B.2 DATA COLLECTION AND EVALUATION
Investigators collected and evaluated data from the following sources for use in the HRA:
Survey. During 1999 RAND conducted a scientific survey of 2,005 Gulf War veterans randomly selected to statistically represent the entire Gulf War population on the ground in the Kuwait Theater of Operations (KTO).[111]
Preventive Medicine (PM) Interviews. Investigators conducted interviews of 252 preventive medicine personnel deployed on the ground in the KTO during the Gulf War who provided specific information on exposures to pesticides and related products. Investigators conducted interviews from February 1998 through November 1999. Tab C-4 contains additional information.
Fly Bait Interviews. Investigators conducted interviews from December 1997 through February 1998 of 35 veterans who provided specific information on fly bait usage on the ground in the KTO during the Gulf War. Tab C-5 contains additional information.
Delousing Interviews. Investigators conducted interviews from November 1998 through December 1999 of 60 personnel who participated in or witnessed delousing of enemy prisoners of war (EPWs). Investigators conducted 35 interviews expressly in connection with delousing, and conducted 25 interviews as part of the PM interviews. Tab C-6 contains additional information.
Records Search. Investigators conducted a search of available contemporaneous deployment-derived information from sources such as the Defense Logistics Agency (DLA) and Armed Forces Pest Management Board (AFPMB). Tab C-7 contains additional information.
The main result of the data collection and evaluation step is the identification of those pesticide formulations to be retained for further evaluation in the HRA.
Many data used in the HRA drawn from the survey, interviews, and published sources are in the form of percentiles. A percentile is a value on a scale of 100 that indicates the percent of the distribution that is equal to or below it. For example, if the 5th percentile value from the survey for exposure duration (ED) is 2 days/month, then we conclude that 5% of servicemembers were exposed 2 days or fewer per month. Likewise, if the 50th percentile for ED is 20 days/month, then we conclude that 50% of servicemembers were exposed 20 or fewer days per month.
A. Exposure Data from Survey and Interviews
In 1999, RAND scientifically surveyed 2,005 Gulf War veterans randomly selected to statistically represent all Gulf War KTO ground troops. RAND conducted the telephone survey from May to October 1999, drawing the sample from Army, Air Force, Marine Corps, and Navy servicemembers who served on the ground in the KTO between August 1, 1990 and July 31, 1991. RAND estimates that 469,047 servicemembers were actually on the ground in-theater during the period of interest. The report, "Pesticide Use During the Gulf War: A Survey of Gulf War Veterans," describes the survey in detail.[112]
Table 7 briefly summarizes pesticide use by service according to the RAND findings. The two major categories of pesticides for survey purposes were "personal-use" pesticides and "field-use" pesticides. Personal-use pesticides are those deliberately applied to skin and/or clothing, while field-use pesticides cover all other types addressed by the survey. The most useful information for the HRA pertains to the two categories of pesticides listed in Table 7. Other types of pesticide products were those applied by certified applicators, and the lindane used for delousing EPWs. The most relevant information on these came from the preventive medicine (PM) interviews, fly bait interviews, and delousing interviews, all covered following this subsection.
Table 7. Survey, percentage of servicemembers estimated to have used pesticides from a given category, by service[113]
Products Used by Servicemembers | Total |
Army |
Marines/Navy |
Air Force |
Personal-use pesticides | 62 |
67 |
57 |
48 |
Field-use pesticides | 49 |
51 |
43 |
50 |
Among other things, servicemembers were asked if they used various personal-use pesticides and if they used or saw others use various field-use pesticides. As can be seen in Table 7, 62% of servicemembers surveyed used personal-use pesticides, while 49% saw and/or used field-use pesticides.
Table 8 presents the most common pesticide products used and/or observed by servicemembers, as determined by the survey. The products are listed in descending order of prevalence within each category. Of the products listed, DEET was associated with the highest usage rate, while benzocaine and flea/tick collars were associated with the lowest. The Army used the highest levels of the pesticides listed, while the Air Force tended to use the lowest levels, although there are three exceptions. Six of the pesticide products listed in Table 8 are quantitatively evaluated later in the HRA, while benzocaine and flea/tick collars are not. The basis for excluding the latter is explained under "Screening of Pesticides for Risk Assessment."
Table 8. Survey, percentage of servicemembers estimated to have used the most common pesticides products, by service[114]
Category |
Product |
Total |
Army |
Marines/Navy |
Air Force |
Personal Use | DEET | 50 |
54 |
46 |
38 |
Permethrina | 44 |
48 |
38 |
36 |
|
Lindane | 7 |
10 |
2 |
1 |
|
Benzocaineb | 3 |
4 |
2 |
1 |
|
Flea/Tick Collars | 3 |
3 |
3 |
1 |
|
Field Usec | Fly baitd | 12 |
12 |
10 |
11 |
d-Phenothrine | 28 |
31 |
20 |
27 |
|
Dichlorvos | 7 |
7 |
5 |
6 |
1) | Assumed to be mainly permethrin, although identified as "personal-use spray." May include some DEET spray as well. Forty percent of PM interviews identified permethrin aerosol. |
2) | The formulation Chigg-Away� , a repellent, includes benzocaine and sulfur. Benzocaine is not actually a pesticide; rather, it is a commonly-used local anaesthetic, included in the formulation to reduce skin irritation. |
3) | Field use dust mentioned was too undefined, as it could have been lindane, carbaryl, diazinon, lime, or other. |
4) | Assumed to be mainly fly baits, but identified as "pellets, crystals, and granules" including azamethiphos and methomyl. Appears to include other products, such as rodent baits. |
5) | Significantly overestimates d-phenothrin usage. Values reflect the inclusion of unknown proportions of various other aerosol products. |
Significant interpretation is necessary to extract the most accurate understanding of conditions in the Gulf based on the information in the survey. For example, Table 8 lists total permethrin usage at 44%. This is based on the survey usage rate for "personal-use spray" rather than the survey usage rate listed for "permethrin." The usage rate of 44% agrees fairly well with the usage rate of 40% for permethrin aerosol determined by the PM interviews. PM personnel are the most knowledgeable servicemembers regarding pesticides products. Permethrin would have been the most common personal-use aerosol spray. Although some DEET may have been present as a "personal-use spray," the best information available indicates that little if any DEET was issued in spray form from within the military supply system. While investigators conducted the interpretation of data carefully, it is possible that some bias was introduced here in extrapolating survey and interview data to the entire servicemember population deployed to the Gulf.
Table 9 and Table 10 present exposure factors of potential use in the HRA. Some of these data are more reliable than others, and investigators handled them accordingly, as the exposure assessment explains. Table 11 presents application rates for resin strips. These application rates are reliable data for risk assessment purposes, since servicemembers would likely have remembered seeing a common product they were probably familiar with. Table 12 provides selected exposure location data by service.
