Formaldehyde 

Exposures During 

Brazilian Blowout Hair 

Smoothing Treatment 

at a Hair Salon – Ohio

Srinivas Durgam, MSPH, MSChE, CIH

Elena Page, MD, MPH

Health Hazard Evaluation Report

HETA 2011-0014-3147

November 2011

DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Disease Control and Prevention

Workplace

Safety and Health

 National Institute for Occupational 

Safety and Health
The employer shall post a copy of this report 

for a period of 30 calendar days at or near 

the workplace(s) of affected employees. The 

employer shall take steps to insure that the 

posted determinations are not altered, defaced, 

or covered by other material during such 

period. [37 FR 23640, November 7, 1972, as 

amended at 45 FR 2653, January 14, 1980].
Health Hazard Evaluation Report 2011-0014-3147 Page i

Report Abbreviations................................................................................................ii

Highlights of the NIOSH Health Hazard Evaluation........................iii

Summary .........................................................................................................v

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

Assessment.....................................................................................................3

Results..............................................................................................................4

Discussion.......................................................................................................6

Conclusions....................................................................................................9

Recommendations.......................................................................................9

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

Contents

Acknowledgments Acknowledgments and Availability of Report................................ 19

Appendix Occupational Exposure Limits and Health Effects......................... 16
Page ii Health Hazard Evaluation Report 2011-0014-3147

Abbreviations

°F Degrees Fahrenheit

ACGIH® American Conference of Governmental Industrial Hygienists

AL Action level

CAS Chemical Abstract Service

CFR Code of Federal Regulations

EPA Environmental Protection Agency

FDA Food and Drug Administration

GA General area

HHE Health hazard evaluation

HVAC Heating, ventilating, and air-conditioning

MSDS Material safety data sheet

NA Not applicable

NAICS North American Industry Classification System

NIOSH National Institute for Occupational Safety and Health

OEL Occupational exposure limit

OSHA Occupational Safety and Health Administration

PBZ Personal breathing zone

PPE Personal protective equipment

PEL Permissible exposure limit

ppm Parts per million

REL Recommended exposure limit

STEL Short-term exposure limit

TLV® Threshold limit value

TWA Time-weighted average

WEELTM Workplace environmental exposure level
Health Hazard Evaluation Report 2011-0014-3147 Page iii

The National Institute for 

Occupational Safety and 

Health (NIOSH) received 

an employer request for a 

health hazard evaluation 

at a hair salon in Ohio. 

The owner was concerned 

about employees’ 

exposure to formaldehyde 

when performing hair 

smoothing treatments 

using Brazilian Blowout® 

hair products.

Highlights of the

NIOSH Health

Hazard Evaluation

What NIOSH Did

● We visited the hair salon on December 13, 2010.

● We looked at work practices and conditions in the salon. We 

also looked at the processes used to apply the hair smoothing 

treatment.

● We took air samples for formaldehyde when no salon 

treatments were being done. We also took air samples when 

the hair smoothing treatment was being applied.

● We took bulk samples of three Brazilian Blowout hair 

products. We analyzed these for formaldehyde.

● We talked with employees about their work practices. We 

also asked them to fill out a survey about any symptoms they 

thought were related to their work.

What NIOSH Found

● Employee exposures to formaldehyde in air exceeded the 

NIOSH and American Conference of Governmental 

Industrial Hygienists’ ceiling limits during the hair 

smoothing treatment.

● The Brazilian Blowout Acai Professional Smoothing Solution 

– Formaldehyde Free Smoothing Formula contained 11% 

formaldehyde, and the Brazilian Blowout Acai Professional 

Anti-Residue Shampoo contained 0.046% formaldehyde. 

The Brazilian Blowout Acai Deep Conditioning Masque 

contained 0.0013% formaldehyde.

● Employees reported no health symptoms during the hair 

smoothing treatment.

● Employees wore disposable latex gloves when applying the 

Brazilian Blowout Acai Professional Smoothing Solution – 

Formaldehyde Free Smoothing Formula to the hair.

What Managers Can Do

● Stop using the Brazilian Blowout Acai Professional 

Smoothing Solution – Formaldehyde Free Formula product.

● Follow the Occupational Safety and Health Administration 

formaldehyde standard if the salon continues to use this hair 

product.
Page iv Health Hazard Evaluation Report 2011-0014-3147

● Tell employees about formaldehyde and its potential hazards 

to their health. Health effects can include cancer, irritation, 

and sensitization of the skin and respiratory system.

● Provide nitrile or butyl rubber gloves to reduce the risk of 

allergic reaction to natural latex.

What Employees Can Do

● Learn more about formaldehyde and how it can affect your 

health.

● Wear either nitrile or butyl rubber gloves when working with 

the Brazilian Blowout hair products.

Highlights of the

NIOSH Health

Hazard Evaluation

 (continued)
NIOSH investigators 

evaluated formaldehyde 

exposures from the 

Brazilian Blowout hair 

products in a hair 

salon. We found that 

employee exposures to 

formaldehyde exceeded 

the NIOSH and ACGIH 

ceiling limits during 

the treatment. The 

Brazilian Blowout Acai 

Professional Smoothing 

Solution – Formaldehyde 

Free Smoothing 

Formula contained 11% 

formaldehyde by weight. 

We recommended that the 

hair salon discontinue the 

use of this product.

Summary

Health Hazard Evaluation Report 2011-0014-3147 Page v

In November 2010, NIOSH received an HHE request from the 

owner of a hair salon in Ohio. The request concerned employee 

exposure to formaldehyde when performing hair smoothing 

treatments using the Brazilian Blowout hair products.

We met with the employer and employee representatives on 

December 13, 2010. We looked at the hair treatment processes, 

work practices, and conditions at the salon. We collected air 

samples for formaldehyde at four locations in the salon when no 

treatment was being conducted. We then collected air samples 

on a hairstylist performing the Brazilian Blowout treatment and 

another hairstylist working in the salon. We collected bulk samples 

of the Brazilian Blowout Acai Professional Smoothing Solution – 

Formaldehyde Free Smoothing Formula, the Brazilian Blowout Acai 

Professional Anti-Residue Shampoo, and the Brazilian Blowout 

Acai Deep Conditioning Masque from their original containers. 

