U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Report 2008–5016

Occurrence of Chlorothalonil, Its Transformation 

Products, and Selected Other Pesticides in Texas 

and Oklahoma Streams, 2003–2004

Occurrence of Chlorothalonil, Its 

Transformation Products, and Selected 

Other Pesticides in Texas and Oklahoma 

Streams, 2003–2004

By William A. Battaglin, Kathryn Kuivila, Kim Winton, and Michael Meyer

Scientific Investigations Report 2008–5016

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

DIRK KEMPTHORNE, Secretary

U.S. Geological Survey

Mark D. Myers, Director

U.S. Geological Survey, Reston, Virginia: 2008

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Suggested citation:

Battaglin, W.A., Kuivila, K., Winton, K., and Meyer, M., 2008, Occurrence of chlorothalonil, its transformation products, and selected other pesticides in Texas and Oklahoma streams, 2003–2004: U.S. Geological 

Survey Scientific Investigations Report 2008–5016, 9 p.

About this Product

For more information concerning this publication, contact:

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Or visit the Research on Pesticides in the Environment Web site at:

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Manuscript approved for publication, September 2007

Edited by Mary A. Kidd

Layout by Sharon Powers
iii

Contents

Abstract ..........................................................................................................................................................1

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

Chlorothalonil Use and Toxicity ..........................................................................................................1

Sampling Sites and Sample Collection .............................................................................................2

Analytical Methods...............................................................................................................................5

Occurrence of Chlorothalonil, Its Transformation Products, and Selected Other Pesticides..........5

Summary..........................................................................................................................................................8

Acknowledgments.........................................................................................................................................8

References Cited............................................................................................................................................8

Figures

1. Sampling-site locations, drainage basins, and acres of peanuts harvested, 2002 ...........3

2. Sampling-site locations, drainage basins, and estimated annual chlorothalonil 

use, circa 2002...............................................................................................................................4

Tables

1. Sampling-site names, site ids, drainage areas, acres of harvested peanuts 

(2002), and estimated chlorothalonil application (circa 2002)...............................................5

2. Range of measured pesticide concentrations in micrograms per liter, by 

site, for stream samples collected in Texas and Oklahoma in 2003 and 2004 ....................7
iv

Conversion Factors

SI to Inch/Pound

Multiply By To obtain

Length

meter (m) 3.281 foot (ft) 

kilometer (km) 0.6214 mile (mi)

Area

square meter (m2

) 0.0002471 acre 

square kilometer (km2

) 247.1 acre

square kilometer (km2

) 0.3861 square mile (mi2)

Volume

liter (L) 0.2642 gallon (gal)

cubic meter (m3

) 264.2 gallon (gal) 

Flow rate

cubic meter per second (m3

/s) 35.31 cubic foot per second (ft3

/s)

Mass

gram (g) 0.03527 ounce (oz)

kilogram (kg) 2.205 pound (lb)

metric ton (mt) 1.102 ton, short (2,000 lb)

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as follows:

 °F=(1.8×°C)+32

Vertical coordinate information is referenced to the North American Vertical Datum of 1988 

(NAVD 88).

Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).

Altitude, as used in this report, refers to distance above the vertical datum.
Abstract 

The primary purpose of the study described in this report 

was to determine if the fungicide chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile), three of its transformation products, 

or selected other pesticides are transported to surface water 

after use on peanuts or other crops in Texas and Oklahoma. 

The results summarized here are part of a larger study that 

includes data from sites in Alabama, Florida, and Georgia. 

Chlorothalonil is classified as a probable carcinogen, and the 

4-hydroxy of chlorothalonil transformation product is more 

soluble, more stable, and, for some species, more toxic than its 

parent compound. In 2003, water samples were collected from 

three surface-water sites in Texas and two surface-water sites 

in Oklahoma; in 2004, samples were collected from the two 

Oklahoma sites. Chlorothalonil was not detected in any of the 

20 samples analyzed. The 4-hydroxy of chlorothalonil transformation product was detected in three samples collected in 

2004, with a maximum concentration of 0.018 microgram per 

liter (μg/L); the other two transformation products (diamide 

chlorothalonil and 1-amide-4-hydroxy chlorothalonil) were 

not detected in any sample. In addition, 19 samples were 

analyzed for as many as 109 other pesticides and transformation products. Atrazine was detected in 13 samples and had a 

maximum concentration of 0.122 μg/L. Deethylatrazine was 

detected in 10 samples and had a maximum concentration of 

0.04 μg/L. Metolachlor was detected in eight samples and had 

a maximum concentration of 0.019 μg/L. Fifteen other pesticides or pesticide transformation products also were detected. 

