2 

1. Executive summary 

The Environmental Fate and Effects Division (EFED) has completed the preliminary problem 

formulation for the ecological risk, environmental fate, endangered species, and drinking water 

assessments to be conducted as part of the registration review of furfural. Furfural is a broadspectrum pesticide exhibiting a relatively high volatility potential, used in foliar applications to 

various turf and ornamentals. The problem formulation describes the methods planned to be 

used during the completion of drinking water and ecological risk assessments in support of 

registration review and provides an overview of the environmental fate, ecological effects, and 

potential risks associated with the use of furfural as well as uncertainties unique to risk 

assessment of furfural. This document also identifies additional studies that would be beneficial 

to the conduct of an ecological risk assessment. Major findings include: 

Environmental Fate Uncertainties and Study Requests 

New aerobic soil and anaerobic soil metabolism studies were required as part of the conditional 

registration of furfural. The available studies, which have been deemed supplemental, provide 

limited information, or there is uncertainty, with respect to the formation of major transformation 

products of furfural: furfuryl alcohol and 2-furoic acid. Despite these uncertainties, the studies 

were used in the previous screening-level assessments of the new uses on turf and ornamentals, 

sod farms and athletic fields. In order to address this uncertainty, the requested studies should 

closely monitor the transformation products in addition to the parent compound, and avoid 

problems observed in the previous studies. They should supply appropriate data about the fate 

and persistence of furfural and its transformation products, resulting in a better characterization 

and understanding of the metabolism of this chemical. The data will be used in re-estimating the 

input parameters to be used in the aquatic exposure models. Three aerobic and four anaerobic 

soils are required. In the absence of the additional data, EFED may make conservative 

assumptions about the persistence of furfural and its degradates in soil systems. The available 

studies provide only limited information and certain assumptions were needed in previous 

assessments. 

 

Additionally, there is lack of knowledge about the fate and persistence of furfural and its 

transformation products in water bodies impacting aquatic organisms. In previous assessments, 

the aerobic aquatic metabolism input value was derived from the aerobic soil metabolism studies. 

Knowledge of the persistence of furfural and furfuryl alcohol in aerobic aquatic environments is 

needed. 

There are also uncertainties related to the biodegradation of furfural occurring beneath the top 

soil. This may be an important process impacting potential furfural exposure in ground water 

sources to evaluate drinking water exposure.

Therefore, the following are environmental fate studies that are being requested at this time to 

support the preliminary risk assessment for Registration Review: 
3 

 835.4100 Aerobic Soil Metabolism1 and 835.4200 Anaerobic Soil Metabolism: 

 835.4300 Aerobic Aquatic Metabolism: 

 Non-guideline Laboratory Investigation of Subsurface Degradation Study 

Please refer to Section 12a for further details on the justification addressing the need for these 

studies. 

Ecological Effects Uncertainties and Data Requests

A substantial amount is known about the potential for adverse effects to non-target terrestrial and 

aquatic animals and plants. However, there are still some uncertainties, in part due to the lack of 

honeybee vapor phase toxicity test and vegetative vigor vapor phase toxicity test. EFED presumes 

risk due to these routes of exposure and effect types, in the absence of data. 

 

There are sources of uncertainty in the estimation of risks to birds and mammals through dietary 

exposure to furfural on treated foliage and other dietary items, in addition to the lack of avian 

dietary studies. The requirement for passerine acute oral and avian reproduction studies were 

waived in response to a prior waiver requests. The rationale in the passerine acute oral and avian 

reproduction waiver requests (DP Barcodes D410714 and D399351 respectively) indicate the 

tests would not realistically replicate exposure of furfural in the field due to the transient nature 

of furfural. The estimated risks herein are driven by the relatively high application rates of 

furfural, which are beyond the range that the T-REX model is considered to have been fully 

evaluated. The concentrations on foliage and prey items are also expected to be transient in 

nature, due to the volatility of this compound and application of large amounts of water. 

Information on foliar dissipation of this compound appropriate for modeling with T-REX is 

limited. A soil half-life (of 1 day) is used, in part since birds and other wildlife can probe in the 

soil for food. Because both acute and chronic risks in T-REX are based on peak concentrations, 

the risk quotients calculated by T-REX do not reflect the expected transient nature of this 

compound. Residues on turf are requested as part of requested field dissipation studies (see 

above Environmental Fate and Exposure data requests). 

Acute and chronic aquatic exposures are possible, in part due to repeated or continuous input to 

the aquatic environment. Data on the acute toxicity of furfural to the mysid shrimp would help 

reduce uncertainty since the current study was conducted with larvae that were 5 days old rather 

than <24 hours old as recommended by the guidelines. 

The ecological toxicity data requirements for aquatic and terrestrial organisms is largely 

complete. However, there are a few data gaps listed below which are requested at this time:

850.1035 Estuarine/Marine Acute Toxicity- Shrimp: This study (MRID 46426508) is 

currently considered Supplemental. If data that indicates that 5 day old mysids are in fact 

more susceptible than <24 hour old mysids to Furfural, this study may be upgraded to 

 

1

 Study MRID No. 49583601 is currently in review. This study may be used to fulfill the data request, but 

determination of this is pending. Therefore, the request for the aerobic soil metabolism study still exists at this time. 
4 

Acceptable. In addition, data indicating that all test mysids completed at least one complete 

molt cycle during the 96 hour exposure should also be submitted. 

Non-Guideline Vegetative Vigor Vapor-Phase Toxicity Study: Furfural is a highly volatile 

chemical and used in quantities that may result in exposure to terrestrial plants via off-site 

transport in the vapor phase. 

Non-guideline Laboratory Investigation acute vapor phase toxicity study with the honey 

bee: The current estimate of terrestrial invertebrate risk relies on estimated acute contact toxicity 

with the honeybee. This study will enable a vapor phase risk assessment specific to bees since 

furfural is a volatile chemical with multiple applications per season. 

Please refer to Section 12b for further details on the justification addressing the need for these 

studies. 

2. Introduction 

EFED evaluated the most recent ecological risk assessments for furfural in association with the 

updated toxicity, exposure, and usage information to determine if sufficient data are available 

and if further updates are needed to support registration review. Recent risk assessments include 

the Section 3 for the first outdoors uses on turf and ornamentals (DP Barcode 346394+, April 5, 

2010), the Section 3 new use on athletic fields (DP Barcode D389908, dated 01/17/2012), and 

the Section 3 new use on ornamentals and clarification on existing uses on turf2 (DP Barcode 

D389903, dated 05/07/2012). In addition, EFED considered the latest Agency science policies 

and risk assessment methodologies. The structure of furfural, as well as the chemical names and 

other identifiers can be found in the chemical identity table attached to this document (Appendix 

A). 

3. Use Characterization 

Furfural is a heterocyclic aromatic aldehyde. It is a colorless, oily liquid with an almond-like 

odor. Furfural’s is used to control nematodes and fungi. Furfural reportedly destroys the 

nematode cuticle, causing it to die by dehydration or attack by parasites. “Furfural interacts with 

the cuticle of the nematode, effectively stripping the protective layers which result in the cuticle 

swelling and disintegrating. Movement of the nematode is impeded and it subsequently dies 

through dehydration or attack by parasitic organisms.”3

 The mode of action for control of fungi 

is not known. 

Furfural is formulated in one active end-use product as an emulsifiable concentrate (Multiguard 

Protect EC, EPA Reg. No. 75753-1). It is used on turf golf courses (e.g., tees, greens, fairways, 

and roughs), sod farms, athletic fields, field grown plants and ornamentals (e.g. cut flower 

 

2

 Although the uses on turf and ornamentals had been previously assessed, only the use on turf had been approved 

after the 2010 assessment. 

3

 Burger, G.J. An overview of the development of furfural (Crop Guard®) as a nematicide in South: The chemistry 

of furfural within the soil and agricultural environment. (Published in the Internet). 
5 

production, production nurseries, residential and commercial landscapes, and similar areas), and 

greenhouse use pre- and post-plant on ornamentals. The maximum seasonal application rate is 

417 lbs. a.i./A/season with a maximum of six applications at 69.4 lbs. a.i./A per treatment, with 

14 days minimum between treatments, although furfural may also be applied as a spot treatment 

in the greenhouse with a 7 day minimum retreatment interval and an unspecified number of 

applications during the growing season. It is applied in foliar application to turf grass and 

ornamentals using conventional ground sprayers, or via drenches or chemigation. Watering-in is 

a required practice for all furfural applications; it moves the product into the soil for efficacy and 

also reduces or delays volatilization. Furfural applied to turf must be watered-in through 6 

inches depth (according to the label), via irrigation. For field grown plants, ornamentals, and 

indoor greenhouse plant and ornamentals, applications may be made via tubes or drip tapes. For 

potted plants, furfural is applied either as a pre-plant or post-plant drench, in irrigation water/ 

fertilizing solution, with spray boom or overhead irrigation systems, or via spot treatment, 

utilizing a low pressure backpack sprayer (greenhouses only). EFED will use application 

scenarios that result in maximum exposure scenarios for a given use for the risk assessment. 

Any absence of information on the labels that specifies the maximum single application rate, the 

application interval, the annual maximum rate allowed (lbs. a.i./year), or application method may 

result in conservative assumptions. 

4. Conclusions from Previous Risk Assessments 

a. Ecological Risk Assessment 

The Agency has conducted multiple ecological risk assessments on furfural that serve as a basis 

for this scoping document, including the Section 3 for the first outdoors uses on turf and 

ornamentals, the Section 3 new use on athletic fields, and the Section 3 new use on ornamentals 

and clarification on existing uses on turf4. Based on current furfural uses, the primary risk issues 

have been identified for aquatic animals and aquatic plants, which is consistent with its use as an 

herbicide. The risk findings are summarized in Table 1 below. 

Table 1. Summary of Risk Concerns Identified for Furfural in Previous Assessments

Birds Mammals Terr. 

Plants 

Terr. 

Inverts Fish BCF Aquatic Inverts 

Aquatic 

Plants 

Groundwater 

Contamination 

Degradates 

of Concern 

Noa Noa No No Yes No Yes Yes Yes 

Yes – 

Furfuryl 

Alcohol 

a No reproduction data were available to allow for a chronic risk assessment 

Yes = at least one LOC has been exceeded in previous assessments; “No” = LOCs have not been exceeded in 

previous assessments; NA = RQs have not been calculated previously. 

b. Drinking Water Exposure Assessments 

 

4

 Although the uses on turf and ornamentals had been previously assessed, only the use on turf had been approved 

after the 2010 assessment. 
6 

While drinking water assessments have been conducted addressing the various existing turf and 

ornamental uses for furfural, there has also been much on-going work and consultation to 

address drinking water exposure for other proposed bare soil uses with the Health Effects 

Division (HED). Furthermore, HED recently identified the need to conduct a cancer assessment 

for furfural and it’s degradate furfuryl alcohol addressing all routes of exposure, including 

drinking water. Therefore, EFED recently conducted an updated analysis consistent with current 

EFED policies and modeling tools related to ground water exposure (e.g., PRZM-GW model). 

The recent findings identify exposure from surface water drinking water sources as the driver 

behind acute exposure and ground water sources as the driver behind chronic and cancer 

exposure, both resulting from existing furfural surface spray and chemigation turf and 

ornamental applications (applied at 69.4 lbs. a.i./A with 6 applications and 14 days minimum 

between treatments). However, this latest analysis was provided informally and is subject to 

change pending future label revisions. A formal drinking water assessment will be finalized 

based on furfural’s regulatory status at the time that the Preliminary Registration Review Risk 

Assessment is conducted. 

5. Environmental Fate and Transport 

The physicochemical characteristics of furfural are presented in Table 2. 

Table 2. Selected Physicochemical Properties for Furfural.

Parameter Value Reference/Comments

CAS Name 2-furancarboxaldehyde Furfural Data Sheet+

IUPAC Name 2-furaldehyde or furfural

CAS Number 98-01-1 

Chemical Formula C5H4O2

Chemical Structure 

Chemical Classification Unclassified (it is a heterocyclic aromatic aldehyde)

Pesticide Classification Nematicide, fungicide

SMILES Code O=Cc(occ1)c1 EPI Suite v.4.1 

Molecular Weight 96.085 g/mol HSDB+ 

Color, Odor and Taste Colorless, oily liquid ... Turns yellow to brown on 

exposure to air and light. Almond-like odor, Distinct 

caramel taste 

HSDB+ 

Enthalpy of 

Vaporization 

38.6 KJ/mol(= 9.23 kcal/mol) from HSDB;

42.8 KJ/mol+; 

10.33 Kcal/mol

HSDB; Furfural Physical 

Properties (see below); @ 

http://solvdb.ncms.org/nc

mschph.idc?solvno=0009

8011A 01/21/2015.

Air Diffusion 

Coefficient (cm2

/day) 

0.087 cm2

 s-1 at 25oC, equivalent to 7500 cm2 day-1 Flick, E.W. 1985. 

Industrial Solvents 

Handbook. 3rd ed. Park 

Ridge, NJ: Noyes 
7 

Table 2. Selected Physicochemical Properties for Furfural.

Parameter Value Reference/Comments

Publications, p. 372, cited 

in HSDB 

Water Solubility 

Furfural 

78,100 ppm at 20°C from EPA Fact Sheet

(EPA value selected for modeling.) 

83 g/L = 83,000 ppm at 20°C from HSDB 

74,100 ppm at 25o

C from HSDB 

Highly soluble according to FAO solubility 

classification 

MRID: 47115401, 

46011005/46426501 

HSDB+ & EPA Furfural 

Fact Sheet+ 

FAO 2000 

Vapor pressure 

Furfural 

2.6 torr (mmHg) at 20o

C

Volatility Classification from Dry Non-Adsorbing 

Surfaces: Intermediate to high volatility under field 

conditions, the threshold value for this classification is 

≥3.9×10-5 mmHg (USEPA 2008)

MRID 46011004 

Henry's Law Constant

Furfural 

4.2 x 10-6 atm-m3

/mol

Calculated with s=78,100 ppm & VP=2.6 mmHg, at 

20o

C. 

Experimental solubility 

(S) and vapor pressure 

(VP) are from EPA fact 

sheet

Cwater/Cair (unitless)*

5,717 

Slightly volatile from a water surface (Cwater/Cair is in 

the range 103

 – 105)** 

TFD Guidance 

Air/Water Partition, 

KAW 

* KAW = 1.75x10-4 (log KAW = -3.76)** 

[vs. 

EPISuite v.4.1: KAW = 1.54x10-4 (log KAW = -3.812)] 

**Slightly volatile from a water surface 

The value derived from measured values considered 

representative, as compared to modeled value. 

*Inverse of Cwater/Cair

[EPISuite v.4.1 value 

calculated with log KOW= 

0.41 & HLC=3.77x10-6

atm-m3

/mol] 

Octanol/Water Partition, 

KOW (20o

C) 

KOW = 2.2; log KOW = 0.35 for furfural

vs. log KOW = 0.41 reported in EPISuite v.4.1 

Measured value considered representative.

EPA Furfural Fact Sheet+

EPISuite v.4.1 value 

Octanol/Air Partition, 

KOA

obtained by 3 methods 

* KOA = 1.26x105 = 2.2/ (1.75x10-4); (log KOA = 4.10)

or KOA = 1.26 x105

 = 2.2(8.205746x10-5 m3 atm/Kmol) (293.15K)/ (4.2 x 10-6 atm-m3

/mol); (log KOA = 

4.10) 

[vs. EPISuite value: KOA = 1.67x105

 (log KOA = 

4.222)] 

* KOA = KOW/KAW

* KOA = KOW(RT)/(HLC), 

(Halsall, 2007) 

[EPISuite v.4.1 value] 

Biomagnification 

Potential 

Presumption*: If log KOA > 5, log KOW >2 and the rate 

of chemical transformation is low, the chemical may 

bio-magnify in terrestrial food chains. 

Since for furfural, log KOA=4.1, log KOW=0.35 & rate 

of transformation is high (fast in the environment and 

presumed to be fast in fish), furfural does not have a 

potential to bio-magnify in terrestrial food chains.

*Gobas et al. 2003 and 

Armitage & Gobas, 2007 

support this presumption 

utilized here only as a 

broad reference to 

determine the potential 

for biomagnification. 

Solubility in Organic 

Solvents – Furfural 

Alcohol (infinite)

Ether (infinite) 

Miscible in octanol, acetone, xylene, ethyl acetate, 

methylene chloride and methanol

EPA Furfural Fact Sheet+

Density 1.16 g/mL at 20oC+ EPA Furfural Fact Sheet+

Melting Point/ 

Boiling Point

ca. -37.5o

C 

151.7o

C at 1 atm

MRID 46011004, 

46011005, HSDB+ and 
8 

Table 2. Selected Physicochemical Properties for Furfural.