We also talked with employees about their work practices and asked 

them to complete a survey about their symptoms.

The PBZ air sample results for formaldehyde exceeded the NIOSH 

ceiling limit of 0.1 ppm and the ACGIH ceiling limit of 0.3 ppm 

but did not exceed the OSHA STEL of 2 ppm. Bulk sample 

analyses indicated that the Brazilian Blowout Acai Professional 

Smoothing Solution – Formaldehyde Free Smoothing Formula 

contained 11% formaldehyde, and the Brazilian Blowout 

Acai Professional Anti-Residue Shampoo contained 0.046% 

formaldehyde. The Brazilian Blowout Acai Deep Conditioning 

Masque contained 0.0013% formaldehyde. All three employees 

present in the salon on the day of our evaluation completed the 

survey. None of these employees reported symptoms while the 

treatment was being applied, but one did report throat irritation 

when applying the product in the past.

We recommended that the hair salon discontinue the use of 

the Brazilian Blowout Acai Professional Smoothing Solution – 

Formaldehyde Free Formula product. If the salon continues to use 

this product, it should follow the requirements listed in the OSHA 

formaldehyde standard. The employer should also discuss specific 

health hazards associated with formaldehyde with its employees. 

These health hazards include cancer, irritation, and sensitization of 

the skin and respiratory system. Employees should wear nitrile or 

butyl rubber gloves to reduce the risk of an allergic reaction to latex.

Keywords: NAICS 812112 (Beauty Salons), formaldehyde (CAS 

number 50-00-0), hair salon, Brazilian Blowout, smoothing, hair 

treatment, acai
Page vi Health Hazard Evaluation Report 2011-0014-3147

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Health Hazard Evaluation Report 2011-0014-3147 Page 1

Introduction

In November 2010, NIOSH received an HHE request from the 

owner of a hair salon in Ohio. The request concerned hairstylists’ 

exposure to formaldehyde when performing hair smoothing 

treatments with the Brazilian Blowout hair product. We met with 

the employer and employee representatives on December 13, 2010. 

We conducted this evaluation on a day when the hair salon was 

closed. One of the hairstylists was planning to receive the hair 

smoothing treatment, and we used this opportunity to conduct the 

evaluation. Therefore, the two stylists and the salon owner were 

present during the evaluation. The results of this evaluation were 

shared with the employer in an interim letter dated May 16, 2011.

Background

In early 2010 the Oregon Health Sciences University became 

aware that employees of a hair salon in Portland, Oregon, were 

experiencing health symptoms such as difficulty breathing, 

nosebleeds, and eye irritation when using a popular hair 

smoothing product manufactured by Brazilian Blowout. 

Responding to an Oregon Health Sciences University request, 

Oregon OSHA analyzed a bulk sample of the “Formaldehyde 

Free” labeled version of the hair smoothing product and found 

that it contained 8.5% formaldehyde. This discovery led to an 

enforcement initiative by Oregon OSHA and the collection of 

additional bulk samples and air monitoring in Oregon hair salons. 

On the basis of these results, Oregon OSHA issued an alert 

advising salons to take necessary precautions including training 

workers and conducting air monitoring to ensure workers were not 

exposed to formaldehyde levels above the OSHA PEL of 0.75 ppm 

[Oregon OSHA 2010a,b].

Since the alert was issued by Oregon OSHA (October 29, 2010), 

federal OSHA, several state OSHA programs, Health Canada, 

and the U.S. FDA have published alerts and advisories on the use 

of hair smoothing products that contain or release formaldehyde. 

Specifically identified in these reports is the Brazilian Blowout hair 

product line. These alerts and advisories cite a number of studies 

where air sampling measured formaldehyde from hair smoothing 

products that were labeled as “formaldehyde-free” [California 

OSHA 2010; Consumer Federation of America 2011; FDA 2011; 

Health Canada 2011; OSHA 2011].

News reports of health concerns and the presence of formaldehyde 

in keratin-based hair smoothing products such as Brazilian Blowout 
Page 2 Health Hazard Evaluation Report 2011-0014-3147

Introduction

 (continued) were reported as early as 2007 [Fischer 2007; Hayt 2007]. The 

media used these alerts and advisories to highlight the use and 

safety of such products [Pristin 2010; Rabin 2010; Anderson 2011; 

Athavaley 2011a,b; Associated Press 2011].

Process Description

The hair salon was located in a converted single family house. The 

salon had a reception area, hair treatment room, hair wash/dry 

room, and a dispensary room that also served as a break area for 

hairstylists. The dispensary room contained various hair products 

including hair colors, shampoos, and other treatment products 

that were stored in their original containers. The Brazilian Blowout 

Acai Professional Smoothing Solution – Formaldehyde Free 

Smoothing Formula was dispensed into smaller containers in 

this room before being applied to a client’s hair. The hair salon 

had a thermostatically-controlled residential HVAC system in the 

basement. The HVAC system used 1-inch thick pleated fiberglass 

air filters, and the supply air was delivered through floor vents.

This hair salon offered a variety of hair treatments including the 

Brazilian Blowout, one of many commercially available keratinbased hair smoothing treatments. The Brazilian Blowout treatment 

process has six steps:

● Hair was washed with the Brazilian Blowout Acai Professional 

Anti-Residue Shampoo in the hair wash/dry room.

● The hairstylist used a brush to apply the Brazilian Blowout 

Acai Professional Smoothing Solution – Formaldehyde 

Free Smoothing Formula to all parts of the wet hair in a 

systematic fashion in the hair treatment room. The hairstylist 

wore disposable latex gloves during this stage of the treatment 

only (Figure 1).

● Hair was then brushed and blow dried with an Artizen® 3300 

5kV Ionic hair dryer that was set at the highest heat setting.

● A flat iron set at 450°F was used four to five times on each 

section of the hair (Figure 2).

● The Brazilian Blowout Acai Deep Conditioning Masque was 

then applied to the dried hair and rinsed off with water in 

the hair wash/dry room.

● Hair was again blow dried with the same hair dryer in the 

hair treatment room.

Figure 1. Formaldehyde air sampling 

conducted while a hairstylist applies 

Brazilian Blowout smoothing solution to 

the hair.

