Sumario: |
Mancozeb and maneb belong to a class of fungicides that are widely used in agriculture
world-wide. In Costa Rican banana plantations, these fungicides are sprayed on banana
plantations via light aircraft. Animal toxicity studies suggest that maneb and mancozeb can be
carcinogenic but there are few human studies on exposure or health effects. The main
metabolite of these fungicides is ethylenethiourea (ETU), which has also been shown to be
carcinogenic in animals and has the potential to adversely affect thyroid function in humans.
Physiological and behavioral reasons make children more vulnerable to pesticide exposures.
The aim of this study was to examine the relationship between child time activity patterns and
levels of urinary ETU in children that live on banana plantations sprayed with mancozeb and
maneb in Costa Rica.
Children in the study (n = 37) were recruited from a small banana plantation community
in the Caribbean coast of Costa Rica. Urine samples (first morning void) were collected once
daily for 7 days and children were also asked to complete a visual time activity diary for each of
the 7 days. The time activity diary was a 4 inch x 6 inch card with pictures that the children wore
around their necks during the day. It was pilot tested for one week and changes were made
according to the children‟s reactions in preparation for the final study. The urine samples were
frozen and mailed to Lund University in Sweden where they were analyzed for ETU levels in µg
ETU/g creatinine, or µg/L ETU adjusted for density.
Compared to levels of ETU reported in other studies, we found that children living in the
banana plantation are highly exposed to ETU but this varies according to their activity patterns
and whether aerial spraying occurred or not. For example, active children in this population had
on average have 1.7 times higher levels of ETU in their morning urine after spraying days as
compared to days where spraying did not occur. There is evidence to suggest that children
have higher levels of ETU in their urine after spraying days if they spent 7 or more hours being
active and outside.
Implementation of the time activity diary was possible with this particular group of
children but the accuracy of the responses should be validated with external observations of the
children. The validation through external observations verifies the responses recorded by the
children and is an important step when working with new groups of children.
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