Impact of - IDL-BNC @ IDRC - International Development Research ...

In a pilot study, we found that the prevalence rate of pesticide use in the area
was 75%; c was set at 0.05 and z (from tables) at 1.96 for a probability of 5% in
a two-tailed test. Therefore:
n = (1.96)2(0.75)(0.25)/0.0025 or 288
Data were collected using interviewing techniques with the aid of a questionnaire.
Locally hired and trained research assistants visited each household in
the selected villages daily from September 1987 to December 1987 under the
supervision of the two principal investigators.
All questionnaires were in English, but, during the interview, they were
interpreted in Kikuyu. Attempts were made to interview the head of the
household. In his absence, the wife or an adult member of the household over
15 years of age was interviewed. Agrochemicals (mainly pesticides) were
collected from every sixth household if available.
Results
During data collection, 1 797 households were surveyed by interview and 99
unknown agrochemical samples were randomly collected. To establish
authenticity, these were qualitatively analyzed in the laboratory using gas
chromatography. Among the 99 samples, only 21 pesticides were identified
because of duplication, a situation that could not be established in the field.
The most commonly used chemicals in the community were fertilizer, fungicides,
insecticides, herbicides, nematicides, and rodenticides.
All households reported that they were currently using agrochemicals or had
used them within the preceding 6 months (Table 2). The frequency of use
ranged from continuously throughout the year to every crop season.
Members of the community other than farmers were also exposed to agrochemicals
at a high level, e.g., coffee factory workers, career spray operators,
and women who sold agrochemicals in the open markets. Career spray
operators are young professionals who go from farm to farm, spraying coffee
crops on a contract basis. During the peak of the spraying season, they
sometimes work many hours every day of the week.
Frequency
Table 2. Frequency of use of fertilizers and pesticides.
110
Number of
respondents %
All year 922 51.9
Every crop season 840 46.7
Irregular 24 1.3
Total 1 797 99.9