Table 9. Survey, exposure factors for personal-use products[115]
Description | DEET |
Lindane |
Permethrin |
Benzocainea |
Flea/Tick Collarsb |
Events/day |
|||||
5th Percentile | 1 |
1 |
1 |
1 |
-- |
50th Percentile | 2 |
1 |
1 |
1 |
-- |
95th Percentile | 7 |
3 |
4 |
3 |
-- |
Exposure Frequency (days/month) |
|||||
5th Percentile | 4 |
2 |
2 |
2 |
2 |
50th Percentile | 15 |
16 |
20 |
15 |
26 |
95th Percentile | 24 |
27 |
30 |
30 |
30 |
1) | The formulation includes benzocaine and sulfur. |
2) | A dash ("--") indicates that no data were reported. |
Table 10. Survey, exposure factors for field-use products[116]
Description |
d-Phenothrina |
Fly Baitb |
Dichlorvosc |
Events/day |
|||
|
1 |
1 |
-- |
|
1 |
1 |
-- |
|
4 |
2 |
-- |
Exposure Frequency (days/month) |
|||
|
2 |
1 |
-- |
|
30 |
30 |
-- |
|
30 |
30 |
-- |
a) | Assumed to be mainly d-phenothrin, although other active ingredients were identified. |
b) | Assumed to be mainly fly baits, but identified as "pellets, crystals, and granules" containing various active ingredients. Fly baits would be the most familiar products to most personnel. |
c) | A dash ("--") indicates that no data were reported. |
Table 11. Survey, application rates for resin strips[117]
Location |
Percent of Subpopulation Citing Use of Resin Strips a |
|||
Less than 1 strip per 1,000 ft3 |
About 1 strip per |
More than 1 strip per |
Do Not Know |
|
Sleeping quarters | 45 |
13 |
5 |
37 |
Mess halls | 13 |
16 |
8 |
63 |
Other eating locations | 46 |
26 |
27 |
<1 |
Work area | 19 |
1 |
1 |
79 |
Latrine | 6 |
11 |
30 |
53 |
Other | 2 |
9 |
2 |
87 |
a) | Subpopulation of personnel who used or observed use of resin strips (n = 30,530; extrapolated from survey sample of 2,005). |
Table 12. Survey, selected exposure location/facility data (percent)[118]
Category |
Air Force |
Army |
Marines |
Navy |
|
Where stayed | City | 22 |
16 |
9 |
17 |
Tent | 48 |
21 |
31 |
41 |
|
Non-US airbase | 16 |
3 |
4 |
8 |
|
Desert | 5 |
52 |
49 |
25 |
|
Where worked | Building | 30 |
11 |
10 |
9 |
Tent | 15 |
14 |
13 |
23 |
|
Vehicle | 21 |
29 |
18 |
14 |
|
Outdoors | 45 |
63 |
70 |
58 |
|
Where Slept | Building | 38 |
21 |
12 |
30 |
Tent | 51 |
53 |
48 |
59 |
|
Vehicle | 1 |
10 |
8 |
2 |
|
Outdoors | 0 |
12 |
27 |
4 |
|
Where Ate | Building | 31 |
14 |
16 |
27 |
Tent | 48 |
22 |
15 |
26 |
|
Outdoors/other | 16 |
58 |
65 |
45 |
|
Latrine | Part of building | 53 |
16 |
16 |
38 |
Separate structurea | 42 |
69 |
69 |
55 |
a) | May include a small percentage of servicemembers having no structure available. |
2. Preventive Medicine Interviews
Investigators conducted preventive medicine (PM) interviews from February 1998 through November 1999 (Tab C-4). PM personnel are the individuals most likely to have knowledge of pesticide products used in the Army, Navy, and Marines. The PM personnel interviewed included physicians, entomologists, environmental science officers, preventive medicine specialists, and field sanitation team members. In the Air Force, pest controllers are assigned to civil engineering units. Although not technically "preventive medicine" personnel, investigators covered interviews with Air Force pest controllers as part of the PM interviews, and as used below, "PM personnel" generally includes Air Force pest controllers. The PM personnel interviewed included those who were trained in pesticide application, conducted pesticide application, supervised, or witnessed pesticide application during the Gulf War.
Of the approximately 500 PM interviews conducted, investigators identified 252 of these as "exposure interviews." To be classified as an exposure interview, the interviewee had to demonstrate at least some knowledge of pesticide usage on the ground during the Gulf War. Interviews which did not demonstrate this knowledge were excluded. All information gleaned from the interviews is subjective, as it was based on the recollections of the veterans as interpreted and compiled by investigators.
During initial reviews of the PM interviews, it became obvious that, in addition to the mass of complete, correct, and unequivocal information, there was also some incomplete, incorrect, and ambiguous information. Thus, investigators made certain assumptions to interpret such problematic data, where possible, in order to make it useful for exposure assessment. These assumptions were based on the accumulated knowledge of pesticide product availability and usage during the Gulf War. Investigators developed the following set of directions to use when processing the interviews:
1) | In general, make the most conservative assumption. For example, if you only know that Dursban was used, but have no other information, assume that it was 45% chlorpyrifos EC. |
2) | All fly bait purchased outside the US, not otherwise identified, was 1% azamethiphos. |
3) | Military-issue fly bait, or fly bait from other US sources is 1% methomyl. |
4) | A product identified only as fly bait, with no other information, is 1% azamethiphos. |
5) | "Pyrethrum spray" or "pyrethrin spray" used to treat clothing, tents, and/or netting, was 0.5% permethrin aerosol. |
6) | "Pyrethrum aerosol," used as an area spray, was 2% d-phenothrin aerosol. |
7) | "Pyrethrum liquid," used to treat clothing, tents, and/or netting was 40% permethrin liquid. |
8) | "Area spray," not otherwise identified, was 2% d-phenothrin aerosol. |
9) | The only form of lindane used was 1% lindane dust. |
10) | Unless otherwise specified, EPW delousing was carried out with 1% lindane. |
11) | DEET cream or stick was 33% DEET. |
12) | DEET liquid was 75% DEET. |
13) | Any repellent cream, lotion, or stick, not otherwise defined or known, was 33% DEET. |
14) | Any repellent liquid or aerosol spray, not otherwise defined or known, was 75% DEET. |
15) | If no initial concentration was provided, we will assume that the concentration was that for the most common formulation used. |
16) | Any "unknown carbamate liquid" was 14.7% propoxur EC. |
17) | The only forms of diazinon were 48% EC and 2% dust. |
18) | The only form of carbaryl available was the 5% dust. |
19) | "Carbaryl WP" is really bendiocarb 76% WP. |
While we acknowledge that employment of the directions above potentially introduced some bias, we believe that it was necessary in order to use some data for exposure assessment which would otherwise have been incorrect or useless.
The discussion in this subsection centers on Table 13 through Table 15, which present a summary of exposure data from the exposure interviews. The data presented in Table 13 and Table 15 are primarily those which have a direct bearing on the HRA. In order to facilitate discussion of the data presented in Table 13, covering 14 of the 15 pesticides of potential concern (POPCs), the HRA will refer throughout to the "block" numbers listed in the left-hand column (see Section B.2.B, Screening Pesticide Products for Risk Assessment, below for a description of how the POPCs were identified). Lindane (a POPC) is not covered in this section; rather, it is addressed under "Delousing Interviews." Each block is readily identifiable by the thick black line at the top, and the HRA refers to it below as "B#" (e.g., B1 for Block 1). The information presented in the summary tables is limited. The original responses contain much additional information which the tables do not reflect.
Table 13 summarizes formulation-specific exposure data. The table's approach is conservative because (1) all data and statistics are based exclusively on the 252 exposure interviews, and (2) investigators did not count negative responses or responses equal to zero. Although reliance on the 252 exposure interviews may bias the results high, it is necessary because very few of the other servicemembers were in a position to say that pesticide products were not used by their units or that they had not witnessed pesticide use; if anything, they were more likely to say that they just did not remember.
Table 13 presents various statistics, including the number of servicemembers providing a response, and the fraction of the total this represents. "Total" means the 252 exposure interviews, or all responses for a given formulation, as indicated in the table. Also listed, where appropriate, are the 10th percentile, average, and 90th percentile values calculated using Microsoft Excel� based on the specific numerical responses provided by the interviewees. The percentile algorithm will calculate percentile values based on as few as two data points; however, the fewer the data points, the higher the uncertainty. In many cases, the 90th percentile values are equal to the maximum values.