In general, concentrations of pesticides were less than concentrations that are commonly observed in Midwestern streams. 

The results indicate that the use of chlorothalonil on peanut 

crops has not resulted in substantial contamination of the studied streams in Texas and Oklahoma.

Introduction

In 2003 and 2004, the U.S. Geological Survey (USGS) 

conducted a study to determine if the fungicide chlorothalonil 

(2,4,5,6-tetrachloroisophthalonitrile) or three of its transformation products are transported to surface water after use on 

peanuts or other crops in five southern States (Scribner and 

others, 2006). Chlorothalonil has a wide variety of beneficial 

uses, including agricultural, home and garden, industrial, and 

vector control of fungi, and it is used extensively for disease 

control in peanuts, potatoes, turf, and many fruit and vegetable 

crops. 

The purpose of this report is to summarize occurrence of 

chlorothalonil, its transformation products, and selected other 

pesticides in four Texas and Oklahoma streams. Three pairs 

of samples are used to compare nonstorm and storm-event 

pesticide flux. Data used in this report are available in Scribner 

and others (2006). Peanuts are the primary crop treated with 

chlorothalonil in Texas and Oklahoma, but it is also applied to 

onions, melons, cabbage, and other crops (National Agricultural Statistics Service, 2007).

Soybean rust is a devastating plant disease caused by 

fungal pathogens. Soybean rust was detected for the first time 

in the United States in November 2004, in Louisiana. In 2007, 

soybean rust was confirmed on soybean crops in 24 counties 

in Texas and 8 in Oklahoma (U.S. Department of Agriculture, 

2007a). The use of fungicides on soybeans is expected to 

increase in areas where soybean rust spreads during the growing season, and chlorothalonil is one of only a few fungicides 

registered for use as a treatment of soybean rust. Hence, 

selected results from this study will provide a baseline of 

water-quality information collected prior to the use of fungicides to control soybean rust.

Chlorothalonil Use and Toxicity

Chlorothalonil is a broad spectrum, nonsystemic fungicide used to prevent foliar diseases on vegetable, field, and 

ornamental crops (Meisterpro, 2007). Chlorothalonil is used in 

agricultural, home and garden, and industrial settings, primarily on peanuts, potatoes, fruit, and turf. Chlorothalonil was 

first registered for use on food crops in the United States in 

1970 and is historically one of the most heavily used fungicides with U.S. applications estimated at 5,245 metric tons 

Occurrence of Chlorothalonil, Its Transformation Products, 

and Selected Other Pesticides in Texas and Oklahoma 

Streams, 2003–2004

By William A. Battaglin, Kathryn Kuivila, Kim Winton, and Michael Meyer
2 Occurrence of Chlorothalonil, Its Transformation Products, and Other Pesticides in Texas and Oklahoma Streams

per year (mt/yr) in 1992, 5,404 mt/yr in 1997, and 3,936 mt/

yr in 2002 (Gianessi and Reigner, 2006). In 2002, the estimated use of chlorothalonil on peanuts in Texas was 50.0 mt, 

and the total use on all agricultural products was 85.4 mt. In 

Oklahoma the estimated use of chlorothalonil on peanuts was 

10.3 mt, whereas the total use on all agricultural products 

was 18.8 mt (Gianessi and Reigner, 2006). Acres of harvested 

peanuts in 2002 (U.S. Department of Agriculture, 2007b) and 

the estimated annual application of chlorothalonil circa 2002 

(Gianessi and Reigner, 2006) are shown in figures 1 and 2. 

