Tap Water Lead Levels in Madrid (Spain): Degree of Compliance and Health Risk Assessment

Lead is one of few substances known to have a direct impact on health through the drinking water supply. Significant amounts of lead can be infiltrated in tap water as a result of leaching in distribution and plumbing system. This research was conducted to characterize Pb in tap water in the 21 districts of Madrid city over a long period of 12 years (2007–2018) and to assess the children health risks generated by the exposure to lead in the water supply. A total of 2308 first-flush water samples were collected from various types of buildings and analyzed for Pb using electrothermal atomic absorption spectroscopy. The sampling was carried out considering different factors: year, district and type of building. Tap water in most samples (96%) complied with the legislation throughout the study period. More cases of non-compliance were observed in 2014 because the impact of stricter regulations entry in force in December 2013 (10 μg/L). It was also significantly higher in the oldest districts located in the central area of Madrid and in households compared to other types of buildings ( p 1 and average loss of Intelligent quotient (IQ loss)