The levels of uncertainty associated with the data presented in Table 13 vary from low to high, depending upon the specific datum in question, but probably tend to be high, in part, because the data are all based on the memories of events that occurred 7-9 years prior to the interviews. Some interviewees stated that they had been deployed to many different locations around the globe over the course of many years, and were unsure sometimes about which things had occurred in which locations. Higher quality data would be possible, for example, if more detailed records had been kept and real-time monitoring, with appropriate quality controls, had been conducted during operations. The level of certainty is also related to the question asked. For example, the interviewees were probably more accurate about the names of the pesticide products used than they were about estimating how many hours per day people were exposed. A detailed explanation of each section of Table 13 follows the table.
Table 13. PM interviews, summary of formulation-specific exposure dataa
Block Number/Descriptionb | ||||||||||||||
B1. Pesticide Products Cited | ||||||||||||||
Total Responses | 78 |
46 |
102 |
19 |
68 |
108 |
16 |
62 |
39 |
42 |
14 |
14 |
27 |
33 |
Fraction of Exposure Interviews | 31% |
18% |
40% |
8% |
27% |
43% |
6% |
25% |
15% |
17% |
6% |
6% |
11% |
13% |
B2. Final Concentration | ||||||||||||||
Number of Responses | 10 |
12 |
9 |
2 |
0 |
0 |
7 |
|||||||
Fraction of Total Responses | 16% |
31% |
21% |
14% |
-- |
-- |
21% |
|||||||
10th Percentile (%) | 1 |
0.3 |
2 |
2 |
-- |
-- |
18 |
|||||||
Average (%) | 13 |
14 |
15 |
8 |
-- |
-- |
70 |
|||||||
90th Percentile (%) | 45 |
44 |
35 |
13 |
-- |
-- |
92 |
|||||||
B3. Individuals Exposed | ||||||||||||||
Number of Responses | 31 |
18 |
43 |
7 |
20 |
50 |
3 |
30 |
17 |
24 |
6 |
6 |
15 |
13 |
Fraction of Total Responses | 40% |
39% |
42% |
37% |
29% |
46% |
19% |
48% |
44% |
57% |
43% |
43% |
56% |
39% |
10th Percentile (%) | 25 |
75 |
13 |
1 |
2 |
1 |
91 |
1 |
1 |
1 |
8 |
1 |
1 |
3 |
Average (%) | 76 |
91 |
76 |
24 |
75 |
62 |
95 |
67 |
48 |
58 |
69 |
36 |
55 |
57 |
90th Percentile (%) | 100 |
100 |
100 |
55 |
100 |
100 |
99 |
100 |
100 |
100 |
100 |
90 |
100 |
100 |
B4. Individuals Wearing PPEc | ||||||||||||||
Number of Responses | 14 |
5 |
15 |
37 |
2 |
27 |
21 |
27 |
8 |
12 |
21 |
20 |
||
Fraction of Total Responses | 14% |
26% |
22% |
34% |
13% |
44% |
54% |
64% |
57% |
86% |
78% |
61% |
||
10th Percentile (%) | 58 |
30 |
100 |
97 |
15 |
73 |
100 |
95 |
85 |
100 |
100 |
75 |
||
Average (%) | 91 |
74 |
94 |
97 |
53 |
92 |
97 |
98 |
94 |
100 |
100 |
95 |
||
90th Percentile (%) | 100 |
100 |
100 |
100 |
91 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
||
B5. Exposure Time | ||||||||||||||
Responses | 30 |
18 |
39 |
8 |
27 |
50 |
8 |
33 |
19 |
24 |
8 |
6 |
17 |
17 |
Fraction of Total Responses | 38% |
39% |
38% |
42% |
40% |
46% |
50% |
53% |
49% |
57% |
57% |
43% |
63% |
52% |
10th Percentile (h/d) | 2 |
2 |
1 |
1 |
1 |
1 |
3 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
Average (h/d) | 14 |
15 |
15 |
3 |
7 |
6 |
11 |
5 |
4 |
3 |
2 |
1 |
2 |
3 |
90th Percentile (h/d) | 24 |
24 |
24 |
9 |
20 |
16 |
22 |
12 |
11 |
6 |
3 |
3 |
4 |
7 |
B6. Exposure Frequency | ||||||||||||||
Number of Responses | 29 |
19 |
39 |
8 |
27 |
53 |
9 |
32 |
18 |
20 |
8 |
7 |
18 |
15 |
Fraction of Total Responses | 37% |
41% |
38% |
42% |
40% |
49% |
56% |
52% |
46% |
48% |
57% |
50% |
67% |
45% |
10th Percentile (d/mo) | 5 |
1 |
1 |
1 |
4 |
1 |
23 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
Average (d/mo) | 22 |
23 |
20 |
11 |
22 |
18 |
27 |
13 |
11 |
10 |
4 |
6 |
8 |
10 |
90th Percentile (d/mo) | 30 |
30 |
30 |
30 |
30 |
30 |
30 |
30 |
30 |
30 |
10 |
12 |
21 |
30 |
B7. Exposure Duration | ||||||||||||||
Number of Responses | 28 |
16 |
36 |
9 |
25 |
50 |
7 |
31 |
17 |
22 |
8 |
6 |
16 |
12 |
Fraction of Total Responses | 36% |
35% |
35% |
47% |
36% |
46% |
44% |
50% |
44% |
52% |
57% |
43% |
59% |
36% |
10th Percentile (mo) | 2 |
2 |
1 |
2 |
3 |
1 |
2 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
Average (mo) | 4 |
5 |
4 |
4 |
5 |
4 |
4 |
4 |
4 |
5 |
3 |
4 |
4 |
5 |
90th Percentile (mo) | 8 |
8 |
8 |
6 |
9 |
8 |
6 |
8 |
9 |
8 |
7 |
7 |
8 |
8 |
B8. Applied to Skin | ||||||||||||||
Number of Responses | 43 |
28 |
8 |
-- |
||||||||||
Fraction of Total Responses | 55% |
61% |
8% |
-- |
||||||||||
B9. Applied to Clothing | ||||||||||||||
Number of Responses | 2 |
3 |
60 |
2 |
||||||||||
Fraction of Total Responses | 3% |
7% |
59% |
11% |
||||||||||
B10. Used Mainly Outdoors | ||||||||||||||
Number of Responses | 27 |
1 |
30 |
62 |
-- |
36 |
25 |
29 |
7 |
5 |
18 |
22 |
||
Fraction of Total Responses | 26% |
5% |
44% |
57% |
-- |
58% |
64% |
69% |
50% |
36% |
67% |
67% |
||
B11. Used Mainly Indoors | ||||||||||||||
Number of Responses | 9 |
15 |
13 |
14 |
9 |
5 |
5 |
7 |
5 |
7 |
3 |
1 |
||
Fraction of Total Responses | 9% |
79% |
19% |
13% |
56% |
8% |
13% |
17% |
36% |
50% |
11% |
3% |
||
B12. Exposed Mainly Outdrs. | ||||||||||||||
Number of Responses | 19 |
1 |
28 |
61 |
-- |
32 |
23 |
28 |
6 |
6 |
16 |
23 |
||
Fraction of Total Responses | 19% |
5% |
41% |
56% |
-- |
52% |
59% |
67% |
43% |
43% |
59% |
70% |
||
B13. Exposed Mainly Indoors | ||||||||||||||
Number of Responses | 10 |
14 |
15 |
16 |
9 |
8 |
5 |
9 |
5 |
6 |
5 |
2 |
||
Fraction of Total Responses | 10% |
74% |
22% |
15% |
56% |
13% |
13% |
21% |
36% |
43% |
19% |
6% |
||
B14. Body Parts Exposed | ||||||||||||||
Hands, arms, face, headd | 38 |
25 |
19 |
8 |
18 |
35 |
2 |
19 |
14 |
14 |
5 |
7 |
10 |
11 |
Entire body | 5 |
3 |
21 |
2 |
-- |
-- |
-- |
4 |
1 |
4 |
-- |
-- |
1 |
1 |
Other parts | - |
- |
2 |
2 |
1 |
2 |
-- |
4 |
2 |
3 |
1 |
-- |
1 |
2 |
a) | Based on 252 preventive medicine (PM) interviews yielding at least some apparently reliable exposure data. See "Exposure Data from Preventive Medicine Interviews" in text for detailed information. Shaded areas are either unnecessary or not relevant. For example, no one would wear PPE to apply DEET to skin. A dash ("--") indicates that there were no responses in this category. |
b) | "Total responses" in B1 means the total number of exposure interviews citing the formulation. "Fraction of Total Responses" in subsequent blocks means the number of responses/total responses. |
c) | PPE = personal protective equipment. Each interviewee was asked to estimate the percent of personnel who wore adequate PPE. Some of those who did not respond to the specific PPE question stated elsewhere that PPE was inadequate. The latter case is not reflected in these data. |
d) | Exposure was reported for one or more of the parts listed. "Head" includes head, face, and neck. |
B1. Pesticide Products Cited presents the number of "hits" for each of the 14 POPCs listed (the 15th POPC, lindane, is addressed under "Delousing Interviews," later). A single hit means that the pesticide product was mentioned one or more times in the course of an interview. Thus, 68 hits for 1% azamethiphos means that 1% azamethiphos was mentioned at least once in each of 68 interviews. The fraction, represented as a percent, equals the number of hits divided by the number of exposure interviews (i.e., 252). The level of certainty associated with the data presented for B1 is high.
