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.
This study aimed to investigate the concentrations of copper (Cu), zinc (Zn), nickel (Ni), lead (Pb) and iron (Fe) in different parts of guava (pulps, peels and seeds) and its topsoil collected from Kluang, Malaysia, and to assess their effects on human health. The level of metals was determined using acid digestion method and atomic absorption spectrometry. The result showed that the concentrations of Cu, Zn and Pb in all parts of guava were above the World Health Organization (WHO) permissible limits. However, the value of heavy metals in the topsoil were below the WHO limit. The concentration order of the metals in the guava's pulps was Fe > Cu > Zn > Pb > Ni. The contamination factor (Cf ) calculated from the topsoil were low for Cu, Zn and Ni and moderate for Pb. However, potential ecological risk (Er) of individual metal ranged from 0.25-7.58 for Cu, Zn, Pb and Ni was low. The potential non-carcinogenic health risk for consumers was assessed using estimated daily intake (EDI) and target hazard quotient (THQ). The contribution of heavy metals to the EDI for all consumers followed the order of Fe > Cu > Zn > Pb > Ni. The THQ values are all below 1 for all five metals tested, indicating no potential risk to the consumers. We suggest that the Kluang's guava is safe to consume. However, regular monitoring and human health risk assessment of heavy metals in the guava is recommended to be carried out.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.