Figure 2. Flat ironing a section of hair 

– visible smoke was observed during 

this task.
Health Hazard Evaluation Report 2011-0014-3147 Page 3

Assessment

During the visit we discussed the HHE request with the employer, 

the hairstylist conducting the Brazilian Blowout treatment, and the 

hairstylist receiving the treatment. We observed work processes, 

practices, and workplace conditions and spoke with employees. 

We reviewed the MSDS (revision date October 26, 2010) for 

the Brazilian Blowout Professional Smoothing Solution that the 

employer indicated was for the Brazilian Blowout Acai Professional 

Smoothing Solution – Formaldehyde Free Smoothing Formula and 

the treatment summary sheet. MSDSs were not available for the 

Brazilian Blowout Acai Professional Anti-Residue Shampoo nor for 

the Brazilian Blowout Acai Deep Conditioning Masque. We also 

administered questionnaires to employees to assess work-related 

health symptoms.

To evaluate the background levels of formaldehyde in the hair 

salon, we collected GA air samples for formaldehyde at four 

locations throughout the hair salon from 0840–1240 hours when 

no treatments were being conducted. During the Brazilian Blowout 

treatment, we collected PBZ air samples on the hairstylist who 

performed each of the six tasks of the treatment as well as short-term 

samples during specific times within each of the six tasks. We also 

collected a PBZ air sample for formaldehyde on the other hairstylist 

working in the salon. GA air samples were also collected at the same 

four locations used for background samples in the hair salon.

Formaldehyde air samples were collected according to NIOSH 

Method 2016 using silica gel tubes coated with 2,4-dinitrophenyl 

hyrdrazine (Part No. 226-210, SKC Inc., Eighty Four, Pennsylvania) 

and air sampling pumps that were calibrated before and after use 

at flow rates of either 50 or 200 cubic centimeters per minute 

[NIOSH 2011]. These samples were analyzed for formaldehyde 

and other aldehydes including acetaldehyde, benzaldehyde, 

and butyraldehyde, as well as acetone and methyl ethyl ketone. 

The analysis was conducted by high performance liquid 

chromatography according to EPA Method TO-11 [EPA 2011].

We collected bulk samples of the Brazilian Blowout Acai 

Professional Smoothing Solution – Formaldehyde Free Smoothing 

Formula, the Brazilian Blowout Acai Professional Anti-Residue 

Shampoo, and the Brazilian Blowout Acai Deep Conditioning 

Masque from their original containers. These bulk samples were 

analyzed by high performance liquid chromatography using an 

ultraviolet detector as described in the Oregon OSHA report 

[Oregon OSHA 2010a].
Page 4 Health Hazard Evaluation Report 2011-0014-3147

Results

Results of the task-based and short-term PBZ air samples collected 

on the hairstylist performing the Brazilian Blowout treatments 

are presented in Table 1. The formaldehyde concentrations for 

the task-based air samples ranged from 0.018–1.1 ppm. The shortterm sample concentrations ranged from 0.018–1.3 ppm. We 

measured the highest formaldehyde concentration during product 

application (both the task-based and the short-term air samples), 

followed by blow drying and flat ironing. All but two of the shortterm air samples exceeded the NIOSH ceiling limit of 0.1 ppm, 

and four samples exceeded the ACGIH ceiling limit of 0.3 ppm. 

None of the PBZ samples exceeded the OSHA STEL of 2 ppm.

Table 1. PBZ air sampling results for formaldehyde taken on a hairstylist performing the Brazilian Blowout 

smoothing treatment

Task-based Short-term

Task Sampling Time 

(minutes)

Concentration 

(ppm)

Sampling Time 

(minutes)

Concentration 

(ppm)

Hair Washing 10 0.018 9 0.018

Product Application 33 1.1

16 0.36

18 1.3

Blow Drying Post Application 20 0.78 19 0.90

Flat Ironing 20 0.46 16 0.36

Masque Application and Hair 

Wash 11 0.25* 15 0.24

Blow Drying Post Washing 18 0.14 19 0.12

*Backup section collected > 10% of the front section, so concentration may be underestimated.

We collected a PBZ sample on the other hairstylist in the salon, 

and the formaldehyde concentration was 0.10 ppm for a sampling 

period of 112 minutes (the duration of the Brazilian Blowout 

treatment). This hairstylist was cutting hair and conducting other 

salon tasks and was positioned approximately 6 feet from where the 

Brazilian Blowout treatment was being performed.

Results of the GA air sampling for formaldehyde are presented 

in Table 2. When no treatment was performed, the GA air 

concentrations of formaldehyde ranged from 0.0044–0.025 

ppm. The highest formaldehyde concentration (0.025 ppm) was 

measured in the dispensary and may be the result of pouring 

the Brazilian Blowout Acai Professional Smoothing Solution – 

Formaldehyde Free Smoothing Formula from the manufacturer’s 

bottle into a small dish before starting the treatment. When 
Health Hazard Evaluation Report 2011-0014-3147 Page 5

the Brazilian Blowout treatment was performed, the GA air 

concentrations of formaldehyde ranged from 0.057–0.11 ppm, 

with the highest formaldehyde concentration measured in the hair 

treatment room.

Results

 (continued)

Table 2. GA air sampling results for formaldehyde

Area

No Treatment Brazilian Blowout Treatment

Sampling Time 

(minutes)

Concentration 

(ppm)

Sampling Time 

(minutes)

Concentration 

(ppm)

Reception Desk 238 0.0069* 145 0.062

Hair Treatment Room 244 0.0087 144 0.11

Hair Wash/Dry Room 247 0.0044 143 0.057

Dispensary 390 0.025 NA NA

*Backup section collected > 10% of the front section, so concentration may be underestimated.

Acetone, methyl ethyl ketone, and other aldehydes were not 

detected in most of the PBZ and GA air samples. The highest 

air concentrations (acetaldehyde, acetone, benzaldehyde, 

valeraldehyde) were observed during the flat ironing task of the 

treatment but were all less than 1% of the applicable short-term 

OELs.