B2. Final Concentration presents data on the percent concentration of active ingredient (a.i.) reportedly applied; that is, the final concentration after dilution, if any. For example, the 90th percentile final concentration for chlorpyrifos, 45% liquid (EC) is 45%. What this means is that at least 10% of personnel may have applied undiluted chlorpyrifos EC. This would be a violation of the label under any circumstances.
Investigators consider these values unreliable for the HRA. The actual concentrations applied were difficult for most people to recall, as partly evidenced by the low rates of response. The values listed are generally out of line with how trained applicators (pesticide workers) would most likely have used these formulations. However, there were a small number of apparently reliable reports, based on the level of detail provided, of extremely high application rates for some formulations.
B3. Individuals Exposed presents data on the number of individuals reportedly exposed to each formulation. There is moderate to high uncertainty associated with these data. Some respondents were referring only to applicators, while some were referring to all servicemembers within their units. Also, based on a review of the actual interview narratives, it appears that some interviewees excluded servicemembers wearing personal protective equipment (PPE), while others included those wearing PPE.
B4. Individuals Wearing PPE presents data on applicators wearing PPE. These data are associated with moderate uncertainty. One factor which lowers uncertainty is that respondents were referring only to applicators. However, there are several factors that tend to increase uncertainty. First, since "adequate PPE" was not defined in the interview, some personnel may be referring to applicators who were in fact inadequately protected (e.g., they had gloves, but not respirators when respirators were required). Second, there is a low response rate for most formulations. Finally, the data do not reflect many of the qualitative statements of veterans who did not answer this specific question that they frequently had little or no PPE.
B5 through B7. Data present the exposure times (hours/day), frequencies (days), and durations (months) for each pesticide product. These data are associated with moderate to high uncertainty. The response rates are low for some formulations. Some respondents were referring to applicators only, while some were referring to all members of their units. Recall was clearly a problem.
B8. Applied to Skin presents the numbers of respondents confirming that skin application occurred for DEET and permethrin. One can safely assume that most servicemembers who used 33% DEET deliberately applied it to their skin, while 61% of respondents identified skin application of 75% DEET. Eight percent stated that servicemembers applied permethrin to skin, which constitutes a misuse of the product.
B9. Applied to Clothing presents the numbers of respondents stating that pesticide products were applied to clothing. Permethrin was by far the most widely applied, as expected. It is noteworthy interviewees did not identify 75% DEET liquid as being used very much for clothing application, as military guidance issued following the Gulf War specified clothing application as the only appropriate use for 75% DEET.[119] Chances are, troops applied much more DEET to clothing than is reflected here, since clothing application was an intended purpose of DEET, and such application would have enhanced protection against pests. It seems unlikely that much d-phenothrin was deliberately applied to clothing; only two respondents identified this use of d-phenothrin, and they may have been referring to incidental and/or infrequent application rather than intentional and/or frequent application. No further information on this issue was obtained.
B10 and B11. Data describe the predominant location of pesticide product use as either outdoors or indoors; that is, outside or inside any enclosed structure, including a tent. Low response rates for some of the formulations limit data usability for the HRA, and the actual differences for some formulations are highly uncertain. For example, 26% said permethrin was used mainly outdoors, while 9% said it was used mainly indoors. It would be useful to know where the other 65% recalled seeing it used. On the other hand, some of the responses confirm what would be expected. For example, 91% malathion was reportedly used outdoors the majority of the time. Despite the shortcomings of the data, it is safe to conclude that most pesticide products were used more outdoors than indoors, with the exception of dichlorvos, d-phenothrin, and bendiocarb. Consideration of outdoor versus indoor use is irrelevant for DEET, since an individual is in continuous contact with it once applied.
B12 and B13. Data describe the predominant exposure point to the pesticide product as either outdoors or indoors. There is a high level of agreement between B10 and B12, and B11 and B13, indicating respondents answered conscientiously. This fact may be viewed as increasing the reliability of these answers, although the low response rate for some formulations has the opposite effect.
B14. Body Parts Exposed presents the numbers of veterans reporting that various body parts were predominantly exposed to pesticide products. As expected, the greatest dermal exposure for most of the pesticide products used was to hands, arms, face, head, and/or neck. The only exception is permethrin, where about half of those providing an answer to this question indicated predominant exposure was whole body. Few PM personnel indicated that other parts were exposed.
All the pesticides and related products identified in the PM exposure interviews were ranked in Table 14 based on the "hit" rate. Each interview mentioning a given pesticide product at least once counts as a hit. The level of certainty associated with the data presented for Table 14 is high.