Chlorothalonil has the potential to contaminate water 

bodies adjacent to its point of use by spray drift, runoff, or sediment transport. Chlorothalonil previously has been detected in 

surface water (Scott and others, 2002; Wauchope and others, 

2004), rainfall (Sakai, 2002), and air samples (McConnell and 

others, 1998) generally adjacent to agricultural areas where 

it was applied. The U.S. Environmental Protection Agency 

classifies chlorothalonil as a probable carcinogen with very 

high toxicity to fish and aquatic invertebrates (U.S. Environmental Protection Agency, 1999) but low toxicity to birds and 

mammals. Chlorothalonil has three primary transformation 

products (TPs): 4-hydroxy chlorothalonil, diamide chlorothalonil, and 1-amide-4-hydroxy chlorothalonil. Chlorothalonil 

is resistant to degradation by hydrolysis, volatilization, and 

microbial activity but may adsorb to sediments. Chlorothalonil 

TPs may be more persistent and mobile than chlorothalonil. 

The 4-hydroxy chlorothalonil TP is more toxic to birds but 

less toxic to fish and aquatic invertebrates than chlorothalonil 

(U.S. Environmental Protection Agency, 1999). 

Sampling Sites and Sample Collection

Sampling sites (fig. 1, table 1) were selected on the basis 

of estimates of harvested peanut acreage (fig. 1), chlorothalonil use (fig. 2), watershed area, availability of streamflow 

data, and personnel safety. The five sites sampled on four 

streams in Texas and Oklahoma were part of a larger study by 

the USGS that included sites in Alabama, Georgia, and Florida 

(Scribner and others, 2006). 

In general, samples were collected after the application 

of chlorothalonil on local peanut crops. Peanuts crops may be 

treated with chlorothalonil several times during the growing 

season. In several cases, samples were collected during or 

just after rainfall of sufficient intensity to produce runoff and 

a large increase in streamflow. Samples were collected using 

standardized protocols (Wilde and others, 1999) by wading 

or from bridges using the equal-width-increment method 

(Shelton, 1994). A complete description of sample-collection 

and quality-assurance protocols used for this study is provided 

in Scribner and others (2006). Site 1 was sampled three times 

Peanut field near Eakly, Oklahoma (photograph by W. A. Battaglin).
Introduction 3

1

2

3

4

5

5

N

OKLAHOMA

TEXAS

EXPLANATION

Acres of peanuts harvested, 2002

None reported

Amount not disclosed

1 to 100

101 to 1,000

1,001 to 5,000

5,001 to 10,000

More than 10,000

Sampling site and drainage basin (table 1)

Base from U.S. Geological Survey Data from U.S. Department of Agriculture, 2007b

digital data, 1:2,000,000, 1972

Albers Equal-Area Conic projection

with standard parallels and central meridian

Figure 1. Sampling-site locations, drainage basins, and acres of peanuts harvested, 2002.
4 Occurrence of Chlorothalonil, Its Transformation Products, and Other Pesticides in Texas and Oklahoma Streams

1

2

3

4

5

5

N

OKLAHOMA

TEXAS

EXPLANATION

Kilograms of chlorothalonil

applied, circa 2002

None reported

1 to 100

101 to 500

501 to 1,000

1,001 to 5,000

More than 5,000

Sampling site and drainage basin (table 1)

Base from U.S. Geological Survey Data modified from Gianessi and Reigner, 2006

digital data, 1:2,000,000, 1972

Albers Equal-Area Conic projection

with standard parallels and central meridian

Figure 2. Sampling-site locations, drainage basins, and estimated annual chlorothalonil use, circa 2002.
Occurrence of Chlorothalonil, Its Transformation Products, and Selected Other Pesticides 5

in 2003 and three times in 2004. Site 2 was sampled two 

times in 2003 and three times in 2004. Sites 3, 4, and 5 were 

each sampled three times in 2003 but were not sampled in 

2004. Daily mean streamflow values used for the calculation 

of pesticide fluxes are from the USGS National Water 

Information System (NWIS) (2008).

A geographic information system (GIS) was used to 

manage the county-level information on crops and pesticide 

use for this study. The total use of chlorothalonil on all crops 

by county was calculated from data provided in Gianessi and 

Reigner (2006). An area-weighted sum algorithm programmed 

in the GIS (Battaglin and Goolsby, 1998) was used to estimate 

the amounts of pesticides used or areas of crops harvested 

within drainage basins associated with the sampling sites 

(table 1). The algorithm accounts for cases where an entire 

county is within a single drainage basin and where only a portion of a county is within a drainage basin.