Parameter Value Reference/Comments

Furfural Physical 

Properties+ 

pKa Does not demonstrate a dissociation constant between 

pKa 2 and pKa 10.

MRID 46011005; 

EPA Furfural Fact Sheet+

Stability of compound at 

room temperature 

Turns to red brown on exposure to air and light and 

resinifies. 

HSDB+

UV/ Vis Absorption 14,591.3 cm3/ mol (at pH 7)+.

Greatest at 297.5-305 nm, measureable through 800 

nm at pH 5 and 7, not measurable at >350 nm at pH 9. 

(Measured between 297.5 and 800 nm in pH 5, 7, and 

9 buffer solutions.) 

Maxima at 228 nm and 277 nm.

EPA Furfural Fact 

Sheet+, MRID 46011005 

and 47115401 

Bolded value considered representative. 

*Calculated by reviewer using the formula Cwater/Cair = [S x T x R x 760 mmHg/Atm] ÷ [P x MW x 106 μg/g], 

where S (solubility) is in μg/mL, T (temperature) is in degrees K, and P (vapor pressure) is in mmHg, R = gas 

constant = 82.08 mL-Atm/K-mol (as cited in TFD Guidance, see below). Calculated with s=78,100 ppm and 

VP=2.6 mmHg, at 20o

C (from MRID 46011004). 

**Burkhard & Guth, 1981; EPA, 1975, classification cited in TFD Guidance at 

http://www.epa.gov/oppefed1/ecorisk_ders/terrestrial_field_dissipation.htm (USEPA 2008, accessed 

01/21/2015); see also USEPA 2010. 

+EPA Furfural Fact Sheet, url: http://www.epa.gov/opp00001/chem_search/reg_actions/registration/fs_PC043301_01-Sep-06.pdf (accessed 01/21/2015):

HSDB, url http://toxnet.nlm.nih.gov/ 01/21/2015; 

Furfural Physical Properties, url: http://www.furan.com/furfural_psychical_properties.html, (accessed 

01/21/2015); 

Furfural data sheet, url: http://www.alanwood.net/pesticides/furfural.html (accessed 01/21/2015). 

Table 3 summarizes environmental fate and transport properties of furfural. For structures of the 

transformation products of furfural and their formation rates in the environmental fate properties, 

refer to Appendix A. 

Table 3. Summary of Environmental Fate Properties for Furfural

Parameter Value Reference/Comments

Hydrolysis t1/2

Parent pH 5, 7, 9 (25o

C) 

Stable at all three pH values. No metabolites were

identified. 

MRID 46011004 (A)

Photolysis t1/2 in water 

Parent (25o

C) 

3.0 – 4.0 days MRID 45426501, 

46011005, 46523601 (A)

Photolysis t1/2 in air 

Parent (27o

C) 

Assuming a troposphere concentration of 1.5x106

 OH/ 

cm3

 (EPISuite v.4.1 assumption), and 12-hour days, the 

half-life for the OH mediated reaction is 0.305 days. 

Bierbach, A., et al. 

(1995) 

Aerobic Soil metabolism 

t1/2

Parent (25o

C for ND SL 

and MSL SL; 20o

C for 

OE SL, DU SL and RM 

SL) 

SL (ND) tR IORE 0.773 hr for furfural and t1/2 SFO = 

1.11 hr for furfural plus furfuryl alcohol (TTRs)

SL (MSL) DT50 1-6 hr (t1/2 assumed 0.25 day) 

SL (DU) DT50 < 1 hr (t1/2 assumed 0.042 day) 

SL (OE) DT50 < 1 day (t1/2 assumed 1 day) 

SL (RM) DT50 < 1 day (t1/2 assumed 1 day) 

SL = sandy loam

MRID 46011007, 

46523701, 46510602, 

47105101 (S) 
9 

Table 3. Summary of Environmental Fate Properties for Furfural

Parameter Value Reference/Comments

Anaerobic Soil 

metabolism t1/2 parent DT50=1-3 days in sandy loam; DT50<3 days for loam, 

loamy sand and sandy clay loam (all four soils from 

ND) (t1/2 assumed 3 days in all cases)

MRID 46426502 (S)

Mobility KOC by HPLC 

(OECD) Method KOC = 6.5 ml/goc; log KOC = 0.815 MRID 47105104 (S)

Laboratory Volatility Volatilization rate during the first 6 hours = 0.114 μg 

furfural/cm2

/hr; Concentration of furfural in the air 

during the first 6 hours = 12.6 μg furfural/m3

 air. 

0.216% of the applied had volatilized after 6 hrs 

(0.244% after 28 days). 

MRID 46106301, 

46523901 (A) 

Field Volatility See Table 4 MRID Nos. 47483901, 

47569101, and 

48252901 (S) 

48704801 – In Review

Terrestrial Field 

Dissipation 

CA and GA, established turf plots, and bareground 

plots, planted to turf: 

t1⁄2’s for furfural range: 0.9-1.5 days1

. 

t1⁄2’s for 2-furoic acid range: 1.1-11.1 days; for furfuryl 

alcohol: 5.8 days1

. 

Maximum residues in top layer: furfural – 14.98% of 

the applied; 2-furoic acid – 93.88% of the applied; 

furfuryl alcohol 14.81% of the applied. 

MRID 47701201 (S)

Bioconcentration in Fish Furfural: KOW = 2.2

2-Furoic acid: KOW=4.4 

Furfuryl alcohol: KOW=1.9 

(KOW <<1000, the potential to bioconcentrate is low).

Waived

A = Acceptable; S = Supplemental 

1 Could calculate only for a subset of the runs because it appeared that the dissipation was fast. 

Furfural exposure in surface and ground water is plausible given its high application rates and 

high mobility (KOC = 6.5 ml/gOC, FAO Mobility Classification, FAO 2000). Furfural may be 

transported to surface waters from runoff events occurring shortly after application to several 

days after application. Furfural can also leach as observed in terrestrial field dissipation studies 

(note that up to 14.98 percent remained in the top layer of the soil, see Table 4). 

Based on limited data, furfural appears to rapidly biodegrade to 2-furoic acid and furfuryl 

alcohol in aerobic and anaerobic soil environments with half-lives ranging from several hours to 

3 days. However, information on the formation of major degradates furfuryl alcohol and 2-

furoic acid only exist from one soil (ND Sandy Loam, MRID No. 47105101). Given the 

available information, these metabolites may be present at very high concentrations due to their 

high formation rates and furfural’s high application rate. Furfural is stable to hydrolysis at 

environmentally relevant pHs. 

Besides runoff to surface water bodies and leaching to ground water, another likely significant 

route of exposure for furfural is volatilization from treated fields. Various field volatility studies 

conducted with surface chemigation applications indicate that furfural may be lost in amounts 

ranging between 4.5 and 88% of the applied. In most of the studies with surface application of 

furfural, there is a strong tendency for the majority of furfural to be released from soil to the 
10 

atmosphere within a couple hours immediately after the application (MRID Nos. 48252901, 

47483901, and 47569101). Both the variations in volatilization flux5 rates with surface furfural 

applications and the immediate volatilization after application are likely due to the watering-in 

practice mobilizing furfural from soil to air6

 For shank injected applications of furfural to bare 

soil plots (use not yet registered), it appears that releases to the atmosphere are very small, but 

still discernible (MRID No. 48708401). Table 4 summarizes the results from various field 

volatility studies for furfural. 

Table 4. Summary of furfural field volatility studies and volatile flux measurements.

Field Volatility Study 

(Application Rate) 

Time 

Applied MRID Study Classification 

Peak Mass 

Loss 1

(of 

applied) 

Cumulative 

Mass Loss 

(% of applied) 

Ft. Pierce, FL 

Field 12

 - 

Sprinkler Chemigation to Turf 

Plot, watered-in 

(58.8 lbs. a.i./A) 

March 1, 

2010 

9:21 am 

48252901 Supplemental 87.55 87.69 percent 

through 

69 hours postapplication 

Ft. Pierce, FL 

Field 23 - 

Shank Injection and Roto-tillage 

to Untarped Bare Soil Plot, 

watered-in 

(396.4 lbs. a.i./A) 

March 14, 

2011 

7:58 am 

48708401 In Review < 1 < 1 percent 

through 142 

hours postapplication 

Porterville, CA 

App. 23

 – 

Sprinkler Chemigation to Turf 

Plot, watered-in 

(139 lbs. a.i./A) 

February 6, 

2008 

8:17 am 

47483901 Supplemental 49.20 55.4 percent 

through 

48 hours postapplication 

Montezuma, GA 

App. 33

 – 

Sprinkler Chemigation to Turf 

Plot, watered-in 

(139 lbs. a.i./A) 

April 20, 

2008 

2:30 pm 

47569101 Supplemental 4.42 % 4.42 % mass 

loss through 

48 hours postapplication 

1. Peak mass loss refers to the average over 1 - 2 hours as per the sampling periods in the field volatility studies. 

2. Field 1 most pertinent since furfural application to field 2 plot was not watered in following label requirements, 

and a malfunction occurred on field 3. 3. The Ft. Pierce, FL Field 2 shank injection application to untarped bare soil plot, Porterville, CA Application 2 to 

turf plot. and Montezuma, GA Application 3 to turf plot sites possessed the highest measured flux rates. 

 

5

 Flux is the term used to describe how much volatilization of a pesticide can occur across a given area for specific 

period of time. 

6

 While watering-in practices is expected to also force furfural downward below the root zone, watering in practices 

with furfural surface sprays can result in the randomized motion of furfural molecules into the atmosphere at the 

same time as well. 
11 

Furfural biodegrades mainly to 2-furoic acid and furfuryl alcohol in aerobic and anaerobic 

environments; these metabolites may be present at high concentrations in the soil due to the high 

applications rates for furfural. Both 2-furoic acid and furfuryl alcohol have similar solubility and 

vapor pressure physical-chemical properties to furfural. As such, both degradates have some 

potential to leach given solubility values greater than 10,000 mg/L. Furthermore, the vapor 

pressures for both degradates are in the range of furfural’s vapor pressure with values between 

0.033 – 0.609 torr. . Further information about furfural’s metabolites is provided in Appendix 

A. 

In anaerobic environments, additional ring-opened metabolites propionic acid and acetic acid are 

also observed. Furthermore, upon aqueous photolysis, ring-opened metabolites include succinic 

acid, malonic acid, 2-ketoglutaric acid, propionic acid and formic acid. Some of these ringopened products are part of the biological Kreb’s cycle (e.g. 2-ketoglutaric acid and succinic 

acid), and it appears that all of the identified compounds are simple acids that may be present in 

natural soil environments. Therefore, in future assessments, these degradates will not considered 

stressors since they are not expected to possess higher toxicity than the furfural, furfuryl alcohol, 

and 2-furoic acid. Please refer to Section 8 on the residues of concern that will be evaluated in 

the risk assessment. 

The physicochemical characteristics of furfural’s metabolites, 2-furoic acid and furfuryl alcohol, 

are presented in Table 5. 

Table 5. Selected Physicochemical Properties for 2-Furoic Acid and Furfuryl Alcohol, Major 

Metabolites of Furfural

Parameter Value Reference/Comments

CAS Number 2-Furoic acid 88-14-2 Furfuryl alcohol 98-00-0 EPI Suite v.4.1 

Chemical Formula/ 

Molecular Weight

C5H4O3 / 112.09 g/mol C5H6O2 / 98.10 g/mol EPI Suite v.4.1 

Chemical Structures 

2-furoic acid Furfuryl alcohol

SMILES Code O=C(O)c(occ1)c1 C1=C(CO)OC=C1 EPI Suite v.4.1 

pKa for 2-furoic acid 3.6 Bansal 1999 

Vapor pressure 

Metabolites 

2-Furoic acid – 0.033 torr at 25oC or 0.103 torr#

Furfuryl alcohol – 0.609 torr at 25oC## 

For both chemicals, volatility classification from dry 

non-adsorbing surfaces is “intermediate to high 

volatility under field conditions”

# and ## See footnotes 

below. 

USEPA 2008 

Octanol/Water Partition, 

KOW (20o

C) for 

Metabolites 

2-furoic acid exp.

log KOW=0.64; KOW=4.4 

Furfuryl alcohol exp.

log KOW=0.28; KOW=1.9 

Pomona, 1987; Hansh, C. 

et al. 1995 (referenced in 

EPISuite v.4.1) 

Water Solubility for

Metabolites 

2-furoic acid: 37,100 mg/L at 15oC

Furfuryl alcohol: 1x106

 mg/L, miscible at 15oC 

Both chemicals are highly soluble according to FAO 

solubility classification (FAO 2000) 

Yalkowsky, S.H. & R.M. 

Dannenfelser, 1992; 

McKillip, W.J. & E. 

Sherman, 1978 (both 

from EPISuite v.4.1)
12 

Table 5. Selected Physicochemical Properties for 2-Furoic Acid and Furfuryl Alcohol, Major 

Metabolites of Furfural

Parameter Value Reference/Comments

Henry's Law Constant

Metabolites 

2-furoic acid: 

4.1 x 10-7 atm m3

/mol 

Furfuryl alcohol: 

negligible (as it is 

miscible with water)

Estimated using solubility 

and vapor pressure 

#Vapor pressure for 2-furoic acid from: http://www.thegoodscentscompany.com/data/rw1040161.html

(accessed 01/23/2015). 

##Vapor pressure for furfuryl alcohol from Daubert, T.E. & R.P. Danner. Physical and Thermodynamic 

Properties of Pure Chemicals Data Compilation. Washington, D.C.; Taylor and Francis, 1989 as cited in 

TOXNET Database, and EPISuite v.4.1, respectively.
13 

6. Receptors 

a. Effects to Aquatic Organisms 

Table 6 provides a summary of the aquatic taxonomic groups and surrogate species tested to 

characterize the potential acute and chronic ecological effects of furfural. In addition, the tables 

provide a preliminary overview of the potential acute toxicity of Furfural by providing the acute 

toxicity classifications. Based on the available ecotoxicity information furfural is classified as 

moderately toxic to freshwater fish (lowest LC50 = 3.06 ppb), marine/estuarine organisms (lowest 

LC50 = 14 ppm), and birds (lowest LD50 = 85 mg/kg). It is classified as slightly toxic to 

freshwater and estuarine/marine invertebrates (LC/EC50 = 20.4 ppm; LC/EC50 = 15 ppm) and 

practically non-toxic to honeybees (LD50 > 100 ug/bee). As with acute toxicity, fish (NOAEC = 

0.038 ppm) also appear to be more sensitive to chronic exposure than aquatic invertebrates 

(NOAEC = 0.12 ppm). The most sensitive aquatic plant based on NOAEC is duckweed (0.49 

ppm), while the algae S. costatum (most sensitive based on LC50) has a NOAEC of 13 ppm. 

Table 6. Summary of the Endpoints from Aquatic Toxicity Studies for 

Furfural.

Exposure 

Scenario Species Exposure Duration

Toxicity 

Reference 

Value 

(ppm a.i.) 

Reference 

Freshwater Fish 

Acute Rainbow trout 96 hours 

LC50 = 3.06 ppm MRID 

46343002 

(moderately toxic) Supplemental 

Acute Fathead 

minnow 96 hours 

LC50 = 28 ppm 448873301 

Slightly toxic Acceptable 

Acute Bluegill sunfish 96 hours 

LC50 = 5.8 ppm MRID 

46207301 

(moderately toxic) Acceptable 

Chronic Fathead 

minnow 32 days NOAEC = 0.038 

ppm 

MRID 

47692201 

Supplemental 

Freshwater Invertebrates 

Acute Daphnia magna 48 hours 

LC50 /EC50 = 20.4 

ppm 

(slightly toxic) 

MRID 

46343001 

Acceptable 
14 

Table 6. Summary of the Endpoints from Aquatic Toxicity Studies for 

Furfural.

Exposure 

Scenario Species Exposure Duration

Toxicity 

Reference 

Value 

(ppm a.i.) 

