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OFFICE OF CHEMICAL SAFETY

AND POLLUTION PREVENTION

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

 

June 28, 2010

MEMORANDUM

Subject: Occupational and Residential Exposure and Risk Assessment for the 

New Active Ingredient N, N’-methylenebis (5-methyloxazolidin) 

(Stabicide 71)

From: Timothy C. Dole, CIH, Industrial Hygienist

Risk Assessment and Science Support Branch (RASSB)

Antimicrobials Division (7510P)

Through: Timothy Leighton, Senior Scientist

Risk Assessment and Science Support Branch (RASSB)

Antimicrobials Division (7510P)

And

Nader Elkassabany Ph.D., Chief

Risk Assessment and Science Support Branch (RASSB)

Antimicrobials Division (7510P)

To: Dennis Edwards, Chief

Marshall Swindell, Product Manager, Team 33

Regulatory Management Branch I

Antimicrobials Division (7510P)

DP Barcodes: D360880

Chemical: N,N’-methylenebis (5-methyloxazolidin) 

PC Code: 114804

Registrant: Schulke & Mayr GmbH

The Antimicrobial Division’s (AD) Regulatory Management Branch I has requested that 

the Risk Assessment and Science Support Branch (RASSB) conduct exposure and risk 

assessments to evaluate the application for registration of Stabicide 71, which contains a new 

active ingredient N,N’-methylenebis (5-methyloxazolidin). 
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Executive Summary

Stabicide 71 (i.e. N, N’-methylenebis -5-(methyloxazolidin)) is proposed for use as a 

preservative to control non-public health bacteria and some fungi in metal working fluids, 

water based drilling muds and diesel fuels. It is anticipated that workers will experience 

dermal and inhalation exposure to Stabicide 71 and it’s degradate, formaldehyde, as a result 

of these uses.

The toxicology database for Stabicide 71 includes an acute dermal toxicity study, three 

mutagenecity studies, an oral prenatal developmental study in rabbits and a 90 oral toxicity 

study in rats. Because the database is limited and does not include inhalation or dermal 

studies, endpoints could not be selected for risk assessment for these routes of exposure. 

These endpoints will be selected once the required studies are submitted and reviewed.

Hydrolysis data indicates N, N’-methylenebis (5-methyloxazolidin) degrades to

formaldehyde with a half life of less than one hour (US EPA, 2010), therefore, the risk of

formaldehyde inhalation exposure was also assessed. To assess non-cancer risks, an 

inhalation RfC of 0.1 ppm (i.e. 100 ppb) was derived from a NOAEL of 0.1 ppm for peak 

exposures that was selected from literature studies where respiratory irritation was observed 

in workers exposed to formaldehyde. Cancer risks were assessed using a unit risk of 1.3 x 

10-5per ug/m3from IRIS and results of CIIT model runs as presented in Conolly et. al. 2004.

There are no exposure data available for Stabicide 71 for machining operations. Based on 

the exposure data for a related chemical, HHT, however, it is likely that formaldehyde 

exposures resulting from the use of Stabicide 71 in MWF will exceed the level of concern of 

100 ppb. The exact magnitude of these exceedances cannot be predicted from the available 

data because the sampling times generally ranged from 3 to 4 hours while peak exposures are 

normally measured with sampling times of 15 minutes or less. Since many of these results 

exceed the level of concern of 100 ppb as a 3 to 4 hour average; however, it can be assumed 

that 15 minute samples taken within the same 3 to 4 hour time period would have also 

exceeded 100 ppb. It is also possible that the 3 to 4 hour samples which were below 100 ppb 

contained one or more 15 minute periods of exposure that exceeded 100 ppb. 

Handlers will be exposed to formaldehyde during the addition of Stabicide 71 to drilling 

muds and diesel fuels. There are no exposure data available for Stabicide 71 for these 

scenarios. The intensity of these exposures will depend upon the method of addition and the 

configuration of the process. If Stabicide 71 is added by open pouring into an open process 

with minimal engineering controls, then formaldehyde exposures could exceed the RfC of 

100 ppb. Conversely, if Stabicide 71 is added using closed system transfer to processes that 

have engineering controls to prevent emissions, then it is possible that formaldehyde

exposures would not exceed 100 ppb. 

