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The establishment of the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) is one of the global initiatives to promote effective chemical hazard communication worldwide. ...

This investigation quantified spatial variability of heavy metals and followed methods of the U.S. Environmental Protection Agency (EPA) to estimate the hazard indices as well as cancer risks associated with consuming fish caught in the waters of the Langat river basin area, Malaysia. The calculation of metal pollution index (MPI) was carried out to classify the study area according to the level of contamination and the order of stations from highest to lowest MPI values was Langat river > Cempaka lake > Engineering pond > Pond B > Pond A > Jugra > Bandar. The level of exposure due to the consumption of each chemical in Tilapia fish tissue was estimated in an average daily dose equation. The calculated HI ranging from 0.24 to 1.88 indicated 71% stations were in the risk level. Potential carcinogenic risks associated with the ingestion of heavy metals in Tilapia fish were evaluated probabilistically by performing 10,000 trials for Monte Carlo simulation. Cancer risk calculations exceeding the U.S. EPA’s acceptable risk level of 1 in 1,000,000 (or 10-6) included Ni (7.3×10-4) and Cd (2.1×10-6). However, the average carcinogenic risk (2.4×10-4) exceeded the accepted risk level to a great extent. The recommended daily ingestion rate of Tilapia for Malaysian people inhabiting Langat river basin area was calculated considering 95th percentile TR value of 10-6 as an acceptable risk where it is revealed that consumption of Tilapia should be reduced about 67% from the current level to have an acceptable risk of cancer.

Background The Globally Harmonized System of Classification and Labeling of Chemicals (GHS) was developed to enhance chemical classification and hazard communication systems worldwide. However, some of the elements such as building blocks and data sources have the potential to cause “disharmony” to the GHS, particularly in its classification results. It is known that some countries have developed their own lists of classified chemicals in accordance with the GHS to “standardize” the classification results within their respective countries. However, the lists of classified chemicals may not be consistent among these countries. Method In this study, the lists of classified chemicals developed by the European Union, Japan, Malaysia, and New Zealand were selected for comparison of classification results for carcinogenicity, germ cell mutagenicity, and reproductive toxicity. Results The findings show that only 54%, 66%, and 37% of the classification results for each Carcinogen, Mutagen and Reproductive toxicants hazard classes, respectively are the same among the selected countries. This indicates a “moderate” level of consistency among the classified chemicals lists. Conclusion By using classification results for the carcinogenicity, germ cell mutagenicity, and reproductive toxicity hazard classes, this study demonstrates the “disharmony” in the classification results among the selected countries. We believe that the findings of this study deserve the attention of the relevant international bodies.

Awareness of both chemical safety and chemical security is important in order to avoid or reduce any adverse effects of chemical use; hence, both these topics should be incorporated into the educat...

An optical biosensor employing immobilized haloalkane dehalogenase (HLD), the halide degrading enzyme for the detection of halogenated organic in environmental water and drinking water samples was developed. The enzymatic biosensor was fabricated by incorporating H+ ion selective chromoionophore ETH5294 and HLD enzyme in a stacked chitosan films system on a glass slide. Hydrolytic dehalogenation of dichloroethane (DCA) by the carbon-halide degrading HLD enzyme resulting in the release of a halogen, a proton and a primary alcohol. The halocarbon concentration was optically transduced by the pH transducer layer as a result of protonation reaction of the chromoionophore pH indicator dye embedded in the underneath layer. The resulting colour change of the protonated chromoionophore was measured by fiber optic reflectance spectrophotometry method. Under optimized conditions the detection limit of the proposed reflectance-based enzymatic biosensor membrane was estimated to be 1 mg L−1 with a wide dynamic linear concentration range of 5–60 mg L−1 DCA (R2 = 0.9792) and satisfactory reproducibility within the relative standard deviation (RSD) range of 3.4–4.3%. Validation test demonstrated that the optical halocarbon biosensor could be a promising tool for rapid (6 min) in situ and direct evaluation of organohalide in river water, tap water and bottled water samples without any sample pre-treatment or extraction steps.