Table 14. PM interviews, pesticide product rankings
Pesticide Product |
Hitsa |
Rateb |
Rank |
Pesticide Product |
Hitsa |
Rateb |
Rank |
|
Methomyl, 1% crystals | 108 |
43% |
1 |
Flystick | 3 |
1.2% |
24 |
|
Permethrin, 0.5% aerosol | 102 |
40% |
2 |
Allethrin/resmethrin, 0.35% aerosol | 2 |
0.8% |
25 |
|
DEET, 33% stick/cream | 78 |
31% |
3 |
Aluminum phosphide | 2 |
0.8% |
25 |
|
Azamethiphos, 1% crystals | 68 |
27% |
4 |
Chigg Away� | 2 |
0.8% |
25 |
|
Chlorpyrifos, 45% liquid (EC) | 62 |
25% |
5 |
Diazinon, 2% dust | 2 |
0.8% |
25 |
|
DEET, 75% liquid | 46 |
18% |
6 |
OFF� | 2 |
0.8% |
25 |
|
Lindane, 1% dust | 44 |
17% |
7 |
Pindone | 2 |
0.8% |
25 |
|
Malathion, 57% liquid (EC) | 42 |
17% |
8 |
Pyrethroids | 2 |
0.8% |
25 |
|
Diazinon, 48% liquid (EC) | 39 |
15% |
9 |
Small pellets for mosquito | 2 |
0.8% |
25 |
|
Malathion, 91% liquid (ULV) | 33 |
13% |
10 |
Stick paper | 2 |
0.8% |
25 |
|
Chlorpyrifos, 19% liquid (ULV) | 27 |
11% |
11 |
Carbamate | 1 |
0.4% |
26 |
|
d-Phenothrin, 2% aerosol | 19 |
8% |
12 |
Chlordane | 1 |
0.4% |
26 |
|
Brodifacoum | 18 |
7% |
13 |
Chlorpyrifos powder | 1 |
0.4% |
26 |
|
Dichlorvos, 20% plastic strip | 16 |
6% |
14 |
Chlorophyll | 1 |
0.4% |
26 |
|
Bendiocarb, 76% solid (WP) | 14 |
6% |
15 |
Combat� (amidinohydrazone) | 1 |
0.4% |
26 |
|
Propoxur, 14.7% liquid (EC) | 14 |
6% |
15 |
Kuwaiti OP powder | 1 |
0.4% |
26 |
|
Pyrethrum, 1.4% liquid | 14 |
6% |
15 |
Neocidol� (diazinon) | 1 |
0.4% |
26 |
|
Flea & tick collars | 13 |
5% |
16 |
No-Fly� (fly bait) | 1 |
0.4% |
26 |
|
Azamethiphos, 10% solid (WP) | 10 |
4% |
17 |
One-way fly trap | 1 |
0.4% |
26 |
|
Pyrethrin, 90% liquid (capsules) | 9 |
4% |
18 |
Parathion | 1 |
0.4% |
26 |
|
Carbaryl, 5% dust | 8 |
3% |
19 |
Pentachlorophenol | 1 |
0.4% |
26 |
|
Permethrin, 40% liquid | 8 |
3% |
19 |
d-Phenothrin, 80% liquid | 1 |
0.4% |
26 |
|
Warfarin | 7 |
3% |
20 |
Pyrethrum spray | 1 |
0.4% |
26 |
|
DDT | 6 |
2% |
21 |
Red jelly | 1 |
0.4% |
26 |
|
Propoxur, 1% liquid | 6 |
2% |
21 |
Resmethrin | 1 |
0.4% |
26 |
|
Propoxur, 70% solid (WP) | 5 |
2% |
22 |
Skin So Soft� | 1 |
0.4% |
26 |
|
Rat poison | 4 |
2% |
23 |
Sticky traps | 1 |
0.4% |
26 |
|
Cypermethrin | 3 |
1% |
24 |
Temephos | 1 |
0.4% |
26 |
a) Based on 252 PM exposure interviews. Each interview mentioning the pesticide product at least once counts as a hit. |
b) (Hits/252) x 100. |
Table 15 presents a brief summary of other exposure data collected during the PM interviews. When asked about exposure route, most interviewees felt that the dermal route was the main one, with inhalation a close second. Only about 2% felt that the oral route was of concern. Most servicemembers were quartered in GP-medium tents, and most respondents reported that their quarters were very dusty. Almost half reported that the wind commonly penetrated quarters. Pesticide-contaminated dust may have been an issue for some servicemembers. On the other hand, wind penetrating quarters would dilute potential inhalation exposures.
Table 15 indicates a few other points worth noting. At least 12% of interviewees believed specific documentation may have existed regarding pesticide product use and/or exposures. At least 17% of interviewees provided information on pesticide product disposal practices. Seven percent of interviewees could describe specific incidents of overexposure to pesticide products that caused an immediate reaction or symptoms. Fifteen percent of interviewees witnessed host nation preparation and application of pesticide products.
The survey and the PM interview results are not directly comparable, as investigators undertook each component for a different purpose, employing radically different methods. Despite this, there is reasonable agreement regarding reported usage rates for DEET, permethrin, and dichlorvos. There appear to be significant discrepancies for fly baits and d-phenothrin. The survey indicates that there was a 12% usage rate for fly baits, while the PM interviews indicate a rate of at least 43%. For d-phenothrin, apparent usage rates were 28% versus 8% from the survey and PM interviews, respectively. The survey usage rates for fly baits and d-phenothrin are likely overestimates.
Table 15. PM interviews, summary of other exposure data
Item |
Category |
Numbera |
Fractionb |
Exposure route | dermal | 137 |
54% |
inhalation | 116 |
46% |
|
oral | 6 |
2% |
|
Description of quartersc | urban | 73 |
29% |
non-urban | 73 |
29% |
|
building | 89 |
35% |
|
GP-large tent | 48 |
19% |
|
GP-medium tent | 157 |
62% |
|
GP-small tent | 29 |
12% |
|
other tent | 40 |
16% |
|
windy inside | 111 |
44% |
|
dusty inside | 130 |
52% |
|
Documentation generated | medical records | 7 |
3% |
supply records | 7 |
3% |
|
logs | 29 |
12% |
|
other | 31 |
12% |
|
Pesticide product disposal methods | burned | 24 |
10% |
buried | 31 |
12% |
|
other | 43 |
17% |
|
The interview contains other useful information on pesticide product exposure | yes | 69 |
27% |
The veteran is aware of incidents of overexposure | yes | 18 |
7% |
The veteran witnessed host nation preparation and application of pesticide products | yes | 38 |
15% |
a) | Number of veterans responding as indicated. |
b) | Fraction of 252 exposure interviews. |
c) | Fraction is greater than 100% because many individuals were quartered in multiple ways. |
Early in the pesticides exposure investigation it became apparent that troops used fly baits widely during the Gulf War. Consequently, investigators completed 35 interviews, addressing mainly fly baits, from December 1997 through February 1998 (Tab C-5). The RAND survey confirmed the prevalence of fly baits, as did the PM interviews. Table 16 summarizes the qualitative and quantitative exposure information from the fly bait interviews.