Reference 

Chronic Daphnia magna 21 days NOAEC = 1.9 

ppm 

MRID 

47035301 

Acceptable 

Estuarine/Marine Fish 

Acute Sheepshead 

minnow 96 hours 

LC50 = 14 ppm MRID 

46426509 

 (slightly toxic) Acceptable 

   

Chronic Sheepshead 

minnow 

29-d Early 

Life Stage 

NOAEC = 0.33 

ppm; LOAEC = 

1.0 ppm 

49048802 

Acceptable 

Estuarine/Marine Invertebrates 

 Acute Mysid shrimp 48 hours 

LC50 = 15 ppm MRID 

46426508 

 (slightly toxic) Supplemental 

   

 Acute Oyster shell 

deposition 96 hours 

EC50 = 18 ppm MRID 

46426507 

 (slightly toxic) Acceptable 

Chronic Mysid shrimp 28-d Life 

Cycle 

NOAEC = 0.12 

pmm; 

LOAEC=0.29 

ppm 

49048801 

Acceptable 

Aquatic Plants 

Acute Lemna 7 days 

EC50 = 30 ppm MRID 

47569401 

NOAEC = 0.49 

ppm Supplemental 

Acute S. costatum 96 hours 

EC50 = 23 ppm MRID 

47569403 

NOAEC = 13 

ppm Supplemental 

Acute P. subcapitata 96 hours 

EC50 = 43 ppm MRID 

47569402 

NOAEC = 16.5 

ppm 

Supplemental 
15 

Table 6. Summary of the Endpoints from Aquatic Toxicity Studies for 

Furfural.

Exposure 

Scenario Species Exposure Duration

Toxicity 

Reference 

Value 

(ppm a.i.) 

Reference 

Acute N. pelliculosa 96 hours 

EC50 = 31 ppm MRID 

47569404 

NOAEC = 5.8 

ppm Supplemental 

Acute A. flos-aquae 96 hours 

EC50 = 61 ppm MRID 

47569405 

NOAEC = 12 

ppm Supplemental 

1 Freshwater fish may be surrogates for aquatic-phase amphibians. 

b. Effects to Terrestrial Organisms 

Table 7 provides a summary of terrestrial taxonomic groups and surrogate species tested to 

characterize the potential acute and chronic ecological effects of furfural. The acute oral LD50 in 

rats is 107 mg/kg and the developmental NOAEL in rats (oral gavage) is 10 mg/kg/day. The 

acute mammal inhalation LC50 in rats is 0.54 – 1.63 mg/L, while the avian acute inhalation 

determined an LC50 of 278.5 mg/kg. The rat subchronic inhalation toxicity NOAEL is 

equivalent to 0.007 mg/l. The dietary toxicity of birds and determined the NOAEC at 4930 

mg/kg diet, the highest concentration tested. A terrestrial plant seedling emergence study shows 

the monocot NOAEC = 398 lb ai/A (all species tested) and most sensitive dicot NOAEC = 29 lb 

ai/A (lettuce). A terrestrial plant vegetative vigor study shows the most sensitive monocot 

NOAEC = 69.4 lb ai/A (corn) and most sensitive dicot NOAEC = 16.9 lb ai/A (sugarbeet). 

Uncertainty remains as to the toxicity of furfural in the vapor phase to terrestrial invertebrates 

(determined with the honeybee) and terrestrial plants, as well as acute oral toxicity of furfural to 

passerine species and the dietary toxicity of furfural to a water fowl species. The requirement of 

of the passerine species has been waived due to difficulty with conducting studies with passerine 

species (DP Barcode D410714). The waiver response stated that an acute oral or sub-acute 

dietary study would not greatly impact the overall risk picture given that inhalation has been 

identified as the primary route of exposure. Additionally, the avian reproduction data 

requirement has been waived due to the volatility of furfural would result in unrealistic exposure 

to birds.(DP Barcode D399351; Table 10). 

Table 7. Summary of the Endpoints from Terrestrial Toxicity Studies for furfural. 

Exposure 

Scenario Species Exposure Duration 

Toxicity 

Reference 

Value1 Reference 

Mammals (see table below from HED for additional studies) 
16 

Table 7. Summary of the Endpoints from Terrestrial Toxicity Studies for furfural. 

Exposure 

Scenario Species Exposure Duration 

Toxicity 

Reference 

Value1 Reference 

Acute oral Rat Single oral dose 

LD50 = 107 

mg/kg 

MRID 

46011009 

Acceptable 

(moderately 

toxic) 

Acute 

inhalation Rat 4-hour inhalation 

LC50 = 0.54 – 

1.63 mg/L 

MRID 

46106302 

Acceptable 

Developmental 

Rat Gestation day 6 through 15 

NOAEL = 10 

mg/kg/day 

MRID 

46147601 

(Reproduction 

study not avail.) 

(based on 

maternal 

effects at 

higher levels 

that could 

affect 

reproduction) 

Acceptable/ 

guideline 

     

Birds 

Acute 

Northern 

bobwhite quail 14 days 

LD50 = 85 

mg/kg 

MRID 

47035302 

(moderately 

toxic) Acceptable 

Acute Mallard 14 days 

LD50 = 360.5 

mg/kg 

MRID 

46343004 

(moderately 

toxic) Acceptable 

Acute Japanese quail 14 days 

LD50 = 278.5 

mg/kg 

MRID 

4634003 

(moderately 

toxic) Supplemental 

Acute 

Inhalation 

Northern 

bobwhite quail 4 hrs 

LD50 = 253 

ppm 

(moderately 

toxic) 

MRID 

48120801 

Acceptable 

Dietary 

Northern 

bobwhite quail 8 days 

LD50 > 

4930mg/kg 

diet; NOAEC = 

4930 mg/kg 

diet 

MRID 

48120802 

Acceptable 

Reproduction Bobwhite/Mallard NA NA 

Waived (DP 

Barcode 

D399351) 
17 

Table 7. Summary of the Endpoints from Terrestrial Toxicity Studies for furfural. 

Exposure 

Scenario Species Exposure Duration 

Toxicity 

Reference 

Value1 Reference 

Terrestrial Plants 

Seedling 

emergence 

10 species (4 

monocot, 6 

dicot) 

21 days 

Monocot 

 EC25 = >398 lb 

ai/A 

NOAEL = 398 

lb ai/A 

 

Dicot 

EC25 = 87 lb 

ai/A 

NOAEL = 29 

lb ai/A 

MRID 

47701204 

Acceptable 

Vegetative 

vigor 

10 species(4 

monocot, 6 

dicot) 

21 days 

Monocot 

MRID 

47720301 

Acceptable 

 EC25 = 130 lb 

ai/A 

NOAEL = 69.4 

lb ai/A 

 

Dicot 

EC25 = 240 lb 

ai/A 

NOAEL = 16.9 

lb ai/A 

Terrestrial Invertebrates 

Honeybee 

acute contact Honeybee 48 hours 

LD50 > 100 

ug/bee 

MRID 

47300201 

(practically 

nontoxic) Acceptable 

   

Honeybee 

acute oral 

Honeybee 96 hours 

LD50 > 100 

ug/bee 

MRID 

46331505 

 (not OCSPP 

guideline) Supplemental 

   

Earthworm 

(not OCSPP 

guideline) Earthworm 14 days 

LC50 = 406.18 

mg/kg 

MRID 

46331506 

Supplemental 

 1 Mammal data from 7/27/06 HED Furfural Assessment (and EFED statistical analysis of acute oral data provided by 

RD/TRB). 1 Birds represent surrogates for terrestrial-phase amphibians and reptiles. 
18 

c. Ecological Incidents 

The ecological incident information system (EIIS) is an OPP database that houses ecological 

incidents that have been reported to the Agency. When available, EIIS includes date and 

location of an incident, type and magnitude of effects observed in various species, use(s) of 

pesticides known or suspected of contributing to the incident, and results of any chemical residue 

analysis or other analyses conducted during incident investigation. EIIS incidents are 

categorized according to the certainty that the incident resulted from pesticide exposure. The 

Avian Monitoring System (AIMS) is a database administered by the American Bird Conservancy 

that contains publicly available data on reported avian incidents involving pesticides. Many of 

the incidents listed in this database are also in the EIIS. 

As of January 26, 2015, EIIS did not return any ecological incidents involving Furfural. 

As of January 26, 2015, AIMS did not identify any ecological incidents involving Furfural. 

7. Exposure Pathways of Concern 

Given furfural’s volatile and soluble physical chemical properties, broad spectrum mode of 

action as a fumigant, and application to soil, turf, and ornamentals up to six times per year, the 

following lists the pathways of exposure anticipated for furfural applications: 

 Inhalation exposure for mammals, birds, and terrestrial invertebrates (honey bee) 

(acute) 

 Air exposure for plant vegetation

Furfural has been shown to escape to the atmosphere from soil in large quantities over short time 

frames close to the time of application from the collection of field volatility studies submitted to 

the Agency. Despite previous risk assessments not showing risk due to furfural exposure, 

existing and more recent field volatility studies will be utilized to evaluate furfural air exposure 

to mammals, birds, plants, and terrestrial invertebrates according to all registered uses of furfural 

at the time of the Preliminary Registration Review Risk assessment. Since furfural sprays are 

anticipated to volatilize rapidly, spray drift is not expected to be of concern for terrestrial 

organisms. 

 Soil exposure for plant seedlings

Furfural exposure to plant seedlings off the treated field is expected from furfural applications. 

Furfural’s mode of action, its large application rates to soil, and the mobile and highly soluble 

characteristics of furfural in water all justify this exposure pathway. 

 Aquatic exposure for freshwater fish, estuarine marine organisms, aquatic 

invertebrates, and aquatic plants (acute and chronic) 

Furfural aquatic exposure can occur if rain events occur close to the time of applications. When 

rain events occur, large amounts of furfural that are present on the field can dissolve and runoff 
19 

to neighboring water bodies. Runoff of furfural may occur particularly given the situations with 

untarped applications. Spray drift exposure is not expected since furfural sprays are anticipated 

to volatilize shortly after application. 

 Drinking water exposure for mammals and birds

While dietary and drinking water exposures are possible for mammals and birds, acute risk from 

inhalation is determined to be primary route of exposure for several reasons. For birds, based on 

furfural’s vapor pressure and calculations using STIR, the maximum 1-hour vapor inhalation 

dose for birds is 16,900 mg/kg. By contrast, based on furfural’s solubility limit and calculations 

using SIP, the upper bound daily drinking water intake dose for a bird is 63,261 mg/kg bw. 

Multiplying the STIR estimate of one hour by 24 (to match the daily exposure duration of the 

SIP estimate) yields 405,600 mg/kg which is approximately one order of magnitude more than 

the SIP drinking water dose. For mammals, the drinking water exposure dose estimated by SIP 

is even lower indicating an even wider margin of increased exposure potential due to inhalation. 

For furfural, this suggests that the potential daily inhalation exposure for bothbirds and 

mamamals are substantially greater than the potential daily drinking water exposure indicating 

that inhalation exposure may be of more concern. The comparisons of the drinking water 

exposure dose and inhalation exposure dose for furfural described here can be verified in the SIP 

and STIR evaluations shown in Appendix C. 

Therefore, while the potential for drinking water exposure exists to birds and mammals, 

inhalation exposure is determined to be the one of primary concern for the terrestrial risk 

assessment. By being protective of birds and mammals via the inhalation route of exposure, 

EFED believes that the dietary and drinking water routes of exposure will be protected as well. 

 Dietary exposure for mammals and birds

Direct dietary exposure to non-target terrestrial organisms (birds and mammals) is possible due 

to the direct deposition of furfural sprays on turf grass and ornamentals, enabling the 

bioavailability of furfural. However, minimal impacts are anticipated for piscivorous birds and 

mammals since bioaccumulation of residues are anticipated to be low in fish given furfural’s Log 

Kow value of 0.35 – 0.41 (EPA Furfural Fact Sheet; EPISuite WSKOW v.1.41). The risk 

assessment will cover risks appropriate to registered uses of furfural at the time that the 

preliminary registration review risk assessment is completed. 

8. Analysis Plan 

a. Stressors of Concern 

Furfuryl alcohol and 2-furoic acid are among the major degradates that are observed to form in a 

furfural aerobic soil metabolism laboratory study with ND Sandy Loam soil (MRID No. 

47105101). Please refer to Section 5 and Appendix A for an additional discussion and 

information related to the formation furfuryl alcohol and 2-furoic acid. 
20 

Stressors of concern evaluated in this risk assessment will include furfural and furfuryl alcohol. 

Both furfural and furfuryl alcohol have been identified as the stressors of concern for ecological 

and human health in consultation with the Residues of Concern Knowledgebase Subcommittee 

(ROCKS, meeting dated December 15, 2009). 

The relative toxicity of the other major degradate 2-furoic acid in soil and water as compared to 

parent furfural were examined using ECOSAR. ECOSAR results of the toxicity of 2-furoic acid 

compared to the parent furfural indicate that this degradate is 2 -3 orders of magnitude less toxic 

than parent furfural depending on the exposure duration and taxa of concern. This analysis is 

included in Appendix B. 

Additional ring-opened metabolites propionic acid and acetic acid are also observed in anaerobic 

soil environments. Furthermore, with aqueous photolysis, ring-opened metabolites include 

succinic acid, malonic acid, 2-ketoglutaric acid, propionic acid and formic acid. Some of these 

ring-opened products are part of the biological Kreb’s cycle (e.g. 2-ketoglutaric acid and succinic 

acid), and it appears that all of the identified compounds are simple acids that may be present in 

natural soil environments. Therefore, in future assessments, these degradates will not be 

considered stressors since they are not expected to possess higher toxicity than the furfural and 

furfuryl alcohol. 

In the absence of toxicity data, furfuryl alcohol is assumed to have similar toxicity to furfural. 

Therefore, furfuryl alcohol and furfural will be assessed together using a Total Residue (TR) 

approach for the total toxic residues (TTRs). This modeling strategy requires an assumption that 

all residues of concern have similar physical, chemical, and partitioning characteristics. 

Application rates for the parent pesticide are used to represent the total mass loading of pesticide 

and its degradation product. This modeling approach does not consider temporal occurrence of 

degradation products. 

b. Measures of Exposure 

Aquatic Modeling 

EFED will use the Surface Water Concentration Calculator as the standard available model to 

evaluate potential exposures to aquatic organisms. The SWCC is described at the following 

website: http://www.epa.gov/pesticides/science/models_pg.htm#aquatic (accessed 01/28/2015). 

Terrestrial Modeling 

 Dietary Exposure 

EFED will use the T-REX model to evaluate exposure on food items containing furfural residues 

applied to turf grass and ornamentals. The T-REX model is available at the following website: 

http://www.epa.gov/oppefed1/models/terrestrial/index.htm#trex (accessed 01/28/2015). 

 Terrestrial Plant Seedlings 
21 

For exposure to plant seedlings, TerrPlant (ver 1.2.2) will be used. TerrPlant EECs are based on 

runoff, and therefore will capture the overall exposure of plant seedlings resulting from runoff of 

dissolved furfural off-site from the treated field. The TerrPlant model is available at the 

following website: http://www.epa.gov/oppefed1/models/terrestrial/index.htm#terrplant. The 

Agency is currently developing a replacement model for TerrPlant. If the replacement has been 

approved prior to the initiation of the risk assessment, this new model will be used instead. 

 Air Exposure and Inhalation for Mammals, Birds, and Vegetation 

Furfural acute exposures of birds and mammals through inhalation as well as terrestrial 

invertebrates and plants via gas-phase exposure are determined using the estimated exposure 

concentrations (EECs) from atmospheric dispersion models. These models rely on the input of 

furfural atmospheric flux measurements from the collection of volatility (flux) studies that are 

available associated with furfural applications in the field. The Agency’s recommended 

screening near-field dispersion model, the American Meteorological Society/EPA Regulatory 

Screening Model (AERSCREEN v. 11060), will be used to generate Tier I EECs. The Tier I 

analysis will consider the maximum application rate, maximum flux rate for each application 

method from the collection of furfural flux studies, and worst-case meteorological conditions 

(light winds and stagnant conditions) to calculate peak air EECs. Peak one-hour average 

concentrations will be the basis of EECs. Documentation on the AERSCREEN model is 

available at http://www.epa.gov/scram001/dispersion_screening.htm (accessed 1/28/2015). The 

exposure scenario evaluated in the Tier 1 analysis will assume that the terrestrial receptors are 

directly downwind from the emissions source. This is illustrated in Figure 1 below. 

Figure 1. Schematic showing air exposure scenario due to volatilization and subsequent 

release from soil evaluated in Tier 1 analysis. 

