Graduation Year

2022

Document Type

Dissertation

Degree

Ph.D.

Degree Name

Doctor of Philosophy (Ph.D.)

Degree Granting Department

Civil and Environmental Engineering

Major Professor

James R. Mihelcic, Ph.D.

Co-Major Professor

Mahmooda Khaliq Pasha, Ph.D.

Committee Member

Jeffrey A. Cunningham, Ph.D.

Committee Member

Katherine Alfredo, Ph.D.

Committee Member

Norma Alcantar, Ph.D.

Keywords

Blood Lead Level, Environmental Risk, Social Marketing, Sub-Saharan Africa, Sustainable Development Goals

Abstract

The World Health Organization (WHO) has consistently listed lead (Pb) as one of the ten chemicals of major public health concern. Though the toxic nature of lead has been known since the 20th century it is still utilized in a wide variety of products due to its favorable properties. Exposure to lead still accounts for approximately 900,000 deaths annually and disproportionately impacts those in low- and middle-income countries (LMIC) due to a variety of reasons such as poverty, malnutrition, and lack of knowledge on the toxic nature of lead. Lead exposure routes include air, soil, dust, diet, and water. Though aqueous lead exposure is a primary exposure route examined in high income countries there is limited information about this exposure route in LMICs. In turn, the aim of this study is to demonstrate that improved health is possible by reducing exposure to lead contaminated water by way of a case study in Toamasina, Madagascar. Toamasina is a coastal city where centralized piped water is not always affordable or reliably available, creating a demand for a supplemental decentralized self-supply water system which frequently takes the form of a pitcher pump that serves an individual or small group of households. These pumps are traditionally manufactured with leaded components that pose a range of health risks to those using the water for drinking and cooking. Complexities arise from the unique market for hand-driven wells, cultural norms, and the lack of understanding of the health effects of lead on locals. An engineered solution to retrofit the pumps with non-leaded components was identified by previous researchers, but previous adoption of the engineered solution was limited.

In total, this research remediated over 1,000 pumps, tested aqueous lead levels in over 600 pumps, modeled blood lead levels (BLLs) and economic impact, tested BLLs in more than 300 children, and developed and implemented a social marketing campaign geared towards pump technicians. Statistically significant decreases in aqueous lead levels were observed in both the 2018 (Z = -11, ρ < .0001) and 2020 (t(35)= 3.78, p < 0.001; 95% CI[6.75,22.42]) remediations. A return-on-investment (ROI) of greater than 1000-to-1 was estimated based on the 2018 remediation. However, comparison of measured and modeled BLLs showed the IEUBK model highly underpredicted BLLs, indicating that the projected ROI is likely a conservative estimate. With no correlation seen between aqueous lead and change in BLL it is likely there is a variable impacting BLLs that is not being accounted for. Nevertheless, measured BLLs were observed to have a statistically significant decrease (t(54)= 6.15, p < 0.001; 95% CI[2.81,5.52]). Evaluation from the social marketing campaign showed an increased adoption of lead-free practices. Findings also indicate a need for future research efforts focusing on increasing awareness among the Toamasina residents and pump owners.

Utilizing a convergent research approach, this dissertation integrates engineering, social marketing, and public health to demonstrate how improved global health can be achieved. This dissertation presents methodology that can be utilized in other geographic locations and adapted to examine other exposure routes/sources. Results presented indicate the importance that aqueous lead exposure can have in LMICs, the impact that small scale remediations can have on reducing exposure and protecting public health, and the need for interdisciplinary approaches to sustainably address global challenges.

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