Chapter Four: Living Conditions and Variations in Pesticide Use

LIVING AND WORKING CONDITIONS IN THE GULF

Table 4.1 shows where service members reported staying most of the time during the month recorded in the survey. The fraction of personnel in each type of location varied by service, with roughly half of the Army and Marine Corps personnel stationed in the desert, and with most of the remainder in tent cities. In contrast, almost half of the Air Force personnel were located in tent cities, with most of the rest in cities and on air bases.

NOTE: Survey respondents could choose up to two locations. Ninety-eight percent of them chose only one location; the remainder were assigned evenly between the two locations. Totals may not sum to 100 percent because of rounding.

Respondents were queried about their working conditions, and these varied across services. As Table 4.2 shows, more Army and Marine Corps personnel worked outdoors or in military vehicles than did Air Force or Navy personnel. Air Force personnel were much more likely to work in a building, warehouse, or air-conditioned tent.

NOTE: Fewer than 1 percent of the Air Force, Army, and Marine Corps respondents indicated working in a tent but could not remember whether it had a floor or air conditioning. Totals may not sum to 100 percent because respondents could choose more than one location.

Similar differences existed in sleeping location, as shown in Table 4.3. Almost half the Air Force personnel slept in air-conditioned tents, and most of the remainder slept in buildings designed for housing. In contrast, about half of the Army, Marine Corps, and Navy personnel slept in tents without air conditioning. Most of the remaining Army and Marine Corps personnel slept outdoors or in their vehicles, and most of the remaining Navy personnel slept in buildings used for housing.

NOTE: Two percent of the Air Force respondents who remembered an air-conditioned tent but not whether it had a floor are not included in the table. Also not included are fewer than 1 percent of the Air Force, Army, and Marine Corps respondents who remembered a tent without air conditioning but not whether it had a floor. The Navy total does not sum to 100 percent because of rounding.

As Table 4.4 shows, latrine arrangements differed by service in a similar fashion: the majority of Air Force personnel had inside latrines; in the other services, the majority had outside latrines.

NOTE: Totals may not sum to 100 percent because of rounding.

Eating conditions were of particular interest because of concerns about the exposure of food to pesticides. Table 4.5 shows that, as with the other conditions, the Air Force differed from the other services, with a larger percentage of Air Force personnel eating in buildings and air-conditioned tents. Also, a large fraction of personnel in the other services ate in locations not designated for eating. Undoubtedly, most of them were located with combat units away from mess halls, as the majority of those who said "some other place" indicated "outdoors," as shown in Table 4.6.

NOTE: Totals may not sum to 100 percent because of rounding.

NOTE: Totals may not sum to 100 percent because respondents could choose more than one answer.

VARIATIONS IN PESTICIDE USE

In Tables 4.7 and 4.8 we show the overall average odds of use for each pesticide form and the percentage difference in the odds by demographic category.[1] These tables indicate who was likely to use a particular form of a pesticide. The first line in each table is the "baseline" odds of use, and then the percentage change from that baseline by various demographic characteristics is listed in each column.[2] The baseline group varies by each form. For example, in Table 4.7, the baseline group for sprays is Army, Caucasian personnel who lived in a tent city in the winter. For powders, it is Army, male, Caucasian personnel who lived in tent cities. We used asterisks to indicate varying levels of statistical significance--more indicate greater statistical significance. A blank cell indicates that a particular demographic category was not significantly associated with use and therefore was not included in the model.

NOTES: The baseline group for a particular form is identified by B in the column. If use did not differ across a demographic, then all the entries for that demographic are blank in the table; thus, it would not be part of the baseline. See Appendix C for details of the modeling methodology.
***p value ² 0.01; **0.01 < p value ² 0.05; *0.05 < p value ² 0.1.

Tables 4.9 and 4.10 give, for each demographic category, the percentage difference from "baseline" average use, as measured by the number of times used per month for each pesticide form. Combining Tables 4.7 and 4.8 with Tables 4.9 and 4.10, we get a picture of who was more or less likely to use various pesticide forms and, among those who used each form, who used them with greater or lesser frequency. As we discuss below, there are significant differences in both likelihood and frequency of use.

NOTES: The baseline group for a particular form is identified by B in the column. If use did not differ across a demographic, then all the entries for that demographic are blank in the table; thus, it would not be part of the baseline. See Appendix C for details of the modeling methodology.
***p value ² 0.01; **0.01 < p value ² 0.05; *0.05 < p value ² 0.1.

NOTES: The baseline group for a particular form is identified by B in the column. If use did not differ across a demographic, then all the entries for that demographic are blank in the table; thus, it would not be part of the baseline. See Appendix C for details of the modeling methodology.
***p value ² 0.01; **0.01 < p value ² 0.05; *0.05 < p value ² 0.1.

NOTES: The baseline group for a particular form is identified by B in the column. If use did not differ across a demographic, then all the entries for that demographic are blank in the table; thus, it would not be part of the baseline. See Appendix C for details of the modeling methodology.
***p value ² 0.01; **0.01 < p value ² 0.05; *0.05 < p value ² 0.1.

Service Similarities and Differences

These differences in living conditions are consistent with the differences between services in the types of pests veterans reported (see Table 3.1). They are also consistent with the variations in pesticide use shown in Tables 4.7 to 4.10.

Overall, Air Force personnel were less likely to use all forms of personal pesticides, and those who used a particular form of pesticide often used the pesticide less frequently. Marine Corps/Navy personnel were also less likely to use personal sprays, powders, and lotions than Army personnel, although those who used powders used them with much greater frequency than their Army counterparts.