A reflectometric biosensor for enzymatic determination of halogenated organic pollutant in environmental water sample was developed. Polyacrylate microspheres modified with succinimide functional groups were employed as the substrate matrix for covalent immobilization of haloalkane dehalogenase (DhlA) enzyme, and ETH5294 Nile Blue chromoionophore (NBC) pH dye was physically immobilized on the acrylic micromatrix to function as an optical proton sensor. The hydrolytic dehalogenation of halocarbon catalyzed by the immobilized DhlA resulting in the release of a halogen and a proton, which protonated the immobilized NBC proton indicator, and a colour change of the biosensor from violet to blue was measured with a reflectance spectrophotometer for indirect quantification of the halogenated hydrocarbon concentration. The enzymatic halocarbon reflectance biosensor exhibited a dynamic linear response range of 1–30 mg L−1 1,2-dichloroethane (DCA) (R2 = 0.9762) with a detection limit of 0.3 mg L−1. The proposed enzymatic biosensor gave rapid response, within 2 min, towards the detection of 50 mg L−1 DCA at 662 nm, and demonstrated stable response up to 6 days of storage period at 4 °C and pH 8.0. Validation between the developed biosensor with standard gas chromatography–electron capture detector (GC-ECD) showed that both methods have a comparable accuracy in detecting halocarbon species.

Exposure to aluminium (Al) is inevitable in the daily life because of its abundance in the environmental media through natural processes. Meanwhile, several studies have reported a positive association between Alzheimer’s disease and a higher level of Al ingestion through drinking water. The present study is the first of its kind in Malaysia which predicts the human health risk of Al ingestion via drinking water at the Langat River Basin, Malaysia. Water samples were collected during 2015–2016 from the four stages of drinking water supply chain at the basin to determine the concentrations of Al by the Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The determined mean concentration of Al in river 2.50E−01 ± 1.89E−01 mg/L crossed the Malaysian drinking water quality standard of 0.2 mg/L. The higher concentration of Al in the Langat River might be due to natural weathering of Al-bearing minerals. The mean Al concentrations in the treated water by the treatment plants, household’s tap and after filtration water, respectively, were found to be within the Malaysian drinking water quality standard. This study suggests that there is no potential human health risk of Al ingestion through drinking water (HQ = 3.81E−03 ± 1.82E−03) at 95% confidence level in the basin because the hazard quotient (HQ) value is less than 1. However, the authorities need to be careful of excessive ingestion of Al via drinking water because the water treatment plants in the basin follow the conventional method to treat raw water. The turbidity in the tropical Langat River changes very frequently; thus, the doses of Al2(SO4)3 for water disinfection are very crucial. Therefore, reverse osmosis technology can be introduced in the treatment plants because the United States Environmental Protection Agency has recommended that it can remove all types of metal > 90% from treated water.

Abundant of preparatory works have recognized that fluorescent sensors based on 8-aminoquinoline are popular tools to detect Zn2+ ions in environmental and biological applications. Along with these studies, researchers started to introduce a variety of carboxamido group into an 8-aminoquinoline molecule in forming 8-amidoquinoline derivatives. Therefore, this systematic review aims to introduce a general overview of the fluorophore 8-aminoquinoline as Zn2+ receptors and to provide comparisons of collected studies that related to 8-amidoquinoline derivatives as fluorophore probe of the sensor. According to PRISMA systematic searches strategy, 13 articles were analyzed for trends, research designs, results and discussion, subject samples, and remarks or conclusions. We found cross-sectional studies with four aspects in zinc sensing that have been targeted; binding studies via titration, detection's limit, interferences studies, and validation of the study. Hence, this paper also included assessments of those criteria and the trends of development of 8-amidoquinoline derivatives based-zinc fluorescent chemosensor. It also showed that most of the researches conducted in China. In conclusion, this study identified various research designs of fluorescent chemosensors based on 8-amidoquinoline prolong with the effectiveness and potential as a recognition probe to assist the detection of zinc. Hence, elucidation of those derivatives essential to be explored because more studies are needed to improve the sensing criteria of the zinc sensor

