Introduction: River water pollution has been a significant hazard to human health and is associated with severe health risks. This study evaluates water quality and heavy metal levels in the Klang River, analyzing their health risks through chemometric analysis. Methods: Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) was used to analyse the heavy metal contents in river water samples obtained from 9 sampling stations. Chemometric statistical techniques (principal component analysis (PCA) and hierarchical cluster analysis (HCA)) are employed to identify the sources of physicochemical properties and heavy metals. The human health risk was evaluated using statistical analysis, apart from hazard quotient (HQ), hazard index (HI), and carcinogenic risk (CR). Results and Discussion: Results showed that the physicochemical parameters were within acceptable limits. The concentration of heavy metals was found to follow a decreasing order of As > Ni below permissible levels, except at P9 and P8. PCA and HCA showed important connections among parameters, emphasizing that COD, NH3N, and TDS are key factors affecting Klang River water quality. Conclusion: The study assesses pollution risks in the Klang River, offering crucial insights for sustainable estuary management. It highlights significant changes in temperature, pH, TDS, BOD, DO, and NH3N levels, along with specific trends in heavy metal concentrations. The Health Risk Assessment indicates acceptable HQ and Target Cancer Risk values. However, the study's limited sample sites and focused timeframe might hinder understanding long-term patterns and regional differences. Extended data collection and additional information are necessary to improve water quality management and protect public health

In Malaysia, 43%-70% of household wastewater is greywater, with characteristics influenced by lifestyle, fixtures, and weather. It is often discharged untreated, posing environmental and health risks. This study assessed the knowledge, attitudes, practices, and key factors influencing greywater management among rural residents in Perak, Malaysia. A community-based cross-sectional survey was conducted from March to April 2023, involving 121 participants selected via the Linear Time Function sampling method. Data were analyzed using a structured questionnaire and Chi-square analysis, revealing a significant association between knowledge and attitudes toward greywater management, with higher awareness linked to more positive perceptions and willingness to adopt proper practices (p < 0.001). Additionally, individuals with better knowledge were more likely to engage in systematic greywater disposal methods, such as using septic tanks instead of direct discharge (p = 0.006). The findings provide valuable insights for policymakers and stakeholders in designing community-driven greywater management strategies that enhance public awareness, improve infrastructure, and support sustainable water resource management. Further research is recommended to investigate the underlying factors influencing community attitudes and behaviors toward greywater management, particularly the socio-cultural, economic, and perceptual barriers that contribute to the knowledge-to-practice gap in rural areas.

Environmental managers, scientists, and the general public have a widespread interest in ecological indicators. While indicators have long been used to detect changes in nature, the scientific maturation of the development of indicators has only occurred in recent decades. At present, indicators are primarily used to evaluate the state of the environment, as early warning indicators of ecological problems, and to monitor trends in ecological resources. The impoundment of rivers constitutes one of the most important anthropogenic impacts on rivers in the world. Over the past two decades, increasing numbers of studies have attempted to quantify the impacts of river impoundments on riverine ecosystems, often focusing on the impacts of individual large reservoirs. Most research in shallow streams involves benthic diatom assemblages, while research in deeper rivers focuses primarily on planktic diatoms. Diatom datasets are relatively scarce for assessing downstream effects of river impoundment. Without further evaluation, it is difficult to determine where our ecosystem has been damaged and polluted, resulting in negative effects on ecosystems such as structure and characteristics, as well as an impact on human health. <!----> <!----> <!----> <!---->