Effect of community of residence on neurobehavioral development in infants and young children in a flower-growing region of Ecuador

Abstract

Objective: In this study we compared neurobehavioral development in Ecuadoran children living in two communities with high potential for exposure to organophosphate (OP) and carbamate pesticides to that of children living in a community with low potential for exposure.

Methods: Women residing in the study communities who had a child 3-61 months of age completed a questionnaire about maternal and child health and sociodemographic characteristics. The Ages and Stages Questionnaire (ASQ) was administered to each child (n = 283). Growth measurements and a hemoglobin finger-prick blood test were obtained. We used multiple linear regressions to evaluate associations between community of residence and delayed development, adjusting for child health status and other characteristics of the home environment.

Results: Children 3-23 months of age who resided in high-exposure communities scored lower on gross motor (p = 0.002), fine motor (p = 0.06), and socioindividual (p-value = 0.02) skills, compared with children in the low-exposure community. The effect of residence in a high-exposure community on gross motor skill development was greater for stunted children compared with non-stunted children (p = < 0.001) in the same age group of 3-23 months. Children 24-61 months of age residing in the high-exposure communities scored significantly lower on gross motor skills compared with children of similar ages residing in the low-exposure community (p = 0.06).

Conclusions: Residence in communities with high potential for exposure to OP and carbamate pesticides was associated with poorer neurobehavioral development of the child even after controlling for major determinants of delayed development. Malnourished populations may be particularly vulnerable to neurobehavioral effects of pesticide exposure.

Figure 1

Unadjusted means of the five ASQ developmental domains by community of residence for children 3–23 months of age (n = 121). (A) Communication (p = 0.28), (B) Gross motor (p = 0.02), (C) Fine motor (p = 0.25), (D) Resolution of Problems (p = 0.49), and (E) Socioindividual (p = 0.05). The dashed line indicates the mean score for each community and the corresponding mean value is displayed to the left of the dashed line. The solid line indicates the median score for each community. Pairwise t-tests were used to assess the mean difference in ASQ score between community comparison groups.

Figure 2

Unadjusted means of the five ASQ developmental domains by community of residence for children 23–61 months of age (n = 142). (A) Communication (p = 0.48), (B) Gross motor (p = 0.09), (C) Fine motor (p = 0.05), (D) Resolution of Problems (p = 0.01), and (E) Socioindividual (p = 0.74). The dashed line indicates the mean score for each community and the corresponding mean value is displayed to the left of the dashed line. The solid line indicates the median score for each community. Pairwise t-tests were used to assess the mean difference in ASQ score between community comparison groups.

Figure 3

Percentage of children displaying developmental delay for the five ASQ developmental domains, stratified by community of residence for children 3–23 months of age (n = 123).

Figure 4

Percentage of children displaying developmental delay for the five ASQ developmental domains, stratified by community of residence for children 24–61 months of age (n = 160).