UC Berkeley

Childhood lead poisoning is a multifactorial problem that affects as many as 500,000 US children younger than six years of age in the US. Drinking water is currently a major source of exposure: lead leaching from lead-based water infrastructure affects over 5,000 public drinking water utilities, potentially exposing over 18 million people to elevated lead water levels. Pipe replacement, the most effective solution to this problem, is prohibitively expensive, while chemical conditioning of drinking water using orthophosphates, although cost-effective, does not quickly solve the problem. Moreover, identifying the locations at risk of lead leaching is challenging because lead is not routinely measured, and when it is, the data are seldom made public. Thus, cost-effective technologies meant to detect and to stop lead leaching are currently needed to prevent childhood lead exposure and to enable an equitable and fair access to safe drinking water.The purpose of this dissertation is to develop the foundations of novel technologies meant to both identify the risk and prevent childhood lead exposure from drinking water, particularly in low-income settings where this problem is more prevalent. Chapter 1 presents an overview of the lead leaching problem in the US, its causes, and the health effects of childhood lead exposure. Chapter 2 presents a novel method for estimating the likelihood of lead leaching into the drinking water in schools at the state level using machine learning and applies this approach using data from the states of California and Massachusetts. Chapter 3 utilizes the same tools presented in chapter 2, but for predicting the risk of childhood lead poisoning at the state level. This model is tested and validated using lead blood data from the states of New York and Massachusetts. Chapter 4 introduces the foundations of a novel electrochemical method to prevent lead leaching into the drinking water from lead water pipes that overcomes some of the limitations of existing technologies. In this method, an external power supply is used to promote the formation of an insoluble scale within lead pipes that significantly decrease lead leaching rates. Chapter 5 presents a modified version of the method presented in chapter 4, in which an amorphous aluminum oxide layer is deposited within lead pipes. This method was tested in used lead pipes collected from a water distribution system and using different water matrices. Chapter 6 concludes this dissertation by discussing the implications of the main findings and by presenting recommendations for future work.