Department of Pesticide Regulation

 

Paul E. Helliker

Director M E M O R A N D U M

Gray Davis

Governor

Winston H. Hickox

Secretary, California

Environmental

Protection Agency

1001 I Street • P.O. Box 4015 • Sacramento, California 95812-4015 • www.cdpr.ca.gov

A Department of the California Environmental Protection Agency

TO: John S. Sanders, Ph.D., Chief

Environmental Monitoring Branch

FROM: Frank Spurlock, Ph.D.

Senior Environmental Research Scientist

(916) 324-4124

DATE: November 8, 2002

SUBJECT: PESTICIDE VOLATILE ORGANIC COMPOUND EMISSIONS INVENTORY 

2002 UPDATE: ESTIMATED EMISSIONS JANUARY – DECEMBER 2001

I. OVERVIEW

This memorandum summarizes the Department of Pesticide Regulation’s (DPR’s) 2001 

estimated potential pesticide volatile organic compound (VOC) emission data. An electronic file 

containing detailed statewide 2001 data is available by download from DPR’s internet webpage 

(http://www.cdpr.ca.gov/docs/pur/vocproj/vocmenu.htm) along with the VOC data file 

dictionary, VOC emissions data from previous years, and various VOC documentation. 

The data processing and calculation procedures for the 2001 inventory were essentially identical 

to those developed for the recent revision of the 1990 – 2000 inventories (Spurlock, 2002a), and 

these calculation procedures are now available in a detailed report (Spurlock, 2002b). Briefly, 

VOC emission estimates were obtained by combining 2001 agricultural and commercial 

structural pesticide use data with product-specific emission potentials. The 2001 VOC emissions 

reported here are based on DPR’s preliminary 2001 pesticide use data, released in October 2002 

(DPR, 2002).

II. VOC INVENTORY RESULTS BY NON-ATTAINMENT AREA (NAA)

A. NAA 1, Sacramento Metropolitan Area

The 2001 VOC emissions in NAA 1 were lower than any previous year at approximately 

1.26 million pounds of total organic gases (TOG) (Figure 1). As a result, 2001 emissions 

were below the 2005 goal of 1.54 million pounds TOG for the first time. The monthly 

distribution of NAA 1 VOC emissions is shown in Figure 2.

 Approximately 90 percent of VOC emissions in NAA 1 were attributable to agricultural 

pesticide use as compared to 10 percent from commercial structural pesticide applications. 

Similar to most other areas of California the largest contributors to VOC emissions were 

fumigants; products containing the three top fumigants metam-sodium, methyl bromide, and 

1,3-dichloropropene accounted for approximately 27 percent of 2001 NAA 1 VOC emissions 
John S. Sanders, Ph.D.

November 8, 2002

Page 2

(Table 1). Another significant contributor to NAA 1 potential emissions was the rice 

herbicide molinate as in previous years. 

TABLE 1. Top ten “primary active ingredients” contributing to 2001 VOC emissions in NAA 1, 

the Sacramento Metropolitan Area, listed in descending order of total emissions of products 

containing the primary active ingredient. Here the primary active ingredient is defined as the 

pesticidal active ingredient present at the highest percentage in a product. This approach 

prevents “double-counting” of emissions from products containing two active ingredients. 

Primary AI

Total product emissions 

(lbs)

% of all 2001 pesticide 

emissions in NAA1

METAM-SODIUM 240284 19.1%

MOLINATE 188200 15.0%

METHYL BROMIDE 75970 6.1%

CHLORPYRIFOS 65618 5.2%

CYPERMETHRIN 55841 4.4%

TRIFLURALIN 53879 4.3%

THIOBENCARB 37495 3.0%

2,4-D, DIMETHYLAMINE 

SALT 33987 2.7%

OXYFLUORFEN 27395 2.2%

GLYPHOSATE, 

ISOPROPYLAMINE SALT 27141 2.2%

B. NAA 2, San Joaquin Valley

VOC emissions in NAA 2 continued to decline in 2001, following a trend that started in 1995 

(Figure 1). The 2001 NAA 2 VOC emissions of 13.9 million lbs TOG were 26% lower than 

in 2000, and approximately 2.7 million lbs less than the NAA 2 2005 target of 16.6 million 

lbs. The monthly distribution of NAA 2 emissions is shown in Figure 2.