Analytical Methods

Twenty samples were analyzed for chlorothalonil, three 

chlorothalonil TPs. Nineteen of those samples also were analyzed for as many as 109 other pesticides or pesticide TPs. The 

exception was the July 14, 2003, sample from site 3, which 

only was analyzed for chlorothalonil and its three TPs. Chlorothalonil and its TPs were analyzed at the USGS Organic 

Geochemistry Research Laboratory in Lawrence, Kansas. The 

method utilizes solid-phase extraction, liquid chromatography/

mass spectrometry, and atmospheric pressure chemical ionization or electrospray ionization (Scribner and others, 2006). 

The other 109 pesticides and TPs were analyzed at the USGS 

National Water Quality Laboratory in Denver, Colorado, using 

methods described by Zaugg and others (1995), Furlong and 

others (2001), and Madsen and others (2003).

Quality-assurance (QA) samples collected for this study 

included field blanks and spikes and field replicates. Results 

for QA samples collected at Texas and Oklahoma sites are 

summarized here. Chlorothalonil and its TPs were not detected 

in any of the four blank samples, and concentrations in four 

pairs of field replicate and environmental samples were all 

less than the laboratory reporting level (0.050 μg/L). Percent 

recoveries of four field-spike samples ranged from 44 to 

76 percent. Scribner and others (2006) provide a complete 

discussion of QA sample results for this study. 

Occurrence of Chlorothalonil, Its 

Transformation Products, and Selected 

Other Pesticides

Chlorothalonil, 1-amide-4-hydroxy chlorothalonil, and 

diamide chlorothalonil were not detected in any of the 20 

samples, but 4-hydroxy chlorothalonil was detected at both 

sites in Oklahoma (table 2). The drainage areas for these two 

sites include portions of counties with higher levels of chlorothalonil use than do the other three sites (fig. 2), and Cobb 

Creek at Fort Cobb, Oklahoma, has the most acres and the 

highest percentage of the watershed in peanuts of the five sites 

(table 1).

Atrazine, deethylatrazine, and metolachlor were each 

detected at four of the five sites (table 2). Atrazine was 

detected in 13 of 19 analyzed samples and had a maximum 

concentration of 0.122 μg/L. Deethylatrazine was detected in 

10 of 19 analyzed samples and had a maximum concentration 

of 0.04 μg/L. Metolachlor was detected in 8 of 19 analyzed 

samples and had a maximum concentration of 0.019 μg/L. 

Atrazine is a herbicide used on corn crops; metolachlor 

is a herbicide used on peanuts, cotton, and corn; and 

deethylatrazine is an atrazine TP. Tebuthiuron was detected 

at one site in Oklahoma and one site in Texas. Tebuthiuron 

is a herbicide used on rangeland and noncropland. Fourteen 

Table 1. Sampling-site names, site ids, drainage areas, acres of harvested peanuts (2002), and estimated 

chlorothalonil application (circa 2002). 

[id, identification; km2, square kilometers; %, percent; USGS, U.S. Geological Survey]

Site id 

(number 

in figs. 

1 and 2)

Site name Drainage 

area (km2

)

USGS gaging 

station id 

number

Acres of harvested 

peanuts (percentage 

of drainage area)

Chlorothalonil 

applications 

(kilograms active 

ingredient)

Oklahoma

1 Cobb Creek near Eakly, OK 342 07325800 480 (0.57%) 101

2 Cobb Creek near Fort Cobb, OK 795 07326000 4,900 (2.49%) 862

Texas

3 Beaver Creek near Electra, TX 1,689 07312200 1,550 (0.37%) 314

4 Sabana River near DeLeon, TX 684 08099300 1,740 (1.03%) 424

5 San Miguel Creek near Tilden, TX 2,028 08206700 3,640 (0.72%) 967
6 Occurrence of Chlorothalonil, Its Transformation Products, and Other Pesticides in Texas and Oklahoma Streams

Cobb Creek near Eakly, Oklahoma (photograph by W.A. Battaglin).

other pesticides or pesticide TPs (2,4-D, bentazon, carbaryl, 

deisopropylatrazine, hydroxyatrazine, 2-hydroxyatrazine, 

malathion, oryzalin, pendimethalin, prometon, propargite, 

simazine, terbacil, and triclopyr) were detected in four or 

fewer samples. The concentration of carbaryl exceeded the 

freshwater aquatic-life standard (Environment Canada, 2007) 

of 0.2 μg/L in one sample from San Miguel Creek in Texas. 

