Institutionen för folkhälsovetenskap / Department of Public Health Sciences
Abstract
Background: Acute pesticide poisonings (APP) are a public health problem
in Nicaragua. The quality and coverage of APP´s register, the real
incidence of APP, the main determinants, the economic cost of treating
cases and the effectiveness of educational intervention are not well
known.
Aim: The overall aim was to investigate the acute health impact of
pesticide use and to discuss the possible effectiveness of preventive
measures in Nicaragua. The specific aims were to calculate the proportion
of APP cases officially registered, to estimate one year cumulative
incidence of APP cases among population 15 years and older, to identify
the main determinants related to APP among pesticide sprayers and to
evaluate the impact of an integrated pest management (IPM) training
intervention.
Methods: For studies 1, 2, and 3, data concerning pesticide exposure and
health effects were assessed in a nationally representative survey of
3169 persons 15 years and older in year 2000. For study 1, to estimate
the proportion of underreporting of APP cases, the cases reported at the
official surveillance system were cross matched with the casesreported
through the survey. In study 2, based on self reported cases we estimated
the one year incidence rate and the number of expected cases of APP in
the country. In study 3, after regression analysis, the main determinants
for APP among agricultural sprayers were identified. Study 4 assessed the
impact of a 2 years IPM training to reduce economic costs and acute
adverse health effects among 1200 basic grain farmers comparing the group
of trained farmers and a group of "control" farmers who did not receive
training.
Results: Less than 5% of medically treated APP cases were reported to the
official register. The one year APP incidence among general population
was 2.3% (95%CI 1.7-2.8). The rate was higher among men, rural population
and agricultural workers. More than 66,000 cases were estimated to occur
yearly. The national incidence rate of APP among sprayers was extremely
high, 8.3% (95% CI 5.8-10.8) and more than 34,000 cases were estimated to
occur among pesticide sprayers, and representing 52% of all APP s
estimated in year 2000. Although most of the cases were minor and
moderate, the poisonings caused near 340,000 disability days. The causal
agents for APP in 95% of cases were WHO Class I-II pesticides. The main
determinants of APP among sprayers were: backpack pump leakage and
incomplete or no use of personal protective equipment. Seventy seven
percent of cases were caused by pesticides proposed to be banned or
restricted in Central America. The IPM training prevented acute health
effects and maintained productivity: after two years of training, the
trained farmers used fewer pesticides, spent less money on pest control,
made higher net returns, and suffered less exposure to
cholinesterase-inhibiting pesticides compared to farmers who did not
receive IPM training.
Conclusion: Underreport figures leads to an erroneous interpretation of
acute pesticide health effects. There is a high APP incidence rate in the
general population, but it is four times higher among sprayers, causing
important loss of or productivity and important economic costs. IPM
interventions were successful in prevent the occurrence of APP cases and
economic losses. Traditional prevention and control measures are
insufficient and structural changes, including pesticides banning and
restriction, and change to IPM agriculture models, are needed to
transform the underlying determinants