Prolonged persistence of toxic cadmium (Cd), chromium (Cr) and lead (Pb) in the aquatic environment are due to its nonbiodegradable characteristic. A few studies have reported higher concentrations of these metals in the transboundary Langat River, Malaysia. This study determined the spatial and temporal distributions of Cd, Cr and Pb concentrations (2005&ndash, 2015) in the Langat River along with assessing the status of these metals in the drinking water supply chain at the basin. Water samples were collected once in 2015 from the drinking water supply chain, i.e., from the river, treated water at plants, taps and filtration water at households. Determined mean concentrations of Cd, Cr and Pb by inductively coupled plasma mass spectrometry in the Langat River were within the drinking water quality standard of Malaysia and the WHO, except for the Pb (9.99 &plusmn, 1.40 &micro, g/L) concentration, which was at the maximum limit, 10 &micro, g/L. The spatial and temporal distribution of these metals&rsquo, concentrations indicate dilution of it downstream, along with the increasing trend in rainfall and water flow, especially during the northeast monsoon. Significant correlation and regression analysis of the Cd, Cr and Pb concentrations also indicate that the sources of this metal pollution are mainly the natural weathering of minerals along with anthropogenic activities in the basin. The determined overall water quality of the Langat River is categorized Class IIA (i.e., clean), which requires conventional treatment before drinking, however, the maximum removal efficiency of these metals by the plants at the basin was about 90.17%. Therefore, the proactive leadership roles of the local authorities will be appropriate to reduce the pollution of this river as well as introducing a two-layer water filtration system at the Langat River Basin to accelerate the achievement of a sustainable drinking water supply.

A DNA micro-optode for dengue virus detection was developed based on the sandwich hybridization strategy of DNAs on succinimide-functionalized poly(n-butyl acrylate) (poly(nBA-NAS)) microspheres. Gold nanoparticles (AuNPs) with an average diameter of ~20 nm were synthesized using a centrifugation-based method and adsorbed on the submicrometer-sized polyelectrolyte-coated poly(styrene-co-acrylic acid) (PSA) latex particles via an electrostatic method. The AuNP&ndash, latex spheres were attached to the thiolated reporter probe (rDNA) by Au&ndash, thiol binding to functionalize as an optical gold&ndash, latex&ndash, rDNA label. The one-step sandwich hybridization recognition involved a pair of a DNA probe, i.e., capture probe (pDNA), and AuNP&ndash, PSA reporter label that flanked the target DNA (complementary DNA (cDNA)). The concentration of dengue virus cDNA was optically transduced by immobilized AuNP&ndash, PSA&ndash, rDNA conjugates as the DNA micro-optode exhibited a violet hue upon the DNA sandwich hybridization reaction, which could be monitored by a fiber-optic reflectance spectrophotometer at 637 nm. The optical genosensor showed a linear reflectance response over a wide cDNA concentration range from 1.0 &times, 10&minus, 21 M to 1.0 &times, 12 M cDNA (R2 = 0.9807) with a limit of detection (LOD) of 1 &times, 29 M. The DNA biosensor was reusable for three consecutive applications after regeneration with mild sodium hydroxide. The sandwich-type optical biosensor was well validated with a molecular reverse transcription polymerase chain reaction (RT-PCR) technique for screening of dengue virus in clinical samples, e.g., serum, urine, and saliva from dengue virus-infected patients under informed consent.