Approximately 98 percent of 2001 NAA 2 VOC emissions were attributable to agricultural 

pesticide uses with the remaining 2 percent resulting from commercial structural pesticide 

applications. Similar to previous years, the principal contributors to NAA 2 emissions were 

fumigants; more than 52 percent of VOC emissions were attributable to products in which 

metam-sodium, methyl bromide, or 1,3-dichloropropene were the primary active ingredient 

(Table 2). 
John S. Sanders, Ph.D.

November 8, 2002

Page 3

Some 2001 Kern County pesticide use data was not submitted to DPR due to data processing 

problems at the county (Department of Pesticide Regulation, 2002). Based on pesticide use in 

surrounding San Joaquin Valley Counties in 2000 and 2001, an estimate of Kern County’s 

actual 2001 reported pesticide use is about 1 – 2 million pounds greater than the reported use. 

The net effect on 2001 NAA 2 VOC emission estimates reported here is that they may be low 

approximately 120,000 – 250,000 pounds too low. 

TABLE 2. Top ten “primary active ingredients” contributing to 2000 VOC emissions in NAA 2, 

the San Joaquin Valley, listed in descending order of total emissions of products containing the 

primary active ingredient. Here the primary active ingredient is defined as the pesticidal active 

ingredient present at the highest percentage in a product. This approach prevents “doublecounting” of emissions from products containing two active ingredients. 

Primary AI

Total product emissions 

(lbs)

% of all 2001 pesticide 

emissions in NAA2

METAM-SODIUM 3317115 23.8%

1,3-DICHLOROPROPENE 2762938 19.8%

METHYL BROMIDE 1171962 8.4%

CHLORPYRIFOS 1089846 7.8%

OXYFLUORFEN 451556 3.2%

GLYPHOSATE, 

ISOPROPYLAMINE SALT 396863 2.8%

TRIFLURALIN 362615 2.6%

PENDIMETHALIN 324062 2.3%

ACROLEIN 194668 1.4%

SULFUR 162336 1.2%

C. NAA 3, Southeast Desert

While VOC emissions in NAA 3 increased significantly between the early 1990s through 

2000, 2001 emissions were less than those in either 1999 or 2000 (Figure 1). However, the 

estimated 2001 NAA 3 emissions of 1.43 million pounds remained approximately 85% (0.66 

million lbs) greater than the 2005 NAA 3 target of 0.77 million lbs. The monthly distribution 

of NAA 3 emissions is shown in Figure 2.

 Approximately 96 percent of 2001 NAA 3 VOC emissions were attributable to agricultural 

uses, with the remaining 4 percent a result of commercial structural pesticide applications. 

Emissions in NAA 3 are driven almost entirely by fumigants; almost 83 percent of 2001 
John S. Sanders, Ph.D.

November 8, 2002

Page 4

NAA 3 emissions were attributable to products in which metam-sodium, methyl bromide, or 

1,3-dichloropropene was the primary active ingredient (Table 3). 

TABLE 3. Top ten “primary active ingredients” contributing to 2000 VOC emissions in NAA 3, 

the Southeast Desert, listed in descending order of total emissions of products containing the 

primary active ingredient. Here the primary active ingredient is defined as the pesticidal active 

ingredient present at the highest percentage in a product. This approach prevents “doublecounting” of emissions from products containing two active ingredients. 

Primary AI

Total product emissions 

(lbs)

% of all 2001 pesticide 

emissions in NAA3

METAM-SODIUM 858256 60.2%

METHYL BROMIDE 238242 16.7%

1,3-DICHLOROPROPENE 82623 5.8%

GIBBERELLINS 27166 1.9%

HYDROGEN CYANAMIDE 16835 1.2%

CHLOROPICRIN 16341 1.1%

CHLORPYRIFOS 16282 1.1%

GLYPHOSATE, 

ISOPROPYLAMINE SALT 15364 1.1%

TRIFLURALIN 12847 0.9%

DIAZINON 12082 0.8%

D. NAA 4, Ventura

In 2001, VOC emissions in NAA 4, Ventura, showed a decrease for the second consecutive 

year. However, the 2001 emissions of 2.90 million lbs were still much higher than estimated 

emissions in the early 1990’s, and were approximately 70% greater than the 2005 target of 

1.71 million lbs (Figure 1). Nearly 100% of potential 2001 NAA 4 emissions resulted from 

agricultural pesticide uses, with commercial structural pesticide applications accounting for 

only 0.3 percent of emissions. The monthly distribution of NAA 4 emissions is shown in 

Figure 2.