The Brazilian Blowout Acai Professional Smoothing Solution 

– Formaldehyde Free Smoothing Formula contained 11% 

formaldehyde by weight, and the Brazilian Blowout Acai 

Professional Anti-Residue Shampoo contained 0.046% 

formaldehyde by weight. The Brazilian Blowout Acai Deep 

Conditioning Masque contained 0.0013% formaldehyde by weight, 

a concentration above the limit of detection but below the limit 

of quantitation of 0.0060% of our analytical method; hence this 

reported concentration has uncertainty associated with it.

The three employees present in the salon filled out our 

questionnaire. One applied the treatment, one received the 

treatment, and one was performing other duties. No one reported 

symptoms while the treatment was applied, but one employee 

reported throat irritation when applying the product in the past. 

All reported using latex gloves when applying the treatment.
Page 6 Health Hazard Evaluation Report 2011-0014-3147

Discussion

Employees in hair salons are exposed to a variety of chemicals 

that are constituents of the products used in the trade [Labreche 

et al. 2003; Mendes et al. 2011]. Some of these ingredients, 

including formaldehyde, have been found to be carcinogenic by 

the International Agency for Research on Cancer [Labreche et al. 

2003]. Formaldehyde (CAS number 50-0-0) is a colorless gas at 

room temperature and is known and marketed in products under 

various names, including methanal, methylene oxide, formalin, and 

methylene glycol [NIST 2011]. (Note: the CAS number is a unique 

identifier assigned to chemicals.) Formaldehyde in a solution of 

water containing alcohol stabilizer is referred to as formalin and 

has the same CAS number of 50-0-0. However, formaldehyde 

when dissolved in water forms a diol called methylene glycol or 

methane diol, which has a different CAS number of 463-57-0. 

Formaldehyde gas and the methylene glycol solution exist in a 

dynamic and reversible equilibrium, and therefore, the aqueous 

solution is capable of releasing formaldehyde gas [Winkelman et al. 

2002; Oregon OSHA 2010a; Consumer Federation of American 

2011]. An Oregon OSHA report concluded that for the purposes 

of worker protection it is appropriate to refer to both the hydrated 

and the non-hydrated formaldehyde as formaldehyde [Oregon 

OSHA 2010a]. In addition, the OSHA formaldehyde standard 

applies to all occupational exposures to formaldehyde (i.e., 

formaldehyde gas) its solutions, and other materials that release 

formaldehyde [29 CFR 1910.1048].

In this evaluation we intended to measure employee exposures 

during each hair treatment task while simultaneously collecting 

shorter-term (approximately 15-minute) air samples for comparison 

with applicable OELs. However, during our evaluation we learned 

that the duration of each hair treatment task depended on 

factors such as the client’s hair length and the hairstylist’s skill 

level. For this evaluation the duration of all of the hair treatment 

tasks (except product application) was short, resulting in similar 

sampling times for both the task and short-term air samples. 

Because in other hair treatments this may not necessarily be the 

case, we believe it would be helpful to continue collecting both 

task-based and short-term air samples.

Our PBZ air sampling results showed that the hairstylist using 

the Brazilian Blowout Acai Professional Smoothing Solution 

– Formaldehyde Free Smoothing Formula was exposed to 

formaldehyde air concentrations that exceeded the NIOSH 

ceiling limit during all Brazilian Blowout treatment tasks except 
Health Hazard Evaluation Report 2011-0014-3147 Page 7

Discussion

 (continued) the initial hair wash. The ACGIH ceiling limit was exceeded 

during the product application, blow drying post application, 

and flat ironing tasks of the treatment. None of the reported 

formaldehyde concentrations exceeded the OSHA PEL or OSHA 

STEL. These results are consistent with the Oregon OSHA 

findings from its evaluation of seven salons that used the same 

“formaldehyde free” product [Oregon OSHA 2010a]. However, 

federal OSHA test results have shown that formaldehyde levels 

in a hair salon have exceeded the OSHA OELs when hairstylists 

use the Brazilian Blowout Acai Professional Smoothing Solution 

– Formaldehyde Free Smoothing Formula [OSHA 2011]. OSHA 

provided recommendations to limit worker exposures, including 

using air ventilation systems to keep formaldehyde levels below 

OSHA’s exposure limits, performing regular maintenance on these 

systems to ensure proper operation, and using lower heat settings 

on flat irons and blow dryers [OSHA 2011]. Use of local exhaust 

ventilation in hair salons has been documented to reduce exposure 

levels to contaminants when compared to salons with no local 

exhaust ventilation [Hollund and Moen 1998].

The GA air sample results suggest that hairstylists and other salon 

employees (especially those working near the treatment) can be 

exposed to formaldehyde air concentrations during the Brazilian 

Blowout treatment above background levels. Further sampling 

is needed to characterize their full-shift personal exposures to 

formaldehyde.

We found that the Brazilian Blowout Acai Professional Smoothing 

Solution – Formaldehyde Free Smoothing Formula contained 

11% formaldehyde by weight, which is similar to the average 

formaldehyde content of 8.8% reported by Oregon OSHA for the 

same “formaldehyde free” product [Oregon OSHA 2010a]. We also 

found that the Brazilian Blowout Acai Professional Anti-Residue 

Shampoo contained 0.046% formaldehyde, which is similar to the 

0.05% average formaldehyde content reported by Oregon OSHA 

for this same shampoo [Oregon OSHA 2010a].

Because we found formaldehyde air concentrations greater than 

0.1 ppm, and the Brazilian Blowout Acai Professional Smoothing 

Solution – Formaldehyde Free Smoothing Formula contained 

formaldehyde at greater than 0.1%, the hazard communication 

requirements of the OSHA formaldehyde standard are applicable 

[29 CFR 1910.1048(m)]. This standard requires employers to 

discuss specific health hazards with their employees including 
Page 8 Health Hazard Evaluation Report 2011-0014-3147

Discussion

 (continued) cancer, irritation, and sensitization of the skin and respiratory 

system. The standard also requires a written hazard communication 

program that includes requirements for MSDSs and employee 

training.

