Researchers report that higher concentrations of lead in childhood blood were linked to more depressive symptoms in adolescence. They found that each doubling in mean childhood blood lead concentrations was associated with an increased risk of elevated child-reported depressive symptoms. Low childhood lead levels were also linked to self-reported depressive symptoms later in childhood. The increase in risk was particularly large when exposures occurred in late childhood and early adolescence.
The team analyzed data from 218 caregiver–child pairs enrolled in the Health Outcomes and Measures of Environment Study, which followed families from the second trimester of pregnancy to age 12. Blood lead was measured at ages 1, 2, 3, 4, 5, 8, and 12, and anxiety and depression were assessed around age 12.
Study author Christian Hoover said the results suggest lead exposure throughout childhood is associated with depressive symptoms and that age 8 appeared to be a consequential time. The authors noted the need to prevent and reduce lead exposure in children.
Difficult words
- concentration — amount of a substance in a given volumeconcentrations
- depressive symptoms — signs of sadness, low energy, or low mood
- adolescence — the period between childhood and adulthood
- doubling — an increase to two times the previous amount
- exposure — contact with something harmful or dangerous
- enroll — officially joined a study or programenrolled
- consequential — important because it causes later effects
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Discussion questions
- Why do you think late childhood and early adolescence might be a sensitive time for lead effects on mood?
- What steps could communities take to prevent and reduce lead exposure in children?
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