Similar to 2000, 2001 NAA 4 VOC emissions were dominated by fumigants; 88 percent of 

total emissions were attributable to products in which metam-sodium, methyl bromide, or 

1,3-dichloropropene were the primary active ingredient (Table 4). 
John S. Sanders, Ph.D.

November 8, 2002

Page 5

TABLE 4. Top ten “primary active ingredients” contributing to 2000 VOC emissions in NAA 4, 

Ventura, listed in descending order of total emissions of products containing the primary active 

ingredient. Here the primary active ingredient is defined as the pesticidal active ingredient 

present at the highest percentage in a product. This approach prevents “double-counting” of 

emissions from products containing two active ingredients. 

Primary AI

Total product emissions 

(lbs)

% of all 2001 pesticide 

emissions in NAA4

METHYL BROMIDE 2376024 82.0%

1,3-DICHLOROPROPENE 101339 3.5%

METAM-SODIUM 73718 2.5%

CHLORPYRIFOS 65516 2.3%

CHLOROPICRIN 45975 1.6%

PETROLEUM OIL, 

UNCLASSIFIED 26099 0.9%

METALDEHYDE 20143 0.7%

OXAMYL 16539 0.6%

GLYPHOSATE, 

ISOPROPYLAMINE SALT 15473 0.5%

POTASSIUM N-METHYLDITHIO 

CARBAMATE 11936 0.4%

E. NAA 5, South Coast 

VOC emissions in NAA 5 decreased dramatically early in the 1990s, and have remained at a 

constant relatively low level since 1993 (Figure 1). In 2001, NAA 5 emissions of 1.65 

million lbs were approximately one-third of the 2005 NAA 5 goal of 4.86 million pounds. 

Approximately 57 percent of potential 2001 emissions in NAA 5 were attributable to 

agricultural uses, with commercial structural pesticide applications accounting for the 

remaining 43 percent of emissions. The monthly distribution of NAA 5 emissions is shown 

in Figure 2.

Although the fumigant contribution to 2001 NAA 5 emissions was less than in other NAAs, 

the fumigant products containing methyl bromide and metam-sodium as primary active 

ingredients still comprised 35 percent of the total emissions. The organophosphate and 

pyrethroid insecticides - chlorpyrifos, diazinon, permethrin, cyfluthrin, bifenthrin and 

cypermethrin - contributed 38 percent of total 2001 NAA 5 emissions (Table 5). 
John S. Sanders, Ph.D.

November 8, 2002

Page 6

TABLE 5. Top ten “primary active ingredients” contributing to 2000 VOC emissions in NAA 5, 

the South Coast, listed in descending order of total emissions of products containing the primary 

active ingredient. Here the primary active ingredient is defined as the pesticidal active ingredient 

present at the highest percentage in a product. This approach prevents “double-counting” of 

emissions from products containing two active ingredients. 

Primary AI

Total product emissions 

(lbs)

% of all 2001 pesticide 

emissions in NAA5

METHYL BROMIDE 490767 29.7%

DIAZINON 194101 11.8%

CHLORPYRIFOS 129445 7.8%

PERMETHRIN 102573 6.2%

METAM-SODIUM 84584 5.1%

CYFLUTHRIN 75737 4.6%

CYPERMETHRIN 72203 4.4%

BIFENTHRIN 58163 3.5%

GLYPHOSATE, 

ISOPROPYLAMINE SALT 42294 2.6%

CHLOROPICRIN 31838 1.9%

III. SUMMARY

Similar to last year, the 2001 inventory indicates that the Southeast Desert (NAA 3) and Ventura 

(NAA 4) will experience the greatest difficulty in meeting the 2005 VOC emission goal of 

80 percent of estimated 1990 emission levels. While emissions decreased in both NAAs in 2001, 

both still currently exceed their 2005 targets by very large percentages; 185% in NAA 3 and 

170% in NAA 4. More than 80% of estimated VOC emissions in both NAAs were attributable to 

fumigants, so that achievement of the 2005 goal will be impossible without a marked change in 

fumigant use. 