The OSHA formaldehyde standard requires that manufacturers 

provide their downstream users (such as hairstylists) with accurate 

MSDSs that address health hazards associated with exposure to 

formaldehyde. In addition, manufacturers are required to modify 

their labels to indicate the presence of formaldehyde in their 

product. If the product is capable of releasing formaldehyde at 

levels exceeding 0.5 ppm over an 8-hour work shift, the label shall 

contain the words “Potential Cancer Hazard.”

The MSDS provided by the manufacturer to the hair salon for the 

product it uses (the Brazilian Blowout Acai Professional Smoothing 

Solution – Formaldehyde Free Smoothing Formula) stated that 

it contained less than 5% methylene glycol. However, this MSDS 

did not state specifically that it was for the Formaldehyde Free 

Smoothing Formula. We contacted the product manufacturer 

directly to inquire whether the Brazilian Blowout Professional 

Smoothing Solution MSDS was for the “Formaldehyde Free 

Smoothing Formula” used by the hair salon during our 

evaluation and to request MSDSs for the Brazilian Blowout Acai 

Professional Anti-Residue Shampoo and Brazilian Blowout Acai 

Deep Conditioning Masque. We received MSDSs for all three 

products but none of the product names on the MSDSs were 

the same as the product labels. However, we were assured by the 

manufacturer that they were correct [Dalva 2011]. In addition, 

the “Formaldehyde Free” portion of the product label has been 

removed. The MSDSs for the Brazilian Blowout Acai Professional 

Anti-Residue Shampoo and Brazilian Blowout Acai Deep 

Conditioning Masque listed no hazardous components.

The hair salon should be aware that salon product MSDSs may 

not list formaldehyde as being present or may list formaldehyde 

under other names such as methylene glycol, methane diol, 

formalin, methylene oxide, paraform, formic aldehyde, methanal, 

oxomethane, oxymethylene, or CAS Numbers 50-00-0 and 463-57-0.
Health Hazard Evaluation Report 2011-0014-3147 Page 9

Conclusions

The hairstylist performing hair smoothing treatment with the 

Brazilian Blowout Acai Professional Smoothing Solution – 

Formaldehyde Free Formula product was exposed to formaldehyde 

air concentrations that exceed the NIOSH and ACGIH ceiling 

limits.

Recommendations

On the basis of our findings, we recommend the actions listed 

below to create a more healthful workplace. We encourage the 

hair salon to use a labor-management health and safety committee 

or working group to discuss the recommendations in this report 

and develop an action plan. Those involved in the work can best 

set priorities and assess the feasibility of our recommendations for 

the specific situation at the hair salon. Our recommendations are 

based on the hierarchy of controls approach (refer to the Appendix: 

Occupational Exposure Limits and Health Effects). This approach 

groups actions by their likely effectiveness in reducing or removing 

hazards. In most cases, the preferred approach is to eliminate 

hazardous materials or processes and install engineering controls 

to reduce exposure or shield employees. Until such controls are 

in place, or if they are not effective or feasible, administrative 

measures and/or personal protective equipment may be needed.

Elimination and Substitution

Elimination or substitution of a toxic/hazardous process material 

is a highly effective means for reducing hazards. Incorporating this 

strategy into the design or development phase of a project, commonly 

referred to as “prevention through design,” is most effective because it 

reduces the need for additional controls in the future.

● Stop using the Brazilian Blowout Acai Professional 

Smoothing Solution – Formaldehyde Free Formula because 

salon employees can be overexposed to formaldehyde.

Engineering Controls

Engineering controls reduce exposures to employees by removing 

the hazard from the process or placing a barrier between the 

hazard and the employee. Engineering controls are very effective 

at protecting employees without placing primary responsibility of 

implementation on the employee.
Page 10 Health Hazard Evaluation Report 2011-0014-3147

Recommendations

● Use local exhaust ventilation to reduce employee’s 

formaldehyde exposures to below the applicable OELs if 

Brazilian Blowout hair smoothing product use continues 

despite our recommendation.

Administrative Controls

Administrative controls are management-dictated work practices and 

policies to reduce or prevent exposures to workplace hazards. The 

effectiveness of administrative changes in work practices for controlling 

workplace hazards is dependent on management commitment and 

employee acceptance. Regular monitoring and reinforcement are 

necessary to ensure that control policies and procedures are not 

circumvented in the name of convenience or production.

If the salon continues to use the Brazilian Blowout hair product it 

should:

● Follow the requirements listed in the OSHA formaldehyde 

standard [29 CFR 1910.1048]. These requirements include 

use of personal protective equipment, employee training, 

availability of eye and skin washing equipment, and employee 

medical surveillance.

● Conduct air sampling to further characterize employee 

exposures to formaldehyde.

▪ If air sampling results show formaldehyde 

concentrations above the OSHA PEL, AL, or STEL 

follow the requirements as described in the OSHA 

formaldehyde standard. Review the OSHA hazard 

alert to identify different ways of reducing employee 

exposure to formaldehyde [OSHA 2011].

▪ If sampling results show formaldehyde 

concentrations above the NIOSH ceiling limit 

or other OELs, provide employees with the 

appropriate NIOSH-approved respirator for use 

until engineering or administrative controls can be 

implemented to reduce formaldehyde exposures 

below the OELs. Respirators must be used in 

the context of a complete respiratory protection 

program in accordance with the OSHA Respiratory 

Protection Standard [29 CFR 1910.134].
Health Hazard Evaluation Report 2011-0014-3147 Page 11

Recommendations

 (continued) Personal Protective Equipment

PPE is the least effective means for controlling employee exposures. 

Proper use of PPE requires a comprehensive program, and calls 

for a high level of employee involvement and commitment to be 

effective. The use of PPE requires the choice of the appropriate 

equipment to reduce the hazard and the development of 

supporting programs such as training, change-out schedules, and 

medical assessment if needed. PPE should not be relied upon as 

the sole method for limiting employee exposures. Rather, PPE 

should be used until engineering and administrative controls can 

be demonstrated to be effective in limiting exposures to acceptable 

levels.

● Provide employees nitrile or butyl rubber gloves rather than 

latex gloves because of the risk of allergic reaction to natural 

rubber latex.
Page 12 Health Hazard Evaluation Report 2011-0014-3147

References

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products. The Associated Press. [http://safecosmetics.org/article.

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Athavaley A [2011a]. The taming of the curl. Wall Street Journal. 