Biosensor optik berasaskan hemoglobin (Hb) terpegun pada mikrosfera poli(n-butil akrilat-co-N-akriloksisuksinimida) [poli(nBA-NAS)] telah dibangunkan bagi mengesan kepekatan ion nitrit (NO2-). Kompleks HEM ferum dalam Hb memangkinkan tindak balas penurunan ion NO2- kepada nitrik oksida (NO) lalu bergabung dengan deoksihemoglobin (HbFe2+) membentuk kompleks ferum-nitrosil-hemoglobin (HbFe2+-NO) yang berwarna hijau kekuningan. Spektrofotometer pantulan gentian optik digunakan untuk memantau kepekatan ion NO2- secara kuantitatif berdasarkan perubahan warna Hb terpegun pada mikrosfera poliakrilat daripada perang kemerahan ke hijau kekuningan pada panjang gelombang pantulan maksimum 668 nm. Pencirian terhadap biosensor nitrit reflektometrik melibatkan ujian kesan pH, kesan kepekatan Hb, julat rangsangan linear, kebolehasilan, jangka hayat dan kesan gangguan ion telah dijalankan. Biosensor ion NO2- optik terbangun memaparkan julat linear dinamik daripada 5 hingga 50 mg mL-1 (R2=0.9894) pada pH7.0 dengan had pengesanan (LOD) sebanyak 3.3 mg mL-1 dan nilai sisihan piawai relatif (RSD) kebolehasilan biosensor sebanyak 5.8%. Jangka hayat biosensor optik nitrit tersebut adalah selama 36 hari dan majoriti ion asing yang sering wujud bersama ion NO2- dalam sampel air semula jadi tidak menunjukkan kesan gangguan yang bererti terhadap penentuan ion NO2- menggunakan biosensor optik terbangun kecuali ion Hg2+, Ag+, Br- dan S2-.

Benzene, toluene, ethylbenzene and xylenes (BTEX) are well known hazardous volatile organic compounds (VOCs) due to their human health risks and photochemical effects. The main objective of this study was to estimate BTEX levels and evaluate interspecies ratios and ozone formation potentials (OFP) in the ambient air of urban Kuala Lumpur (KL) based on a passive sampling method with a Tenax® GR adsorbent tube. Analysis of BTEX was performed using a thermal desorption (TD)-gas chromatography mass spectrometer (GCMS). OFP was calculated based on the Maximum Incremental Reactivity (MIR). Results from this study showed that the average total BTEX during the sampling period was 66.06 ± 2.39 μg/m3. Toluene (27.70 ± 0.97 μg/m3) was the highest, followed by m,p-xylene (13.87 ± 0.36 μg/m3), o-xylene (11.49 ± 0.39 μg/m3), ethylbenzene (8.46 ± 0.34 μg/m3) and benzene (3.86 ± 0.31 μg/m3). The ratio of toluene to benzene (T:B) is > 7, suggesting that VOCs in the Kuala Lumpur urban environment are influenced by vehicle emissions and other anthropogenic sources. The average of ozone formation potential (OFP) value from BTEX was 278.42 ± 74.64 μg/m3 with toluene and xylenes being the major contributors to OFP. This study also indicated that the average of benzene concentration in KL was slightly lower than the European Union (EU)-recommended health limit value for benzene of 5 μg/m3 annual exposure.

Heavy metals are widely used in various industries and became a great concern all over the world due to environmental contamination. This study provides an assessment of seasonal variability and risks to human health associated with the exposure to heavy metals concentrated in Langat river water of Malaysia. The Department of Environment (DOE) Malaysia kindly provided the heavy metal concentration data in water for this study. Several multivariate estimation such as an independent t test, box-and-whisker plot and Principal component analysis were carried out to evaluate the seasonal variation of metals concentration in water. The average value of ten analyzed metals was 250.81 µg/l and followed in order of abundance by August > Jun > February > October > April > December > March > May > September > January > July > November. The calculated HPI was 123.42, which is far above the critical index value of 100, indicating pollution with respect to heavy metals. Estimates of health risks associated with river water were summarized according to non-carcinogenic and carcinogenic health effects. No potential threat was detected for noncarcinogenic risk as the HI values calculated were