If workplace conditions are maintained such that peak exposures do not exceed 0.1 ppm, 

daily average exposures will be at least 3 times less than 0.1 ppm because workplace 

exposures from even the most well controlled processes have a within day variability of at 

least 3. If it assumed that workers are exposed to averaged daily concentration of 0.03 ppm 

for 240 days per year and 35 years per 70 year lifetime, the cancer risk ranges from 

2.2 x 10-8to 5.8 x 10-5depending upon which calculation method is used (IRIS or CIIT). 
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1.0 Product Use Profile:

Stabicide 71 is a formaldehyde releasing preservative that contains a new active 

ingredient, N,N’-methylenebis (5-methyloxazolidin) at a purity of 99.09% a.i. It is proposed 

for use as a preservative to control non-public health bacteria and some fungi in metal 

working fluids, water based drilling muds and diesel fuels. The application rates are 500 to 

2000 ppm for all three uses though a lower use rate of 50 to 200 ppm is also listed for 

preventive treatment of diesel fuel.

2.0 Summary of Toxicological Endpoints:

Because N,N’-methylenebis (5-methyloxazolidin) is a formaldehyde releaser, the toxicity 

of both the parent compound and the formaldehyde that is released from the parent compound 

must be considered. 

2.1 N,N’-methylenebis (5-methyloxazolidin)

A summary of the toxicity data that has been submitted for N,N’-methylenebis (5-

methyloxazolidin) is included in D360405 (EPA, 2009). These studies include an acute 

dermal toxicity study, three mutagenecity studies, an oral prenatal developmental study in 

rabbits and a 90 oral toxicity study in rats. There are no inhalation or dermal studies 

available for N,N’-methylenebis (5-methyloxazolidin). D360405 also includes a listing of 

the studies that are required for the registration of N,N’-methylenebis (5-methyloxazolidin), 

and this list includes dermal and inhalation toxicity studies. Endpoints will be selected for 

risk assessment upon receipt and review of these studies.

2.2 Formaldehyde

Hydrolysis data indicates N, N’-methylenebis (5-methyloxazolidin) degrades to

formaldehyde with a half life of less than one hour (US EPA, 2010). This degradation 

occurs through a number of steps and includes the formation of Hexahydro-1,3,5-tris (2-

hydroxypropyl)-s-triazine.

Table 1.0 summarizes the toxicological endpoints for formaldehyde which are described 

in more detail in following memorandum: "Formaldehyde/Paraformaldehyde - Report of the 

Antimicrobials Division Toxicity Endpoint Selection Committee (ADTC)” from T. McMahon 

to S. Carlisle, dated June 24, 2008. Endpoints were selected only for assessing inhalation 

exposures to formaldehyde and it was determined that assessments of the other routes of 

exposure (dietary, dermal and incidental oral) would not be not required. In addition, the 

following disclaimer from the “Response to Public Comments on the Formaldehyde 

Preliminary Risk Assessment RED” from T. McMahon and T. Dole to S. Carlisle, dated 

January, 6, 2009 is provided for the non-cancer formaldehyde endpoint:

OPP developed the formaldehyde inhalation non-cancer toxicological endpoint used in this 

document through the established registration process, which includes stakeholder 

consultation and public comment. However, the result has not been subjected to an interagency review or external peer review. Because of time constraints imposed by statutory 

deadline, OPP could not consider all available peer reviewed science (for example, the 

intentional human dosing toxicity studies). Thus, this value should be considered an interim 

value, developed solely for the purposes of this determination and subject to future revision 

and subsequent peer review and should not be used in other contexts as EPA's opinion of the 

best available science on the non-cancer effects of formaldehyde. 
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For the purposes of this assessment, the formaldehyde endpoints are expressed as RfCs 

which are the NOAEL divided by the uncertainty factor (UF). The UF is 1 for the 

occupational exposures because the NOAEL was derived from observational studies of 

workers exposed to formaldehyde and the UF is 10 for the residential exposures to account 

for the increased sensitivity of some members of the residential population. It is also 

important to note these RfCs are for peak exposures.

The range of potential cancer risks were bracketed using the biologically based CIIT 

model (Conolly, 2004) and the upper bound cancer risks from IRIS reflecting default linear 

extrapolation. The CIIT model cancer risks were taken from Table 8 of Conolly, 2004.

