A study was undertaken to determine the effect of polyethylene and polystyrene used in the manufacture of plastic items on colour perception. Colour vision was assessed using the Ishihara plates, panel 015 test and the Farnsworth Munsell 100-Hue test. Two factories were chosen at random. One factory (referred here as factory A) used virgin resin in pellet form (polyethylene) in the manufacturing of plastic containers to store consumer edible oil. The other factory (referred as factory B) used polystyrene to make plastic bags. A total of 39 healthy employees from factory A (mean age 26.4 :t 8.2 years) and 40 healthy employees from factory B (mean age 26.8 :t 9.6 years) were recruited in this study. A control group of 27 normal healthy subjects (mean age 27.4 :t 4.3 years) who were employees of UKM with no occupational involvement with petroleum derivatives were also recruited in this study and they performed the same colour vision tests. All subjects passed the Ishihara plates test showing that none of the subjects (employees of factory A and B, and control subjects) had a congenital red-green defect. All control subjects passed all of the colour vision tests whilst some employees of factories A and B failed the 015 and FM100 Hue tests. For employees from factory A results from the 015 test showed that 7 (17.9%) had a tritan (blue-yellow) type of defect and 1 (2.6%) had a complex type of defect. The FM 100 Hue results of factory A employees showed that 51.3% (n=20) had a complex type of defect. Total error scores (TES) calculated from the FM 100 Hue test revealed that employees from factory A had a statistically significant higher mean TES of 65.13:!: 48.31 compared to that of control subjects with a mean TES of 31.26:!: 14.93. For employees in factory B, 10 employees (25.0%) had a tritan (blue-yellow) type of defect and 2 (5.0%) had a complex type of defect. Results of the FM 100 Hue test showed that 4 employees (1.0%) had a tritan type of defect whereas 22 (55.0%) had a complex type of defect. Mean total error scores (TES) calculated from the FM 100 Hue test revealed that employees from factory B had a statistically significant higher mean TES of 71.54 :t 54.63 compared with that of control subjects with a mean TES of 31.26 :t. 14.93
The above results show that employees of the plastic factories studies are associated with a higher risk of acquiring colour vision defects as compared to normal subjects who are not engaged in the plastic manufacturing industry. This may have an implication towards the future retinal health of employees in petrod1emical-based industries.
MeSH terms: Color Vision Defects; Color Perception; Color Perception Tests; Malaysia; Petroleum; Plant Extracts; Plastics; Polystyrenes; Resins, Plant; Polyethylene; Control Groups; Color Vision; Healthy Volunteers; Manufacturing Industry
Malaysia is blessed with oil and gas resources, which form raw materials for the petrochemical industry. The petrochemical industry creates added value to this resource and is an important contributor to the national economy. The petrochemical industry however also creates hazards of which fire or explosions and chemical release are of special concern. These hazards pose a risk not only to workers but also to the surrounding population and environment. To ensure industry is prepared to cope with emergencies, a comprehensive emergency response programme is necessary. This is inline with both the Malaysian Occupational Safety and Health (Control of Industrial Major Accident Hazards) Regulations 1996 and the Responsible Care initiative of the chemical industry. This paper describes elements to be considered in an emergency response programme for industry such as the concept of emergency management, organisation, duties and responsibilities, emergency system, training and mutual aid plans and agreements. We shall provide related examples based on a multinational petrochemical company practice.
Radiotherapy causes various complications including low immunity. Past research has shown that the low immunity is due to the low amount of lymphocytes and consumption of citrullus vulgaris will alleviate this problem. Based on this a study was conducted to identify how citrullus vulgaris was able to produce radioprotection on the lymphocyte membrane. A total of 30 adult male Sprague-Dawley rats were used and divided into three equals groups of positive control, negative control and treatment. For seven days, positive control and negative control were force fed with normal saline of 40 ml/kg animal weight while the treatment group received 40 g/kg animal weight fresh juice of citrullus vulgaris daily. After a week positive control and treatment group were irradiated with 0.9 Gy gamma ray. Viable lymphocyte were determined using propidium iodine and acridine orange stain. Results clearly shows that positive control, negative and treatment group were significantly different at 34 3% , 80 2% and 71 2% respectively. SEM results shows that pores were present on the membrane of the positive control while the negative control had none. Similar results were also found on the treatment group. Based on the result it had shown that citrullus vulgaris had radioprotection properties and lymphocytes were destroyed by the formation of pores on their membrane. It is very likely that the radioprotection properties could be due to the presence of antioxidants particularly vitamin A, C and lycopene. In conclusion, citrullus vulgaris could be used as a safe radioprotection agent.