Science education emphasises on obtaining knowledge, in which includes hands-on knowledge involving experiments conducted in laboratories. However, since experiments require interactions between students, substances, and equipment, laboratories that can pose great risks to users. In this regards, the Ministry of Education Malaysia has taken proactive approach to enhance laboratory safety via School Science Laboratory Management and Safety guidebook, textbooks, and science based practical workbooks that are used throughout secondary schools in Malaysia. It is challenging to ascertain students’ awareness on laboratory safety throughout Malaysia, hence this study selected 8 secondary schools located in Pahang as case study to determine students’ awareness on laboratory safety. A questionnaire was developed by focusing on five components, namely work procedure, safety equipment, handling experiments, chemical waste management, and emergency response plan, and then the questionnaire was completed by 558 science stream students from schools located at urban and rural areas. The results of this study indicate that the overall level of students’ awareness on laboratory safety is at medium-high level, and this has shown that the existing measures in secondary school to enhance awareness of laboratory safety is adequate. Nevertheless, there are still room for improvement to further enhance students’ awareness on laboratory safety in Malaysia. Keywords: Laboratory safety, awareness, secondary school, Malaysia Pendidikan sains memberi kepentingan kepada pemerolehan ilmu dan memberi penekanan khusus kepada kerja amali yang dijalankan di dalam makmal sains. Memandangkan kerja amali memerlukan interaksi antara pelajar dengan pelbagai bahan dan peralatan, ia menjadikan makmal sains berisiko kepada penggunanya. Sehubungan dengan itu, Kementerian Pendidikan Malaysia telah memperkukuhkan keselamatan makmal melalui garis panduan Pengurusan dan Keselamatan Makmal Sains, buku teks dan buku amali yang digunapakai di sekolah menengah. Ia adalah mencabar untuk menentukan tahap kesedaran keselamatan makmal di seluruh Malaysia, maka kajian ini telah memilih 8 sekolah menengah yang terletak di Pahang sebagai kajian kes. Soal selidik telah dibangunkan dengan memberi fokus kepada lima komponen utama keselamatan makmal sains, iaitu prosedur kerja, peralatan keselamatan, pengendalian eksperimen, pembuangan sisa bahan kimia dan pelan tindakan kecemasan, dan kemudian soal selidik ini telah dijawab oleh 558 pelajar sains dari sekolah bandar dan luar bandar. Hasil kajian menunjukkan bahawa tahap kesedaran keseluruhan untuk keselamatan makmal adalah pada tahap sederhanda-tinggi, dan ini telah menunjukkan kaedah sedia ada di sekolah menengah adalah memadai. Walaubagaimanapun, ia masih terdapat peluang untuk penambahbaikan serta memperkukuhkan tahap kesedaran pelajar terhadap keselamatan makmal di Malaysia. Kata kunci: Keselamatan makmal, kesedaran, sekolah menengah, Malaysia

Mass-spectrometry-based and X-ray fluorescence-based techniques have allowed the study of the distribution of Zn2+ ions at extracellular and intracellular levels over the past few years. However, there are some issues during purification steps, sample preparation, suitability for quantification, and the instruments’ availability. Therefore, work on fluorescent sensors based on 8-aminoquinoline as tools to detect Zn2+ ions in environmental and biological applications has been popular. Introducing various carboxamide groups into an 8-aminoquinoline molecule to create 8-amidoquinoline derivatives to improve water solubility and cell membrane permeability is also a recent trend. This review aims to present a general overview of the fluorophore 8-aminoquinoline and its derivatives as Zn2+ receptors for zinc sensor probes. Various fluorescent chemosensor designs based on 8-amidoquinoline and their effectiveness and potential as a recognition probe for zinc analysis were discussed. Based on this review, it can be concluded that derivatives of 8-amidoquinoline have vast potential as functional receptors for zinc ions primarily because of their fast reactivity, good selectivity, and bio-compatibility, especially for biological applications. To better understand the Zn2+ ion fluorophores’ function, diversity of the coordination complex and geometries need further studies. This review provides information in elucidating, designing, and exploring new 8-amidoquinoline derivatives for future studies for the improvement of chemosensors that are selective and sensitive to Zn2+.

