Nearly 60,000 Connecticut children under age 6 were reported with lead exposure in 2013, and an additional 2,275 children had high enough levels of the toxin in their blood to be considered poisoned. While those numbers, the latest available from the state Department of Public Health, may seem high, health experts say they actually must be higher because of significant gaps in state-mandated testing. Even though Connecticut has some of the strictest lead-screening laws in the country – requiring every child to be tested twice, before age 3 – DPH figures show that only half were screened twice, as mandated. Unlike in Flint, Mich., whose residents were poisoned when a corrosive water source was directed through aging lead-lined pipes, the main culprit in Connecticut is lead paint. Though banned in 1978, lead-based paint is present in countless older apartment buildings and homes, especially in urban centers, such as Hartford, New Haven and Bridgeport.