Lead exposure and visual-motor abilities in children from Chennai, India
Kavitha Palaniappan1, Ananya Roy, Kalpana Balakrishnan
1Department of Environmental Health and Engineering, Sri Ramachandra Medical College and Research Institute, Chennai, India.
Insights
High blood lead levels in Indian children are linked to impaired visual-motor skills. This study highlights the environmental hazard of lead exposure and its impact on child development, particularly fine motor functioning.
Area of Science:
- Environmental Health
- Developmental Pediatrics
- Neuroscience
Background:
- Lead exposure is a significant environmental health concern in India.
- Limited data exists on the effects of lead exposure on visuo-motor development in Indian children.
Purpose of the Study:
- To investigate the association between blood lead levels (BLLs) and visuo-motor, visual-spatial, and fine motor functioning in Indian children.
- To test the hypothesis that higher BLLs correlate with poorer motor skills.
Main Methods:
- Cross-sectional study of 814 Indian school children aged 3-7 years.
- Blood lead levels measured using LeadCare Analyzer.
- Visual-motor abilities assessed using the Wide Range of Visual Motor Abilities Test (WRAVMA).
Main Results:
- Mean BLL was 11.4±5.3 microg/dL.
- Multivariate analyses revealed an inverse relationship between BLLs and WRAVMA scores, adjusting for socioeconomic and demographic factors.
- A 10 microg/dL increase in BLL was associated with significant decreases in Visual Motor Composite and Drawing subtest scores.
Conclusions:
- Elevated blood lead levels in urban Indian children are associated with reduced visual-motor abilities, especially visual-motor integration.
- Findings suggest a dose-response relationship, with steeper declines in skills at higher BLLs.
- Highlights the neurodevelopmental impact of environmental lead exposure in a vulnerable population.
Abstract:
Lead exposure poses a major environmental hazard in India, but little information is available on the impact of lead exposure on visuo-motor development in Indian children. We hypothesize that higher blood lead levels are associated with poorer visual-motor, visual-spatial and fine motor functioning among children. We conducted a cross-sectional study of 814 school children, aged 3-7 years. Lead in whole blood was measured using the LeadCare Analyzer. The Wide Range of Visual Motor Abilities Test (WRAVMA) was administered to each child by trained examiners. The mean blood lead level was 11.4±5.3 microg/dL. In multivariate analyses adjusting for mother's education level, father's education level, average monthly income, hemoglobin and sex, WRAVMA scores were inversely related to blood lead level. An increase of 10 microg/dL was associated with a decrease of 2.6 points (95% CI: -4.5 to -0.7, P=0.006) in the Visual Motor Composite score and a decrease of 2.9 points (95% CI: -5.1 to -0.7, P=0.011) in the Drawing subtest. Exploration of the shape of the dose-effect relationships using spline functions indicated some non-linearities, with the steepest declines in visual-motor skills occurring at higher blood lead levels. Among urban Indian children, higher blood lead levels are associated with decreased visual-motor abilities, particularly visual-motor integration.