An optical aptasensor-based sensing platform for rapid insulin detection was fabricated. Aminated porous silica microparticles (PSiMPs) were synthesized via a facile mini-emulsion method to provide large surface area for covalent immobilization of insulin-binding DNA aptamer (IGA3) by glutaraldehyde cross-linking protocol. A Nickel-salphen type complex with piperidine side chain [Ni(II)-SP] was synthesized with a simple one-pot reaction, and functionalized as an optical label due to strong π-π interaction between aromatic carbons of G-quadruplex DNA aptamer and planar aromatic groups of Ni(II)-SP to form the immobilized IGA3-Ni(II)-SP complex, i.e. the dye-labeled aptamer, thereby bringing yellow colouration to the immobilized G-quartet plane. Optical characterization of aptasensor towards insulin binding was carried out with a fiber optic reflectance spectrophotometer. The maximum reflectance intensity of the immobilized IGA3-Ni(II)-SP complex at 656 nm decreased upon binding with insulin as aptasensor changed to brownish orange colouration in the background. This allows optical detection of insulin as the colour change of aptasensor is dependent on the insulin concentration. The linear detection range of the aptasensor is obtained from 10 to 50 μIU mL−1 (R2 = 0.9757), which conformed to the normal fasting insulin levels in human with a limit of detection (LOD) at 3.71 μIU mL−1. The aptasensor showed fast response time of 40 min and long shelf life stability of >3 weeks. Insulin detection using healthy human serums with informed consent provided by participants suggests the DNA aptamer biosensor was in good agreement with ELISA standard method using BIOMATIK Human INS (Insulin) ELISA Kit.

Lack of treated water system in Sabah has increase human dependency to groundwater sources. The presence of contaminants such as nitrate in groundwater can pose severe health implications to human, such as methemoglobinemia and cancerous diseases. The objectives of this paper were to quantify the nitrate concentration in groundwater, to calculate potential human health risk exposure of nitrate in groundwater and to compare the potential human health risk exposure of nitrate between rural and agriculture areas. Six tube wells were selected at Inanam and Kota Belud district and involved one-hundred eighty respondents aged from 7 to 12 years old. The groundwater samples were analyzed using Cadmium Reduction method of HACH DR2800 Spectrophotometer and human health risk exposure were assessed using Chronic Daily Intake (CDI) and Hazard Index (HI) after set of information of respondents were obtained by questionnaires. Result obtained were showing mean ± S.D of nitrate levels in groundwater well and filtered water of agriculture (0.79 ± 0.33 mg/L; 0.33 ± 0.29 mg/L) and rural (0.50 ± 0.12mg/L; 0.53 ± 0.10 mg/L) areas were within the acceptable value limit set by National Drinking Water Quality Standard of Malaysia (10 mg/L). The statistical analysis of Kruskal-Wallis and one-way ANOVA test implied there were no significant differences of nitrate levels between two areas (p>0.05). Moreover, the mean ± S.D of CDI for agriculture and rural areas were 0.0064 ± 0.0056 mg/kg/day 0.0140 ± 0.0096 mg/kg/day respectively and HI were less than 1. The insignificant differences of potential human health risk were noted in terms of gender and age of respondents between two areas. This specified that the human health risk of respondents involved in this study was in acceptable range and not exposed to severe health risks.

The presence of toxic polonium-210 (Po-210) in the environment is due to the decay of primordial uranium-238. Meanwhile, several studies have reported elevated Po-210 radioactivity in the rivers around the world due to both natural and anthropogenic factors. However, the primary source of Po-210 in Langat River, Malaysia might be the natural weathering of granite rock along with mining, agriculture and industrial activities. Hence, this is the first study to determine the Po-210 activity in the drinking water supply chain in the Langat River Basin to simultaneously predict the human health risks of Po-210 ingestion. Therefore, water samples were collected in 2015&ndash, 2016 from the four stages of the water supply chain to analyze by Alpha Spectrometry. Determined Po-210 activity, along with the influence of environmental parameters such as time-series rainfall, flood incidents and water flow data (2005&ndash, 2015), was well within the maximum limit for drinking water quality standard proposed by the Ministry of Health Malaysia and World Health Organization. Moreover, the annual effective dose of Po-210 ingestion via drinking water supply chain indicates an acceptable carcinogenic risk for the populations in the Langat Basin at 95% confidence level, however, the estimated annual effective dose at the basin is higher than in many countries. Although several studies assume the carcinogenic risk of Po-210 ingestion to humans for a long time even at low activity, however, there is no significant causal study which links Po-210 ingestion via drinking water and cancer risk of the human. Since the conventional coagulation method is unable to remove Po-210 entirely from the treated water, introducing a two-layer water filtration system at the basin can be useful to achieve SDG target 6.1 of achieving safe drinking water supplies well before 2030, which might also be significant for other countries.