In contrast to the Southeast Desert and Ventura, the Sacramento Metropolitan Area (NAA 2) and 

San Joaquin Valley (NAA 3) 2001 emissions were both less than the 2005 attainment goal of 

80% of 1990 emissions. This is the first time that the goal has been met in the last decade in 

either NAA. Finally, estimated emissions in the South Coast (NAA 5) are already well below the 

2005 reduction goal as they have been for several years.

Overall, 2001 pesticide VOC emissions decreased almost 20% statewide from the previous year, 

with total statewide 2001 estimated emissions of 35.6 million pounds as compared to 43.6 

million lbs in 2000. These reductions are a direct result of decreased use in 2001 of pesticides

generally and methyl bromide in particular (Figures 3 & 4). 
John S. Sanders, Ph.D.

November 8, 2002

Page 7

VI. REFERENCES

Department of Pesticide Regulation. 2002. News Release 02-018: DPR REPORTS PESTICIDE 

USE DROPPED TO RECORD LOW IN 2001, October 16, 2002. available on-line: 

http://www.cdpr.ca.gov/docs/pur/pur01rep/01_pur.htm, verified November 1, 2002.

Spurlock, F. 2002a. Memorandum to J. Sanders. Summary of 1990-2000 VOC Emissions 

Inventory Data, version 01.12 February 4, 2002. Environmental Monitoring Branch, Dept. 

Pesticide Regulation. available on-line: http://www.cdpr.ca.gov/docs/pur/pur01rep/01_pur.htm, 

verified November 1, 2002.

Spurlock, F. 2002b. Procedures for estimating VOC emissions from pesticides. EH 02-03. 

Environmental Monitoring Branch, Dept. Pesticide Regulation. available on-line: 

http://www.cdpr.ca.gov/docs/pur/pur01rep/01_pur.htm, verified November 1, 2002.

Attachments

cc: Randy Segawa, Senior Environmental Research Scientist (w/Attachments)

Mark Pepple, Senior Environmental Research Scientist (w/Attachments)

bcc: Spurlock Surname File
Potential VOC emissions - NAA 1

Sacramento Metropolitan Area

1990 1992 1994 1996 1998 2000

millions of pounds

1.2

1.4

1.6

1.8

2.0

2.2

2.4

2.6

Figure 1. 1990 - 2001 estimated potential VOC emissions from agricultural

and commercial structural pesticide use by non-attainment area (NAA)

Potential VOC emissions - NAA 2

San Joaquin Valley

1990 1992 1994 1996 1998 2000

14

16

18

20

22

24

26

Potential VOC emissions - NAA 3

Southeast Desert

1990 1992 1994 1996 1998 2000

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

Potential VOC emissions - NAA 4

Ventura

1990 1992 1994 1996 1998 2000

millions of pounds

1.6

2.0

2.4

2.8

3.2

Potential VOC emissions - NAA 5

South Coast

1990 1992 1994 1996 1998 2000

1

2

3

4

5

6

7

Potential VOC emissions 

Statewide

1990 1992 1994 1996 1998 2000

36

38

40

42

44

46

48

50

52

54

2005 goal:

80% of 1990 emissions
Figure 2. 2001 estimated VOC emissions by month in individual NAAs.

note y-axis scale differences among graphs

NAA 1, Sacramento Valley

potential emissions by month in 2001

2 4 6 8 10 12

millions of pounds

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

NAA 2, San Joaquin Valley

potential emissions by month in 2001

2 4 6 8 10 12

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

NAA 3, Southeast desert

potential emissions by month in 2001

2 4 6 8 10 12

0.0

0.1

0.2

0.3

0.4

NAA 4, Ventura

potential emissions by month in 2001

2 4 6 8 10 12

millions of pounds

0.0

0.2

0.4

0.6

0.8

1.0

1.2

NAA 5, South Coast

potential emissions by month in 2001

2 4 6 8 10 12

millions of pounds

0.00

0.05

0.10

0.15

0.20

0.25

0.30
Pounds PUR reported product use by year

1990 1992 1994 1996 1998 2000

lbs use (millions)

220

240

260

280

300

320

340

Number reported pesticide applications/year

1990 1992 1994 1996 1998 2000

count (millions)

1.8

2.0

2.2

2.4

2.6

2.8

Figure 3. Statewide pesticide use 

trends 1990 - 2001
1992 1994 1996 1998 2000 2002

pounds active ingredient (millions)

0

2

4

6

8

10

12

14

16

18

20

MeBr

metam-Na

1,3-D 

Figure 4. California fumigant use 1992 - 2001