No other pesticide or pesticide TP exceeded its freshwater 

aquatic-life standard, but such standards are available for only 

8 of the 22 compounds listed in table 2.

Caffeine was detected in samples from the two sites in 

Oklahoma at concentrations ranging from 0.020 to 0.037 μg/L. 

Caffeine was not analyzed for in samples from the sites in 

Texas. Caffeine is not a traditional pesticide and is most 

likely coming from human sources such as treated wastewater 

discharge or individual sewage disposal system wastes from 

within the watershed.

Storm-event or runoff-event samples are water samples 

that are collected after local rainfall that has resulted in a 

substantial increase in streamflow at the study site. Previous 

studies indicated that concentrations and resulting fluxes 

of pesticides commonly are elevated during such events 

(Thurman and others, 1991; Battaglin and others, 2005). 

For this report, daily pesticide fluxes in grams per day (g/d) 
Occurrence of Chlorothalonil, Its Transformation Products, and Selected Other Pesticides 7

Table 2. Range of measured pesticide concentrations in micrograms per liter, by site, for stream samples collected in Texas and 

Oklahoma in 2003 and 2004. 

[E, estimated concentration; ND, not detected; NA, not analyzed; TP, transformation product]

Pesticide Action Cobb Creek near 

Eakly, Oklahoma

Cobb Creek near 

Fort Cobb, 

Oklahoma

Beaver 

Creek near 

Electra, 

Texas 

Sabana River near 

DeLeon, Texas 

San Miguel Creek 

near Tilden, Texas 

Chlorothalonil Fungicide ND ND ND ND ND

4-hydroxychlorothalonilFungicide 

TP 0.002 – 0.018 0.002 ND ND ND

1-amide-4-

hydroxy 

chlorothalonil

Fungicide 

TP ND ND ND ND ND

Diamide 

chlorothalonil

Fungicide 

TP ND ND ND ND ND

2,4-D Herbicide 0.037 E 0.038 NA NA NA

Atrazine Herbicide E 0.006 – 0.018 0.012 – 0.043 0.024 ND 0.008 – 0.122

Bentazon Herbicide E 0.007 ND NA NA NA

Carbaryl Insecticide ND ND ND ND E 0.27

Deethylatrazine Herbicide 

TP 0.006 – 0.009 0.012 0.006 ND 0.040

DeisopropylatrazineHerbicide 

TP ND E 0.007 NA NA NA

HydroxyatrazineHerbicide 

TP 0.025 0.028 – 0.038 NA NA NA

2-hydroxyatrazineHerbicide 

TP E 0.025 E 0.028– E 0.038 NA NA NA

Malathion Insecticide ND ND 0.033 ND ND

Metolachlor Herbicide E 0.001 – 

E 0.008 E 0.004 ND E 0.010 – 0.019 E 0.007 – 0.019

Oryzalin Herbicide ND 0.043 – 0.127 NA NA NA

Pendimethalin Herbicide 0.040 ND ND ND ND

Prometon Herbicide ND E 0.004 ND ND ND

Propargite Insecticide ND 0.007 – 0.008 ND ND ND

Simazine Herbicide ND E 0.007 – 

E 0.008 ND ND ND

Tebuthiuron Herbicide E 0.004 – 0.090 ND ND ND 0.008

Terbacil Herbicide E 0.008 ND ND ND ND

Triclopyr Herbicide E 0.245 ND NA NA NA
8 Occurrence of Chlorothalonil, Its Transformation Products, and Other Pesticides in Texas and Oklahoma Streams

were estimated by multiplying the daily mean streamflow 

on the date of sample collection by the sum of the pesticide 

concentrations (in μg/L) from each sample and a conversion 

factor. The actual daily pesticide flux is likely different 

from the estimates reported here because not all pesticides 

that could be present are analyzed for; also, during a day, 

both streamflow and pesticide concentrations can change 

considerably. 

