Water Chlorination topic

Water Chlorination topic. Water chlorination is viewed as one of the top public health developments in the last century, as seen in the gra…

Water Chlorination topic

Introduction

Water chlorination is viewed as one of the top public health developments in the last century, as seen in the graph below (CDC, 2012). Do you agree? Discuss some of the history of water chlorination and the benefits. What are some of the ongoing risks of water chlorination?

CDC. 2012. History of Drinking Water Treatment. https://www.cdc.gov/healthywater/drinking/history.html

Water Chlorination

Solution

            For over a century, water chlorination has been one of the most effective water disinfection and treatment methods. As the graph from CDC (2012) indicates, there has been a steady decrease in death from infectious diseases from 1900 to 1996 due to increased water treatment and disinfection efforts coupled with improvements in sanitation and hygiene and the quality of source water.

            I agree that water chlorination has been one of the first line defense mechanisms in treating water, especially in reducing most bacteria and viruses in water. However, chlorination approaches and agents have changed significantly since its first reported use in 1897.

For example, bleach was first used to disinfect the water main following a typhoid outbreak in Maidstone, Kent, UK. In the US, Jersey was the first to use chlorine to disinfect a water supply and develop the legal frameworks that support its use (International Agency for Research on Cancer, 1991).

Over the years, significant changes have been on transporting and storing liquid chlorine, making it accessible to many people and communities. Further, the advancements have helped reduce the taste and odor of chlorine in water and developed implementation frameworks such as the safe water system, which helps households self-treat the water.

            The success and widespread use of chlorination was linked to its effectiveness in reducing bacteria and viruses in the water. Hence, chlorination became the primary approach to preventing typhoid fever and cholera (CDC, 2020). Besides, water chlorination controls slime and algae growth in mains pipes and storage tanks and helps to remove unwanted nitrogen compounds from water (CDC, 2012).

            On the other hand, water chlorination increases the possibility of disinfection by-products (Betts, 1998). For instance, excess chlorine in water can combine with organic material in the water to form substances such as Trihalomethanes, which can cause liver, kidney, or central nervous system problems and are linked to an increased risk of cancer over a lifetime of exposure (International Agency for Research on Cancer, 1991).

Furthermore, chronic exposure to concentrations of chlorine of around 5 mg/l has been associated with respiratory complaints, corrosion of the teeth, inflammation of the mucous membranes of the nose, and increased susceptibility to tuberculosis (International Agency for Research on Cancer, 1991).

Some bacteria and viruses also seem resistant to chlorine, necessitating the use of alternative disinfectants. These risks associated with chronic exposure and disinfection by-products could be lead to health complications, making some communities that rely solely on chlorination highly susceptible.

References

Betts, K. (1998). Growing concern about disinfection by-products. Environmental science & technology, 32(23), 546A-548A.

CDC. (2012). History of Drinking Water Treatment. cdc.gov. Retrieved May 23, 2021, from https://www.cdc.gov/healthywater/drinking/history.html/.

CDC. (2020). Water Disinfection with Chlorine and Chloramine. cdc.gov. Retrieved May 23, 2021, from https://www.cdc.gov/healthywater/drinking/public/water_disinfection.html

IARC Working Group on the Evaluation of Carcinogenic Risks to Humans. Chlorinated Drinking Water; Chlorination by-Products; Some Other Halogenated Compounds; Cobalt and Cobalt Compounds. Lyon (FR): International Agency for Research on Cancer; 1991. (IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, No. 52.) Chlorinated drinking water. Available from: https://www.ncbi.nlm.nih.gov/books/NBK506911/