Chemical speciation of heavy metals in bioaugmented and non- bioaugmented soils from Taman Beringin landfill

Heavy metal pollution has led to serious consequences since the dawn of industrialization. The aim of this study is to compare the speciation of heavy metals in bioaugmented and non-bioaugmented soils from Taman Beringin landfill, Malaysia. This is to allow the proper understanding of the specific forms of heavy metals and their mobility in the environment. Sequential extraction process based on Tessier et al. (1979), Tsang et al (2007) and standard ISO 11466 (1995) was performed for the determination of eight heavy metals (Cr, Mn, Co, Ni, Cu, Zn, Cd and Pb) in soils samples. The results revealed that the percentage reduction of the mobile and non mobile forms (F1, F2, F3, F4 and F5) of heavy metals varied for all metals in non- bioaugmented and bioaugmented soils. Additionally, the distribution of the specific form of the metals ( for Mn, Co, Ni, Cu and Pb) changed after bioaugmentation at Day 100

Landfills in Malaysia: Past, present and future

In Malaysia, the absence of an integrated waste management system resulted with more than 10.40 million tonnes of municipal solid waste (MSW) being disposed off into landfills annually. This highlights the importance of landfills in MSW management in Malaysia. However, sustainable landfilling technology is yet to be achieved. This paper deliberates the scenarios of landfilling in Malaysia. Past and present status is thoroughly discussed while future prospects will be scrutinized. During the 1970s, the disposal sites were small and mere open-dumping grounds to cater small communities. With the population expansion in the 80s a national program was developed to manage municipal and industrial wastes more systematically. Early 1990s saw the privatization of waste management in Malaysia, and the establishment of the first sanitary and secure landfills. A more systematic waste management was gradually in place by end of 1990s. However, the absence of an integrated waste management resulted with landfills being pre-maturely closed. The flow of events had eventually led to the passing of the Solid Waste and Public Cleansing Management Act 2007. Even though the bill is yet to be implemented, the government has taken big steps to improve waste management system further. Future waste management in Malaysia seems somewhat brighter with a clear waste management policy in place. Therefore it is hoped that waste management and landfilling can be more sustainable in the near future

Microplastics Abundance and Uptake by Meretrix lyrata (Hard Clam) in Mangrove Forest

The aim of this study was to determine the abundance and distribution of microplastics in a mangrove ecosystem, while investigating its uptake by Meretrix lyrata. Microplastics were extracted from 10 L of mangrove sediment using a floatation method. Soft tissues of M. lyrata were digested and the microplastics were filtered and observed under a light microscope. Microplastics ranging from 21 µm to 100 µm were the most abundant in the mangrove layers at 936 ± 34 particles/kg (dry sediment) to 1,227 ± 55 particles/kg (dry sediment) (27.19% to 31.16% of the total quantity of recovered microplastics). The most abundant microplastics, with size from 5 µm to 1000 µm, were found in the deepest layer. M. lyrata accumulation of microplastics averaged at 0.35 ± 0.08 particles/g tissue and 0.23 ± 0.07 particles/g tissue (wet weight) before and after three-day depuration, respectively. Microplastics with size from 5 to 20 µm were the most commonly uptaken by the clams, averaging at 58% to 72% for pre-depuration and post-depuration, respectively. This study revealed that the most predominant size of microplastics in the sediment was 5 µm to 20 µm, which concurs with the results of the microplastics most commonly accumulated by M. lyrata. It is believed that microplastics accumulation in mangrove areas increases over time. On the other hand, the uptake rate of microplastics by Meretrix lyrata decreases over time, flushing microplastics from its system more frequently

Biological Treatments for Petroleum Hydrocarbon Pollutions: The Eco-Friendly Technologies

Anthropogenic activities introduce petroleum hydrocarbons into the environments, and the remediation of the polluted environments using conventional physicochemical, thermal, and electromagnetic technologies is a challenging task, laborious work, and expensive. The ecotoxicological effects and human health hazards posed by petroleum hydrocarbon pollutions gave rise to the call for “green technologies” to remove petroleum hydrocarbon contaminants from polluted environments. It is imperative to transition from the conventional physicochemical treatments methods that are expensive to more eco-friendly biological treatment technologies that reduce energy consumption, chemicals usage, cost of implementation and enables more sustainable risk-based approaches towards environmental reclamation. The chapter summarises and gives an overview of the various biological treatment technologies adapted to the remediation of hazardous petroleum hydrocarbon polluted sites. Biological treatment technologies include; bioremediation, biostimulation, bioaugmentation, bioattenuation, bioventing, biosparging, bioslurry, biopiling, biotransformation, landfarming, composting, windrow, vermiremediation, phytoremediation, mycoremediation, phycoremediation, electrobioremediation, nanoremediation, and trichoremediation. They are green technology approaches widely adopted, scientifically defensible, sustainable, non-invasive, ecofriendly, and cost-efficient in the remediation of petroleum hydrocarbons polluted environments compared to the physicochemical, thermal, and electromagnetic treatments technologies, which are rather destructive and expensive. The chapter provides detailed illustrations representing the various biological treatment technologies for a comprehensive understanding and successful implementation with their subsequent benefits and constraints