Table 1 - Summary of Toxicological Doses and Endpoint Selection for Formaldehyde 

Exposure

Scenario

Dose Used in 

Risk Assessment

Reference Concentration 

(RfC)

Study and Toxicological Effects

Inhalation

(all durations) NOAEL (human) 

= 100 ppb

RfCoccupational = 100 ppb

RfCresidential= 10 ppb

Where:

RfC = NOAEL

 UF

UF = 1 for occupational

UF = 10 for residential

ACGIH 2001, TLV Documentation for 

Formaldehyde

Horvath, E.P. et al. (1986): JAMA 259(5): 701-

707. Based on complaints of eye, nose, and throat 

irritation in particle board workers at 

formaldehyde concentrations of 0.4 – 1.0 ppm. 

Redden, J. (2005): Section 18 Emergency 

Exemption for the use of Paraformaldehyde: U.S. 

Army Medical Research Institute of Infectious 

Diseases.

Cancer Lifetime extra cancer unit risk estimate of 1.3  10-5

per g/m3(US EPA IRIS 

http://www.epa.gov/ncea/iris/subst/0419.htm) 

And

CIIT modeling: Tables 8A (for residential) and B (for professional). Hockey stick-shaped CRCP 

(nonsmoking) (Conolly, 2004)

2.3 Comparison to Other Formaldehyde Endpoints

The Occupational Health and Safety Administration (OSHA) issued the formaldehyde 

standard as a final rule on May 27, 1992. This standard includes a Permissible Exposure 

Limit (PEL) for formaldehyde of 0.75 ppm as an eight hour time weighted average (TWA) 

and 2 ppm as a 15 minute short term exposure (STEL). This means that 8 hour TWA 

formaldehyde exposures cannot exceed 0.75 ppm and 15 minute exposures cannot exceed 2 

ppm. Since 1992, the American Conference of Governmental Hygienists (ACGIH) has 

recommended a threshold limit value (TLV) of 0.3 ppm as a ceiling (C) value. A TLVCeiling is an exposure limit that should not be exceeded at any time during the workday and 

is normally assessed as a 15 minute exposure. According to ACGIH “The recommended 

TLV-Ceiling of 0.3 ppm for workplace air formaldehyde is based on evidence of irritation 

from reports of occupational exposure to formaldehyde as well as human formaldehyde 

exposures in other settings. This recommended TLV may not eliminate all worker 

complaints of sensory irritation associated with exposure to this chemical. However, ACGIH 

believes that the 0.3 ppm ceiling value should result in a significant reduction of complaints 

currently associated with exposure to formaldehyde”. 
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3.0 Exposure Assessment for Non-Cancer Risks

Because the proposed uses Stabicide 71 are limited to industrial environments, only the 

occupational RfC of 100 ppb is applicable to exposure assessment for non-cancer risks. 

There are three occupational exposure scenarios that involve the use of Stabicide 71. These 

scenarios include: (1) Metal Working Fluid Treatment, (2) Drilling Mud Treatment and (3) 

Diesel Fuel Storage Tank Treatment.

3.1 Metal Working Fluid Exposures

Contram ST-1 is proposed for use in metal working fluids (MWF) at a maximum rate of 

2000 ppm and this use will likely result in exposures to formaldehyde. Since formaldehyde

has a significant vapor pressure (1 mm Hg at 25 C as formaldehyde in formalin), the vapor 

inhalation exposure is the primary route of exposure. Inhalation exposure to the vapor is 

considered to be representative of exposure to the MWF aerosols containing formaldehyde as 

well as formaldehyde vapors that evaporate from MWF.

Exposure Data 

No data have been submitted regarding the potential formaldehyde exposures during the 

use of MWFs treated with Stabicide 71. There are data available, however, from two studies 

on Hexahydro-1,3,5-tris(2-hydroxyethyl)-s-triazine (HHT) which is closely related to 

Hexahydro-1,3,5-tris(2-hydroxypropyl)-s-triazine which is a degradate of Stabicide 71 (US 

EPA, 2010). These studies were reviewed by AD in memo D345082 of June 30, 2008

and summaries are included below:

Cohen, 1994

This study was conducted at a triazine formulation facility and at seven different 

manufacturing facilities that used triazine to treat metal working fluids (MWF). The 

manufacturing facilities included steel rolling mills, automotive transmission plants, 

industrial machinery manufacturers, an automobile manufacture and two aluminum can 

manufacturers. Personal breathing zone (PBZ) air samples were collected on the workers as 

they conducted normal production operations such as tool setup, machining, grinding, steel 

rolling and aluminum can drawing and ironing using MWF treated with triazine. Samples 

were also taken during the addition of triazine which typically occurred in the middle of the 

shift. Area samples were taken in the work areas near the employees and source samples 

were taken near potentially high exposure areas such as MWF sumps and return flumes. 