[http://online.wsj.com/article/SB100014240527487044613045762

16470789970688.html]. Date accessed: September 2011.

Athavaley A [2011b]. Call for FDA to regulate hair straighteners. 

Wall Street Journal. [http://online.wsj.com/article/SB1000142

4052748703421204576327583570589222.html]. Date accessed: 

September 2011.

California OSHA [2010]. Hair smoothing products that may 

contain or release formaldehyde. [http://www.dir.ca.gov/dosh/

HairSmoothingPageVersion1Nov182010.pdf]. Date accessed: 

September 2011.

CFR. Code of Federal Regulations. Washington, DC: U.S. 

Government Printing Office, Office of the Federal Register.

Consumer Federation of America [2011]. Consumers and hair care 

professionals should be cautious when using or applying “keratinbased” hair smoothing products. [http://consumerfed.org/pdfs/

CIR-hair-smoother-press-release.pdf]. Date accessed: September 

2011.

Dalva G [2011]. Brazilian Blowout – MSDS. Private e-mail message 

to Srinivas Durgam (sdurgam@cdc.gov), May 10.

EPA [2011]. EPA air toxics method – monitoring methods. [http://

www.epa.gov/ttnamti1/airtox.html]. Date accessed: September 

2011.

FDA [2011]. FDA receives complaints associated with the 

use of Brazilian Blowout. [http://www.fda.gov/Cosmetics/

ProductandIngredientSafety/ProductInformation/ucm228898.

htm]. Date accessed: September 2011.

Fischer MA [2007]. Scared straight. Allure the beauty expert. 

[http://www.allure.com/beauty-trends/how-to/2007/scared_

straight]. Date accessed: September 2011.
Health Hazard Evaluation Report 2011-0014-3147 Page 13

References 

(continued) Hayt E [2007]. Curls, splits! Ringlets, be gone! New York Times. 

[http://www.nytimes.com/2007/07/19/fashion/19skin1.html]. 

Date accessed: September 2011.

Health Canada [2011]. Several professional hair smoothing 

solutions contain excess levels of formaldehyde. [http://www.hc-sc.

gc.ca/ahc-asc/media/advisories-avis/_2011/2011_56-eng.php]. 

Date accessed: September 2011.

Hollund BE, Moen BE [1998]. Chemical exposures in hairdresser 

salons: effect of local exhaust ventilation. Ann Occup Hyg 

42(4):277–281.

Labreche F, Forest J, Trottie M, Lalonde M, Simard R [2003]. 

Characterization of chemical exposures in hairdressing salons. App 

Occup Environ Hyg 18(12):1014–1021.

Mendes A, Madureira J, Neves P, Carvalhais C, Laffon B, Teixeira 

JP [2011]. Chemical exposure and occupation symptoms among 

Portuguese hairdressers. J Tox Env Health, Part A 74(15–16):993–

1000.

NIOSH [2011]. NIOSH manual of analytical methods (NMAM®). 

4th ed. Schlecht PC, O’Connor PF, eds. Cincinnati, OH: U.S. 

Department of Health and Human Services, Centers for Disease 

Control and Prevention, National Institute for Occupational Safety 

and Health, DHHS (NIOSH) Publication 94-113 (August 1994); 

1st Supplement Publication 96-135, 2nd Supplement Publication 

98-119; 3rd Supplement 2003-154. [http://www.cdc.gov/niosh/

docs/2003-154/]. Date accessed: September 2011.

NIST [2011]. Formaldehyde. National Institute for Standards 

and Technology Standard Reference Database 69: NIST 

Chemistry Web Book. [http://webbook.nist.gov/cgi/cbook.

cgi?ID=C50000&Units=SI]. Date accessed September 2011.

Oregon OSHA [2010a]. “Keratin-based” hair smoothing products 

and the presence of formaldehyde. [http://www.orosha.org/pdf/

Final_Hair_Smoothing_Report.pdf]. Date accessed: September 

2011.

Oregon OSHA [2010b]. Oregon OSHA reiterates caution to salons 

using hair-smoothing products. [http://www.orosha.org/admin/

newsrelease/2010/nr2010_28.pdf]. Date accessed: September 2011.
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(continued) OSHA [2011]. Hazard alert – hair smoothing products that could 

release formaldehyde. [http://www.osha.gov/SLTC/formaldehyde/

hazard_alert.html]. Date accessed: September 2011.

Pristin T [2010]. A safety kink in hair relaxing. New York Times. 

[http://www.nytimes.com/2010/11/04/fashion/04SKIN.html]. 

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Rabin RC [2010]. Safety: scrutiny for hair–straightening treatment. 

New York Times. [http://www.nytimes.com/2010/10/12/health/

research/12safety.html]. Date accessed: September 2011.

The Associated Press [2011]. U.S. warns against Brazilian blowout. 

New York Times. [http://www.nytimes.com/2011/04/13/

us/13brfs-USWARNSAGAIN_BRF.html]. Date accessed: 

September 2011.

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Jansen LPBM [2002]. Kinetics and chemical equilibrium of the 

hydration of formaldehyde. Chem Eng Sci 57(19):4067–4076.
Health Hazard Evaluation Report 2011-0014-3147 Page 15

Appendix: Occupational Exposure Limits and Health Effects

In evaluating the hazards posed by workplace exposures, NIOSH investigators use both mandatory (legally 

enforceable) and recommended OELs for chemical, physical, and biological agents as a guide for making 

recommendations. OELs have been developed by federal agencies and safety and health organizations to 

prevent the occurrence of adverse health effects from workplace exposures. Generally, OELs suggest levels 

of exposure that most employees may be exposed to for up to 10 hours per day, 40 hours per week, for a 

working lifetime, without experiencing adverse health effects. However, not all employees will be protected 

from adverse health effects even if their exposures are maintained below these levels. A small percentage 

may experience adverse health effects because of individual susceptibility, a preexisting medical condition, 

and/or a hypersensitivity (allergy). In addition, some hazardous substances may act in combination with 

other workplace exposures, the general environment, or with medications or personal habits of the 

employee to produce adverse health effects even if the occupational exposures are controlled at the level set 

by the exposure limit. Also, some substances can be absorbed by direct contact with the skin and mucous 

membranes in addition to being inhaled, which contributes to the individual’s overall exposure.