If the Tier 1 EECs for furfural applications result in an exceedance of the LOC for mammals, 

birds, or plants, EECs will be further examined using the Tier 2 model, the Probabilistic 

Exposure and Risk Model for Fumigants (PERFUM v. 2.5.1). PERFUM is parameterized by 

time series of flux data obtained from field volatility studies. PERFUM considers these flux 

Wind, Dispersion, 

and 

Accumulation 

of Vapors or Gas

Volatilization of 

residues in soil

Furfural spray 

chemigation 

application 
22 

values with a robust statistical sampling of meteorological data from points within rings 

surrounding a treated field (usually 5 years of hourly meteorological data). The current version 

of PERFUM processes estimated air concentrations from EPA’s previously recommended 

atmospheric dispersion model in the near field, the Industrial Source Complex Short-Range 

Model, Version 3 (ISCST3). ISCST3 has since been replaced by the refined mode of 

AERSCREEN, the AERMOD model, as the recommended refined dispersion model in the near 

field. However, both ISCST3 and AERMOD are similar in that they both use Gaussian plume 

dispersion principles. The framework for PERFUM is illustrated in Figure 2 below. Estimated 

air concentrations are calculated and binned by percentile distributions within each ring and 

averaging time period. First, a peak one-hour averaging period will be used to calculate air 

EECs. If necessary, a higher averaging period equivalent to the exposure duration in toxicity 

studies will be used to characterize the RQs resulting from utilizing the one-hour peak EECs. 

The highest 90th percentile estimated air concentration from all averaging periods from the 

receptor ring closest to the edge of the field will be considered as the upper-bound EEC to 

determine the RQ. The PERFUM model is publically available on the web from the following 

link: 

http://www.exponent.com/projectdetail.aspx?project=450 (accessed 1/28/2015). For this 

assessment, maximum air exposure will occur at the edge of the field corresponding to where 

furfural mass emissions from the treated field will accumulate to maximum levels along the fetch 

of wind blowing over the treated field. 

Figure 2. Illustration of the spatial and temporal aspects of the source to receptor 

configuration in PERFUM. The wind rose (left) illustrates the frequency distribution of 

variations in wind speed and wind direction that PERFUM accounts for in the transport of 

the vapor plume from the treated source to receptors (right).

All modeling scenarios will be parameterized based on field volatility flux data normalized to the 

maximum field sizes specified by application method on the labels. Therefore, the modeling will 

be based on a maximum field size of 40 acres for all applications as specified on the label. 

Available Monitoring Data 

Treated 

Field 

Receptor 

Rings 
23 

The Agency is not aware of monitoring conducted by federal and state agencies and this route of 

exposure will be considered in the assessment to the extent that data on furfural becomes 

available. 

c. Measures of Effect 

Toxicity data presented in Section 3 of this problem formulation will be used to calculate risk 

quotients. Any additional information submitted by the registrant or found in the open literature 

prior to conduct of the risk assessment will also be considered. The open literature studies are 

identified using EPA’s ECOTOXicology database (ECOTOX) (USEPA, 2007), which employs a 

literature search engine for locating chemical toxicity data for aquatic life, terrestrial plants, and 

wildlife. The evaluation of both sources of data can also provide insight into the direct and 

indirect effects of pesticides on biotic communities from loss of species that are sensitive to the 

chemicals and from changes in structure and functional characteristics of the affected 

communities. 

9. Endangered Species Assessments 

Consistent with EPA’s responsibility under the Endangered Species Act (ESA), the Agency will 

evaluate risks to federally listed threatened and endangered (listed) species from registered uses 

of pesticides in accordance with the Joint Interim Approaches developed to implement the 

recommendations of the April 2013 National Academy of Sciences (NAS) report, Assessing 

Risks to Endangered and Threatened Species from Pesticides. The NAS report outlines 

recommendations on specific scientific and technical issues related to the development of 

pesticide risk assessments that EPA and the Services must conduct in connection with their 

obligations under the ESA and FIFRA. EPA will address concerns specific to furfural in 

connection with the development of its final registration review decision for furfural. 

In November 2013, EPA, the U.S. Fish and Wildlife Service, National Marine Fisheries (the 

Services), and USDA released a white paper containing a summary of their joint Interim 

Approaches for assessing risks to listed species from pesticides. These Interim Approaches were 

developed jointly by the agencies in response to the NAS recommendations, and reflect a 

common approach to risk assessment shared by the agencies as a way of addressing scientific 

differences between the EPA and the Services. Details of the joint Interim Approaches are 

contained in the November 1, 2013 white paper, Interim Approaches for National-Level 

Pesticide Endangered Species Act Assessments Based on the Recommendations of the National 

Academy of Sciences April 2013 Report.

Given that the agencies are continuing to develop and work toward implementation of the 

Interim Approaches to assess the potential risks of pesticides to listed species and their 

designated critical habitat, this ecological problem formulation supporting the Preliminary Work 

Plan for furfural does not describe the specific ESA analysis, including effects determinations for 

specific listed species or designated critical habitat, to be conducted during registration 

review. While the agencies continue to develop a common method for ESA analysis, the 

planned risk assessment for the registration review of furfural will describe the level of ESA 
24 

analysis completed for this particular registration review case. This assessment will allow EPA to 

focus its future evaluations on the types of species where the potential for effects exists, once the 

scientific methods being developed by the agencies have been fully vetted. Once the agencies 

have fully developed and implemented the scientific methods necessary to complete risk 

assessments for listed species and their designated critical habitats, these methods will be applied 

to subsequent analyses of furfural as part of completing this registration review.

 

10. Endocrine Disruptor Screening Program 

Furfural was not included in the first group of 67 chemicals issued an order to conduct Tier 1 

EDSP testing, nor was it included in the second group of 109 chemicals identified for EDSP 

testing. For additional information the EDSP program, visit http://www.epa.gov/endo/. 

11. Drinking Water Assessments 

Section 4b describes the current status of drinking water assessments that have been conducted 

for the existing uses of furfural. A formal drinking water assessment will be finalized covering 

all of furfural uses at the time of the Preliminary Registration Review Risk Assessment is 

conducted. The drinking water assessment will address the issues previously identified with 

drinking water exposure in both surface water and ground water sources. Surface water 

exposure will be evaluated using the Surface Water Concentration Calculator (SWCC). The 

SWCC is available at the following website: 

http://www.epa.gov/pesticides/science/models_pg.htm#aquatic (accessed 01/28/2015). 

Ground water exposure will be evaluated using the Pesticide Root Zone Model in Ground Water 

(PRZM-GW) model. The PRZM-GW model is available at the following website: 

http://www.epa.gov/oppefed1/models/water/index.htm#przm_gw (accessed 01/28/2015). 

12. Preliminary Identification of Data Gaps 

a. Environmental Fate

Tables 8 and 9 identify environmental fate studies by MRID that offer data for each guideline 

requirement, as well as study classifications and whether or not further data are needed in order 

to support risk assessment. 

Table 8. Submitted Environmental Fate Data for Furfural

OCSPP 

Guideline 

Data 

Requirement 

Submitted 

Studies 

(MRID) 

Study 

Classifications

Are data 

needed to 

conduct risk 

assessment?

Justification and Assumptions EPA 

will Make in Absence of Data 

835.2120 Hydrolysis 46011004 Acceptable No --- 
25 

Table 8. Submitted Environmental Fate Data for Furfural

OCSPP 

Guideline 

Data 

Requirement 

Submitted 

Studies 

(MRID) 

Study 

Classifications

Are data 

needed to 

conduct risk 

assessment?

Justification and Assumptions EPA 

will Make in Absence of Data 

835.2240 Aqueous 

photolysis 

46011005, 

46426501, 

46523601 

Acceptable No --- 

835.2410 Soil photolysis Not available Waived No According to the method of application, 

furfural is watered into the soil; 

therefore, soil photolysis is unlikely. 

835.2370 Air photolysis Bierbach, et al.

1995 

Screened No Study provides information about the 

rate of OH radical reaction for furfural. 

This study was screened. 

835.4100 Aerobic soil 

metabolism 

46011007, 

46510602, 

46523701, 

47105101, 

49583601 

Supplemental 

In Review1

Yes Study was required as part of the 

conditional registration of furfural. The 

available studies do not provide suitable 

information or there is uncertainty with 

respect to the transformation products 

furfuryl alcohol and 2-furoic acid. In 

order to address this uncertainty, the 

study should closely monitor the 

transformation products in addition to 

the parent compound, and avoid 

problems observed in the previous 

studies. The data will be used in reestimating the input parameters to be 

used in the aquatic models. Three 

aerobic soils are required. In the 

absence of the additional data, EFED 

may make conservative assumptions 

about the persistence of furfural and its 

degradate of concern in soil systems. 

835.4200 Anaerobic soil 

metabolism 

46426502, 

46966001, 

46966002 

Supplemental Yes Study was required as part of the 

conditional registration of furfural. The 

available study does not provide suitable 

information or there is uncertainty with 

respect to the transformation products 

furfuryl alcohol and 2-furoic acid. In 

order to address this uncertainty, the 

study should closely monitor the 

transformation products in addition to 

the parent compound, and avoid 

problems observed in the previous 

study. Four anaerobic soils are 

required. In the absence of the 

additional data, EFED may make 

conservative assumptions about the 

persistence of furfural and its degradate 

of concern in soil systems. 
26 

Table 8. Submitted Environmental Fate Data for Furfural

OCSPP 

Guideline 

Data 

Requirement 

Submitted 

Studies 

(MRID) 

Study 

Classifications

Are data 

needed to 

conduct risk 

assessment?

Justification and Assumptions EPA 

will Make in Absence of Data 

835.4300 Aerobic aquatic 

metabolism 

Not available Not applicable Yes There is lack of knowledge about the 

fate and persistence of furfural and its 

transformation products in aquatic 

systems. This knowledge is needed for 

an appropriate aquatic modeling using 

the SWCC model. An aerobic aquatic 

metabolism study is being 

recommended for this fumigant-like 

chemical. In the absence of the 

additional data, EFED may make 

conservative assumptions about the 

persistence of furfural and its degradates 

in aquatic systems. 

835.4400 Anaerobic 

aquatic 

metabolism 

Not available Not applicable No --- 

835.1230 

835.1240 

Adsorption/ 

desorption and 

leaching 

46011006, 

46523801, 

47105104, 

47115401 

Supplemental No --- 

835.1410 Volatility – 

laboratory 

46106301, 

46523901 

Acceptable No --- 

835.6100 Terrestrial field 

dissipation 

477012012 Supplemental No --- 

835.8100 Field Volatility 47483901, 

47569101, 

48252901 

Supplemental No --- 

48704801 In Review 

850.1730 Fish 

bioconcentration 

Not available Waived No Furfural, 2-furoic acid and furfuryl 

alcohol’s 1-octanol/ water partition 

coefficients are very low (KOW=2.2, 4.4 

and 1.9, respectively), indicating a very 

low tendency to bioaccumulate/ 

bioconcentrate in fish tissues 

(D346394+). 

850.6100 Analytical 

method in soil 

49583501 

49478104 

In Review No ECM: 49583501 

ILV: 49478104 

Analytical 

method in water 

49478102, 

49478101, 

49478103, 

46207301 

(Appendix 4)

In Review No ECM: 46207301 (Appendix 4) and 

49478102 

ILV: 49478101 and 49478103 

Analytical 

method in air 

49478105 In Review No ECM & ILV: 49478105 
27 

Table 8. Submitted Environmental Fate Data for Furfural

OCSPP 

Guideline 

Data 

Requirement 

Submitted 

Studies 

(MRID) 

Study 

Classifications

Are data 

needed to 

conduct risk 

assessment?

Justification and Assumptions EPA 

will Make in Absence of Data 

Nonguideline Subsurface 

degradation 

Not available Not applicable Yes A study to investigate the fate of furfural 

in subsurfaces is needed in order to 

refine the Estimated Drinking Waters 

Concentrations (EDWCs). Current 

PRZM-GW modeling allows to enter the 

aerobic soil metabolism and hydrolysis 

as input parameters. Since under 

hydrolysis conditions the chemical is 

stable, the model assumes no 

degradation below the top 1 meter level. 

The subsurface study will help in 

refinement of the groundwater EDWCs. 1 This study may be used to fulfill the data request, but determination of this is pending since it is still under review. 

Therefore, the request for the aerobic soil metabolism study still exists at this time. 2 Multiple additional MRIDs are associated with this terrestrial field dissipation study.

Table 9. Submitted Environmental Fate Data for the Furfural Degradates (2-furoic acid).

OCSPP 

Guideline 

Data 

Requirement 

Submitted 

Studies 

(MRID) 

Study 

Classifications

Are data 

needed to 

conduct risk 

assessment?

Justification and Assumptions EPA 

will Make in Absence of Data 

835.1230 Adsorption/ 

desorption (batch 

equilibrium) 

47105103 Acceptable No Study partially fulfills the 835.1230 data 

requirement by providing mobility data 

for 2-furoic acid. 

835.4100 Aerobic Soil Metabolism7 and 835.4200 Anaerobic Soil Metabolism: New aerobic 

soil and anaerobic soil metabolism studies were required as part of the conditional registration of 

furfural. The available studies, which have been deemed supplemental, provide limited 

information, or there is uncertainty, with respect to the formation of major transformation 

products of furfural: furfuryl alcohol and 2-furoic acid. Despite these uncertainties, the studies 

were used in the previous screening-level assessments of the new uses on turf and ornamentals, 

sod farms and athletic fields. In order to address this uncertainty, the studies should closely 

monitor the transformation products in addition to the parent compound, and avoid problems 

observed in the previous studies. They should supply appropriate data about the fate and 

persistence of furfural and its transformation products, resulting in a better characterization and 

understanding of the metabolism of this chemical. The data will be used in re-estimating the 

input parameters to be used in the aquatic exposure models. Three aerobic and four anaerobic 

soils are required. In the absence of the additional data, EFED may make conservative 

assumptions about the persistence of furfural and its degradates in soil systems. 

835.4300 Aerobic Aquatic Metabolism: There is lack of knowledge about the fate and 

persistence of furfural and its transformation products in aquatic systems. This knowledge is 

 

7

 Study MRID No. 49583601 is currently in review. This study may be used to fulfill the data request, but 

determination of this is pending. Therefore, the request for the aerobic soil metabolism study still exists at this time. 
28 

needed for an appropriate aquatic exposure modeling using the SWCC model. In the absence of 

the additional data, EFED may make conservative assumptions about the persistence of furfural 

and its degradates in aquatic systems. 

Non-guideline Laboratory Investigation of Subsurface Degradation Study: A study to 

investigate the fate of furfural in the vadose zone below top soil is needed in order to refine the 

Estimated Drinking Waters Concentrations (EDWCs). The current PRZM-GW accounts for 

aerobic biodegradation in top soil and hydrolysis degradation in the aquifer. Since furfural is 

stable under hydrolysis is stable, the model assumes no degradation below the top 1-meter level. 

The subsurface study will help in refinement of the groundwater EDWCs. The study should 

examine the fate of furfural and its degradate furfuryl alcohol to address the constituents of 

concern for the human health drinking water assessment. A protocol should be submitted to the 

Agency prior to conduct of the study. 

b. Effects 

Table 10 identifies ecological effects studies by MRID that offer data for each guideline 

requirement, as well as study classifications and whether or not further data are needed in order 

to support risk assessment. Rationale for the additional data requested is presented below the 

tables. 

Table 10. Submitted Ecological Effects Data for Furfural. 

Guideline 

# Data Requirement 

Are 

Additional 

Data 

Needed for 

Risk 

Assessment

? MRID #’s 

Study 

Classification 

Justification and 

Assumptions EPA will 

Make in Absence of Data - 

Some Example texts are 

include 

850.2100 Avian Acute Oral* N 

46343004 A 

Waived due to primary 

exposure being via 

inhalation (D410714) 

46343003 S 

47035302 A 

------ 

Avian Acute 

Inhalation N 48120801 A 

850.2200 Avian Dietary–quail N 48120802 A   

850.2200 Avian Dietary–

mallard N ----------- ------------- 

Furfural was found to be 

moderately toxic to Mallard 

duck on an acute basis. The 

volatility of furfural 

suggests that it will either 

be incorporated into the 

field or volatilized soon 

after application so 

exposure will be low. 
29 

Table 10. Submitted Ecological Effects Data for Furfural. 

Guideline 

# Data Requirement 

Are 

Additional 

Data 

Needed for 

Risk 

Assessment

? MRID #’s 

Study 

Classification 

Justification and 

Assumptions EPA will 

Make in Absence of Data - 

Some Example texts are 

include 

850.2300 

Avian 

Reproduction N NA NA 

Waived - DP Barcode 

D399351. The feasibility of 

conducting this study due to 

volatility of furfural would 

not realistically simulate 

field exposure and would 

therefore not provide 

meaningful data to be used 

in a risk assessment. 