Water is not only a resource, it is a life source; therefore, the water should be healthy, secure, and sustainable for people. Watersheds are nature’s boundaries for surface water supplies, and thus, the quality of the drinking water at a consumer’s tap depends on the quality of watershed. The risk assessment which is a process used to define the probability and magnitude of adverse effects of an environment from stressors can be used to estimate the costs and benefits of changes in a watershed in terms of risk. This chapter describes the source of pollution and the framework for assessing risk in Malaysian watershed.

Due to inadequate planning, rapid development and urbanization have polluted watersheds. Hence, watersheds must be managed properly to ensure their sustainability, by taking into account the importance of landscape and ecology and different socio-economic conditions, culture and religion. Among others, one of the ways to enhance watershed management is via adequate institutional arrangement and legal framework. This chapter has selected Malaysia as a case study, and by focusing on the discharge of pollutants, this chapter demonstrates how both federal and state governments complement each other to strengthen the regulatory framework in preventing pollution in watersheds. While the federal government regulates the discharge from manufacturing processes, the state government regulates activities that are not covered by the federal government, such as aquaculture and farming.

Watersheds provide ecological services that benefit flora and fauna, and people are also benefited from the ecological services, particularly for living and development purposes. Hence, watersheds must be managed in holistic and integrated manners to ensure their sustainability. Nonetheless, rapid development has polluted watersheds, and some of the watershed pollutants are chemicals and hazardous substances. This chapter explains the concept of chemical risk and introduces a framework for chemical risk assessment and management that takes into account the importance of human and environmental health. The chapter also discusses chemicals that cause air pollution (such as ground-level ozone and asbestos) and water pollution (such as different types of heavy metals). In the conclusion, this chapter highlights that we cannot avoid dealing with chemicals in our daily life but we can reduce the risks associated with them.

Integrated Langat River Basin Management lacks appropriate leadership of appropriate agency due to the conflict among jurisdictions since Langat River drains through three different constituency. Meanwhile, pollution of the river and frequent shutdown incidents of water treatment plants in the basin are evident due to both point and non-point sources of pollutions. Moreover, the statistically significant trend of annual rainfall (2005-2016) and temperature (2005-2016) in the basin clearly indicates the impact of climate change because of uncertain rainfall and temperature patterns. Flood incidents (2004-2016) within the basin in comparison with the rainfall and temperature also indicate short duration heavy rainfall at local level to enhance the pollution of the river. Contrary, the review of literature and informal interviews with the public, private and civil sectors highlight the attitude problem of the stakeholders along lack of leadership of LUAS in managing the river and drinking water in the basin. Therefore, the ‘proactive’ leadership of Local Authority under the Local Government Act 1976 could be successful to coordinate with stakeholders through multi stakeholders’ platform and several stages of quality control and quality assurance to manage water resources. The study suggests a new Langat Basin Management Authority under the Local Authority leadership as well as a Two-Layer water filtration technology in basin management. Henceforth, implementing the recommendations will facilitate Malaysia to achieve SDGs 2030 and National Transformation 2050 within the stipulated timeframe.

For the determination of glufosinate ammonium residue in soil and water samples, different solid phase extraction (SPE) sorbent efficiency was studied. Four different SPE sorbents i.e.: CROMABOND PS-H+, CROMABOND PS-OH−, ISOLUTE ENV+, Water Sep-Pak and OASIS HLB were used. Sample clean-up performance was evaluated using high performance liquid chromatography (Agilent 1220 infinity LC) with fluorescence detector. Detection of FMO-derivatives was done at λ ex = 260 nm and λ em= 310 nm. OASIS HLB column was the most suitable for the clean-up in view of the overall feasibility of the analysis.