Various palm oil (RBD Palm Olein) based urethane acrylate prepolymers (UPs) having different structures and molecular weights were synthesised from palm oil based polyols, diisocyanate compounds and hydroxyl terminated acrylate monomers by following established synthesis procedures described elsewhere. The products (UPs) were compared with each other in terms of their molecular weights (MW), viscosities and UV curing performances of pressure sensitive adhesives (PSA) UP based formulations. The molecular structure of diisocyanate compounds and hydroxyl acrylate monomers tend to determine the molecular weights and hence viscosities of the final products of urethane acrylate prepolymers (UP), whereas, the MW of the UP has no direct effects on the coatings and adhesive properties of UV curable UP based PSA.
A laboratory scale test rig to treat simulated flue gas using electron beam technology was installed at the Alurtron EB-Irradiation Center, MINT. The experiment test rig was proposed as a result of feasibility studies conducted jointly by IAEA, MINT and TNB Research in 1997. The test rig system consists of several components, among others, diesel generator sets, pipe ducts, spray cooler, ammonia dosage system, irradiation vessel, bag filter and gas analyzers. The installation was completed and commissioned in October 2001. Results from the commissioning test runs and subsequent experimental work showed that the efficiency of flue gas treatment is high. It was proven that electron beam technology might be applied in the treatment of air pollutants. This paper describes the design and work function of the individual major components as well as the full system function. Results from the initial experimental works are also presented.
MeSH terms: Air Pollutants; Air Pollution; Ammonia; Electrons; Feasibility Studies; Laboratories; Research; Technology
The studies of ¹³⁷Cs content in the seawater surrounding Peninsular Malaysia had been carried out as part of the Malaysia Marine Radioactivity Database Project. The results of the measurement will serve as the baseline data and reference level to Malaysia. A numbers of sampling locations, including coastal and offshore at the East Coast (South China Sea) and West Coast (Straits of Malacca) of Peninsular Malaysia had been selected for the study. From each location at the coastal area, water samples were collected from the surface of the seawater. Meanwhile, for the offshore area, water samples have been collected at three different depths. Due to usual low concentration of ¹³⁷Cs in the marine environment, large volumes of seawater were collected and the co precipitation technique was employed to concentrate the ¹³⁷Cs. The activity of ¹³⁷Cs was determined by measuring the peak area under photo peak of the gamma spectrum at 661 keV, which is equivalent to the gamma intensity corrected to the HpGe detection efficiency and percentage of gamma ray abundance of the ¹³⁴Cs. At each study location, there were no significant differences for ¹³⁷Cs activities at 95% confidence interval. The activities of ¹³⁷Cs found to be quite uniformly distributed in the range of 2.33 to 5.00 Bq/m3and 1.76 to 4.76 Bq/m3for the South China Sea and the Straits of Malacca, respectively.
The main component of most building materials in Malaysia is rocks. These rocks have been found to naturally contain U-238, Th-232 and K-40. In order to estimate the radiological impact to the dweller, the level of radionuclides present in various building materials available in Malaysia were analyzed using gamma spectrometry. The radiation hazard indexes were calculated based on the above results. The results showed that the activity concentration of natural radionuclides U-238, Th-232, K-40 were between 19.0 Bq/kg – 42.2 Bq/kg, 16.5 Bq/kg –28.8 Bq/kg and 243.3 Bq/kg – 614.2 Bq/kg respectively. On the whole the radionuclides concentrations were still below the global average of 50 Bq/kg, 50 Bq/kg and 500 Bq/kg for U-238, Th-232 and K-40 respectively. The radiation hazard indexes of the building materials were also lower than the maximum value suggested.