850.1075 

Fish Acute 

Toxicity–bluegill N 46207301 A   

850.1075 

Fish Acute 

Toxicity–rainbow 

trout N 46343002 S   

850.1075 

Fish Acute Toxicity 

– fathead minnow N 48873301 A   

850.101 

Aquatic Invertebrate 

Acute Toxicity–

freshwater N 46343001 A   

850.1075 

Marine/Estuarine 

Acute Toxicity–Fish N 46426509 A   

850.1025 

Marine/Estuarine 

Acute Toxicity–

Mollusk (shell 

deposition) N 46426507 A   
30 

Table 10. Submitted Ecological Effects Data for Furfural. 

Guideline 

# Data Requirement 

Are 

Additional 

Data 

Needed for 

Risk 

Assessment

? MRID #’s 

Study 

Classification 

Justification and 

Assumptions EPA will 

Make in Absence of Data - 

Some Example texts are 

include 

850.1035 

Marine/Estuarine 

Acute Toxicity–

Shrimp* Y 46426508 S 

This study was conducted 

with larvae that were older 

than guidelines (5-day vs 

<24 hr) Additional data 

would help reduce 

uncertainty about toxicity 

of furfural to mysid shrimp. 

850.14 

Fish Early Life 

Stage–freshwater N 47692201 S   

850.14 

Fish Early Life 

Stage– 

marine/estuarine N 49048802 A   

850.13 

Aquatic Invertebrate 

Life Cycle–

freshwater N 47035301 A   

850.135 

Aquatic Invertebrate 

Life Cycle–

saltwater N 49048801 A   

850.41 

Seedling 

Germination/Seedli

ng Emergence–Tier 

II N 47701204 A   

850.415 

Vegetative Vigor–

Tier II N 47720301 A   

Nonguideline Vegetative Vigor–

Vapor Phase* Y ------------ ------------ 

This study enables vapor 

phase risk assessment 

specific to offsite plants 

since furfural is a volatile 

chemical with multiple 

applications per season. 

Risk will be presumed in 

absence of the data. A 

protocol may be submitted 

for review. 

850.44 

Aquatic Plant 

Growth – Tier II 

(Lemna) N 47569401 S   

850.54 N 

47569402 S   

47569403 S   
31 

Table 10. Submitted Ecological Effects Data for Furfural. 

Guideline 

# Data Requirement 

Are 

Additional 

Data 

Needed for 

Risk 

Assessment

? MRID #’s 

Study 

Classification 

Justification and 

Assumptions EPA will 

Make in Absence of Data - 

Some Example texts are 

include 

Aquatic Plant 

Growth – Tier II 

(algae) 

47569404 S   

47569405 S   

Nonguideline Honeybee Acute 

Vapor* Y ------------ ------------ 

This study enables vapor 

phase risk assessment 

specific to bees since 

furfural is a volatile 

chemical with multiple 

applications per season. 

Risk will be presumed in 

absence of the data. A 

protocol may be submitted 

for review. 

Nonguideline Honeybee Acute 

Oral N 46331505 A   

850.302 

Honeybee Acute 

Contact N 47300201 A   

A=Acceptable; S=Supplemental; U=Unacceptable; W=Waived; N/A=Not Applicable; NA=Not Available; 

Inv.=Invalid; R=Potentially Repairable 

*Description of studies needed to fill data gaps are below by guideline number. 

850.1035 Estuarine/Marine Acute Toxicity- Shrimp: This study (MRID 46426508) is 

currently considered Supplemental. If data that indicates that 5 day old mysids are in fact 

more susceptible than <24 hour old mysids to Furfural, this study may be upgraded to 

Acceptable. In addition, data indicating that all test mysids completed at least one complete 

molt cycle during the 96 hour exposure should also be submitted. 

Non-Guideline Vegetative Vigor Vapor-Phase Toxicity Study: Furfural is a highly volatile 

chemical and used in quantities that may result in exposure to terrestrial plants via off-site 

transport in the vapor phase. 

Non-guideline Laboratory Investigation acute vapor phase toxicity study with the honey 

bee: The current estimate of terrestrial invertebrate risk relies on estimated acute contact toxicity 

with the honeybee. This study will enable a vapor phase risk assessment specific to bees since 

furfural is a volatile chemical with multiple applications per season. 
32 

Guideline Number: N/A (Non-Guideline Study) 

Study Title: Laboratory Investigation of Subsurface Degradation 

Rationale for Requiring the Data 

A study to investigate the fate of furfural in the vadose zone below top soil is needed in order to refine the 

Estimated Drinking Waters Concentrations (EDWCs) for the human health assessment. The current PRZM-GW 

accounts for aerobic biodegradation in top soil and hydrolysis degradation in the aquifer. Since furfural is stable 

under hydrolysis is stable, the model assumes no degradation below the top 1-meter level. The subsurface study 

will help in refinement of the groundwater EDWCs. The study should examine the fate of furfural and its 

degradate furfuryl alcohol to address the constituents of concern for the human health drinking water assessment. 

A protocol should be submitted to the Agency prior to conduct of the study. 

Practical Utility of the Data 

How will the data be used? 

The subsurface study will help in refinement of the groundwater EDWCs. . 

How could the data impact the Agency’s future decision-making? 

If future ecological risk assessments are performed without these data, the Agency would have to use 

conservative assumptions related to the persistence of furfural below the surface soil layer. Such assumptions 

may lead to conservative estimated exposure concentrations of furfural and its degradate furfuryl alcohol in 

ground water which can lead to risks of concern for drinking water in the human health assessment. The lack of 

these data will limit the flexibility the Agency and registrants have in mitigating potential risks and could result in 

use restrictions for furfural that are unnecessarily severe. 

Guideline Number: N/A (Non-Guideline Study) 

Study Title: Vegetative Vigor Vapor Exposure Study 

Rationale for Requiring the Data 

Due to the fate properties of furfural, in particular its high volatility, it is expected that plants will be exposed to 

furfural in the vapor phase during off-site movement of vapors. The current vegetative vigor study (MRID 

47720301) demonstrates plant sensitivity of both monocots and dicots to furfural. No data are available to 

account for plant exposure to vapor phase pesticides. Therefore, to assess risks of furfural to plants when plants 

are exposed to furfural vapors, EFED recommends that the Agency require a non-guideline vegetative vigor 

study to be conducted with vapor exposure to furfural. In the absence of such data, insufficient information exists 

to preclude concerns for direct toxic effects to non-target plant species. 

Practical Utility of the Data 

How will the data be used? 

Data from a vegetative vigor vapor phase study will be used to determine the potential for furfural to affect nontarget terrestrial plants in the terrestrial environment. In the absence of vapor exposure data specific for terrestrial 

plants, risk to terrestrial plants, including listed species, will be assumed. If the terrestrial plant special study 

shows that furfural exceeds the Agency’s level of concern for federally listed or other terrestrial plant species, the 

Agency may be able to use this data to mitigate risks. 

How could the data impact the Agency’s future decision-making? 

If future ecological risk assessments are performed without these data, the Agency would have to presume risk to 

non-target terrestrial plants from use of furfural. Therefore, use of furfural and its formulated products may need 
33 

to be restricted in areas where terrestrial plants could be exposed. The lack of these data will limit the flexibility 

the Agency and registrants have in mitigating potential risks and could result in use restrictions for furfural that 

are unnecessarily severe. 

Guideline Number: N/A(Non-Guideline Study) 

Study Title: Acute Honey Bee Vapor Exposure Study 

Rationale for Requiring the Data 

Due to the fate properties of furfural, in particular its high volatility, it is expected that honey bees and other 

insect pollinators will be exposed to furfural in the vapor phase. Neither of the standard Tier I toxicity studies 

with honey bees (i.e., acute contact or acute oral toxicity study for honey bees) account for exposure to vapor 

phase pesticides. Therefore, to assess risks of furfural to bees, EFED recommends that the Agency require a nonguideline acute honey bee vapor exposure study for furfural, to be conducted in lieu of the normally required 

acute honey bee contact study that would fulfill guideline 850.3020 and the newly proposed requirements for oral 

toxicity tests including adult and larval honey bees. 

Practical Utility of the Data 

How will the data be used? 

Data from an acute honey bee vapor exposure study will be used to determine the potential for furfural to affect 

non-target terrestrial invertebrates in the terrestrial environment. Of particular interest is quantification of a 

toxicity endpoint, i.e., a 4-hour LC50, that can be used to derive risk quotients. In the absence of vapor exposure 

data specific for honey bees, risk to terrestrial invertebrates, including listed species, will be assumed. 

How could the data impact the Agency’s future decision-making? 

If future ecological risk assessments are performed without these data, the Agency would have to presume risk to 

non-target terrestrial invertebrates, including honey bees, from use of furfural. Therefore, use of furfural and its 

formulated products may need to be restricted in areas where terrestrial invertebrates, including honey bees, 

could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in mitigating 

potential risks and could result in use restrictions for furfural that are unnecessarily severe. 

13. References 

Armitage, J.M., & Gobas, F.A.P.C. 2007. A terrestrial food-chain bioaccumulation model for 

POPs. Environmental Science and Technology, 41, 4019-4025. 

Bansal, R.K. 1999. Heterocyclic Chemistry, 3rd Edition, New Age International Publishers, New 

Delhi, India, p. 188 (available at Google Books, accessed 08/12/09). 

Bierbach, A., I. Barnes and K.H. Becker. 1995. Product and Kinetic Study of the OH-Initiated 

Gas-Phase Oxidation of Furan, 2-Methylfuran and Furanaldehydes at ≈300K. 

Atmospheric Environ. Vol. 29, No. 19. pp. 2651-2660. 
34 

Food and Agriculture Organization of the United Nations. 2000. FAO PESTICIDE DISPOSAL 

SERIES 8. Assessing Soil Contamination: A Reference Manual. Appendix 2. 

Parameters of pesticides that influence processes in the soil. Editorial Group, FAO 

Information Division: Rome, 2000. 

http://www.fao.org/DOCREP/003/X2570E/X2570E00.htm. 

Gobas, F.A.P.C., B.C. Kelly and J.A. Arnot. 2003. Quantitative structure activity relationships 

for predicting the bioaccumulation of POPs in terrestrial food webs. QSAR Comb. Sci. 

22:329-336. 

USEPA. 2004. Overview of the Ecological Risk Assessment Process in the Office of Pesticide 

Programs. United States Environmental Protection Agency (USEPA). Environmental 

Fate and Effects Division. Office of Pesticide Programs. Available at 

http://www.epa.gov/espp/consultation/ecorisk-overview.pdf (accessed 01/21/2015). 

USEPA. 2006. NAFTA Guidance Document for Conducting Terrestrial Field Dissipation 

Studies. EFED/Office of Pesticide Programs and PMRA/Environmental Assessment 

Division. Available at 

http://www.epa.gov/oppefed1/ecorisk_ders/terrestrial_field_dissipation.htm (accessed 

01/21/2015). 

USEPA 2008. OPPTS 835.6100 Terrestrial Field Dissipation. EPA 712-C-08-020. October 

2008. Office of Prevention, Pesticides, and Toxic Substances. United States 

Environmental Protection Agency. 

USEPA. 2010a. Guidance for Reporting on the Environmental Fate and Transport of the 

Stressors of Concern in Problem Formulations for Registration Review, Registration 

Review Risk Assessments, Listed Species Litigation Assessments, New Chemical Risk 

Assessments, and Other Relevant Risk Assessments. Memorandum from Donald Brady 

dated January 25, 2010. Available at 

http://www.epa.gov/pesticides/science/efed/policy_guidance/team_authors/endangered_

species_reregistration_workgroup/esa_reporting_fate.htm. 

USEPA. 2010b. Furfural: Environmental Fate and Ecological Risk Assessment of Proposed 

Uses on Turf and Ornamentals. Office of Pesticide Programs/Environmental Fate and 

Effects Division (DP Barcodes D346394, D346397, D349292, D373440, & D374496, 

dated 04/05/2010). 

USEPA. 2010c. Furfural. Human Health Risk Assessment for Use on Golf Course Turf (Tees 

and Greens) and Sod Farms. Office of Pesticide Programs/Health Effects Division (DP 

Barcode D315992, February 18, 2010). 

USEPA. 2012a. Section 3 Environmental Risk Assessment for Furfural (PC Code 043301) 

Proposed New Use on Athletic Fields (DP Barcode: D389908). Office of Pesticide 

Programs/Environmental Fate and Effects Division (DP Barcode D389908, dated 

01/17/2012). 
35 

USEPA. 2012b. Section 3 Environmental Risk Assessment for Furfural (PC Code 043301) 

Proposed New Use on Ornamentals and Clarification of Risks on Existing Uses on Turf 

(Including Golf Course Tees and Greens and Sod Farms). Office of Pesticide 

Programs/Environmental Fate and Effects Division (DP Barcode D389903, dated 

05/07/2012). 

USEPA. 2014. Review of the Proposed Protocol for the Aerobic Soil Metabolism Study, 

Response to Requested Waiver for the Anaerobic Soil Metabolism Study, and Review of 

the Expression of the Total Toxic Residues Including Furfural and Furfuryl Alcohol. 

Office of Pesticide Programs/Environmental Fate and Effects Division (DP Barcodes 

D413998, D418064, dated May 5, 2014). 

__________________________________ 

Appendix D provides a list of environmental fate and ecological effects studies submitted to the 

Agency.
36 

Appendix A. Furfural and Its Transformation ProductsTable A1. Furfural and Its Major Environmental Degradates

Code Name/ Synonym Chemical Name Chemical Structure Study Type Ref. (MRID) Max

%AR 

Furfural 2-Furaldehyde; 

2-Furancarboxaldehyde SMILES String:O=CC(OC=C1)=C1 CAS No.: 98-01-1 Formula: C5H4O2MW: 96.085 g/mol 

Parent Compound 

TRANSFORMATION PRODUCTS 

2-Furoic acid 2-Furancarboxylic acid 

CAS Number: 88-14-2 SMILES String:O=C(O)C(OC=C1)=C1 Formula: C5H4O3MW: 112.09 g/mol 

Aerobic soil 

46011007, 46510602, 

46523701 

51-53% 

Aerobic soil 47105101 31.93

Anaerobic soil 

46426502, 46966001, 

46966002 

15.1% a

in water 

soil, res

Terr dissipation 47701201 94% 

Furfuryl alcohol 2-furanmethanol

CAS Number: 98-00-0 SMILES String:C1=CC=C(O1)CO[H] Formula: C5H6O2

MW: 98.10 g/mol 

Aerobic soil 

46011007, 46510602, 

46523701 

N

Aerobic soil 47105101 14.65% 

Anaerobic soil 

46426502, 46966001, 

46966002 

34.4% 

wate

Terr dissipation 47701201 12.7% 

O

O

H

O

O

OH
37 

Code Name/ Synonym Chemical Name Chemical Structure Study Type Ref. (MRID) Max

%AR 

2-Ketoglutaric acid -Ketoglutaric acid, 2- oxo-pentanedioic acid 

CAS Number: 328-50-7 SMILES String:O=C(O)C(=O)CCC(=O)O

Aq photolysis 

46011005, 46426501, 

46523601 

14.4% 

pH 

Succinic Acid Butanedioic acid 

CAS Number: 110-15-6 SMILES String:O=C(O)CCC(=O)O 

Aq photolysis 

46011005, 46426501, 

46523601 

55.4% 

pH 

Malonic Acid Propanedioic acid 

CAS Number: 141-82-2 SMILES String:O=C(O)CC(=O)O 

Aq photolysis 

46011005, 46426501, 

46523601 

17.4% 

pH 

Propionic Acid Propionic Acid 

CAS Number: 79-09-4 SMILES String:O=C(O)CC 

Aq photolysis 

46011005, 46426501, 

46523601 

12.5% 

pH 

Anaerobic soil 

46426502, 46966001, 

46966002 

26.0% 

la

Acetic acid Acetic acid 

CAS Number: 64-19-7 SMILES String:O=C(O)C 

Anaerobic soil 

46426502, 46966001, 

46966002 

52.4% a

in water 

soil, res

Formic Acid Formic Acid 

CAS Number: 64-18-6 SMILES String: O=CO 

Aq photolysis 

46011005, 46426501, 

46523601 

9.81% 

pH 

ND means not detected; NA means not available. 1 Bolded values indicate a major degradate was formed or that a degradate is of toxicological significance 2 Only a limited number of samples were tested for degradates of furfural.
38 

Appendix B. Evaluation of the Toxic Residues for Furfural

-Excerpt from memo: DP Barcode D413998, dated May 5, 2014: 

Request to Include Only Furfural and Furfuryl Alcohol in the Total 

Toxic Residue (TTR) Expression 

Study ID, please refer to waiver request above. (MRID 49156901). 