Status of Microplastic Pollution in Aquatic Ecosystem with a Case Study on Cherating River, Malaysia

Microplastics are emerging contaminants owing to their potential to adsorb and release pollutants from the environment, transferring these pollutants to the food web. Most marine microplastics come from the terrestrial environment, mainly from inland freshwaters that are direct receivers of runoff from urban, industrial, and agricultural areas. The present study investigated the occurrence of microplastics in surface water samples taken from the Cherating river and the Cherating mangrove, Pahang along with a review of recent studies on microplastics abundance in aquatic ecosystems. Three sampling sites were established (two sites along the river and one site in a mangrove in the downstream of the river). In the up- and midstream regions, the river passes by residential, fishery and tourism areas, while the mangrove is located close to Cherating Beach. The highest microplastics abundance was discovered in the midstream region, with an average abundance 0.0070 ± 0.0033 particles/m3, followed by the mangrove (0.0051 ± 0.0053 particles/m3). Fragments with a size of 0.5 to 1.0 mm and white-colored microplastics were prevalent. The findings are similar to those from other microplastic studies (e.g. in Aveiro and Lisbon, Portugal; New England, USA; Kingston Harbour, Jamaica), but lower than microplastics studies in Asia (e.g. Yangtze river estuary and Hangjiang river, China). Overall, the findings provide background information on microplastics pollution in aquatic ecosystems

Public perception on Solid Waste and Public Cleansing Management Bill 2007 towards sustainable waste management in Malaysia

Lack of appropriate policy is the main constraint to sustainable waste management in Malaysia. As a result, the Solid Waste and Public Cleansing Management Bill (SWPCM) was approved in 2007. Its aims are to provide an act and regulate the manag ement of solid waste and public cleansing in order to maintain proper sanitation in the country. The Bill provides for the administrative bodies authorized in MSW management and the tribunal for solid waste management services. The objective of this paper is to investigate the perception of the public in regards to the current waste management system in the country and future waste management, particularly in relation to SWPCM Bill 2007. To accomplish this, questionnaires consisting of 45 questions were randomly distributed to 694 respondents to obtain 96% confidence level. Data collected were analyzed using SPSS. Results indicated that 86% of the public is satisfied with the current waste management system. The high satisfactory level probably is related to the fact that only reliable waste management contractors are appointed and renewed after an interim period. Contracts of waste managers with high number of complaints will not be renewed and they are directed to stop their collection services. Since the passing of the Bill, government had declared that unsatisfactory contractors will be terminated from their contract once the SWPCM Bill 2007 is enforced. However, 13% is dissatisfied with the collection frequency. The public (67-78%) has relatively high knowledge on the waste management issues such as final disposal option of the municipal solid waste and others. However, the majority of the public (69%) are not aware of the existence of SWPCM Bill 2007 and its passing by the parliament in August 2007. This is mainly due to the absence of notification to the general public from the ministry level. Responses from public regarding the deposit refund system was mainly negative where majority (87%) disagreed to pay deposit for returnable packaging materials as allocated in Part X of the Bill. This is due to the fact that the system is currently absent in the country and its introduction will affect the consumers’ economy as they will lose the deposits if they did not return the materials to the manufacturer. The majority (64%) of the respondents agreed with the regulation of segregation at source. This probably is due to the high awareness on waste disposal issues. Various campaigns were aired in mass-media indicating the deteriorating quality of the environment due to the indiscriminate disposal of MSW into landfill. Nevertheless, 97% are confident that the Bill will improve the current waste management system and able to promote a more sustainable solid waste management system for the country

Municipal solid waste management : a comprehensive study in Selangor / Fauziah Shahul Hamid