MeSH terms: Construction Materials; Malaysia; Radioisotopes; Spectrometry, Gamma
The existence of Naturally Occurring Radioactive Materials (NORM) such as K-40 was studied all over the world for their characteristics and effects on human and environment. K-40 exist in the earth crust with the concentration about 1.8 mg/kg or 481 Bq/g.. In this study, the level of K-40 in soil samples were measured using gamma spectrometer equipped with hyper pure germanium detector. The samples were collected from an oil palm cultivated area of Jengka 15, in Maran District, Pahang. The results show the level of K-40 activities at various locations. The activities of K-40 are in the range 52.9-150.5 Bq/kg and total potassium concentrations are 1.60-4.50%. There are no correlation between activities of K-40 with elevation i.e. R2= 0.0885.
One of the non-destructive methods used for the identification and verification of metals is by the energy-dispersive X-ray fluorescence (EDXRF) technique. EDXRF analysis provides several important advantages such as simultaneous determination of the elements present, enable to analyse a very wide concentration range, fast analysis with no tedious sample preparation. The paper shows how this technique is developed and applied in the identification and verification of different grades of stainless steels. Comparison of the results obtained from this analysis with certified reference standards show very small differences between them.
Environmental radiation protection program is important in the effort to limit radiation dose to the public to be as low as reasonably achievable. As water is an important factor of transfer of radionuclide to human, therefore it is important to measure natural radionuclide concentrations in rivers. 20 water samples were collected randomly from the main rivers in Kota Tinggi district. The water samples collected were analysed using ICP-MS technique to determine uranium, thorium and potassium concentration in river water. Radionuclide concentrations obtained were compared with the terrestrial gamma radiation dose rate measured in the area. Significance of the results obtained is discussed.
The adsorption equilibrium time and effects of pH and concentration of ¹⁴C-labeled chlorpyrifos
O,O-diethyl O-(3, 5, 6 trichloro-2-pyridyl)-phosphorothiote in soil were investigated. Two types of Malaysian soil under oil palm were used in this study; namely clay loam and clay soil obtained from the Sungai Sedu and Kuala Lumpur International Airport (KLIA) Estates, respectively. Equilibrium studies of chlorpyrifos between the agricultural soil and the pesticide solution were conducted. Adsorption equilibrium time was achieved within 6 and 24 hours for clay loam and clay soil, respectively. It was found that chlorpyrifos adsorbed by the soil samples was characterized by an initial rapid adsorption after which adsorption remained approximately constant. The percentage of ¹⁴C-labeled chlorpyrifos adsorption on soil was found to be higher in clay loam than in clay soils. Results of the study demonstrated that pH affected the adsorption of chlorpyrifos on both clay loam and clay soils. The adsorption of chlorpyrifos on both types of soil was higher at low pH with the adsorption reduced as the pH increased. Results also suggest that chlorpyrifos sorption by soil is concentration dependent.
Spatial and temporal variations in concentrations of several metals and isotopes in sediment cores from around Penang Island, an area with economically important biological resources off the northwest coast of peninsular Malaysia, are reported. Because of a typical, monazite rich mineralogy in surrounding drainage basins, sedimentary metal enrichment factors relative to global average materials, enrichment factors (EFs) of ˃1.0 do not always indicate significant anthropogenic metal inputs. Because of extensive metal solubilization in the hot, organic carbon rich area, EFs of < 1.0 may be observed for several metals despite significant anthropogenic contributions. Comparison of metal-Al relationships in Penang area surface sediments with those in nearby and presumed uncontaminated Strait of Malacca sediments more accurately correct for atypical regional solubilization and mineralogical effects than comparison to global average materials. Such comparisons show concentrations of Cd, Cu, Pb, Ni, Cr, As, Sb, Zn and V have changed by less than a factor of two by anthropogenic discharges. Sedimentary concentration profiles of Pb, Zn and Cu, ratioed to Sc to normalize for variations in grain size and mineralogy, have subsurface maxima suggestive of modest and recently reduced anthropogenic inputs. Mn, U, As and Sb have Sc-normalized concentration profiles clearly affected by diagenetic processes. Sc-normalized profiles of Cr, Th, Ce and Sm show only small changes with depth, confirming insignificant anthropogenic inputs and undetectable postdepositional diagenetic mobility.