In its request, the registrant cites that EFED included 2-furoic acid in the TTR calculations for 

the first time in May 2012. It goes on to state that this inclusion conflicts with the HED 

determination of TTR where HED includes only parent furfural and furfuryl alcohol. It 

concludes by listing the reasons that 2-furoic acid was not included in a ROCKS determination. 

There is currently no registrant submitted data with which to characterize the acute and chronic 

toxicity of 2-furoic acid to aquatic taxa. Estimates of toxicity in the absence of data can be made 

using the ECOSAR module (v1.11) of EpiSuite (v 4.0). ECOSAR is a quantitative structure 

activity relationship (QSAR) tool that uses information on the structure of a chemical to predict 

toxicity based on a given dataset of endpoints associated with ECOSAR classes. There is some 

uncertainty with ECOSAR estimates as some classes are associated with more data points than 

others. 

To get an indication of how well ECOSAR estimates will apply to furfural and its degradates, 

parent furfural was analyzed in ECOSAR and the estimates were compared to registrant 

submitted data. 

Table 2 below shows the ECOSAR estimates for parent furfural as compared to the registrant 

submitted data. The results indicate that the estimates derived from the only ECOSAR class that 

yielded results for parent (aldehydes) are generally within one order of magnitude of the 

registrant submitted data. In the case of acute freshwater invertebrates, chronic freshwater 

invertebrates, acute estuarine/marine fish, and freshwater green algae, the estimates are generally 

separated by no more than a factor of three. One exception are the results of the chronic 

freshwater fish study, where the registrant submitted study on parent furfural was two orders of 

magnitude more sensitive than the ECOSAR estimate. 

The ECOSAR results of 2-furoic acid indicate that this degradate is at least 2 orders of 

magnitude less toxic than parent furfural depending on the exposure duration and taxa of 

concern. In some cases, 2-furoic acid is estimated to be 3 orders of magnitude less toxic than 

parent. Furthermore, as the registrant notes in its request, a prior ChemSAC meeting determined 

that 2-furoic acid would be ionized at a neutral pH and would have little potential to 

bioaccumulate. Based on this analysis, the request to exclude 2-furoic acid from the TTR and to 

only include parent furfural and furfuryl alcohol is granted. 
39 

Table 2. ECOSAR estimates for parent furfural and 2-furoic acid 

Test 

substance 

(ECOSAR 

class) 

Toxicity endpoints (mg a.i/L) 

Acute 

FW Fish 

LC50

Acute 

FW 

Invert 

EC50

Chronic 

FW Fish 

NOAEC 

Chronic FW 

Invert 

NOAEC 

Acute 

E/M 

Fish 

LC50

Acute 

E/M 

Invert 

LC50

Green 

algae 

EC50 

Furfural 

(registrant 

submitted 

studies) 

3.06 20.4 0.038 1.90 14.0 15.0 43.0 

Furfural 

(ECOSAR - 

Aldehydes) 

22.5 64.8 5.38 7.591 21.3 76.0 

2-furoic-acid 

(neutral 

organics-acid) 

7336 3797 643 286 9181 13465 1928 

1

Indicates that this estimate was obtained using an acute-to-chronic ratio (ACR)
40 

Appendix C. Evaluation Drinking Water Exposure Pathway for Birds 

and Mammals

Figure C-1. SIP evaluation for furfural. 

Table 1. Inputs 

Parameter Value 

Chemical name furfural 

Solubility (in water at 25oC; mg/L) 78100 

 

Mammalian LD50 (mg/kg-bw) 107 

Mammalian test species laboratory rat 

Body weight (g) of "other" 

mammalian species 

 

Mammalian NOAEL (mg/kg-bw) 10 

Mammalian test species laboratory rat 

Body weight (g) of "other" 

mammalian species 

 

Avian LD50 (mg/kg-bw) 85 

Avian test species northern bobwhite quail 

Body weight (g) of "other" avian 

species 

Mineau scaling factor 

 

Mallard NOAEC (mg/kg-diet) 

Bobwhite quail NOAEC (mg/kg-diet) 4930 

NOAEC (mg/kg-diet) for other bird 

species 

Body weight (g) of other avian 

species 

NOAEC (mg/kg-diet) for 2nd other 

bird species 

Body weight (g) of 2nd other avian 

species 

 

Table 2. Mammalian Results 

Parameter Acute Chronic 

Upper bound exposure (mg/kg-bw) 13433.2000 13433.2000 

Adjusted toxicity value (mg/kg-bw) 82.3002 7.6916 

Ratio of exposure to toxicity 163.2220 1746.4754 

Conclusion* 

Exposure through 

drinking water alone is 

a potential concern for 

mammals 

Exposure through drinking water 

alone is a potential concern for 

mammals 

 
41 

Table 3. Avian Results 

Parameter Acute Chronic 

Upper bound exposure (mg/kg-bw) 63261.0000 63261.0000 

Adjusted toxicity value (mg/kg-bw) 756.5000 524.0507 

Ratio of exposure to acute toxicity 83.6233 120.7154 

Conclusion* 

Exposure through 

drinking water alone is 

a potential concern for 

birds 

Exposure through drinking water 

alone is a potential concern for 

birds 

 

*Conclusion is for drinking water exposure alone. This does not combine all routes of exposure. 

Therefore, when aggregated with other routes (i.e., diet, inhalation, dermal), pesticide exposure 

through drinking water may contribute to a total exposure that has potential for effects to non-target 

animals. 

 
42 

Figure C-2. STIR evaluation for furfural. 

Welcome to the EFED 

Screening Tool for Inhalation Risk 

This tool is designed to provide the risk assessor with a rapid method for determining the potential 

significance of the inhalation exposure route to birds and mammals in a risk assessment. 

 

Input 

Application and Chemical Information 

Enter Chemical Name Furfural 

Enter Chemical Use Fumigant 

Is the Application a Spray? (enter y or n) n 

If Spray What Type (enter ground or air) ground 

Enter Chemical Molecular Weight (g/mole) 96.085 

Enter Chemical Vapor Pressure (mmHg) 2.60E+00 

Enter Application Rate (lb a.i./acre) 416.4 

 

Toxicity Properties 

Bird 

Enter Lowest Bird Oral LD50 (mg/kg bw) 85 

Enter Mineau Scaling Factor 1.15 

Enter Tested Bird Weight (kg) 0.178 

Mammal 

Enter Lowest Rat Oral LD50 (mg/kg bw) 107 

Enter Lowest Rat Inhalation LC50 (mg/L) 0.54 

Duration of Rat Inhalation Study (hrs) 4 

Enter Rat Weight (kg) 0.35 

 

Output 

Results Avian (0.020 kg ) 

Maximum Vapor Concentration in Air at Saturation 

(mg/m3) 1.34E+04 

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 1.69E+03 

Adjusted Inhalation LD50 2.39E+00 

Ratio of Vapor Dose to Adjusted Inhalation LD50 7.07E+02 Proceed to Refinements 

Maximum Post-treatment Spray Inhalation Dose (mg/kg) not applicable 

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 not applicable not applicable 

 

Results Mammalian (0.015 kg ) 

Maximum Vapor Concentration in Air at Saturation 

(mg/m3) 1.34E+04 

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 2.12E+03 
43 

Adjusted Inhalation LD50 3.21E+01 

Ratio of Vapor Dose to Adjusted Inhalation LD50 6.61E+01 Proceed to Refinements 

Maximum Post-treatment Spray Inhalation Dose (mg/kg) not applicable 

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 not applicable not applicable 
44 

Appendix D. Furfural Environmental Fate and Ecological Effects 

Studies Submitted to the Agency

Chemical Fate Bibliography 

161-1 Hydrolysis 

MRID Citation Reference 

4601100

4 

McLaughlin, S. (2003) (Carbon 14) Furfural- Determination of pH Dependent Hydrolysis. 

Project Number: 13782/6101. Unpublished study prepared by Springborn Smithers 

Laboratories. 80 p. 

161-2 Photodegradation-water 

MRID Citation Reference 

46011005 McLaughlin, S. (2003) (Carbon 14)Furfural - Determination of Photodegradation in an 

Aqueous Solution: Interim Report. Project Number: 13782/6103. Unpublished study 

prepared by Springborn Smithers Laboratories. 116 p. 

46426501 McLaughlin, S. (2004) [14-C]Furfural - Determination of Photodegradation in an Aqueous 

Solution and Separation, Isolation and Identification of Photoproducts Present at Less Than 

or Equal to 10% of Applied Dose. Project Number: 13782/6103. Unpublished study 

prepared by Springborn Smithers Laboratories. 198 p. 

46523601 Kovacs, M. (2005) Response to EFED/ERB#4 6/8/2004 Comments in DER (DP Barcode 

D295312) on the Phototransformation in Water of Furfural. Unpublished study prepared by 

Toxcel LLC. 6 p. 

162-1 Aerobic soil metabolism 

MRID Citation Reference 

4601100

7 

Gledhill, W. (2003) (Carbon 14)Furfural - Aerobic Soil Metabolism Study. Project Number: 

13782/6100. Unpublished study prepared by Springborn Smithers Laboratories. 112 p. 

4651060

2 

Kovacs, M. (2005) Supporting Data from "Aerobic Soil Metabolism Study of Furfural" 

(MRID# 46011007) Referenced as Attachments A through I in Volume 1: Response to 

EFED/ERD #4 in July 14, 2004 Comments in DER (DP Barcode D295312), Completed 

March 29, 2005. Project Number: 13782/6100. Unpublished study prepared by Toxcel LLC. 

105 p. 
45 

4652370

1 

Kovacs, M. (2005) Response to EFED/ERB #4 July 14, 2004 Comments in DER (DP 

Barcode D295312) on the Aerobic Biotranformation of Furfural in Soil. Unpublished study 

prepared by Toxcel LLC. 19 p. 

4710510

1 

Gledhill, W. (2007) (Carbon-14) Furfural: Aerobic Soil Metabolism: Supplemental Study. 

Project Number: 13782/6126. Unpublished study prepared by Springborn Smithers 

Laboratories. 113 p. 

4710510

1 Chemical Structures for parent and degradates from Aerobic soil metabolism study 

4859190

2 

Eickhoff, J. (2011) Waiver Request for an Additional Aerobic Soil Metabolism Study: 

Furfural. Unpublished study prepared by Agriguard Company, LLC. 8p. 

162-2 Anaerobic soil metabolism 

MRID Citation Reference 

4642650

2 

Gledhill, W. (2004) [14-C] Furfural - Anaerobic Soil Metabolism Study. Project Number: 

13782/6110. Unpublished study prepared by Springborn Smithers Laboratories. 161 p. 

4696600

1 

Kovacs, M. (2006) Response to EFED/ERB V February 9, 2006 Comments in DER (DP 

Barcode D315991) on the Anaerobic Soil Metabolism Study for Furfural. Unpublished study 

prepared by ToXcel, LLC. 12 p. 

4696600

2 

Kovacs, M. (2006) Supporting Data from "Anaerobic Soil Metabolism Study of Furfural. 

Unpublished study prepared by ToXcel, LLC. 227 p. 

163-1 Leach/adsorption/desorption 

MRID Citation Reference 

46011006 McLaughlin, S. (2003) (Carbon 14)Furfural - Determination of Batch Equilibrium Adsorption 

and Desorption Coefficients. Project Number: 13782/6102. Unpublished study prepared by 

Springborn Smithers Laboratories. 119 p. 

46523801 Kovacs, M. (2005) Response to EFED/ERB#4 7/18/2004 Comments in DER (DP Barcode 

D295312) on the Adsorption/Desorption (Batch Equilibrium) Study (MRID# 46011006) of 

Furfural. Unpublished study prepared by Toxcel LLC. 59 p 

. 

46523802 Kovacs, M. (2005) Data Waiver Request - Soil Column Leaching Study. Unpublished study 

prepared by Toxcel LLC. 9 p. 

47105103 McLaughlin, S. (2007) 2-Furoic Acid-Determining Batch Equilibrium Adsorption and 

Desorption Coefficients Following FIFRA Guildlines 163-1. Project Number: 13782/6124. 

Unpublished study prepared by Springborn Smithers Laboratories. 113 p. 

47105103 Chemical physical/chemical properties from 47105103 

47105104 McLaughlin, S. (2006) Furfural Technical-Determination of the K(oc) Coefficient Following 

OECD Guideline 121. Project Number: 13782/6121. Unpublished study prepared by 

Springborn Smithers Laboratories. 39 p. 
46 

47115401 McLaughlin, S. (2005) [Carbon-14]Furfural - Determination of Batch Equilibrium Adsorption 

and Desorption Coefficients. Project Number: 13782/6102. Unpublished study prepared by 

Springborn Smithers Laboratories. 122 p. 

47875801 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Georgia: Supplement. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 436 p. 

163-2 Volatility - lab 

MRID Citation Reference 

4600930

4 

Kovacs, M. (2003) Multiguard Protect - Laboratory Volatility. Project Number: 

MG/PROTECT/2003/NFG/05. Unpublished study prepared by Toxcel LLC. 16 p. 

4601100

8 

Kovacs, M. (2003) Furfural Technical - Laboratory Volatility. Project Number: 

FURFURAL/2003/NFG/09. Unpublished study prepared by Toxcel LLC. 16 p. 

4610630

1 

Gledhill, W. (2003) (Carbon 14) Multiguard Protect - Volatility from Soil Under Laboratory 

Conditions. Project Number: 13782/6109. Unpublished study prepared by Springborn 

Smithers Laboratories. 82 p. 

4652390

1 

Kovacs, M. (2005) Response to EFED/ERB#4 6/15/2004 Comments in DER (DP Barcode 

D298145) on the Laboratory Volatility of Furfural from Soil. Unpublished study prepared by 

Toxcel LLC. 3 p. 

4675840

1 

Gledhill, W. (2006) Raw Data Supplement to (Carbon 14)Multiguard Protect - Volatility from 

Soil Under Laboratory Conditions (MRID # 46106301) Original Report Submitted on October 

27, 2003 in Support of Furfural Technical. Project Number: 13782/6109. Unpublished study 

prepared by Springborn Smithers Laboratories. 20 p. 

163-3 Volatility - field 

MRID Citation Reference 

47483901 Brewer, L.; Reynolds, M. (2008) Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground 

and Turf Grass in Central California: Final Report. Project Number: 13782/6128A, HC/001, 

102507A/E. Unpublished study prepared by Springborn Smithers Laboratories. 323 p. 

47569101 Brewer, L.; Reynolds, M. (2008) Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (A.I.)] to Bare Ground and 

Turf Grass in Georgia. Project Number: 13782/6128A, 

102507/A/E/FATE/FIFRA/N/164/163/3. Unpublished study prepared by Springborn Smithers 

Laboratories. 345 p. 

47701202 Brewer, L.; Reynolds, M. (2009) Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and 
47 

Turf Grass in Central California: Final Report. Project Number: 13782/6128A, 102507A/E. 

Unpublished study prepared by Springborn Smithers Laboratories. 326 p. 

47253701 Wilson, T. (2007) Detection of Furfural (Multiguard Protect) in Greenhouse Air Using Low 

Volume Air Sampling with Sorbent Trapping and Chemical Analysis. Project Number: 62216. 

Unpublished study prepared by ABC Laboratories, Inc. 151 p. 

47253702 Wilson, T. (2007) Method Validation of Furfural Capture and Analysis in Greenhouse Air 

Using Low Volume Air Sampling, Sorbent Trapping, and HPLC Analysis. Project Number: 

50536. Unpublished study prepared by ABC Laboratories, Inc. 127 p. 

47569101 Brewer, L.; Reynolds, M. (2008) Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (A.I.)] to Bare Ground and 

Turf Grass in Georgia. Project Number: 13782/6128A, 

102507/A/E/FATE/FIFRA/N/164/163/3. Unpublished study prepared by Springborn Smithers 

Laboratories. 345 p. 

47701201 Brewer, L.; Reynolds, M.; Kovacs, M. (2009) Dissipation of Furfural, 2-Furoic Acid and 

Furfuryl Alcohol from Soil and Turf Following Applications of Multiguard Protect [90% 

Furfural as Active Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California and 

Georgia: Final Report. Project Number: 13782/6128A. Unpublished study prepared by 

Springborn Smithers Laboratories. 484 p. 

47701202 Brewer, L.; Reynolds, M. (2009) Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and 

Turf Grass in Central California: Final Report. Project Number: 13782/6128A, 102507A/E. 

Unpublished study prepared by Springborn Smithers Laboratories. 326 p. 

4787570

1 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 376 p. 