Table 16. Fly bait interviews, summary of exposure dataa
Lead ID |
Branch |
PG Unit |
Fly Bait Description |
Exposure Factors |
|||||||
Application Description | Specific Locationsb | Hours/ Day |
Days/ Month |
Months |
Routes |
Conditions |
Sleeping Quarters |
||||
7150 |
Army |
226th Maintenance Company |
yellow, greenish-white crystals |
procured in 25 lb. cans; 2 mayonnaise jar lids full at a time - replace every 2 days | sleeping quarters; mess hall | 24 |
30 |
9 |
oral, dermal, & inhalation |
very dusty, filthy |
GP medium |
7151 |
Army |
2nd Bn 505th Infantry |
yellow crystals |
heaped onto paper plates (~6 in mess) | latrines, mess tent | 3 |
30 |
3 |
-- |
-- |
concrete building |
7153 |
Army |
201st Field Artillery |
granules translucent blue |
put in 5-gal troughs out- side tents | outside showers, mess, latrines | 24 |
30 |
1 |
-- |
windy |
GP large |
7154 |
Army |
445th MP Co, 89th MP Bde |
Snip�; pinkish, red, granules; yellow granules |
water added to crystals in cut out 2-L bottle - 4 in GP; 2 in latrine | latrines, sleeping tent, cabin tents, outside kitchen tent | 6.5 |
30 |
6 |
-- |
-- |
GP medium |
7156 |
Army |
47th Ordnance Det. (EOD) |
Snip�: bright colored red and yellow crystals |
a few cups in mess tray; sprinkled under toilets | common areas, latrines, tents | 4.5 |
30 |
1 |
oral, dermal, & inhalation |
airy in sleeping tent |
Iraqi tent |
7159 |
Army |
311th MI Bn, 101st Air Assault |
yellow |
1.5 cups on each side of GP door | mess, outside sleeping quarters | 16 |
30 |
4 |
-- |
-- |
GP small (Saudi Pilgrim) |
7160 |
Marines |
2nd MARDIV FW Comm CP |
red, blue, yellow granules |
placed in low styrofoam trays (6x9x1/2 in) - 50 in mess hall | 1,750 ft2 mess hall | 1.5 |
30 |
1 |
-- |
-- |
-- |
7161 7162 |
Marines |
Direct Support Command (Forward) |
yellow powder |
procured in cans (~1 gal) | floor of latrines, outside perimeter of GP, including doorways | 8 |
21 |
1 |
oral, dermal, & inhalation |
windy |
GP large |
7171 |
Army |
D CO 123rd Support Bn |
yellow granules |
outside perimeter, including doorways | all tents, showers, latrines | 4 |
30 |
5 |
oral, dermal, & inhalation |
windy, dusty |
GP med |
7172 |
Army |
1st Bn, 7th Cavalry, Div Scouts |
red, purple, gray, green, yellow granules |
1 cup 2x/day in GP; sprinkle on shelves or floor of latrine | tents, latrines, showers, depots, hospital, under cots | 9 |
30 |
7 |
oral, dermal, & inhalation |
windy, dusty |
GP small |
7175 |
Army |
197th Infantry Bde |
orange-red crystals |
1" in cut-out 1.5-L water bottle + water; place by doors & in center; replace daily | GP, Technical Operations Center | 24 |
30 |
3 |
oral, dermal, & inhalation |
-- |
GP medium |
7176 |
Army |
2/52nd ADA |
green powder |
Sprinkled | by latrines | 0.25 |
30 |
3 |
-- |
-- |
-- |
7181 |
Army |
37th Engr Bn, 82nd Abn Div |
red granules |
sprinkled on ground/latrine; | latrine, outside dining area, in living quarters | 9 |
30 |
3 |
-- |
-- |
-- |
7182 |
Army |
72nd Engr Co, 197th Inf Bde |
yellow granules |
~1/8 cup spread on flat surface; sprinkled | latrine floors, outside by armored personnel carriers, | 18 |
30 |
1 |
oral, dermal, & inhalation |
-- |
-- |
7183 |
Army |
2nd Armored Cavalry, 1st Squadron |
green powder similar to fine sand |
4 small cans (~4 oz) in la- trine; 10 outside GP; replaced every 2 days | Inside and outside latrines; outside GP | 12 |
30 |
7 |
-- |
dry & windy |
GP small |
7184 |
Army |
526th Signal Co, 11th Signal Bde |
yellow crystals |
mess: 3 tsp per ea of 25 tables in cut- out bottom of a soda can; 4 oz/latrine | latrines, mess tent, motor pool | 1 |
30 |
5 |
-- |
-- |
-- |
7190 |
Army |
1st Bn 325th PIR, 82nd Abn |
yellow, in 8 oz plastic bags |
24 bags placed outside WH; several outside latrine; 4 in trailer; replaced daily | outside warehouse; outside latrine; inside kitchen trailer | 16 |
30 |
9 |
-- |
-- |
warehouse |
7192 |
Army |
3rd Bn, 73rd Armor, 82nd Abn Div |
fly bait |
outside tents; 2-3 cups put in bowl on dining table; 2 x 12 oz cans in GP med | sleeping quarters, dining tables | 11 |
30 |
7 |
oral, dermal, & inhalation |
-- |
GP medium |
7193 |
Army |
C Company, 5th Eng., 24th ID |
yellow and orange crystals |
0.5-1 cup in plate every 6-12 hrs | sleeping quarters, dining tables, latrines | 18 |
30 |
8 |
oral, dermal, & inhalation |
windy, dirty, and sandy |
GP medium |
7196 |
Army |
Bravo, 2nd Bn, 82nd Aviation |
fly bait |
0.5 inch in pie tin; 1 tin in latrine, 3 in quarters; every 5 ft along wall in mess; replaced every 2 days | sleeping quarters, mess area, latrines | 11 |
30 |
5 |
oral, dermal, & inhalation |
-- |
GP large |
7199 |
Army |
307th Engr. Bn, 82nd Aviation |
multi-colored pellets or grains |
0.5 cup/tray | sleeping quarters, mess area, latrines | 12 |
30 |
7.5 |
oral, dermal, & inhalation |
-- |
Building; air-conditioned |
7200 |
Army |
159th Corps Support Group, 1st Infantry |
fly bait |
0.25 coffee can; replaced every 12 hours | sleeping quarters, Tactical Operations Center (GP medium) | 21 |
30 |
6 |
oral, dermal, & inhalation |
dusty |
GP medium |
7202 |
Army |
Alpha Co., 24th Signal Bn, 24th ID |
Saudi fly bait; Arabic label |
put on saucers and sprinkled around bunk | sleeping quarters, latrines | 6 |
30 |
8 |
oral, dermal, & inhalation |
windy; constantly dusty |
GP medium |
7231 |
Marines |
EOD, 1st Marine Div |
fly bait |
2-6 tablespoons in sleeping tent | sleeping quarters, mess tent | 24 |
30 |
1.5 |
oral, dermal, & inhalation |
-- |
GP medium |
7253 |
Army |
2nd ACR |
purple granules |
0.5 lb/location sprinkled on ground | on ground outside mess trailers, latrine | 1.5 |
30 |
6 |
inhalation |
-- |
-- |
7254 |
Army |
307th Eng, 82nd ABN |
red, white, yellow granules |
1 cup sprinkled directly onto shelf | 3-holer latrines (15 altogether) | 1 |
30 |
6 |
oral, dermal, & inhalation |
windy |
-- |
7255 |
Army |
7th Corps, 14th MP Bde, 66th MP Co |
yellow, pink granules (Arabic label) |
placed in 12-oz soda can cut in half; sprinkled in tents | sleeping quarters, mess tent, latrines - in corners, under cots | 19 |
30 |
5 |
oral, dermal, & inhalation |
-- |
Squad tents |
7257 |
Army |
3rd Armored Cavalry |
fly bait - "moth ball crystals" |
placed in 12-oz soda can cut in half; sprinkled in tents | sleeping quarters, latrines | 6 |
30 |
2 |
oral, dermal |
-- |
Tents, M577 track vehicle, outside, trailers |
7270 |
Army |
HHC, 3rd Armored Cav Reg, Ft Bliss/1 |
multi-colored, red, yellow, blue |
1 cup put in box | latrines | 1 |
30 |
6 |
inhalation |
-- |
-- |
7272 |
Army |
350th Evac Hospital |
fly bait |
-- |
latrines, mess | 1 |
30 |
3.5 |
inhalation |
-- |
-- |
7280 |
Army |
141st Field Artil Bn, 24th Infantry |
reddish crystals (like rock salt) |
placed in latrines; outside GP mess | in latrines, outside GP, outside mess | 24 |
30 |
7 |
oral, dermal, & inhalation |
-- |
GP medium |
7290 |
Army |
1st Platoon, Bravo, 1-504th PIR, 82nd Abn |
reddish granules |
spread everywhere in large quantities | living quarters, mess tents, latrine, shower | 24 |
30 |
6 |
windy, dusty |
hangar |
|
7372 |
Army |
A Co. 1st/159th Aviation |
purple and neon green crystals |
sprinkled liberally all over camp outside tents | on picnic tables used for eating, physical training, recreation | 4 |
30 |
7 |
oral, dermal, & inhalation |
very windy and dusty |
GP medium |
7390 |
Army |
Co A, 2nd Bn, 5th SF Group |
yellow granules |
1 cup put in bottom of water bottles | living quarters, mess, latrines; under cots, and inside mosquito netting | 11 |
30 |
4 |
oral, dermal, & inhalation |
-- |
-- |
|
10th Percentile | 1 |
30 |
1 |
|||||||
Average | 11 |
30 |
5 |
||||||||
90th Percentile | 24 |
30 |
8 |
a) | Interviews were conducted December 1997 to February 1998. A dash ("--") indicates that no information was provided, or that the item is not applicable. |
b) | Locations are assumed to be inside, unless noted otherwise. |
Investigators used a total of 60 interviews to evaluate exposure to lindane dust. Delousing of thousands of enemy prisoners of war (EPWs) was a specialized function carried out exclusively or almost exclusively by military police (MPs). The best information available indicates that lindane, 1% powder was virtually the only formulation used by US servicemembers for delousing EPWs. UK troops reportedly used a malathion formulation. Twenty-five of the preventive medicine interviews provided information about delousing. To better capture the details of the process, investigators completed 35 additional interviews of servicemembers likely to be knowledgeable about delousing, from November 1998 through December 1999 (Tab C-6). Table 17 summarizes exposure data from all 60 delousing interviews.
