Assessing the Impact of Trihalomethanes in Drinking Water on Cancer Risk: А Literature Review

Abstract

Ensuring the safety of drinking water supply for the population is an important area of modern public health worldwide. In recent years, the risk of potential exposure to chemical compounds in water has increased, which may subsequently have a negative impact on human health in the long term. The aim of this review: to conduct a comparative analysis of international experience in assessing the carcinogenic risks associated with trihalomethanes in drinking water. Methods. The review was prepared based on the recommendations of PRISMA. We searched in databases, including Scopus, PubMed, and the WoS, to find scientific articles published from 2015 to 2025 for the following keywords. The selection process included identification, screening, compliance assessment, and inclusion steps. In total, 412 records were checked after the duplicates were removed, of which 298 were excluded, and 26 articles were selected for analysis. The selected publications were subjected to a thorough content analysis, thematic and comparative analysis, with particular attention to regional differences in impact assessment methodologies, regulatory frameworks and monitoring practices, where several thematic groups were identified: impact assessment methods, dose-effect relationship, and comparative analysis of the regulatory framework. Results. The analysis revealed several gaps in research that could affect the assessment of risks associated with exposure to disinfection products. There is still a need for longitudinal epidemiological studies with long follow-up periods to better characterize long-term risks such as carcinogenic. Epidemiological data from some countries in Central Asia and Eastern Europe remain limited, underscoring need for regional research initiatives and improved monitoring systems. Differences in regulatory standards, monitoring systems, and impact assessment methodologies lead to different approaches to risk management strategies. Conclusions. Effective risk reduction is achieved through improved water treatment technologies, the introduction of comprehensive monitoring programs and the integration of environmental and human health data. For Central Asian countries, including Kazakhstan, the development of standardized monitoring systems and the strengthening of environmental surveillance systems are important steps towards improving drinking water safety and reducing potential carcinogenic risks. Keywords: trihalomethanes, drinking water, environmental exposure, water pollutants, malignant neoplasms, carcinogenic risk.