4787570

2 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 393 p. 

4787570

3 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 361 p. 

4787570

4 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 379 p. 

4787570

5 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 432 p. 
48 

4787570

6 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 420 p. 

4787570

7 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 241 p. 

4787570

8 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 385 p. 

4787570

9 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 293 p. 

4787571

0 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 417 p. 

4787571

1 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 382 p. 

4787571

2 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Central California. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 266 p. 

4787571

3 

Katz, A. (2009) Raw Analytical Data from the Study: California Air Cubic Meter Summary. 

Project Number: 13782/6128A. Unpublished study prepared by Springborn Smithers 

Laboratories. 54 p. 

4787580

2 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Georgia: Supplement. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 371 p. 

4787580

3 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Georgia: Supplement. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 343 p. 

4787580

4 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Georgia: Supplement. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 302 p. 

4787580

5 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 
49 

Bare Ground and Turf Grass in Georgia: Supplement. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 357 p. 

4787580

6 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Georgia: Supplement. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 263 p. 

4787580

7 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Georgia: Supplement. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 380 p. 

4787580

8 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Georgia: Supplement. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 415 p. 

4787580

9 

Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to 

Bare Ground and Turf Grass in Georgia: Supplement. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 208 p. 

4787581

0 

Katz, A. (2009) Raw Analytical Data from the Study: Georgia Air Cubic Meter Summary: 

(Furfural). Project Number: 13782/6128A. Unpublished study prepared by Springborn 

Smithers Laboratories. 37 p. 

4787780

2 

Katz, A. (2009) Raw Analytical Data - Field Notes for California Field Volatility Study: Volatility 

and Air Concentrations of Furfural Following Applications of Multiguard Protect [90% Furfural 

Active Ingredient (a.i.)] to Bare Ground and Turf Grass in California: Supplement to MRID 

47701202. Project Number: 13782/6128A, 1005707A/E. Unpublished study prepared by 

Springborn Smithers Laboratories. 136 p. 

4787780

3 

Katz, A. (2009) Raw Analytical Data - Field Notes for California Field Volatility Study: Volatility 

and Air Concentrations of Furfural Following Applications of Multiguard Protect [90% Furfural 

Active Ingredient (a.i.)] to Bare Ground and Turf Grass in California: Supplement to MRID 

47701202. Project Number: 13782/6128A, 1005707A/E. Unpublished study prepared by 

Springborn Smithers Laboratories. 139 p. 

4787780

4 

Katz, A. (2009) Raw Analytical Data - Field Notes for California Field Volatility Study: Volatility 

and Air Concentrations of Furfural Following Applications of Multiguard Protect [90% Furfural 

Active Ingredient (a.i.)] to Bare Ground and Turf Grass in California: Supplement to MRID 

47701202. Project Number: 1005707A/E, 13782/6128A. Unpublished study prepared by 

Springborn Smithers Laboratories. 120 p. 

4787780

5 

Katz, A. (2009) Raw Analytical Data - Field Notes for California Field Volatility Study: Volatility 

and Air Concentrations of Furfural Following Applications of Multiguard Protect [90% Furfural 

Active Ingredient (a.i.)] to Bare Ground and Turf Grass in California: Supplement to MRID 

47701202. Project Number: 13782/6128A, 1005707A/E. Unpublished study prepared by 

Springborn Smithers Laboratories. 122 p. 

4787780

6 

Katz, A. (2009) Raw Analytical Data - Field Notes for California Field Volatility Study: Volatility 

and Air Concentrations of Furfural Following Applications of Multiguard Protect [90% Furfural 

Active Ingredient (a.i.)] to Bare Ground and Turf Grass in California: Supplement to MRID 

47701202. Project Number: 1005707A/E, 13782/6128A. Unpublished study prepared by 

Springborn Smithers Laboratories. 108 p. 
50 

4787810

3 

Katz, A. (2009) Raw Analytical Data - Field Notes for Georgia Field Volatility Study: Volatility 

and Air Concentrations of Furfural Following Applications of Multiguard Protect [90% Furfural 

Active Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement to MRID 

47569101. Project Number: 13782/6128A. Unpublished study prepared by Springborn 

Smithers Laboratories. 69 p. 

4787810

4 

Katz, A. (2009) Raw Analytical Data - Field Notes for Georgia Field Volatility Study: Volatility 

and Air Concentrations of Furfural Following Applications of Multiguard Protect [90% Furfural 

Active Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement to MRID 

47569101. Project Number: 13782/6128A. Unpublished study prepared by Springborn 

Smithers Laboratories. 57 p. 

4787810

5 

Katz, A. (2009) Raw Analytical Data - Field Notes for Georgia Field Volatility Study: Volatility 

and Air Concentrations of Furfural Following Applications of Multiguard Protect [90% Furfural 

Active Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement to MRID 

47569101. Project Number: 13782/6128A. Unpublished study prepared by Springborn 

Smithers Laboratories. 56 p. 

4787810

6 

Katz, A. (2009) Raw Analytical Data - Field Notes for Georgia Field Volatility Study: Volatility 

and Air Concentrations of Furfural Following Applications of Multiguard Protect [90% Furfural 

Active Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement to MRID 

47569101. Project Number: 13782/6128A. Unpublished study prepared by Springborn 

Smithers Laboratories. 63 p. 

4788190

1 

Sullivan, D. (2009) Addendum to Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and 

Turf Grass in Central California. Project Number: 1005707A/E, 13782/6128A. Unpublished 

study prepared by Sullivan Environmental Consulting. 28 p. 

4789460

1 

Katz, A. (2009) Raw Analytical Data-Field Notes for Georgia Field Volatility Study: Valatility 

and Air Concentrations of Furfural Following Applications of Multiguard Protect [90% Furfural 

Active Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia. Project Number: 

13782/6128A, 07/37, 13782/6128A/GA. Unpublished study prepared by Springborn Smithers 

Laboratories. 120 p. 

4789460

2 

Katz, A. (2009) Raw Analytical Data-Field Notes for Georgia Field Volatility Study: Volatility 

and Air Concentration of Furfural Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 100 p. 

4789480

1 

Katz, A. (2009) Addendum to Volatility and Air Concentrations of Furfural Following 

Applications to Multigard Protect [90% Furfural Active Ingredient (a.i)] to Bare Ground and 

Turf Grass in Georgia: Final Report. Unpublished study prepared by Sullivan Environmental 

Consulting, Inc. 27 p. 

164-1 Terrestrial field dissipation 

MRID Citation Reference 

47483901 Brewer, L.; Reynolds, M. (2008) Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to Bare 
51 

Ground and Turf Grass in Central California: Final Report. Project Number: 

13782/6128A, HC/001, 102507A/E. Unpublished study prepared by Springborn 

Smithers Laboratories. 323 p. 

47569101 Brewer, L.; Reynolds, M. (2008) Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (A.I.)] to Bare 

Ground and Turf Grass in Georgia. Project Number: 13782/6128A, 

102507/A/E/FATE/FIFRA/N/164/163/3. Unpublished study prepared by Springborn 

Smithers Laboratories. 345 p. 

47701201 Brewer, L.; Reynolds, M.; Kovacs, M. (2009) Dissipation of Furfural, 2-Furoic Acid and 

Furfuryl Alcohol from Soil and Turf Following Applications of Multiguard Protect [90% 

Furfural as Active Ingredient (a.i.)] to Bare Ground and Turf Grass in Central 

California and Georgia: Final Report. Project Number: 13782/6128A. Unpublished 

study prepared by Springborn Smithers Laboratories. 484 p. 

47701202 Brewer, L.; Reynolds, M. (2009) Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to Bare 

Ground and Turf Grass in Central California: Final Report. Project Number: 

13782/6128A, 102507A/E. Unpublished study prepared by Springborn Smithers 

Laboratories. 326 p. 

47701201 Brewer, L.; Reynolds, M.; Kovacs, M. (2009) Dissipation of Furfural, 2-Furoic Acid and 

Furfuryl Alcohol from Soil and Turf Following Applications of Multiguard Protect [90% 

Furfural as Active Ingredient (a.i.)] to Bare Ground and Turf Grass in Central 

California and Georgia: Final Report. Project Number: 13782/6128A. Unpublished 

study prepared by Springborn Smithers Laboratories. 484 p. 

48708401 Sullivan, D.; Ajwa, H.; Sullivan, R.; et al. (2011) Monitoring of Flux from Soil Injection / 

Rotovation Application Method of Multiguard Protect (90% Furfural as Active 

Ingredient) on Bare Ground Applications in Florida. Project Number: AU/2011/09, 

SEC2011A. Unpublished study prepared by Sullivan Environmental Consulting, JRF 

America and Mirusso Enterprises, Inc. 368p. 

164-3 Forest field dissipation 

MRID Citation Reference 

47483901 Brewer, L.; Reynolds, M. (2008) Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to Bare 

Ground and Turf Grass in Central California: Final Report. Project Number: 

13782/6128A, HC/001, 102507A/E. Unpublished study prepared by Springborn 

Smithers Laboratories. 323 p. 

835.8100 Field volatility from soil 

MRID Citation Reference 

47569101 Brewer, L.; Reynolds, M. (2008) Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (A.I.)] to Bare 

Ground and Turf Grass in Georgia. Project Number: 13782/6128A, 

102507/A/E/FATE/FIFRA/N/164/163/3. Unpublished study prepared by Springborn 

Smithers Laboratories. 345 p. 

47701201 Brewer, L.; Reynolds, M.; Kovacs, M. (2009) Dissipation of Furfural, 2-Furoic Acid and 

Furfuryl Alcohol from Soil and Turf Following Applications of Multiguard Protect [90% 
52 

Furfural as Active Ingredient (a.i.)] to Bare Ground and Turf Grass in Central 

California and Georgia: Final Report. Project Number: 13782/6128A. Unpublished 

study prepared by Springborn Smithers Laboratories. 484 p. 

47701202 Brewer, L.; Reynolds, M. (2009) Volatility and Air Concentrations of Furfural Following 

Applications of Multiguard Protect [90% Furfural Active Ingredient (a.i.)] to Bare 

Ground and Turf Grass in Central California: Final Report. Project Number: 

13782/6128A, 102507A/E. Unpublished study prepared by Springborn Smithers 

Laboratories. 326 p. 

47875701 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 376 

p. 

47875702 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 393 

p. 

47875703 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 361 

p. 

47875704 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 379 

p. 

47875705 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 432 

p. 

47875706 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 420 

p. 

47875707 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 241 

p. 

47875708 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 385 

p. 
53 

47875709 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 293 

p. 

47875710 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 417 

p. 

47875711 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 382 

p. 

47875712 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Central California. Project Number: 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 266 

p. 

47875713 Katz, A. (2009) Raw Analytical Data from the Study: California Air Cubic Meter 

Summary. Project Number: 13782/6128A. Unpublished study prepared by Springborn 

Smithers Laboratories. 54 p. 

47875801 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement. Project 

Number: 13782/6128A. Unpublished study prepared by Springborn Smithers 

Laboratories. 436 p. 

47875802 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement. Project 

Number: 13782/6128A. Unpublished study prepared by Springborn Smithers 

Laboratories. 371 p. 

47875803 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement. Project 

Number: 13782/6128A. Unpublished study prepared by Springborn Smithers 

Laboratories. 343 p. 

47875804 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement. Project 

Number: 13782/6128A. Unpublished study prepared by Springborn Smithers 

Laboratories. 302 p. 

47875805 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement. Project 

Number: 13782/6128A. Unpublished study prepared by Springborn Smithers 

Laboratories. 357 p. 
54 

47875806 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement. Project 

Number: 13782/6128A. Unpublished study prepared by Springborn Smithers 

Laboratories. 263 p. 

47875807 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement. Project 

Number: 13782/6128A. Unpublished study prepared by Springborn Smithers 

Laboratories. 380 p. 

47875808 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement. Project 

Number: 13782/6128A. Unpublished study prepared by Springborn Smithers 

Laboratories. 415 p. 

47875809 Katz, A. (2009) Raw Analytical Data from the Study: Volatility and Air Concentrations 

of Furfural Following Applications of Multiguard Protect [90% Furfural Active 

Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia: Supplement. Project 

Number: 13782/6128A. Unpublished study prepared by Springborn Smithers 

Laboratories. 208 p. 

47875810 Katz, A. (2009) Raw Analytical Data from the Study: Georgia Air Cubic Meter 

Summary: (Furfural). Project Number: 13782/6128A. Unpublished study prepared by 

Springborn Smithers Laboratories. 37 p. 

47877802 Katz, A. (2009) Raw Analytical Data - Field Notes for California Field Volatility Study: 

Volatility and Air Concentrations of Furfural Following Applications of Multiguard 

Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in 

California: Supplement to MRID 47701202. Project Number: 13782/6128A, 

1005707A/E. Unpublished study prepared by Springborn Smithers Laboratories. 136 

p. 

47877803 Katz, A. (2009) Raw Analytical Data - Field Notes for California Field Volatility Study: 

Volatility and Air Concentrations of Furfural Following Applications of Multiguard 

Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in 

California: Supplement to MRID 47701202. Project Number: 13782/6128A, 

1005707A/E. Unpublished study prepared by Springborn Smithers Laboratories. 139 

p. 

47877804 Katz, A. (2009) Raw Analytical Data - Field Notes for California Field Volatility Study: 

Volatility and Air Concentrations of Furfural Following Applications of Multiguard 

Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in 

California: Supplement to MRID 47701202. Project Number: 1005707A/E, 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 120 

p. 

47877805 Katz, A. (2009) Raw Analytical Data - Field Notes for California Field Volatility Study: 

Volatility and Air Concentrations of Furfural Following Applications of Multiguard 

Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in 

California: Supplement to MRID 47701202. Project Number: 13782/6128A, 

1005707A/E. Unpublished study prepared by Springborn Smithers Laboratories. 122 

p. 

47877806 Katz, A. (2009) Raw Analytical Data - Field Notes for California Field Volatility Study: 

Volatility and Air Concentrations of Furfural Following Applications of Multiguard 
55 

Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in 

California: Supplement to MRID 47701202. Project Number: 1005707A/E, 

13782/6128A. Unpublished study prepared by Springborn Smithers Laboratories. 108 

p. 

47878103 Katz, A. (2009) Raw Analytical Data - Field Notes for Georgia Field Volatility Study: 

Volatility and Air Concentrations of Furfural Following Applications of Multiguard 

Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in 

Georgia: Supplement to MRID 47569101. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 69 p. 

47878104 Katz, A. (2009) Raw Analytical Data - Field Notes for Georgia Field Volatility Study: 

Volatility and Air Concentrations of Furfural Following Applications of Multiguard 

Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in 

Georgia: Supplement to MRID 47569101. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 57 p. 

47878105 Katz, A. (2009) Raw Analytical Data - Field Notes for Georgia Field Volatility Study: 

Volatility and Air Concentrations of Furfural Following Applications of Multiguard 

Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in 

Georgia: Supplement to MRID 47569101. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 56 p. 

47878106 Katz, A. (2009) Raw Analytical Data - Field Notes for Georgia Field Volatility Study: 

Volatility and Air Concentrations of Furfural Following Applications of Multiguard 

Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in 

Georgia: Supplement to MRID 47569101. Project Number: 13782/6128A. 

Unpublished study prepared by Springborn Smithers Laboratories. 63 p. 

47894501 Katz, A. (2009) Supplement to MRID 47701202: Volatility and Air Concentrations of 

Furfural Following Applications of Multiguard Protect to Bare Ground and Turf Grass 

in California. Project Number: 13782/6128A, 1005707A/E. Unpublished study 

prepared by Springborn Smithers Laboratories. 202 p. 

47894601 Katz, A. (2009) Raw Analytical Data-Field Notes for Georgia Field Volatility Study: 

Valatility and Air Concentrations of Furfural Following Applications of Multiguard 

Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in 

Georgia. Project Number: 13782/6128A, 07/37, 13782/6128A/GA. Unpublished study 

prepared by Springborn Smithers Laboratories. 120 p. 

47894602 Katz, A. (2009) Raw Analytical Data-Field Notes for Georgia Field Volatility Study: 

Volatility and Air Concentration of Furfural Applications of Multiguard Protect [90% 

Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in Georgia. Project 

Number: 13782/6128A. Unpublished study prepared by Springborn Smithers 

Laboratories. 100 p. 

47894801 Katz, A. (2009) Addendum to Volatility and Air Concentrations of Furfural Following 

Applications to Multigard Protect [90% Furfural Active Ingredient (a.i)] to Bare Ground 

and Turf Grass in Georgia: Final Report. Unpublished study prepared by Sullivan 

Environmental Consulting, Inc. 27 p. 