Table 17. Delousing interviews, summary of exposure dataa
Paraphrased Question |
Answer Category |
Respondingb |
Calculated Value |
|
No. |
Fraction |
|||
1. Which chemicals were used for delousing? | Lindane | 40 |
67% |
-- |
White powder | 12 |
20% |
-- |
|
Answer provided | 52 |
87% |
-- |
|
2. What was the form of the product used for delousing? | Powder | 53 |
88% |
-- |
3. What type of dispersal equipment was used? | Power driven | 14 |
23% |
-- |
Manually operated pump | 14 |
23% |
-- |
|
Shaker can | 3 |
5% |
-- |
|
Other | 8 |
13% |
-- |
|
More than one | 6 |
10% |
-- |
|
Answer provided | 45 |
75% |
-- |
|
4. What was the output rate of the equipment used? | Answer provided | 0 |
0% |
-- |
5. Which of the following items of protective equipment were used by most personnel conducting delousing operations? | Respirators | 2 |
3% |
-- |
Gloves | 16 |
27% |
-- |
|
Respirators and Gloves | 15 |
25% |
-- |
|
None | 11 |
18% |
-- |
|
Answer provided | 44 |
73% |
-- |
|
6. Did personnel conducting delousing: | Inhale lindane powder? | 31 |
52% |
-- |
Have skin contact | 27 |
45% |
-- |
|
with lindane powder? | ||||
Inhale malathion? | 0 |
0% |
-- |
|
Have skin contact | 0 |
0% |
-- |
|
with malathion? | ||||
Have any other | 1 |
2% |
-- |
|
type of exposure? | ||||
Answer provided | 34 |
57% |
-- |
|
7. Was delousing conducted outdoors or indoors? | Outdoors | 14 |
23% |
-- |
Indoors | 30 |
50% |
-- |
|
Outdoors and indoors | 2 |
3% |
-- |
|
Answer provided | 46 |
77% |
-- |
|
8. How did personnel involved in delousing operations clean up prior to breaks? | Washed hands | 1 |
2% |
-- |
Washed face | 0 |
0% |
-- |
|
Showered | 0 |
0% |
-- |
|
More than one | 12 |
20% |
-- |
|
Did nothing | 5 |
8% |
-- |
|
Answer provided | 18 |
30% |
-- |
|
9. How would you describe the usual wind conditions during delousing? | Usually fairly calm | 8 |
13% |
-- |
Usually somewhat windy | 20 |
33% |
-- |
|
Usually very windy | 2 |
3% |
-- |
|
Answer provided | 30 |
50% |
-- |
|
10. Are you aware of any incidents in which US personnel experienced an immediate reaction from lindane? | Yes | 1 |
2% |
-- |
Answer provided | 1 |
2% |
||
11. What was the approximate weight of lindane applied to each EPW? | 10th Percentile (oz) | -- |
-- |
3 |
Average (oz) | -- |
-- |
12 |
|
90th Percentile (oz) | -- |
-- |
24 |
|
Answer provided | 6 |
10% |
-- |
|
12. What was the length of time required to delouse a single EPW? | 10th Percentile (min) | -- |
-- |
1 |
Average (min) | -- |
-- |
2 |
|
90th Percentile (min) | -- |
-- |
5 |
|
Answer provided | 21 |
35% |
-- |
|
13. How many hours each day were you able to smell or see pesticide in the air during delousing operations? | 10th Percentile (h/d) | -- |
-- |
2 |
Average (h/d) | -- |
-- |
11 |
|
90th Percentile (h/d) | -- |
-- |
20 |
|
Answer provided | 14 |
23% |
-- |
|
14. How many hours per day was a US soldier typically involved in delousing? | 10th Percentile (h/d) | -- |
-- |
4 |
Average (h/d) | -- |
-- |
9 |
|
90th Percentile (h/d) | -- |
-- |
12 |
|
Answer provided | 38 |
63% |
-- |
|
15. How many days/month might an individual US soldier have worked under conditions in which the pesticide could be smelled or seen? | 10th Percentile (d/mo) | -- |
-- |
7 |
Average (d/mo) | -- |
-- |
17 |
|
90th Percentile (d/mo) | -- |
-- |
30 |
|
Answer provided | 37 |
62% |
-- |
|
16. How many months were personnel involved in delousing?c | 10th Percentile (mo) | -- |
-- |
1.0 |
Average (mo) | -- |
-- |
1.9 |
|
90th Percentile (mo) | -- |
-- |
3.0 |
|
Answer provided | 42 |
70% |
-- |
a) | Based on 60 interviews comprising 35 delousing interviews and 25 preventive medicine interviews. The questions asked varied somewhat between the two types of interviews, and this accounts for the low apparent response rate on some questions. The questions listed are those that were intended to provide potentially relevant exposure data. A dash ("--") indicates that the item is not applicable. |
b) | Provides the number and percent responding per the associated answer category. |
c) | Limited to 3 months based upon known EPW processing period. The few reports of exposure durations exceeding 3 months are not reliable. |
Table 17 confirms that lindane was the most widely-used formulation. In the course of the 60 interviews, no one identified any product other than lindane, although some did not specify the active ingredient. The dispersal equipment most frequently used included power devices and manual pumps. No one could recall the output rates used. Army guidance required applicators to wear specific PPE components, including BDUs, respirators, and gloves.[120] The appropriate respirator would have been a half-face respirator with organic vapor cartridges and pesticide prefilters, while the appropriate gloves would have been natural or synthetic rubber gloves.[121] The answers to Question 5, and the detailed responses provided to the interviewers indicate 25% of applicators wore respirators and gloves together. Whether the respirators and gloves referred to met military standards is unknown, as the interview questions were not specific to this level of detail. At least 18% of personnel reportedly wore no PPE, and about 45% did not wear respirators.
Question 6 answers indicate about 50% of applicators inhaled lindane, and/or had dermal contact with lindane. Applicators conducted delousing in a tent about half the time (Q. 7). About 22% of respondents indicated that applicators made some efforts to clean up prior to breaks (Q. 8), and 8% did nothing; however, 70% of interviewees did not answer the question. Only one interviewee said he was aware of incidents where US troops experienced an immediate reaction (" it burned their skin") to lindane (Q. 10). The interviews did not produce usable information on the approximate weight of lindane applied to each EPW (Q. 11). According to the percentile values calculated for Question 11 responses, 10% or fewer interviewees stated that 3 oz of lindane dust were applied to each EPW, while 90% or fewer interviewees stated that 24 oz of lindane dust were applied to each EPW. In fact, 24 oz was the maximum reported, and was reported by a single interviewee. Only 10% of interviewees answered Question 11, and the answers appear to be unreasonably high based on military guidance.
