to adjacent areas to prevent the spread of the

odor. NIOSH can provide further guidance if such a system is being considered.

The Environmental Air Systems® recirculating floor unit used to "filter" vapors is not likely

to be very effective because of the low air flow rate through the unit. Furthermore, the unit

may not remove vapors effectively unless the charcoal bed is changed on a regular basis.
Page 7 - Health Hazard Evaluation Report No. 92-128

1. NIOSH [1984]. NIOSH manual of analytical methods, 3rd ed. Cincinnati, OH: U.S.

Department of Health and Human Services, Public Health Service, Centers for Disease

Control, National Institute for Occupational Safety and Health, Division of Physical

Sciences and Engineering. DHHS (NIOSH) Pub. 84-100.

2. NIOSH [1992]. NIOSH Recommendations for occupational safety and health,

compendium of policy documents and statements. Cincinnati, OH: U.S. Department of

Health and Human Services, Public Health Service, Centers for Disease Control, National

Institute for Occupational Safety and Health, Division of Standards Development and

Technology Transfer. DHHS (NIOSH) Publication No. 92-100.

3. Code of Federal Regulations [1989]. Air contaminants--permissible exposure limits. 29

CFR 1910.1000. Washington, DC: U.S. Government Printing Office, Federal Register.

4. ACGIH [1991]. Threshold limit values and biological exposure indices for 1991-1992. 

Cincinnati, OH: American Conference of Governmental Industrial Hygienists.

5. U.S. District Court [1974]. U.S. vs. C.E.B. Products, Inc. 380 Federal Suppl. 664

(N.D. III).

6. Rycroft, RJ [1977]. Contact dermatitis from acrylic compounds. Br J Derm, 96:685-

687.

7. Marks, JG, Bishop ME, Willis WF [1979]. Allergic Contact Dermatitis to Sculptured

Nails. Arch Dermatol. 115:100.

8. Malbach h, Hjorth N, Fregert S, et al [1976]. Butyl methacrylate monomer and ethyl

methacrylate monomer-- frequency of reaction. Contact Dermatitis. 4:60.

9. Hiiakka D, Samimi B [1987]. Exposure to acrylic fingernail sculptors to organic vapors

and methacrylate dusts. Am Ind Hyg Assoc J. 48(3):230-237.

10. Fisher AA [1980]. Cross reactions between methyl methacrylate monomers and acrylic

monomers presently used in acrylic nail preparations. Contact Dermatitis. 6:345-347

11. ACGIH [1986]. Documentation of the threshold limit values and biological exposure

indices, 5th ed. (with updates). Cincinnati, OH: American Conference of Governmental

Industrial Hygienists.

3. The walls (up to the roof) separating the nail salon from adjacent businesses should be

inspected and any gaps should be repaired to reduce the migration of odors.

4. Eating and drinking in the nail salon should not be permitted since unintentional contact of

methacrylate-containing nail liquids on the lips or face could cause allergic contact

dermatitis. Smoking should not be permitted because many of the chemicals used in the

nail salon are very flammable.

VIII. References
Page 8 - Health Hazard Evaluation Report No. 92-128

12. NIOSH/OSHA [1988]. NIOSH/OSHA occupational health guidelines for chemical

hazards. Cincinnati, OH: U.S. Department of Health and Human Service, Public Health

Service, Centers for Disease Control, National Institute for Occupational Safety and

Health and the U.S. Department of Labor, Occupational Safety and Health Administration. 

DHHS (NIOSH) Publication No. 81-123 

13. Oberly R, Tansy MF [1985]. LC50 values for rates acutely exposed to vapors of acrylic

and methacrylic acid esters. Journal of Toxicology and Environmental Health. 16(6):811-

822.

14. Clayton GD, Clayton FE [1981]. Patty's industrial hygiene and toxicology, Volume 2A

(Toxicology), 3rd revised ed. New York: John Wiley & Sons.

15. Plog BA (ed.) [1988]. Fundamentals of industrial hygiene. Chicago, IL: National Safety

Council.

16. NIOSH [1978]. A recommended standard for occupational exposure to ketones. 

Cincinnati, OH: U.S. Department of Health, Education, and Welfare, Public Health

Service, Center for Disease Control, National Institute for Occupational Safety and

Health. DHEW (NIOSH) Publication 78-173.

17. ATSDR [1989]. Toxicological profile for benzene. Atlanta, GA: U.S. Department of

Health and Human Services, Public Health Service, Agency for Toxic Substances and

Disease Registry. DHHS (ATSDR) Publication No. TP-88/03.

18. ASHRAE [1989]. Ventilation for acceptable indoor air quality. Atlanta, GA: American

Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc. ANSI/ASHRAE

Standard 62-1989
Page 9 - Health Hazard Evaluation Report No. 92-128

IX. AUTHORSHIP and ACKNOWLEDGEMENTS

Report Prepared by: John Decker, M.S.

Industrial Hygienist

Atlanta Regional Office

Originating Office: Hazard Evaluations and Technical

 Assistance Branch

Division of Surveillance, Hazard

 Evaluations and Field Studies 

Cincinnati, Ohio 

Field Assistance: Amy Beasley

Chemical Engineer

Division of Physical Sciences

 and Engineering

National Institute for Occupational

 Safety and Health

Cincinnati, Ohio

X. DISTRIBUTION AND AVAILABILITY OF REPORT

Copies of this report may be freely reproduced and are not copyrighted. Single copies of this

report will be available for a period of 90 days after the date of this report from the NIOSH

Publications Office, 4676 Columbia Parkway, Cincinnati, OH 45226. To expedite your request,

include a self-addressed mailing label along with your written request. After this time, copies may

be purchased from the National Technical Information Service (NTIS), 5285 Port Royal Road,

Springfield, VA 22161. Information regarding the NTIS stock number may be obtained from the

NIOSH Publications Office at the Cincinnati address. 

Copies of this report have been sent to:

1. Tina and Angela's Nail Salon

2. Springdale Health Department

3. Occupational Safety and Health Administration, Region V

4. NIOSH Region IV

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

employer in a prominent place accessible to the employees for a period of 30 calendar days.
Table 1

Air Sampling Results for Ethyl Methacrylate

Tina and Angela's Nail Salon

Springdale, Ohio

April 14, 1992

HETA 92-128

Sample Type Sample No. Flow Rate

(ml/min)

Sample Time

(minutes)

Concentration

(ppm)

Personal M1 20 321 ND (LOD = 1)

Area (Cust. #1)

Area 

M2

M3

50

100

46

46

[4]

7

Area (Cust. #2)

Area

M7

M8

50

100

44

44

ND (LOD = 4)

[2]

Area (Cust. #3,4)

Area

M9

M10

50

100

62

62

ND (LOD = 2)

[1]

Area (Cust. #5)

Area

M11

M12

50

100

27

27

ND (LOD = 5)

ND (LOD = 2)

Area M4 20 317 ND (LOD = 1)

The area samples were collected as close as possible to the manicurist (12 to 20 inches away from the

work).

ND = non-detected

LOD = limit of detection

Values in brackets indicate quantities between the LOD and LOQ. These values should be interpreted

with caution, because of unknown accuracy and precision of the analytical method at these low

concentrations.

Limit of Detection (LOD) = 0.03 mg/sample

Limit of Quantitation (LOQ) = 0.072 mg/sample