The report states that children are most vulnerable to mercury exposure, whether exposed in utero or as young children. Mercury affects the developing brain, causing neurological problems that manifest themselves as vision and hearing difficulties, delays in the development of motor skills and language acquisition, and later, lowered IQ points, problems with memory and attention deficits... The physical changes that occur in the developing brain due to mercury exposure during pregnancy are described along with how these changes later translate into learning difficulties in school. The report estimates the societal and economic impacts of mercury exposure in terms of the cost of special education in the U.S. and the societal benefits of reducing mercury emissions.