Perfluorinated compounds such as perfluorooctane sulfonate (PFOS) and perfluorooctane acid (PFOA) have been recognized as emerging environmental pollutants because of their ubiquitous occurrence in the environment, biota and humans. The paper focuses on the distribution, bioaccumulation and toxic effects of PFOS and PFOA in the water. From the available literature, tap and surface water samples in several countries were found to be contaminated with PFOS and PFOA. These compounds were detected globally in the tissues of fish, bird and marine mammals. Their concentrations from relatively more industrialized areas were greater than those from the less populated and remote locations. Blood samples of occupationally exposed people and the general population in various countries were found to contain PFOS and PFOA which suggested a possibility of atmospheric transport of these compounds. There is still a death of information about the environmental pathways of PFOS and PFOA. The presence of these compounds in the tap water, surface water and animal and human tissues indicates their global contamination and bioaccumulative phenomena in the ecosystems.
The Analytic Hierarchy Process (AHP) has been used widely to solve multi-criteria selection problem. It is a technique that allows the decision makers to set their priorities and help make the best selection when both tangible and intangible aspects need to be considered. This study uses the AHP to select the best composting technology for the UKM composting centre where the accumulation of organic wastes are generated daily from the cafeteria and landscape activities within the UKM campus. Experts who are familiar and who have some years of experience on solid waste management at UKM were interviewed to do the pair wise comparisons which are structured with four criteria namely environmental, economy, social and technical aspects. These criteria then expanded into a few more sub-criteria. The alternatives for the composting technology are windrow composting and in-vessel composting. The analysis is done using the Super Decisions software. The result shows that technical factor is the most important factor with (0.5000), followed by environmental (0.2517), economy (0.1941) and social (0.0542) factors. The end result shows that windrow composting is the best composting technology according to these four factors with the priority of 0.6236 while composting in—vessel has the priority of 0.3765.
Composting is one of the alternatives that can be used in waste management to control the increment of waste generation including that is in Universiti Kebangsaan Malaysia (UKM). However, a conventional composting is rarely applied due to the longer time consumed to reach maturity phase. This research is focus on the use of effective microbes (EM) that will accelerate the composting process hence composting can be an alternative to treat the problem of organic waste in UKM.This research which took 7 weeks of completion is intend on finding the best EM that can be used to accelerate the composting process. Two types of organic waste are being used in this composting process which is yard waste and food waste. Two EM are applied in this research which is Takakura EM and Fruit Waste EM. The parameters which include temperature, moisture content, pH value, C:N ratio, NPK (Nitrogen, Phosphorus, Potassium) value and heavy metals concentrationhave been examined. The composting methods applied in this research are composter barrel and rotary drum. Based on the result of observations and experiments after 7 weeks, all pH values for the composts are approximately at neutral value (7.0-8.0) showing that the compost has approached mature phase. For C:N ratio, all of the compost has reached a value of less than 20:1 which is suitable to be used for agriculture. NPK content for potassium is from 0.073 to 0.133 and for phosphorus is from 0.049 to 0.512. For heavy metals, all compost has low levels of heavy metals where it is safe to use for agricultural. Thus, it is concluded that the quality of compost for this research is good and EM Takakura is said to be the suitable solution in decreasing the time taken for composting.
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.