Background samples were also taken in areas such as adjacent office spaces to determine 

ambient formaldehyde levels that were not associated with MWF operations. Metal working 

fluid samples were taken from the sumps at each facility before and after triazine addition 

and were analyzed for triazine. 

The PBZ samples were collected either with SKC silica gel tubes and/or GMD 570 

passive badge dosimeters both of which were treated with 2, 4-dinitrophenylhydrazine 

(DNPH). In many cases duplicate samples were taken using both methods. The samples 

were taken for 120 to 240 minutes each during MWF operations before and after triazine 

addition and for 5 to 27 minutes during triazine addition. Area, source and background 

samples were also collected also using midget impingers operated at a flow rate of 1 LPM in 

addition to the silica gel tubes and passive dosimeters. The tube samples were analyzed 

using EPA Method #T011 and the impinger samples were analyzed using NIOSH Method 
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#3500. The badge samples were analyzed by eluting acetonitrile and analyzing with HPLC 

and UV detection. The limit of quantification (LOQ) for a 4 hour sample was 17 ppb, 18 

ppb and 27ppb for the impingers, tubes and badge dosimeters, respectively. The LOQ for a 

15 minute sample was 270 ppb, 297 ppb and 426 ppb.

Field recovery samples were generated by spiking with known amounts of a solution of 

one microgram formaldehyde per microliter of water to approximate the quantities expected 

from a four hour sample at 100 ppb. The results indicated generally good recoveries with the 

exception of the badge dosimeters from site 3B which indicated an excessive recovery of 

272%. This recovery was greater than the recovery of 103 % from site 3A or the average 

recovery of 113 % from all of the sites combined. There were only a few recoveries that 

were less than 90% and these include the two badge spikes from site 1 (58% and 64%) and 2 

tube spikes from site 4 (67% and 80%).

A summary of the PBZ and background sample results is included in Table 2. The 

results for the production operations ranged from non-detect to a maximum of 490 ppb and 

many exceeded the 100 ppb level of concern. The highest results were from Site 3B which 

had good ventilation and few worker complaints. The PBZ samples for triazine addition are 

not included in the table because they were all less than the LOQ which ranged from 165 ppb 

to 930 ppb due the short sampling times. The background samples ranged from non-detect to 

118 ppb with the highest levels measured at sites 5 and 7. 

Table 2 - Formaldehyde PBZ Air Concentrations Measured on Workers 

Using Triazine Treated MWF 

Site Operation MWF Triazine 

Level (ppm)

N Duration

(Minutes)

Reported Values 

(ppb)

Background 

Level (ppb)

1 Charging Reactor

Drumming Triazine

N/A 1

1

80

264

130 

28

Not 

Measured

2A Operator and Helper 550, 1240 6 182 to 223 <19 to <35 <20

2B Operator and Helper 0, 220 5 179 to 223 <21 to 110 <20

3A Heat Treat Operator

Lathe Operator

Grinder

Machining Operator

0, 400 1

1

6

7

117,174

127,172

110 to 172

109 to 166

<26, <55

<26, <36

<37 to <58

<28 to <56

<18

3B Machining Operator

Maintenance Helper

Pipefitter

1300, 1400 8

2

3

144 to 212

206, 146

47 - 223

140 to 490

250, 410

140 - 340

<18

4A Worker in General Area

Machinery Operator

1045,1685 2

1

162-242

211,161

52, 106

154,257

28

4B Machinery Operators 1045, 1685 6 153 to 236 102 to 163 28

5 Grinder Operators

Machine Operators

586 to 1107 4

10

171 to 220

189 to 218

110, 130

55 to 250

78

6A Machine Operator

Setup Operator

169, 1894 4

4

160, 236

236, 237

<18, 160

<18, 140

26

6B Grinder Operator 301, 1847 4 175 to 208 <30 to 58 26

7 D& I Operator

Washer Operator

997, 1160 8

2

195 to 277

194, 284

123 to 196

175, 127

118

8 D & I Operator Line 1 975, 1823 2 421 to 464 123 to 209 50

* Results highlighted in bold font exceed 100 ppb
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Linnainmaa, 2003

This study was conducted in 8 workplaces where hard metal or stellite blades were 

ground and 10 workplaces where general machining operations, such as grinding, turning, 

drilling, sawing and milling, were done. Seven different types of recirculating local exhaust 

ventilation systems were tested by measuring endotoxin concentrations in the exhaust air 

during the normal operation of the machines. Both personal and area samples were collected 

for formaldehyde using Waters Sep Pak silica cartridges treated with DNPH at a flow rate of 

0.1 LPM for 2 to 4 hours. The concentration of triazine in the MWF was also measured in 

conjunction with the air sampling. 