The summary statistics for exposure time (Q. 14), exposure frequency (Q. 15), and exposure duration (Q. 16) are associated with a moderate to low level of uncertainty. Note, however, that the 90th percentile value of 3 months is not a value calculated based on the interviews (which is considerably higher), but is based on the known maximum length of time (in months) that EPW processing occurred.
B. Screening Pesticide Products for Risk Assessment
Most of the pesticides and related products identified as potentially used during the Gulf War are well known to produce adverse health effects in animals and/or humans if applied at sufficient concentrations under certain conditions, and are recognized by EPA as being at least moderately toxic. However, most of them posed little or no health threat given the combinations of their prevalence, toxicity, and the ways in which they would have almost certainly been handled in the field.
Table 18 presents 64 pesticides and related products identified from specific sources as possibly used during the Gulf War. Such sources include the survey, PM interviews, and records searches described above. Where possible, investigators listed pesticide products by the probable formulations used; thus, there are many trade names not listed in Table 18. However, Table 18 also lists a number of infrequently cited miscellaneous products from the PM interviews. Investigators identified a subset of 15 pesticides for thorough evaluation in the HRA, known as the "pesticides of potential concern" (POPCs) from the complete set listed in Table 18. The POPCs are the ones which would have posed the greatest potential hazard to servicemembers during the Gulf War due to their prevalence, toxicity, and manner of use.
Table 18. Screening summary of pesticides and related products
Pesticide Product |
Retained for Further Evaluationa |
Basis for Exclusionb |
Allethrin/resmethrin, 0.35% aerosol | No |
A |
Aluminum phosphide | No |
A,D |
Amidinohydrazone | No |
A,E |
Azamethiphos, 1% crystals | Yes |
-- |
Azamethiphos, 10% solid (WP) | No |
A |
Bacillus thurengiensis | No |
B,D,E |
Bendiocarb, 76% solid (WP) | Yes |
-- |
Boric acid | No |
B,D,E |
Brodifacoum | No |
E |
Bromadiolone | No |
E |
Carbamate | No |
A,G |
Carbaryl, 5% dust | No |
A,D |
Chigg-Away� | No |
A,E |
Chlordane | No |
A,D |
Chlorophacinone | No |
D,E |
Chlorophyll | No |
A,C,D,G |
Chlorpyrifos, 19% liquid (ULV) | Yes |
-- |
Chlorpyrifos, 45% liquid (EC) | Yes |
-- |
Chlorpyrifos powder | No |
A,C |
Combat� | No |
see "Amidinohydrazone" |
Cypermethrin | No |
A |
DDT | No |
A,D |
Deltamethrin | No |
B |
Diazinon, 48% liquid (EC) | Yes |
-- |
Diazinon, 2% dust | No |
A,C |
Dichlorvos, 20% plastic strip | Yes |
-- |
DEET, 33% stick/cream | Yes |
-- |
DEET, 75% liquid | Yes |
-- |
Diphacinone | No |
E |
Ethyl hexanediol | No |
A,C |
Flystick | No |
E |
Kuwaiti OP Powder | No |
A,C,D,G |
Lindane, 1% dust | Yes |
-- |
Malathion, 57% liquid (EC) | Yes |
-- |
Malathion, 91% liquid (ULV) | Yes |
-- |
Methomyl, 1% crystals | Yes |
-- |
Neocidol� (diazinon) | No |
A,C,D |
No-Fly� | No |
A,D |
OFF� | No |
A |
One-way fly trap | No |
A,C,D,E |
Parathion | No |
A,D |
Pentachlorophenol | No |
A,C |
Permethrin, 0.5% aerosol | Yes |
-- |
Permethrin, 40% liquid | No |
A |
Pet flea and tick collars | No |
A,C |
d-Phenothrin, 2% aerosol | Yes |
-- |
d-Phenothrin, 80% liquid | No |
A,D |
Pindone | No |
D,E |
Propoxur, 1% liquid | No |
A,C |
Propoxur, 14.7% liquid (EC) | Yes |
-- |
Propoxur, 70% solid (WP) | No |
A,D |
Pyrethrin, 90% liquid (capsules) | No |
A,D |
Pyrethroids | No |
A,C,D,G |
Pyrethrum, 1.4% liquid | No |
C,F |
Pyrethrum spray | No |
A,C,D,G |
Red Jelly | No |
A,D,G |
Resmethrin | -- |
See "Allethrin/resmethrin." |
Rat poison | No |
E |
Skin-so-Soft� | No |
A,D |
Small pellets for mosquito | No |
A |
Stick Paper/Sticky Traps | No |
E |
Temophos | No |
A,D |
Valone | No |
E,D |
Warfarin | No |
E,D |
a) | A dash ("--") indicates that an entry is not necessary because the pesticide product was not excluded. |
b) | The bases for exclusion are as follows: |
A = Cited in less than or equal to 5% of preventive medicine (PM) exposure interviews. | |
B = Not cited in PM exposure interviews. | |
C = Cited by less than or equal to 5% of survey respondents. | |
D = Not specifically named or otherwise indicated by survey report. Presumably named by few if any respondents. | |
E = Low potential for toxicity under the conditions of use that most likely existed during the Gulf War. | |
F = Although listed in 6% of PM interviews, several of the interviews were probably referring to other products such as permethrin or d-phenothrin, which were retained. | |
G = not specific/unknown/misidentified. |
Investigators retained a pesticide product if it was cited in greater than 5% of the survey sample and/or PM interviews, and if it had a significant potential for toxicity under the conditions of use that most likely existed during the Gulf War.[122]
Investigators eliminated a pesticide product if it was deemed to have a low potential for toxicity under the conditions of use that most likely existed during the Gulf War. Details regarding the toxicity of the pesticide products listed in Table 18 may be found in a variety of sources, including the RAND Pesticides Literature Review,[123] Tab C-3, and four websites, as follows:
Investigators eliminated several types of formulations, chemicals, or other products identified as "pesticide products," at least partly, because of low toxicity under the conditions of use that most likely existed during the Gulf War. Such types included:
PM personnel used anticoagulants for rodent control; anticoagulants exert toxicity only following ingestion. Products containing low concentrations of anticoagulants were provided as baits, placed near locations where rodents were expected to appear, such as rodent burrows. Some of the active ingredients and products include brodifacoum, warfarin, pindone, and "rat poison." While it is possible to describe a scenario where troops could have been exposed to anticoagulants via ingestion, we are justified in assuming that the amounts that could have been ingested would have been too small to be of consequence. For example, it is possible that rodents transferred contaminated material from paws to food, food storage areas, or food preparation surfaces, but the mass of material would be very small.
PM personnel used various traps to hold insects fast or kill them by slowly releasing a chemical in the immediate vicinity of the trap. The majority of these traps worked exclusively by holding the insect fast, and contained no pesticide active ingredient. Furthermore, those traps containing pesticide active ingredients would have released far too little chemical to have been of any health consequence to humans. The products (generic terms) included flystick, stick paper, one-way fly trap, and sticky trap.
Bait stations were small containers that contained baits attractive to the target pests. The bait stations were provided in closed containers, which had small holes opened immediately prior to placement in a location where they would be readily accessible to the pests. The pests would then crawl inside and consume the bait. There would have been little opportunity for human contact with the active ingredients. A typical example of such a bait station contained amidinohydrazone (Combat�) and was placed on floors for control of cockroaches.
Some personnel provided information on products referred to here as "non-specific/unknown/misidentified." There are few reports in this category, and partly for this reason, they are of little consequence. In any case, investigators identified insufficient information from these reports to include these products in the HRA. Examples of products in this category include Kuwaiti organophosphate (OP) powder, carbamate, pyrethroids, red jelly, and chlorophyll.
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