Excess ²¹⁰Pb activities and fluxes in Penang area sediments are limited by supply of this radionuclide, in contrast to sediments of both the northwestern U.S.A. and Amazon continental shelves, where they are limited by particle scavenging reactions.²¹⁰Pb activities in sediments of
the shallow, dynamic Penang area often show erratic or unconvincing changes with depth that
cannot be reliably modeled by assuming steady state, constant deposition rate of particles of
uniform chemistry, mineralogy and initial unsupported ²¹⁰Pb, and that mixing is limited to a
recognizable surface layer and resemble a diffusive process.
Malaysia, with her tropical jungles, mangroves and seas, is blessed with riches in biodiversity, being one of the twelve megabiodiversity countries on earth. Genetics has contributed substantially to the success of our country's agricultural production especially of rubber and palm oil. Hence, it should play a pivotal role in helping Malaysia fulfill her responsibility to identify, characterize and sustainably utilize her numerous indigenous bioresources for the benefit of humanity.
Cancer of the cervix is caused by micro-organisms called Human Papilloma Virus (HPV). This virus is only transmitted to women from their partners/spouses through sexual intercourse. In Malaysia, cancer of the cervix is the second most common cancer among females after breast cancer. The incidence is 21.5 per 100,000 population, with incidence among the Chinese being highest at 33.6 per 100,000 and among Malays the lowest being 12.6 per 100,000. For the past twenty years or so the Annual Reports of Ministry of Health recorded an average of 2500 new cases per year. Cancer of the cervix is preventable. The precursor cancer cells can be easily detected provided the women do regular screening tests called Pap Smear. In nearly all cases this cancer arises from the transformation
zone of the cervix. This is the zone in the cervical mucosa in which the epithelium abruptly changes from hardy squamous epithelium of the ectocervix to the fragile columnar epithelium of the endocervix.
Cervical cancer is the first solid tumour to be shown directly induced by virus. HPV is found in virtually all cervical carcinomas and their precursors.
MeSH terms: Breast Neoplasms; Uterine Cervical Neoplasms; Coitus; Epithelium; Female; Humans; Malaysia; Mucous Membrane; Incidence; Spouses; Papillomaviridae; Papanicolaou Test
Our purpose is to report on the epidemiological variables and their association with the results of the exercise tolerance test (ETT) in the series of patients referred for standard diagnostic ETT at Seremban Hospital during the year 2001. ETT is widely performed, but, in Malaysia, an analysis of the associations between the epidemiological data and the results of the ETT has not been presented. All patients referred for ETT at Seremban Hospital who underwent exercise treadmill tests for the year 2001 were taken as the study population. Demographic details and patients with established heart disease (i.e. prior coronary bypass surgery, myocardial infarction, or congestive heart failure) were noted. Clinical and ETT variables were collected retrospectively from the hospital records. Testing and data management were performed in a standardized fashion with a computer assisted protocol. This study showed that there was no significant predictive epidemiological variable on the results of the ETT. However, it was found that there was statistically significant difference between the peak exercise time of males and females undergoing the ETT.
This study was done to determine the prevalence of dental anomalies and facial profile abnormality and its association with the non-syndromic cleft lip and palate (CLP) as compared to the non-cleft children. A comparative cross sectional study was conducted where the case group consist of 98 non-syndromic CLP childrenunilateral (UCLP) and bilateral (BCLP) who attended the Combined Clinic at Kota Bharu Dental Clinic (KBDC) while the comparison group comprised of 109 non-cleft children who attended the outpatient clinic at KBDC. Their ages were between 3 to 12 years old. Clinical oral and facial profile examinations were carried out to look for dental anomalies (morphology, number and alignment of teeth)and facial profile abnormality. The prevalence of anomalies in morphology of teeth in CLP (24.5%) and non-cleft (10.1%), number of teeth in CLP (44.9%) and noncleft (7.3%), mal-alignment in CLP (79.6%) and non-cleft (27.5%) and facial profile abnormality in CLP (26.5%) and non-cleft (9.1 %). There was a significant association between CLP and anomalies in morphology, number, mal-alignment and abnormality in facial profile; (p < 0.05). Therefore, there was a high prevalence and risk of dental anomalies and facial profile abnormality in the CLP children compared to the non-cleft children.