Twenty one personal samples were collected and the formaldehyde air concentrations 

ranged from 8.1 ppb to 179 ppb with a mean of 42 ppb and a median of 20 ppb. Twenty 

seven area samples were collected and the air concentrations ranged from 6.5 ppb to 195 ppb 

with a mean of 45 ppb and a median of 17 ppb. The concentrations of triazine in the MWF 

ranged from <0.5 to 3500 ppm with a mean of 470 ppm. The concentrations of triazine in the 

MWF correlated well with the formaldehyde concentrations in the air near the machines 

(n=23) with a correlation coefficient (R) of 0.69. The authors concluded that the triazine 

levels should be kept above 500 ppm to prevent bacterial growth and that overdosing should 

be avoided to keep airborne formaldehyde levels low.

Machining Operations Exposure Assessment

Based on the exposure data from the Cohen and Linnainmaa studies it is likely that 

formaldehyde exposures resulting from the use of Stabicide 71 in MWF will exceed the level 

of concern of 100 ppb, which is expressed as a peak value. The exact magnitude of the 

exceedance cannot be predicted from the available data because the sampling times generally 

ranged from 3 to 4 hours while peak exposures are normally measured with sampling times 

of 15 minutes or less. Since many of these results exceed the level of concern of 100 ppb as a 

3 to 4 hour average; however, it can be assumed that 15 minute samples taken within the 

same 3 to 4 hour time period would have also exceeded 100 ppb. It is also possible that the 3 

to 4 hour samples which were below 100 ppb contained one or more 15 minute periods of 

exposure that exceeded 100 ppb. 

3.2 Drilling Mud Exposures

Exposure to formaldehyde can occur during the addition of Stabicide 71 to drilling muds. 

Because formaldehyde has a high vapor pressure (1.0 mm Hg in formalin), the inhalation unit 

exposure data from PHED and CMA are not applicable because these data are based upon 

chemicals that have a much lower vapor pressure (less than 1.0 x 10-4 mm Hg). When the 

vapor pressure is less than 1.0 x 10-4mm Hg, chemicals are airborne primarily as aerosols, 

while at a higher vapor pressure, chemicals are airborne primarily as vapors. 

There are no exposure data available for Stabicide 71 for drilling mud operations; 

however, the exposures to oil mist and vapor resulting from the use of oil based drilling muds 

during off-shore drilling has been extensively studied in Norway (Steinsvag et al., 2006). 

This study indicated that rig type, technical control measures, and mud temperatures 

significantly determined exposure to oil mist while rig type, base oil type, base oil viscosity, 

work area and mud temperature and season determined exposure to oil vapor. The technical 
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control measures mainly included cabins for the operators, more efficient ventilation systems 

and closing mud pits and fluids lines. Additional data regarding exposures to other 

contaminants including formaldehyde from biocides are included a related study (Steinsvag 

et al., 2007). According to the 2007 study, formaldehyde levels measured in the workers 

breathing zone ranged from 0.06 to 0.29 ppm (n=6) while formaldehyde levels in area 

samples ranged from 0.05 to 0.53 ppm (n=10). These samples were merged from two reports. 

One report was from 1999 where sampling was done when filling biocide during water 

injection on an installation and a second report from 2000 includes sampling work at a 

biocide unit at another installation. No other details regarding these reports were included in 

the article and it is not known which formaldehyde containing or releasing biocide was used.

3.3 Diesel Fuel Storage Tank Treatment

Stabicide 71 is proposed for use as a preservative in diesel fuel contained within storage 

tanks. The intensity of worker exposure for this use will depend upon the method of addition 

and the configuration of the tanks. If Stabicide 71 is added by open pouring into the hatch of

a tank that has minimal engineering controls, then formaldehyde exposures could exceed the 

level of concern of 100 ppb. Conversely, if Stabicide 71 is added using closed system 

transfer to tanks that have engineering controls to prevent emissions, then it is possible that 

formaldehyde exposures would not exceed 100 ppb; however, air monitoring data would be 

needed to verify this conclusion.