Three pairs of samples from this study can be used to 

compare nonstorm with storm-event pesticide flux. At Cobb 

Creek near Eakly, Oklahoma (site 1), two samples collected 13 

days apart in August 2004 had daily mean streamflows of 0.28 

and 3.20 cubic meters per second (m3

/s), respectively (Scribner and others, 2006), and streamflow on the day before the 

second sample was collected was 0.20 m3

/s (USGS National 

Water Information System, 2008). Four pesticides or pesticide 

TPs were detected in the first sample, and six pesticides or 

pesticide TPs were detected in the second sample. The daily 

flux of measured pesticides was 6.6 grams per day (g/d) in 

the first sample and 85.7 g/d in the second sample. At Beaver 

Creek near Electra, Texas (site 3), two samples that were collected 43 days apart in July and August 2003 had daily mean 

streamflows of 0.16 and 3.11 m3

/s, respectively, and streamflow on the day before the second sample was collected was 

0.01 m3

/s. One pesticide was detected in the first sample and 

two pesticides were detected in the second sample. The daily 

flux of measured pesticides was 0.33 g/d in the first sample 

and 15.3 g/d in the second sample. At San Miguel Creek near 

Tilden, Texas (site 5), two samples that were collected 2 days 

apart in July 2003 had daily mean streamflows of 4.70 and 

23.0 m3

/s, respectively, and streamflow on the day before the 

second sample was collected was 31.1 m3

/s. Three pesticides 

or pesticide TPs were detected in each sample, and the daily 

flux of measured pesticides was 68.6 g/d in the first sample 

and 85.4 g/d in the second sample. These results confirm that 

the studied streams transported much larger quantities of pesticides after rainfall and during subsequent runoff events than 

they did during nonstorm conditions.

In general, the concentrations of pesticides observed in 

Texas or Oklahoma streams were less than those commonly 

observed in streams in the Midwestern United States (Battaglin and others, 2005). These results indicate that the use of 

chlorothalonil on peanut crops has not resulted in contamination of the studied streams in Texas and Oklahoma. This could 

in part be due to lower rainfall and subsequent runoff in this 

generally dry region. Chlorothalonil was detected in 4 of the 

93 samples collected Alabama, Florida, and Georgia (Scribner and others, 2006), and 4-hydroxy of chlorothalonil was 

detected in 23 of those 93 samples. Additional data need to be 

collected in order to determine if the use of chlorothalonil or 

other fungicides on soybean crops to control soybean rust will 

result in contamination of surface water by those chemicals. 

One other fungicide (propiconazole) that is currently (2007) 

approved for emergency treatment of soybean rust (U.S. Environmental Protection Agency, 2007) was analyzed for in this 

study but was not detected in any sample. 

Summary

This report summarizes the occurrence of the fungicide chlorothalonil, three of its transformation products, and 

selected other pesticides in four Texas and Oklahoma streams. 

The results reported on here are part of a larger study that 

includes data from streams in Alabama, Florida, and Georgia. 

Chlorothalonil is classified as a probable carcinogen, and the 

4-hydroxy of chlorothalonil transformation product is more 

soluble, more stable, and, for some species, more toxic than 

its parent compound. Chlorothalonil, 1-amide-4-hydroxy 

chlorothalonil, and diamide chlorothalonil were not detected 

in any of the 20 samples from Texas and Oklahoma, but low 

concentrations of 4-hydroxy chlorothalonil were detected in 

three samples from two sites in Oklahoma, indicating that 

chlorothalonil use on peanuts or other crops has not resulted 

in substantial contamination of the water in the studied 

streams. Eighteen other pesticides or transformation products 

were detected in one or more of the samples, but generally at 

concentrations that were less than those observed in streams in 

the Midwestern United States. The studied streams transported 

much larger quantities of pesticides after rainfall and during 

subsequent runoff events than they did during nonstorm 

conditions. 

Acknowledgments

The authors thank USGS employees in the Texas and 

Oklahoma USGS Water Science Centers for collecting water 

samples and providing other technical support for this project. 

This research was supported by the U.S. Geological Survey 

Toxic Substances Hydrology Program. For more information 

see http:/toxics.usgs.gov/. This report benefited from reviews 

by S. Jerrod Smith, Juliane B. Brown, Betty Palcsak, Mary 

Kidd, and Keith Lucey.

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