Similarly, Air Force personnel were less likely to use or observe the use of powders and liquids, and those who used powders used them less frequently. One difference in this pattern is that Air Force personnel were more likely to use or observe "other" field sprays, although again with less frequency. In contrast to the use of personal pesticides, Marine Corps/Navy use of field pesticides was more like the Air Force than the Army.

Seasonal Differences

Demographic Differences

Under the assumption that field-use pesticides were applied equally across the enlisted ranks, we interpret the senior enlisted responses to be more indicative of the actual application of pesticides, as senior enlisted personnel would be more generally aware of such activities. We hypothesized that senior enlisted personnel would be the most likely to have observed field use, so their reports may be a better measure of actual field use. From this, we conclude that the overall percentage of personnel who used or observed the use of field aerosols, other sprays, and No-Pest strips is likely underestimated in the survey.

Reservists. We also compared reservists[3] to active duty personnel in our analyses, although this information is not shown in Tables 4.7 to 4.10. We found no differences in either prevalence or frequency of use using the standard statistical significance level of 0.05. However, we did find evidence that flea or tick collars were more widely worn by reservists: The odds of a reservist wearing a flea or tick collar was 122 percent greater than the odds for active duty personnel (p = 0.067). In addition, we estimated that reservists who wore flea or tick collars wore them 40 percent more than their active duty counterparts, although the estimate is statistically insignificant (p = 0.20).

However, the estimated differences between reservists and active duty personnel in other forms of pesticide and prevalence of use were small. For example, the next largest result, in terms of increased use, was for personal powders. We estimated that reservists were about 50 percent more likely to use personal powders (p = 0.25) with about a 44 percent increase in frequency of use (p = 0.17). For all other forms, reservists' use was essentially equivalent to or less than that of active duty personnel. Thus, even without considering statistical significance, no pesticide forms other than flea collars showed evidence of a large differences in either frequency of use or prevalence of use between the two groups.

Gender. We found few differences by gender. Females were less likely to use personal pesticides of a liquid or powder form, and they used lotions less frequently than their male counterparts.

Race. The most consistent demographic showing differential pesticide usage is race. In particular, African-American personnel were more likely to use sprays, powders, and lotions, and more often than their Caucasian counterparts.[4] They were also less likely to use personal liquids and wore flea or tick collars less frequently. "Other" races were also more likely to use lotions and wore flea or tick collars less frequently. Racial differences extended to field-use pesticides, in which African-American personnel were more likely to use or observe the use of field powders, aerosols, and other sprays. We do not have a satisfactory explanation for the differential reporting of field-use pesticides by race.

Food Service Occupational Differences

We found that food service personnel indicated a higher use of field pesticides. In particular, they were more likely to use or observe the use of "other" sprays; approximately twice as likely to use or observe the use of powders and pellets, granules, and crystals; and almost three times as likely to use or observe the use of liquids. They also reported that No-Pest strips were used or observed at slightly more than twice the baseline density--so that the No-Pest strips were hung on average at the recommended density--and "other" sprays were used with less frequency.

We found fewer differences between food service and other personnel in use of personal pesticides. Food service personnel used sprays, powders, and flea collars roughly 50 percent more often than their non-food service counterparts.

Differences by Living Arrangements

Estimates of use of field pesticides were also consistent. Personnel not living in buildings used or observed the use of pellets, powders, and granules more frequently, and they used or observed the use of aerosols less frequently. Personnel living in buildings used or observed the use of No-Pest strips much more frequently; so did personnel living in the desert. Personnel in the desert were also less likely to use or observe the use of other sprays.

SUMMARY

We found some differences in pesticide use by living arrangements; these are consistent with our expectations of how pesticides would be employed. We also found differences by race, although we cannot explain the differential reporting of use of field pesticides. And, although we found some differences in use of field pesticides by rank, we conclude that the differences probably result because senior personnel are in a position to be more aware of their use, though some of the difference may also be due to differences in living arrangements.

We found few seasonal differences in the use of pesticides. Where there were detectable differences, the pesticides were less widely used in the winter, but there was no difference in the frequency of use among those who used them. The only type of pesticide that showed a change in the frequency of use was flea or tick collars; they were worn less frequently in the summer. We also tested for whether there were statistically significant differences between those who used pesticides and those who did not by season and found the differences insignificant (p = 0.37). Furthermore, for pesticide forms that were not statistically significant, the estimated differences between summer and winter use and prevalence were small to modest. That is, none of the statistically insignificant results showed evidence of a large seasonal difference in either frequency of use or prevalence of use for that pesticide form.

[1]The odds are defined as the probability that an individual with a particular set of characteristics will use the pesticide form divided by the probability that he or she will not. The odds can be any number between zero and infinity. An odds of one means that the person is equally likely to use it as not. Odds of less than one means that the person is less likely to use the pesticide form, and an odds greater than one means that the person is more likely to use it.

[2]Odds are used, rather than probabilities, because it is easy to calculate the change in odds for any individual from the table. For example, in Table 4.7, the baseline individual has an odds of using sprays of 0.79. The odds for an equivalent Air Force person is simply 0.79 x (1 - 0.34) = 0.52. That is, it is just the percentage change times the baseline odds. This works for changes in multiple characteristics. For example, the odds for an Air Force person living in a building is 0.79 x (1 - 0.34) x (1 - 0.32) = 0.35.

[3]That is, personnel in the Reserves or National Guard during ODS/DS, as defined in the USASCURR Gulf War database.

[4]It is possible for insects to respond to visual cues. If present during ODS/DS, these insects may have been more likely to target dark-skinned personnel, which could have resulted in increased pesticide use. This would not explain the differential reporting of field-use pesticides, however.