Most OELs are expressed as a TWA exposure. A TWA refers to the average exposure during a normal 8- 

to 10-hour workday. Some chemical substances and physical agents have recommended STEL or ceiling 

values where adverse health effects are caused by exposures over a short period. Unless otherwise noted, 

the STEL is a 15-minute TWA exposure that should not be exceeded at any time during a workday, and 

the ceiling limit is an exposure that should not be exceeded at any time.

In the United States, OELs have been established by federal agencies, professional organizations, state 

and local governments, and other entities. Some OELs are legally enforceable limits, while others are 

recommendations. The U.S. Department of Labor OSHA PELs (29 CFR 1910 [general industry]; 29 

CFR 1926 [construction industry]; and 29 CFR 1917 [maritime industry]) are legal limits enforceable 

in workplaces covered under the Occupational Safety and Health Act of 1970. NIOSH RELs are 

recommendations based on a critical review of the scientific and technical information available on a 

given hazard and the adequacy of methods to identify and control the hazard. NIOSH RELs can be found 

in the NIOSH Pocket Guide to Chemical Hazards [NIOSH 2010]. NIOSH also recommends different 

types of risk management practices (e.g., engineering controls, safe work practices, employee education/

training, personal protective equipment, and exposure and medical monitoring) to minimize the risk of 

exposure and adverse health effects from these hazards. Other OELs that are commonly used and cited 

in the United States include the TLVs recommended by ACGIH, a professional organization, and the 

WEELs recommended by the American Industrial Hygiene Association, another professional organization. 

The TLVs and WEELs are developed by committee members of these associations from a review of the 

published, peer-reviewed literature. They are not consensus standards. ACGIH TLVs are considered 

voluntary exposure guidelines for use by industrial hygienists and others trained in this discipline “to assist 

in the control of health hazards” [ACGIH 2011]. WEELs have been established for some chemicals “when 

no other legal or authoritative limits exist” [AIHA 2011].

Outside the United States, OELs have been established by various agencies and organizations and 

include both legal and recommended limits. The Institut für Arbeitsschutz der Deutschen Gesetzlichen 

Unfallversicherung (IFA, Institute for Occupational Safety and Health of the German Social Accident 
Page 16 Health Hazard Evaluation Report 2011-0014-3147

Appendix: Occupational Exposure Limits and Health Effects

 (continued)

Insurance) maintains a database of international OELs from European Union member states, Canada 

(Québec), Japan, Switzerland, and the United States. The database, available at http://www.dguv.de/ifa/

en/gestis/limit_values/index.jsp, contains international limits for over 1,500 hazardous substances and is 

updated periodically.

Employers should understand that not all hazardous chemicals have specific OSHA PELs, and for some 

agents the legally enforceable and recommended limits may not reflect current health-based information. 

However, an employer is still required by OSHA to protect its employees from hazards even in the absence 

of a specific OSHA PEL. OSHA requires an employer to furnish employees a place of employment free 

from recognized hazards that cause 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, NIOSH investigators encourage 

employers to make use of other OELs when making risk assessments and risk management decisions to 

best protect the health of their employees. NIOSH investigators also encourage the use of the traditional 

hierarchy of controls approach to eliminate or minimize identified workplace hazards. This includes, in 

order of preference, the use of (1) substitution or elimination of the hazardous agent, (2) engineering 

controls (e.g., local exhaust ventilation, process enclosure, dilution ventilation), (3) administrative controls 

(e.g., limiting time of exposure, employee training, work practice changes, medical surveillance), and (4) 

personal protective equipment (e.g., respiratory protection, gloves, eye protection, hearing protection). 

Control banding, a qualitative risk assessment and risk management tool, is a complementary approach 

to protecting employee health that focuses resources on exposure controls by describing how a risk 

needs to be managed. Information on control banding is available at http://www.cdc.gov/niosh/topics/

ctrlbanding/. This approach can be applied in situations where OELs have not been established or can be 

used to supplement the OELs, when available.

Below we provide the OEL and a discussion of the potential health effects from exposure to formaldehyde.

Formaldehyde

Under the OSHA general industry standard for airborne exposure to formaldehyde [29 CFR 1910.1048], 

the PEL is 0.75 ppm for an 8-hour TWA, the AL is 0.5 ppm for an 8-hour TWA, and the STEL is 2 ppm 

for a 15-minute TWA. The standard requires medical surveillance for employees exposed to formaldehyde 

at or above the AL or STEL.

The NIOSH REL for formaldehyde is 0.016 ppm for up to an 8-hour TWA. NIOSH also has a 15-minute 

ceiling limit of 0.1 ppm that is not to be exceeded during a work shift [NIOSH 2010]. NIOSH recognized 

formaldehyde as a potential occupational carcinogen in 1981 and, following the NIOSH carcinogen policy 

in existence at the time, set the REL to the “lowest feasible concentration,” which for formaldehyde was 

defined as the analytical limit of quantification of 0.016 ppm for up to 8 hours [NIOSH 1981]. Since 

then, experience has shown that this REL is actually not the “lowest feasible concentration” because 

formaldehyde in the ambient air can exceed 0.016 ppm, a fact later acknowledged by NIOSH [Lemen 

1987]. Additionally, the subsequent revision of the NIOSH carcinogen policy [NIOSH 1995], combined 
Health Hazard Evaluation Report 2011-0014-3147 Page 17

Appendix: Occupational Exposure Limits and Health Effects 

 (continued)

with better exposure characterization and advances in risk assessment and management strategies, support 

the need for NIOSH to reassess the formaldehyde REL. This effort is in progress.

The ACGIH lists formaldehyde as a sensitizer and has a ceiling limit of 0.3 ppm [ACGIH 2011]. An 

ACGIH ceiling limit is an exposure that should not be exceeded at any time during the work shift.