47905001 Katz, A. (2009) Raw Analytical Data - Field Notes for Georgia Field Volatility Study: 

Volatility and Air Concentrations of Furfural Following Applications of Multiguard 

Protect [90% Furfural Active Ingredient (a.i.)] to Bare Ground and Turf Grass in 

Georgia: Supplement. Project Number: 13782/6128A. Unpublished study prepared by 

Springborn Smithers Laboratories. 10 p. 
56 

48252901 Sullivan, D. (2010) Monitoring of Flux from the Surface Spray Application of 

Multiguard Protect EC (90% Furfural as Active Ingredient) on Established Turf in Fort 

Pierce, Florida: Final Report. Project Number: SEC2010B, KP/2010/04. Unpublished 

study prepared by Sullivan Environmental Consulting and JRF America and University 

of California. 196 p. 

48708401 Sullivan, D.; Ajwa, H.; Sullivan, R.; et al. (2011) Monitoring of Flux from Soil Injection / 

Rotovation Application Method of Multiguard Protect (90% Furfural as Active 

Ingredient) on Bare Ground Applications in Florida. Project Number: AU/2011/09, 

SEC2011A. Unpublished study prepared by Sullivan Environmental Consulting, JRF 

America and Mirusso Enterprises, Inc. 368p. 

Non-Guideline 

MRID Citation Reference 

 

47253701 Wilson, T. (2007) Detection of Furfural (Multiguard Protect) in Greenhouse Air Using 

Low Volume Air Sampling with Sorbent Trapping and Chemical Analysis. Project 

Number: 62216. Unpublished study prepared by ABC Laboratories, Inc. 151 p. 

47253702 Wilson, T. (2007) Method Validation of Furfural Capture and Analysis in Greenhouse 

Air Using Low Volume Air Sampling, Sorbent Trapping, and HPLC Analysis. Project 

Number: 50536. Unpublished study prepared by ABC Laboratories, Inc. 127 p. 

48252901 Monitoring of Flux from Surface application of Multiguard Protect to established turf 

in Fort Pierce Florida 

Eco Effects Bibliography 

850.2100 71-1 Avian Single Dose Oral Toxicity 

MRID Citation Reference 

4703530

2 

Gallagher, S.; Beavers, J. (2007) Furfural: An Acute Oral Toxicity Study with the Northern 

Bobwhite. Project Number: 566/101, 18755, 050401/5H. Unpublished study prepared by 

Wildlife International Ltd. 55 p. 

4634300

3 

Kumar, A. (2004) Acute Oral Toxicity (LD50) Study of Furfural in Japanese Quail. Project 

Number: 4604. Unpublished study prepared by Jai Research Foundation. 48 p. 

4634300

4 

Kumar, A. (2004) Acute Oral Toxicity (LD50) Study of Furfural in Mallard Ducks. Project 

Number: 4605. Unpublished study prepared by Jai Research Foundation. 46 p. 

4905150

1 

Eickhoff, J.; Cowen, N. (2013) Waiver Request for Avian Oral Toxicity in Passerine Species 

Supporting the Outdoor/Non-food Use of Furfural Technical and the End-use Product 

Multiguard Protect EC. Project Number: AGR/2013/1. Unpublished study prepared by 

ToXcel, LLC. 6p. 
57 

850.2200 Avian dietary toxicity test 

MRID Citation Reference 

48120802 Hubbard, P.; Martin, K. ; Beavers, J. (2010) Furfural Technical: A Dietary LC50 Study with 

the Northern Bobwhite. Project Number: 556/105. Unpublished study prepared by Wildlife 

International, Ltd. 93 p. 

850.2300 Avian reproduction test 

MRID Citation Reference 

48708901 Eickhoff, J. (2011) Waiver Request for an Avian Reproduction Study: Multiguard Protect 

EC. Unpublished study prepared by ToXcel, LLC. 13p. 

Avian Inhalation 

MRID Citation Reference 

48120801 Weinberg, J.T. 2010. Acute Inhalation Toxicity Study of Furfural in Northern Bobwhite Quail. 

Unpublished study performed by WIL Research Laboratories, LLC, Ashland, OH. Laboratory 

Study No. WIL- 477006. Study sponsored by Agriguard Company, LLC, Cranford, NJ and 

toXcel, LLC, Gainesville, VA. Study initiated October 5, 2009 and completed April 15,2010. 

850.2300 Avian reproduction test 

MRID Citation Reference 

48708901 Eickhoff, J. (2011) Waiver Request for an Avian Reproduction Study: Multiguard Protect EC. 

Unpublished study prepared by ToXcel, LLC. 13p. 

850.1010 Aquatic invertebrate acute toxicity, test, freshwater 

daphnids 

MRID Citation Reference 

4634300

1 

Desai, Y. (2004) Acute Immobilisation Study of Furfural in Daphnia magna. Project Number: 

4601. Unpublished study prepared by Jai Research Foundation. 49 p. 

850.1025 Oyster acute toxicity test (shell deposition) 
58 

MRID Citation Reference 

46426507 Blankinship, A.; Kendall, T.; Krueger, H. (2004) Furfural: A 96-Hour Shell Deposition Test 

with the Eastern Oyster (Crassostrea virginica): Final Report. Project Number: 566A/104. 

Unpublished study prepared by Wildlife International, Ltd. 54 p. 

850.1035 Mysid acute toxicity test 

MRID Citation Reference 

46426508 Blankinship, A.; Kendall, T.; Krueger, H. (2004) Furfural: A 96-Hour Flow Through Acute 

Toxicity Test with the Saltwater Mysid (Americamysis bahia): Final Report. Project Number: 

566A/102. Unpublished study prepared by Wildlife International, Ltd. 52 p. 

48241501 Blankinship, A.; Kendall, T.; Krueger, H. (2004) Furfural: A 96-Hour Flow-Through Acute 

Toxicity Test with the Saltwater Mysid (Americamysis bahia): Final Report. Project 

Number: 566A/102. Unpublished study prepared by Wildlife International, Ltd. 7 p.

850.1075 Fish acute toxicity test, freshwater and marine 

MRID Citation Reference 

46207301 Palmer, S.; Kendall, T.; Krueger, H. (2004) Furfural: A 96-Hour Flow-Through Acute Toxicity 

Test with the Bluegill (Lepomis macrochirus): Final Report. Project Number: 566A/101, 

566/1002/BLU/96H2/OECD/OPPTS/100P/604. Unpublished study prepared by Wildlife 

International, Ltd. 54 p. 

46343002 Desai, Y. (2004) Acute Toxicity Study of Furfural In Rainbow Trout, Oncorhynchus mykiss. 

Project Number: 4600. Unpublished study prepared by Jai Research Foundation. 44 p. 

46426509 Blankinship, A.; Kendall, T.; Krueger, H. (2004) Furfural: A 96 Hour Flow-Through Acute 

Toxicity Test with the Sheepshead Minnow (Cyprinodon variegatus): Final Report. Project 

Number: 566A/103A. Unpublished study prepared by Wildlife International, Ltd. 53 p. 

48479301 Palmer, S.; Kendall, T.; Krueger, H. (2011) Furfural: A 96-Hour Flow-Through Acute Toxicity 

Test with the Rainbow Trout (Oncorhynchus mykiss): Final Report. Project Number: 

566A/106. Unpublished study prepared by Wildlife International, Ltd. 59 p. 

48591901 Eickhoff, J. (2011) Waiver Request for Fish Acute Toxicity Study on Fathead Minnow: 

Furfural. Unpublished study prepared by Agriguard Company, LLC. 12p. 

48873301 Brougher, D.; Kendall, T.; Gallagher, S. et al. (2012) Furfural: A 96-Hour Flow-through Acute 

Toxicity Test with the Fathead Minnow (Pimephales promelas): Final Report. Project 

Number: 566A/107. Unpublished study prepared by Wildlife International, Ltd. 59p. 

850.1300 Daphnid chronic toxicity test 

MRID Citation Reference 
59 

4703530

1 

Palmer, S.; Kendall, T.; Krueger, H. (2005) Final Report: Furfural: A Flow Through Life Cycle 

Toxicity Test with the Cladoceran (Daphnia Magna). Project Number: 566A/105A. 

Unpublished study prepared by Wildlife International Ltd. 88 p. 

850.1350 Mysid chronic toxicity test 

MRID Citation Reference 

49048801 Claude, M.; Kendall, T.; Gallagher, S.; et al. (2013) Furfural: A Flow-Through Life-Cycle 

Toxicity Test with the Saltwater Mysid (Americamysis bahia). Project Number: 566A/108. 

Unpublished study prepared by Agriguard Company, LLC. 125p. 

850.1400 Fish early-life stage toxicity test 

MRID Citation Reference 

47692201 York, D. (2009) Furfural Technical: Early Life-Stage Toxicity Test with Fathead Minnow 

(Pimephales promelas), Following OPPTS Draft Guidelines 850.1400. Project Number: 

13782/6137, 083005/OPPTS/ELS/FHM. Unpublished study prepared by Springborn 

Smithers Laboratories. 108 p. 

48453001 York, D. (2011) Response to U.S. EPA DER (D363963) for: Furfural Technical - Early LifeStage Toxicity test with Fathead Minnow, (Pimephales promelas): Final Report. Project 

Number: 13782/6137. Unpublished study prepared by Agriguard Company, LLC. 8 p. 

48708902 Eickhoff, J. (2011) Waiver Request for Fish Early Life-Stage (Estuarine/Marine) and Fish 

Life Cycle (Freshater) Studies: Multiguard Protect EC. Unpublished study prepared by 

ToXcel, LLC. 6p. 

49048802 Minderhout, T.; Kendall, T.; Gallagher, S.; et al. (2013) Furfural: An Early Life-Stage Toxicity 

Test with the Sheepshead Minnow (Cyprinodon variegatus). Project Number: 566A/109B. 

Unpublished study prepared by Agriguard Company, LLC. 92p. 

850.1500 Fish life cycle toxicity 

MRID Citation Reference 

48708902 Eickhoff, J. (2011) Waiver Request for Fish Early Life-Stage (Estuarine/Marine) and Fish 

Life Cycle (Freshater) Studies: Multiguard Protect EC. Unpublished study prepared by 

ToXcel, LLC. 6p. 

850.3020 Honey bee acute contact toxicity 
60 

MRID Citation Reference 

47300201 Sindermann, A.; Porch, J.; Krueger, H. (2007) Furfural: Acute Contact Toxicity Study with 

the Honey Bee: Final Report. Project Number: 566/102. Unpublished study prepared by 

Wildlife International, Ltd. 30 p. 

Honey bee Acute Oral Toxicity 

MRID Citation Reference 

46331506 Marvania, T. (2002) Acute Oral Toxicity (LD50) of Furfural to the Honeybee, Apis Mellifera 

L.. Project Number: 3880. Unpublished study prepared by Jai Research Foundation. 28 p. 

850.4100 Terrestrial plant toxicity, Tier 1 (seeding emergence) 

MRID Citation Reference 

47701204 Porch, J.; Krueger, H.; Martin, K. (2009) Furfural: A Toxicity Test to Determine the Effects of 

the Test Substance on Seedling Emergence of Ten Species of Plants: Final Report. Project 

Number: 566/103. Unpublished study prepared by Wildlife International, Ltd. 123 p. 

 
61 

850.4150 Terrestrial plant toxicity, Tier 1 (vegetative vigor) 

MRID Citation Reference 

47720301 Porch, J.; Krueger, H.; Martin, K. (2009) Furfural: A Toxicity Test to Determine the Effects of 

the Test Substance on Vegetative Vigor of Ten Species of Plants: Final Report. Project 

Number: 566/104, 566/121008/VEGVIG10/SUB566. Unpublished study prepared by Wildlife 

International, Ltd. 157 p. 

850.4225 Seedling emergence, Tier II 

MRID Citation Reference 

47701204 Porch, J.; Krueger, H.; Martin, K. (2009) Furfural: A Toxicity Test to Determine the Effects of 

the Test Substance on Seedling Emergence of Ten Species of Plants: Final Report. Project 

Number: 566/103. Unpublished study prepared by Wildlife International, Ltd. 123 p. 

850.4250 Vegetative vigor, Tier II 

MRID Citation Reference 

47720301 Porch, J.; Krueger, H.; Martin, K. (2009) Furfural: A Toxicity Test to Determine the Effects of 

the Test Substance on Vegetative Vigor of Ten Species of Plants: Final Report. Project 

Number: 566/104, 566/121008/VEGVIG10/SUB566. Unpublished study prepared by Wildlife 

International, Ltd. 157 p. 

850.4400 Aquatic plant toxicity test using Lemna spp. Tiers I and II 

MRID Citation Reference 

47569401 Softcheck, K. (2008) Furfural Technical - 7-Day Toxicity Test with Duckweed (Lemna gibba). 

Project Number: 13782/6139. Unpublished study prepared by Springborn Smithers 

Laboratories. 93 p. 

850.4450 Aquatic plants field study, Tier III 

MRID Citation Reference 

47569402 Softcheck, K. (2008) Furfural Technical - 96-Hour Toxicity Test with the Freshwater 

Green Alga, Pseudokirchneriella subcapitata. Project Number: 13782/6133. 

Unpublished study prepared by Springborn Smithers Laboratories. 96 p. 
62 

47569403 Softcheck, K. (2008) Furfural Technical - 96-Hour Toxicity Test with the Marine 

Diatom, Skeletonema costatum. Project Number: 13782/6134. Unpublished study 

prepared by Springborn Smithers Laboratories. 101 p. 

47569404 Softcheck, K. (2008) Furfural Technical - 96-Hour Toxicity Test with the Freshwater 

Diatom, Navicula pelliculosa. Project Number: 13782/6135. Unpublished study 

prepared by Springborn Smithers Laboratories. 102 p. 

47569405 Softcheck, K. (2008) Furfural Technical - 96-Hour Toxicity Test with the Freshwater 

Blue-Green Alga, Anabaena flos-aquae. Project Number: 13782/6136. Unpublished 

study prepared by Springborn Smithers Laboratories. 101 p. 

850.5400 Acute toxicity to Aquatic plants 

MRID Citation Reference 

47569402 Softcheck, K. (2008) Furfural Technical - 96-Hour Toxicity Test with the Freshwater Green 

Alga, Pseudokirchneriella subcapitata. Project Number: 13782/6133. Unpublished study 

prepared by Springborn Smithers Laboratories. 96 p. 

47569403 Softcheck, K. (2008) Furfural Technical - 96-Hour Toxicity Test with the Marine Diatom, 

Skeletonema costatum. Project Number: 13782/6134. Unpublished study prepared by 

Springborn Smithers Laboratories. 101 p 

47569404 Softcheck, K. (2008) Furfural Technical - 96-Hour Toxicity Test with the Fresh-water Diatom, 

Navicula pelliculosa. Project Number: 13782/6135. Unpublished study prepared by 

Springborn Smithers Laboratories. 102 p. 

47569405 Softcheck, K. (2008) Furfural Technical - 96-Hour Toxicity Test with the Fresh-water BlueGreen Alga, Anabaena flos-aquae. Project Number: 13782/6136. Unpublished study 

prepared by Springborn Smithers Laboratories. 101 p. 

850.6200 Earthworm Acute Toxicity 

MRID Citation Reference 

46331506 Desai, N. (2002) Acute Toxicity Study of Furfural To Earthworm. Project Number: 3879. 

Unpublished study prepared by Jai Research Foundation. 21 p. 

Non-Guideline Study 

MRID Citation Reference 

46426503 Gledhill, W. (2004) [14-C]Furfural - Plant Uptake and Translocation Test. Project 

Number: 13782/6111. Unpublished study prepared by Springborn Smithers 

Laboratories. 119 p. 
63 

46426506 Anton, R.; Barlow, S.; Boskou, D.; et. al. (2004) Furfural and Furfural Diethylacetal: 

Opinion of the EFSA Scientific Panel on Food Additives, Flavourings, Processing Aids 

and Materials in Contact with Food. The EFSA Journal 67(2004):1-27. 

47419101 Staal, Y.; Kleinnijenhuis, A.; Junker, K.; et al. (2008) Sub-acute (28-day) Inhalation 

Toxicity Study with Furfural in Rats: Final Report. Project Number: V7649, 031/12219, 

7649. Unpublished study prepared by TNO Voeding. 262 p. 

47270201 Martin, K.; Nixon, W. (2007) Analytical Method Verification for the Determination of 

Furfural in Avian Diet. Project Number: 566C/101, SANCO/3029/99/REV/4. 

Unpublished study prepared by Agriguard Company, LLC. 32 p.