The European Union (EU) and the World Health Organization (WHO) have applied different approaches to facilitate the implementation of the UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS). The EU applied the mandatory approach by gazetting the EU Regulation 1272/2008 incorporating GHS elements on classification, labelling and packaging of substances and mixtures in 2008; whereas the WHO utilized a voluntary approach by incorporating GHS elements in the WHO guidelines entitled 'WHO Recommended Classification of Pesticides by Hazard' in 2009. We report on an analysis of both the mandatory and voluntary approaches practised by the EU and the WHO respectively, with close reference to the GHS 'purple book'. Our findings indicate that the mandatory approach practiced by the EU covers all the GHS elements referred to in the second revised edition of the GHS 'purple book'. Hence we can conclude that the EU has implemented the GHS particularly for industrial chemicals. On the other hand, the WHO guidelines published in 2009 should be revised to address concerns raised in this paper. In addition, both mandatory and voluntary approaches should be carefully examined because the classification results may be different.

Chemical classification and labelling systems may be roughly similar from one country to another but there are significant differences too. In order to harmonize various chemical classification systems and ultimately provide consistent chemical hazard communication tools worldwide, the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) was endorsed by the United Nations Economic and Social Council (ECOSOC). Several countries, including Japan, Taiwan, Korea and Malaysia, are now in the process of implementing GHS. It is essential to ascertain the comprehensibility of chemical hazard communication tools that are described in the GHS documents, namely the chemical labels and Safety Data Sheets (SDS). Comprehensibility Testing (CT) was carried out with a mixed group of industrial workers in Malaysia (n=150) and factors that influence the comprehensibility were analysed using one-way ANOVA. The ability of the respondents to retrieve information from the SDS was also tested in this study. The findings show that almost all the GHS pictograms meet the ISO comprehension criteria and it is concluded that the underlying core elements that enhance comprehension of GHS pictograms and which are also essential in developing competent persons in the use of SDS are training and education.

After the 1970s, Malaysia's economy diversified from agriculture into manufacturing. The manufacturing sector's contribution grew from a mere 13.4% of the total GDP in 1970, to 30.3% of the GDP in 2007. Realising that increasing industrialisation causes threats to the environment, Malaysia has always emphasised environmental protection. The 2008 Environmental Performance Index (EPI) study carried out by Yale University and Columbia University ranked Malaysia 26th out of 149 countries that participated in the study. However, there are still a number of challenges that need immediate attention, particularly issues pertaining to chemical management. Several initiatives pertaining to chemical management are currently carried out by various agencies across government, private sector and civil society but these initiatives take a sectoral approach. Several structures are suggested towards the establishment of a sound chemical management system (CMS) in Malaysia, namely the gazetting of a Chemical Act, the establishment of a designated Chemical Authority and the development of a Malaysian Chemical Database (MyCD). A set of economic policy instruments is also prescribed in this paper to aid the appropriate authorities in their efforts to materialize a sound chemical management system in Malaysia. Refereed/Peer-reviewed

Received May 7, 2009; Accepted Aug 25, 2009 Published online in J-STAGE Oct 16, 2009 Correspondence to: G.C. Ta, Institute for Environment and Development (LESTARI), Universiti Kebangsaan Malaysia (UKM), 43600 UKM BANGI, Selangor, Malaysia (e-mail: gohchoota@ukm.my) Model for the Implementation of the Globally Harmonized System of Classification and Labelling of Chemicals (GHS): Lessons Learned from Japan

A colorimetric biosensor using immobilised alkaline phosphatase (AP) to detect Hg/sup 2+/ was developed. Copolymer poly(2-hydroxyethyl methacrylate-co-butyl acrylate) (poly(HEMA-co-BA)) were use as matrix to entrap AP. It was discovered that incubation time was needed before the mixture of HEMA/BA and AP (in Tis-HCl) undergo UV-initiated photopolymerisation due to hydrophilic and hydrophobic characteristic of monomer HEMA and nBA, respectively. Sensors HB91-AP, HB82-AP and HB73-AP showed a similar optimum pH at pH 8.5. Quantitative determination of Hg/sup 2+/ using sensor, generate a linear response range from 1 - 5 mM Hg/sup 2+/(R/sup 2/ = 0.9247).