The disposal of 95% of the 1.4 million tonnes of MSW from Selangor, the fastest developing state in Malaysia, is rapidly exhausting landfill space and is also jeopardizing public health. Therefore, proper planning of waste management based on accurate information is essential. The objectives of this research are to collate data from landfills and to investigate the level of public awareness on waste management issues, to analyze the current pollution impacts of landfills and to propose viable options to improve the waste management system in the state. Nine non-sanitary landfills in Selangor were investigated for waste composition and quantification, detailed waste and leachate analysis and treatment, and methane oxidation studies, from 2002 to 2007. Public surveys (2003-2007) were conducted to determine the impact of socio-economic factors on waste management, while modeling of suitable waste management priorities was achieved using SWPlan software.The largest component of waste generated was organic waste (55%), followed by plastic(17%) and paper (13%), depicting typical developing countries’ waste generation profile.Organic waste was best treated via vermi-composting where 500g of 50% food waste and 50% vermi-compost can be fully degraded by 80g of Eisenia feotida within 21 days. This was found to be the most appropriate set-up for household scale vermi-composting.Indiscriminate disposal of MSW resulted with leachate and landfill gas emissions from the landfills averaging at 28,200L and 188,000m3, respectively. BOD5 of the leachate samples ranged from 62 – 322 mg/L, which is generally low due to dilution of the leachate with the surface run-off. COD averaged at 4,300 mg/L due to the presence of organic waste in the waste cells. Both COD and BOD5 exceeded the Standard B (EQA 1974) limit of 100mg/L and 50 mg/L, respectively. On the contrary, the metal elements in the leachate were mainly below the limit stipulated in Standard B (EQA 1974) with the exception of Cr. Leachate treatment studies demonstrated that the best combination was chemical treatment with ferric chloride at 0.8g/L at pH4, followed by the application of microbial cocktails. The removal efficiency was up to 70% for physico-chemical treatment while biological treatment removed another 35-73%, to enable all parameters to be below the Standard B (EQA 1974). On the other hand, the emission of CH4 can be reduced via CH4 oxidation. Wheaton bottle experiments identified that soil from active waste cell was the most suitable cover media to enhance rapid CH4 oxidation. The optimal temperature ranged from 30-40oC, while optimal moisture content was 5-10%. Approximately 76% of the public are aware of the MSW issues in Selangor but less than 25% are willing to participate in 3Rs. This indicated that environmental awareness alone is insufficient to improve the environmental quality of a country. However, the majority of the public in Selangor indicated their willingness to participate if recycling is made mandatory. Therefore, the implementation of Solid Waste and Public Cleansing Management (SWPCM) Act 2007, is expected to make a major impact on the current waste management system in the state, particularly in raising the rate of recycling in Selangor. Computation using SWPlan indicated that recycling will generate an annual revenue of RM7 million (USD2 million) while composting could generate RM46 million(USD13.1 million) per year. Also, landfill management costs will be reduced by 75%.Integrated waste management options (recycling, composting, leachate and landfill gas treatment) are economically advantageous and offer a more sustainable solution for waste management in Selangor

Pollution impact of MSW landfill leachate

Improper disposal of Municipal Solid Waste (here after referred to MSW) into landfills not only creates a conducive environment for pests like flies, rats and others but also pollutes the ecosystem with the release of leachate. This study was conducted to analyze leachate characteristics and compare pollution intensity among three landfills of different level of urbanization namely urban landfill, sub-urban landfill and rural landfill. Leachate from Kundang landfill representing the urban type showed the highest COD value (6230 mg/l) among the three landfills. Both the rural type (Panchang Bedena landfill) and sub-urban type (Sungai Sedu landfill) have COD at 5060 mg/l and 170 mg/l, respectively. The pH ranged between 6.7 - 8 in all three landfills, whereas the TSS was 1.6 mg/l, 0.09 mg/l and 0.06 mg/l, at the rural, sub-urban and rural types, accordingly. In the urban landfill, the concentration of Cr, Cu, Pb, Zn, and Mg were 0.193 ppm, 0.003 ppm, 0.027 ppm, 0.06 ppm, and 4.25 ppm, respectively while Cr was not detected. The quantum of pollution from the released leachate to adjacent rivers was low with BOD value of 1240 g/day, 670 g/day and 3240 g/day from the urban, sub-urban and rural landfill, respectively. The concentration of metals, particularly Mg, was high which requires a proper wastewater treatment plant to be installed in order to prevent euthrophication in water bodies. Physical and chemical treatment would be the best option to reduce the pollution impact to the environment due to the low BOD to COD ratio (0.004 to 0.13) and the high metal content in the leachate