The Malay version of the Medical Outcome Study (MOS) Social Support Survey was validated among a sample of postpartum Malay women attending selected health centers in Kedah, North West of Peninsular Malaysia. 215 women between 4 to 12 weeks postpartum were recruited for the validation study. They were given questionnaires on socio-demography, the Malay-versions of the MOS Social Support Survey, Edinburgh Postnatal Depression Scale (EPDS) and the 21-items Beck Depression Inventory-II (BDI-II). 30 of the women, who were bilingual, were also given the original English version of the instrument. A week later, these women were again given the Malay version of the MOS Social Support Survey. The scale displayed good internal consistency (Cronbach’s alpha = 0.93), parallel form reliability (0.98) and test-retest reliability (0.97) (Spearman’s rho; p
MeSH terms: Demography; Depression; Female; Humans; Language; Malaysia; Psychiatric Status Rating Scales; Surveys and Questionnaires; Social Support; Reproducibility of Results; Outcome Assessment (Health Care); Depression, Postpartum; Multilingualism; Postpartum Period
Increased international collaboration in clinical trials has created a need for cross culturally valid instruments to assess the quality of life and behavioural disorders. Cross cultural studies of depressive symptomatology, in particular, must be preceded by an exhaustive study of the psychometric properties of the instruments to ensure the validity of the comparison. In this article, we examined the validity, reliability and factor structure of the Malay version of the Beck Depression Inventory II (BDI-II) among Malay postpartum women attending selected health centres in Kedah, North West of Peninsular Malaysia. Our findings indicated that the current version of the BDI-II is psychometrically strong and appropriate for use in assessing depressive symptomatology among this group of women.
MeSH terms: Problem Behavior; Mental Disorders; Cooperative Behavior; Cross-Cultural Comparison; Depression; Female; Humans; Malaysia; Personality Inventory; Psychiatric Status Rating Scales; Psychometrics; Quality of Life; Reproducibility of Results; Postpartum Period
Many published studies that examined the effect of lead exposure on neurobehavioral performances were conducted in confined manufacturing environment with low to moderate blood lead levels as a marker of exposure. This study was conducted in a general environmental setting with very low exposure intensity and blood lead levels. The objective of the study was to determine the effect of very low blood lead levels (below 10 µg/dl) on the neurobehavioral performances of policemen in Kota Bharu, Kelantan. The study, conducted between August 25th and October 20th 2001, was cross-sectional in design and comprised of 89 policemen working in Kota Bharu district. The lead concentration of venous blood was determined using graphite furnace absorption spectrometer. We assessed neurobehavioral performances using the WHO Neurobehavioral Core Test Battery (NCTB). The mean blood lead concentration was 2.5 + 1.0 mg/dl. Among the seven tests performed, the positive effect of blood lead on Benton visual retention was not significant after controlling for the confounding effect of smoke-dose. This study suggested that very low blood lead levels have no significant effects on the neurobehavioral performances. Therefore, more studies with blood lead levels below the recommended environmental limit of 10 mg/dl, as recommended by Centers for Disease Control (CDC), be conducted in order to justify that limit.
MeSH terms: Attention; Centers for Disease Control and Prevention (U.S.); Cross-Sectional Studies; Graphite; Neuropsychological Tests; Smoke; Tobacco; Work
A case of a 53-year old-single, Kelantanese lady with a diagnosis of paranoid schizophrenia for 28 years is reported with aims to illustrate the influence of life experiences particularly based on education and intelligent on delusion illustrate the evolving nature of the complexity of delusions as well as to show the importance of documentation in psychiatric practice. We concluded that this patient had used defense mechanism of suppression, reaction formation and persecution throughout her delusion. The final persecutory delusion evolved through series of transformation via object of admirations. We postulated that in-depth emotional insight about effects of schizophrenia might have contributed to her self-reflection that have made her frustrated with her poor achievement in life.