4.0 Exposure Assessment for Cancer Risks

If workplace conditions are maintained such that peak exposures do not exceed 0.1 ppm, 

8 hour daily average exposures will be at least 3 times less than 0.1 ppm because workplace 

exposures from even the most well controlled processes have a within day variability of at 

least 3. If it assumed that workers are exposed to averaged daily concentration of 0.03 ppm

for 240 days per year and 35 years per 70 year lifetime, the cancer risk ranges from 

2.2 x 10-8to 5.8 x 10-5depending upon which calculation method is used (IRIS or CIIT). 

Table 4 – Occupational Cancer Risks for Exposure to Formaldehyde

Average Daily 

Concentration

(8 hour TWA)

Days Exposed 

per Year

Years 

Exposed per 

Lifetime

Life Time 

Average Daily 

ConcentrationA

IRIS 

Cancer 

RiskB

CIIT 

Cancer 

RiskC

0.03 ppm /41 ug/m3

240/365 35/70 4.5 ug/m3

5.8 x 10-52.2 x 10-8

A. LADC = Average Daily Concentration (ug/m3) * (8/24)*(240/365) *(35/70)

B. IRIS Cancer Risk = LADC (ug/m3) * IRIS Unit Risk (1.3 x 10-5per ug/m3)

C. CIIT Cancer Risk is taken from Table 8, Part B of Conolly et al., 2004 (Light work, Hockey stick CRCP, nonsmoking). 

 It is based on the 8 hour TWA, 5 days per week of exposure and exposures for 40 years of an 80 year lifetime.

5.0 Human Studies Considerations

All of the exposure studies mentioned in this risk assessment (Cohen, 1994, Linnainmaa, 

2003, Steinsvag et al., 2006 and Steinsvag et al., 2007) have been determined by the OPP 

ethics reviewers to be observational in nature and did not involve intentional exposure to 

human subjects.
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6.0 References

Cohen, 1994. “A Study of Formaldehyde Exposures from Metalworking Fluid Operations 

Using Hexahydro-1,3,5-Tris (2-Hydroxyethyl)-S- Triazine, MRID 473354-02, H. J. Cohen, 

University of New Haven, May 3, 1994

Conolly, R. B., Kimbell, J.S., Janszen, D., Scholsser, P. M., Kalisak, D., Preston, J., and 

Miller, F.J. 2004. Human Respiratory Tract Cancer Risks of Inhaled Formaldehyde: DoseResponse Predictions Derived From Biologically-Motivated Computational Modeling of a 

Combined Rodent and Human Dataset. Toxicological Sciences: 82 (279-296). 

Linnainmaa, 2003. “Control of Worker’s Exposure to Airborne Endotoxins During Use of 

Metalworking Fluids”, Markuu Linnainmaa, Hannu Kivirata, Juha Laitinen and Sirpa 

Laitinen, Kuopio Regional Institute of Occupational Health and National Public Health 

Institute Department of Environmental Health, Kupio, Finland, AIHA Journal 64:496-5000, 

July/August 2003.

Steinsvag et al., 2006. “Exposure to Oil Mist and Oil Vapour During Offshore Drilling in 

Norway, 1979-2004”, K. Steinsvag, M. Bratveit and B. Moen, University of Bergen, Ann. 

Occupational Hygiene, Volume 50, Number 2, pp. 109-122, 2006.

Steinsvag et al., 2007. “Exposure to Carcinogens for Defined Job Categories in Norway’s 

Offshore Petroleum Industry, 1970 to 2005”, K. Steinsvag, M. Bratveit and B. Moen, 

University of Bergen, Ann. Occupational Environmental Medicine, Volume 64, pp. 250-258, 

2007.

US EPA, 2009. Toxicology Study Requirements (Scoping) and Toxicology Study Review of 

N, N’-methylenebis (5-methyloxazolidin). Memorandum from Steve Malish to Marshall 

Swindell and Demson Fuller, D360405, June 17, 2009

US EPA, 2010. Environmental Fate Assessment of Stabicide 71 and Requests for 

Metalworking Fluids and Offshore Oilfield Use in Drilling Muds where Release in Water 

will Occur. Memorandum from James Breithaupt to Dennis Edwards and Marshall Swindell, 

D360401, May 24, 2010.

Sign-off Date: 06/28/10

DP Barcode: D360880