The policy of encouraging agriculture and development for mass tourism has led to environmental problems in Cameron Highlands, Malaysia. Rampant development and land clearing have significantly altered the land cover of Cameron Highlands for the past 30 years. Sensitive highlands areas are prone to landslides and soil erosion which then contributed to the main water pollution issues in the network of river system, sedimentation and siltation. The continuous trend of river water quality deterioration in Cameron Highlands has raised the issues for discussion in this review article. The purpose of this review is to briefly summarize the land use change, agriculture practices, agro-tourism, and agriculture policy and management toward water quality of the river system network in Cameron Highlands specifically in the downtown where most of the development and agriculture activities are concentrated. A rigorous review has been done on the existing literature to determine the relationship between land use change and agriculture practices toward river water quality in Cameron Highlands from 2001 to 2017. The total number of reviewed papers was 68. The outcomes established from previous researchers have highlighted factors such as soil erosion, landslides, agriculture activities, urbanization, and unplanned development associated with land use change have significantly influenced the river water quality in the highland areas. Continuous land use changes without proper development plan and law enforcement may critically threaten the sustainability of river network in the highlands area.

Indoor dust acts as a media for heavy metal deposition. Past studies have shown that heavy metal concentration in indoor dust is affected by local human activities and atmospheric transport can have harmful effects on human health. Additionally, children are more sensitive to heavy metals due to their hand-to-mouth behaviour and rapid body development. However, limited information on health risks were found in past dust studies as these studies aimed to identify heavy metal concentrations and sources of indoor dust. The objective of this review is to discuss heavy metal concentration and sources influencing its concentration in indoor dust. Accordingly, high lead (Pb) concentration (639.10 μg/g) has been reported in heavy traffic areas. In addition, this review paper aims to estimate the health risk to children from heavy metals in indoor dust via multiple exposure pathways using the health-risk assessment (HRA). Urban areas and industrial sites have revealed high heavy metal concentration in comparison to rural areas. Hazard index (HI) values found in arsenic (As), chromium (Cr) and Pb were 21.30, 1.10 and 2.40, respectively, indicate that non-carcinogenic elements are found in children. Furthermore, most of the past studies have found that carcinogenic risks for As, cadmium (Cd), Cr and Pb were below the acceptable total lifetime cancer risk (TLCR) range (1×10-6-1×10-4). The results of health risk assessment in this review show that carcinogenic risk exists among children. Hence, this proves that future studies need to focus on children's carcinogenic risk in indoor dust studies in order to find out the sources of heavy metals in indoor dust. This review highlights the importance of having the HRA application using bioavailable heavy metal concentration as it provides more accurate health-risk estimation. Moreover, this review is also useful as a reference for policy decision making in protecting children's health.

BackgroundThere is a lack of data describing the exposure of Malaysian schoolchildren to Secondhand Smoke (SHS). The aim of this study is to identify factors influencing schoolchildren's exposures to SHS in Malaysia.MethodThis cross-sectional study was carried out to measure salivary cotinine concentrations among 1064 schoolchildren (10-11 years) attending 24 schools in Malaysia following recent partial smoke-free restrictions. Parents completed questionnaires and schoolchildren provided saliva samples for cotinine assay.ResultsThe geometric mean (GM) salivary cotinine concentrations for 947 non-smoking schoolchildren stratified by household residents' smoking behaviour were: for children living with non-smoking parents 0.32 ng/ml (95% CI 0.28-0.37) (n = 446); for children living with a smoker father 0.65 ng/ml (95% CI 0.57-0.72) (n = 432); for children living with two smoking parents 1.12 ng/ml (95% CI 0.29-4.40) (n = 3); for children who live with an extended family member who smokes 0.62 ng/ml (95% CI 0.42-0.89) (n = 33) and for children living with two smokers (father and extended family member) 0.71 ng/ml (95% CI 0.40-0.97) (n = 44). Parental-reported SHS exposures showed poor agreement with children's self-reported SHS exposures. Multiple linear regression demonstrated that cotinine levels were positively associated with living with one or more smokers, urban residence, occupation of father (Armed forces), parental-reported exposure to SHS and education of the father (Diploma/Technical certificate).ConclusionsThis is the first study to characterise exposures to SHS using salivary cotinine concentrations among schoolchildren in Malaysia and also the first study documenting SHS exposure using salivary cotinine as a biomarker in a South-East Asian population of schoolchildren. Compared to other populations of similarly aged schoolchildren, Malaysian children have higher salivary cotinine concentrations. The partial nature of smoke-free restrictions in Malaysia is likely to contribute to these findings. Enforcement of existing legislation to reduce exposure in public place settings and interventions to reduce exposure at home, especially to implement effective home smoking restriction practices are required.

Adoption of smoke-free measures has been one of the central elements of tobacco control activity over the past 30 years. The past decade has seen an increasing number of countries and proportion of the global population covered by smoke-free policies to some extent. Despite reductions in global smoking prevalence, population growth means that the number of non-smokers exposed to the harms caused by secondhand smoke remains high. Smoke-free policy measures have been shown to be useful in protecting non-smokers from secondhand smoke, and can additionally increase cessation and reduce smoking initiation. Policies tend to be aimed primarily at enclosed public or workplace settings with very few countries attempting to control exposure in private or semiprivate spaces such as homes and cars, and, as a result, children may be benefiting less from smoke-free measures than adults. Compliance with legislation also varies by country and there is a need for education and empowerment together with guidance and changing social norms to help deliver the full benefits that smoke-free spaces can bring. Restrictions and policies on use of electronic cigarettes (e-cigarettes) in smoke-free settings require more research to determine the benefits and implications of bystanders’ exposure to secondhand e-cigarette aerosol, dual use and smoking cessation.

Abstract Background: It is estimated that pesticide production and use have increased continuously in the countries of Southeast Asia in recent years. Within the context of protecting the safety and health of workers in the agricultural sector, there is an existing gap in the implementation of the pesticide management framework because safety and health effects arising from occupational exposures continue to be reported. Objective: This study aims to provide narrative similarities, differences and weaknesses of the existing pesticide management system in Southeast Asian countries (Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand and Vietnam) within the context of occupational safety and health. Methods: This is preliminary traditional review study. Pesticide regulation and management at the country level were identified using web-based search engines such as Scopus, ScienceDirect, PubMed and Google. Book, reports, legislation document and other documents retrieved were also gathered from international organizations and specific websites of governmental agency in Southeast Asian countries. The scope of this review is only limited to literature written in English. In total, 44 review articles, reports and documents were gathered for this study. The approach of pesticide management in protecting safety and health in the agricultural setting were benchmarked according to the elements introduced by the United States Environmental Protection Agency, namely, (1) the protection of workers and (2) the practice of safety. Results: All countries have assigned a local authority and government organization to manage and control pesticide use in the agricultural sector. The countries with the highest usage of pesticide are Thailand, Philippines and Malaysia. Most Southeast Asian countries have emphasized safety practice in the management of pesticide usage, but there were less emphasis on the element of protection of workers within the framework in Indonesia, Myanmar, Thailand and Vietnam. Conclusion: The governing bodies in the countries of Southeast Asia have placed significant effort to develop framework related to pesticide management at the country level. The implementation of pesticide management based on the existing framework is evident in most of the countries but needs to be improved. It is suggested that emphasis be given to the implementation of diagnosis, health surveillance and reporting system as well as following or adopting standard guidelines for the protection of workers in terms of safety and health in the agricultural sector.