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Trihalomethanes in developed and developing countries
Anjali Kothe1, Neha Wachasunder1, Anupama Rodge1
1Water Technology and Management Division, CSIR-National Environmental Engineering Research Institute, Nehru Marg, Nagpur, 440 020, India.
Environmental Monitoring and Assessment
|December 6, 2023
Summary
Disinfection by-products like trihalomethanes (THMs) form in drinking water. Developed nations reduced THMs, but developing countries need to lower high concentrations for public health.
Area of Science:
- Environmental Chemistry
- Public Health
- Water Treatment
Background:
- Disinfection by-products (DBPs), including trihalomethanes (THMs), form from reactions involving natural organic matter, contaminants, and disinfectants during water treatment.
- THM formation is primarily linked to water chlorination processes.
Purpose of the Study:
- To compare trihalomethane (THM) concentrations in drinking water across twenty developed and developing countries.
- To evaluate the effectiveness of different water disinfection techniques in relation to THM levels.
Main Methods:
- Comparative analysis of THM concentrations reported in literature from 11 developed and 9 developing countries.
- Review of water disinfection techniques employed in these nations.
Main Results:
- THM concentrations varied widely, from 0.5 µg/L (Germany) to 215 µg/L (Russia) in developed countries, and 3 µg/L (China) to 439.2 µg/L (Bangladesh) in developing countries.
- Developed countries showed partial success in reducing THM levels, while developing countries require significant improvements.
- Water source characteristics, quality, environmental factors, and treatment technology efficiency influence THM concentrations.
Conclusions:
- Significant disparities in THM levels exist between developed and developing nations, highlighting the need for targeted interventions.
- Adherence to and continuous monitoring of DBP guidelines are crucial for managing THM concentrations.
- Preventative strategies, such as precursor removal and integrated advanced water treatment technologies, are essential for minimizing THM formation and protecting public health from carcinogenic DBPs.
Keywords:
Developed and Developing CountriesDisinfection by-products (DBPs)Factors affecting THM formationGuidelines for DBPsRisk assessmentTrihalomethanes (THMs)More Related Videos
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