Water pollution and childhood leukaemia risk: a systematic review

Water pollution represents a major global health concern, especially in low- and middle-income countries where toxic metals (TMs) and pesticides can contaminate drinking water through industrial, agricultural and urban activities. Children are particularly susceptible due to their developing physiology and higher water intake relative to body weight. This review aims to explore the association between exposure to TMs and pesticides in drinking water and the risk of childhood leukaemia (CL), highlighting the broader significance for environmental health and child safety. A structured search in PubMed, Scopus and Google Scholar (2001-2024) identified studies on acute lymphoblastic leukaemia or acute myeloid leukaemia in individuals under 20 years of age, assessing exposure to trace metals or pesticides via drinking water. Observational designs were included, excluding studies unrelated to water exposure or lacking paediatric data. Records were screened and reviewed independently by four authors. Findings were heterogeneous, with several studies suggesting potential links between specific contaminants like arsenic, hexavalent chromium, pentachlorophenol and certain pesticides and an increased risk of leukaemia in children, while others found no significant associations and noted methodological challenges such as small sample sizes and difficulties in exposure measurement. Although current evidence remains inconclusive regarding a direct causal relationship, this review underscores the need for rigorous, long-term research to clarify the role of waterborne pollutants in CL and to guide public health strategies.