The most commonly reported and best documented health complaints due to exposure to low 

concentrations of formaldehyde include irritation of the eyes, nose, and throat; nasal congestion; 

headaches; skin rash; and asthma. It is often difficult to attribute specific health effects to particular 

concentrations of formaldehyde because some people may have symptoms at levels where others may 

experience no symptoms. For example, irritant effects may occur in some people exposed to formaldehyde 

at concentrations below 0.10 ppm, but more typically irritation may not occur until exposures are at 

levels of 1.0 ppm or greater. However, individuals with pre-existing allergies or respiratory disease and 

people who have become sensitized from prior exposure may experience symptoms due to exposure to 

concentrations of formaldehyde between 0.05 and 0.10 ppm [NRC 1981]. Formaldehyde is also a skin 

sensitizer [Markowitz 2005]. In addition, the International Agency for Research on Cancer classifies 

formaldehyde as a human carcinogen (group 1) on the basis of associations between formaldehyde 

exposure and nasopharyngeal cancer and leukemia [Baan et al. 2009]. NIOSH considers formaldehyde as 

a potential occupational carcinogen; ACGIH lists formaldehyde as a suspected human carcinogen; and 

the U.S. Department of Health and Human Services lists formaldehyde as reasonably anticipated to be a 

human carcinogen in its 11th report on carcinogens [NIOSH 1981; ACGIH 2011; DHHS 2011].

References

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agents and biological exposure indices. Cincinnati, OH: American Conference of Governmental 

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AIHA [2011]. AIHA 2011 Emergency response planning guidelines (ERPG) & workplace environmental 

exposure levels (WEEL) handbook. Fairfax, VA: American Industrial Hygiene Association.

Baan R, Grosse Y, Straif K, Secretan B, El Ghissassi F, Bouvard V, Benbrahim-Tallaa L, Guha N, Freeman 

C, Galichet L, Cogliano V, on the behalf of the WHO International Agency for Research on Cancer 

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accessed: November 2011.
Page 18 Health Hazard Evaluation Report 2011-0014-3147

Appendix: Occupational Exposure Limits and Health Effects 

 (continued)

Lemen RA [1987]. Official letter of February 9, 1987, from R.A. Lemen, Director, Division of Standards 

Development and Technology Transfer, National Institute for Occupational Safety and Health, U.S. 

Department of Health and Human Services, Cincinnati, OH to Tom Hall, Docket Office, Department of 

Labor, Washington, DC.

Markowitz S [2005]. Chemicals in the plastics, synthetic textiles, and rubber industries. In: Rosenstock 

L, Cullen MR, Brodkin CA, Redlich CA, eds. 2nd ed. rev. Textbook of clinical occupational and 

environmental medicine. Philadelphia, PA: Elsevier Saunders, pp. 1008–1029.

NIOSH [1981]. Current intelligence bulletin 34 – formaldehyde: evidence of carcinogenicity. Cincinnati, 

OH: U.S. Department of Health and Human Services, Centers for Disease Control, National Institute for 

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statements. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease 

Control and Prevention, National Institute for Occupational Safety and Health.

NIOSH [2010]. NIOSH pocket guide to chemical hazards. Cincinnati, OH: U.S. Department of Health 

and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational 

Safety and Health, DHHS (NIOSH) Publication No. 2010-168c. [http://www.cdc.gov/niosh/npg/]. Date 

accessed: September 2011.

NRC [1981]. Formaldehyde and other aldehydes. National Research Council (National Academy 

Press), Washington, DC. [http://www.archive.org/stream/formaldehydeando003763mbp/

formaldehydeando003763mbp_djvu.txt]. Date accessed: September 2011.
Page 19

The Hazard Evaluations and Technical Assistance Branch 

(HETAB) of the National Institute for Occupational Safety and 

Health (NIOSH) conducts field investigations of possible health 

hazards in the workplace. These investigations are conducted 

under the authority of Section 20(a)(6) of the Occupational Safety 

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

the Secretary of Health and Human Services, following a written 

request from any employer or authorized representative of 

employees, to determine whether any substance normally found 

in the place of employment has potentially toxic effects in such 

concentrations as used or found. HETAB also provides, upon 

request, technical and consultative assistance to federal, state, and 

local agencies; labor; industry; and other groups or individuals to 

control occupational health hazards and to prevent related trauma 

and disease.

Mention of any company or product does not constitute 

endorsement by NIOSH. In addition, citations to websites 

external to NIOSH do not constitute NIOSH endorsement of 

the sponsoring organizations or their programs or products. 

Furthermore, NIOSH is not responsible for the content of these 

websites. All Web addresses referenced in this document were 

accessible as of the publication date.

This report was prepared by Srinivas Durgam and Elena Page 

of HETAB, Division of Surveillance, Hazard Evaluations and 

Field Studies.Analytical support was provided by Bureau Veritas 

North America. Industrial hygiene equipment and logistical 

support was provided by Donald Booher and Karl Feldmann. 

Health communication assistance was provided by Stefanie Evans. 

Editorial assistance was provided by Ellen Galloway. Desktop 

publishing was performed by Greg Hartle.

Copies of this report have been sent to employee and management 

representatives at the hair salon, the state health department, 

and the Occupational Safety and Health Administration 

Regional Office. This report is not copyrighted and may be freely 

reproduced. The report may be viewed and printed at http://

www.cdc.gov/niosh/hhe/. Copies may be purchased from the 

National Technical Information Service at 5825 Port Royal Road, 

Springfield, Virginia 22161.

Health Hazard Evaluation Report 2011-0014-3147

Acknowledgments and

Availability of Report
NIOSH [2011]. Health hazard evaluation report: formaldehyde exposures 

during Brazilian Blowout hair smoothing treatment at a hair salon – Ohio. 

By Durgam S, Page E. Cincinnati, OH: U.S. Department of Health and Human 

Services, Centers for Disease Control and Prevention, National Institute for 

Occupational Safety and Health, NIOSH HETA No. 2011-0014-3147.

To receive NIOSH documents or information about 

occupational safety and health topics, contact NIOSH at:

1-800-CDC-INFO (1-800-232-4636)

TTY: 1-888-232-6348

E-mail: cdcinfo@cdc.gov

or visit the NIOSH web site at: www.cdc.gov/niosh.

For a monthly update on news at NIOSH, subscribe to 

NIOSH eNews by visiting www.cdc.gov/niosh/eNews.

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Safety and Health