Chapter 1 - The importance of chemical toxicants in Water, Sanitation, and Hygiene (WASH) provision

1.5 Chapter summary, 1.6 References

Video message from the former Director of US National Institute of Environmental Health Sciences, Dr. Linda Birnbaum, at the inaugural meeting of the WASH-Toxics Working Group, October 2016.

Summarizing Chapter 1:

  • Globalization has led to widespread chemical pollution in developing countries. Exposure to many of these chemical substances causes deleterious effects on the immune system, impairing the body’s response to infectious diseases and reducing the effectiveness of vaccinations and WASH interventions[18].

  • Environmental scientists, engineers, and toxicologists have long worried about the damaging impacts of chemical pollutants on the environment and human health. However, so far WASH development has neglected this critical topic[5].

  • Recent research has indicated that mitigating chemical exposures is a necessary-but-insufficient condition for achieving transformational WASH outcomes[18, 28].

The purpose of this book is to provide WASH practitioners, and really anyone whose responsibility is the safety of drinking water in their household or community, with the relevant background on the importance and treatability of chemicals in low-resource settings. Adsorption processes provide the currently best available, cost-effective means for controlling many chemical pollutants in water. Biochar adsorbent is a material that can be made locally using very simple and inexpensive technology for use in water treatment. The chapters that follow provide the necessary minimum technical knowledge of adsorption processes, along with practical tools for making biochar adsorbent, integrating biochar treatment for chemical pollutants with other unit processes that remove or inactivate biological pathogens, and the design, operation, and monitoring of biochar water treatment systems in low-resource settings.

This book represents the culmination of nearly fifteen years of field and laboratory research by myself and many cherished colleagues. Our research continues to improve biochar water treatment and extend it into new domains. However, the time is ripe to translate our results from “academicspeak” published in peer-reviewed journals into an accessible, actionable field manual. I aim to provide in these pages a compendium of best-practices for implementing biochar water treatment that are based on the current state-of-the-art. My hope – our hope – is to highlight a historically neglected component of WASH programming, and provide a “shovel-ready” solution on the path to achieving transformational WASH for all.

1.6 Chapter 1 References

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[Next up: Chapter 2 - ‘Priority pollutants’ and chemicals of emerging concern]