The widespread occurrence of microplastic has invaded the environment to an extent that it appears to be present throughout the globe. This review investigated the global abundance and distribution of microplastics in marine and freshwater ecosystems. Furthermore, the issues and challenges have been addressed for better findings in microplastics studies. Findings revealed that the accumulation of microplastics varies geographically, with locations, hydrodynamic conditions, environmental pressure, and time. From this review, it is crucial that proper regulations are proposed and implemented in order to reduce the occurrence of microplastics in the aquatic environment. Without appropriate law and regulations, microplastic pollution will eventually threaten human livelihood.

Solid waste generation and its implications for people and the environment are global issues. The complexity of the waste composition and the ever-increasing percapita waste generation is a challenge for waste managers, particularly in developing countries. Thus, the need to have a clear policy on waste management and legislation to realize that policy is imperative. Malaysia is developing rapidly and problems such as the waste generation associated with development and industrialization are evident. The Solid Waste and Public Cleansing Management Bill, which was approved in August 2007 after a 10-year delay, is envisaged to have serious consequences in waste management practices and implementation in Malaysia. This article explores the main features of this all-encompassing bill and its impacts on the waste management scenario in Malaysia. In addition, a comparative evaluation is also discussed to explore the policies/legislation of selected countries vis-à-vis the Malaysian bill.

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Carbide sludge (10.4-11.5 tonnes day(-1)) is generated from the reaction of calcium carbide (900 kg) and water (6,000 L) in the production of acetylene (2,400 m3), in three selected acetylene manufacturing plants. The sludge (of pH 12.2 and containing Cu, Pb, Fe, Mn, Ni and Zn ions whose concentrations exceed the Department of Environment limits for industrial wastewater) was treated by vacuum filtration as a substitute for the ponding system, which is environmentally less acceptable. A similar system by flocculation was also developed. The filtration system represents an improvement over the ponding method, as shown by a pH of 7 for the clear filtrate; the solid cake, which contains 98% of the metals, can be conveniently disposed at an integrated scheduled waste treatment centre.

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