Attention Deficit Hyperactivity Disorder (ADHD) affects an estimated 6% of school children in Catalonia, characterized by symptoms such as impulsivity and difficulty concentrating. While genetics are the primary cause, environmental factors, such as exposure to contaminants, can intensify symptoms, according to research led by the Universitat Rovira i Virgili (URV).
“"These factors influence brain development starting from pregnancy and throughout the child's first years of life."
The team focused on heavy metals—including copper, lead, mercury, cadmium, arsenic, and antimony—known to accumulate in critical brain areas like the hippocampus and frontal cortex. The study analyzed urine samples from 205 children aged 6 to 16, diagnosed using the international DSM5 criteria. The analysis was conducted by a specialized laboratory at the University of Granada.
The results showed a strong correlation: ADHD prevalence was five times higher in children with the highest lead levels compared to those with the lowest. This relationship was even more pronounced with copper, where children with the highest levels were sixteen times more likely to be diagnosed. Furthermore, exposure to mercury was linked to increased inattention and inconsistency in reaction times during cognitive tests.
“"Although the study does not prove that heavy metals directly cause ADHD, its results reinforce the evidence that reducing exposure to these elements would favor healthy brain development."
Co-author Sharanpreet Kaur noted that children already diagnosed with ADHD appeared more vulnerable, showing more intense negative effects even at similar exposure levels. The URV researchers, who collaborated with the CRAMC, stress the need for reinforced public health measures, including environmental surveillance, reduction of industrial emissions, and food safety, given the common presence of these metals in the environment.
