Marfiah Ab. Wahid

Study of water quality at mangrove island: Case study of Carey Island

This paper reviews on the water quality for Carey Island which is one of the mangrove islands in Malaysia. The mangrove area has vital functions of its mangrove tress. In order to control and protect the level of contamination at this area, a study on water quality has been carried out. Three rivers that selected as a point of study are Air Hitam, Judah and Keluang River. The parameters tested for the water quality are Temperature, pH, Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Turbidity, Total Suspended Solid (TSS), Total Organic Carbon (TOC) and Ammoniacal Nitrogen (NH3-N). The parameters were tested by in-situ and laboratory testing. Finally, it is found that the Air Hitam, Judah and Keluang rivers are experiencing contamination and pollution problems. Water Quality Index calculation shows that all the rivers fall under Class III River category. Air Hitam River has the worst quality followed by Keluang River and Judah River

Trend of Total Phosphorus on Total Suspended Solid Reduction in Constructed Wetland Under Tropical Climate

Constructed wetland has the potential to provide significant treatment for quality of stormwater runoff, especially in total suspended solid and total phosphorus concentration. The aim of this research is to investigate the trend of total phosphorus on total suspended solid reduction in constructed wetland in order to enhance the urban stormwater quality. This study was conducted in actual constructed wetland located in Universiti Sains Malaysia (USM) Engineering Campus, Nibong Tebal, Penang, Malaysia. The water samples were taken using grab sampling method from 14 sampling stations for seven months based on 14 stormwater events. The results showed a positive value of Pearson’s r as the total suspended solid had a positive correlation with the total phosphorus approximately, r = 0.78, which can be considered a large effect on the reduction trend. The coefficient of determination, R 2 = 0.93, was obtained from the relationship between total suspended solid and total phosphorus. Thus, the decreasing trend of total suspended solid concentration also showed the decreasing concentration of total phosphorus. The appropriate selection of macrophyte, water depth, and hydraulic residence time are vital to enhance the stormwater quality before discharge to the receiving water body.

Adaptation of NoV LAMP Primers by PCR for Highly Sensitive Detection of Noroviruses in Water

A fast and highly sensitive detection of noroviruses was established by Reverse Transcriptase PCR amplification using primers adapted from loop-mediated isothermal amplification (LAMP) of noroviruses (RT-L-NoV PCR amplification). The amplification was carried out in 30-min early incubation in 50 °C for reverse transcription activity and further 35 PCR short cycles for total finishing time within 60 min with no cross-reactivity with other common environmental species and strains. The LOD of this method was 10−15 × 100 ng/ulor 1zg/ul of pIDTSMART-NoV gene per reaction which is reported to be the highest sensitivity conventional PCR-based detection method for noroviruses. These early findings give hope for a potentially useful RT-L-NoV PCR amplification assay for a highly sensitive detection of NoV genomes especially in diluted concentration sample like water.

Antibiotic Resistance Bacteria in Coastal Shrimp Pond Water and Effluent

The rapid growth of shrimp farm activities began since last 40 years. It is due to high demands and can generate economy to the country. In Malaysia, thousands tonnes of shrimp were produced every year for local demand and export as well. However high demand in this industry, causes problem of water pollution in shrimp ponds which subsequently contaminated discharge from the pond due to presence of bacteria. In this study, it was found that shrimp farm water and effluent containing pathogenic bacteria which is resistant to certain antibiotic. These antibiotic resistance bacteria could be harmful to human. Vibrio alginolyticus, Vibrio parahaemolyticus, Shigella flexneri and E. coli were detected in the water and effluent from the shrimp farm. Total of Vibrio in 3 and 6 months pond were higher than allowable limit, which is 1625 and 2650 cfu/ml, respectively. E. coli in this study was recorded at low concentration, however dramatically increased in 4 months pond (438 cfu/ml) before plunging to 13 cfu/ml in 6 months pond. It can be concluded that the higher number of pathogenic bacteria (>1000 cfu/ml of Vibrio) were detected in shrimp pond water and effluent can cause illness to human health.

Detection and Transportation of Nutrients and Pathogenic Bacteria in Kerayong River Water

Water is one of the most important sources of human life. Rainfall is abundant source that can provide water for human consumption. However, the clean water source cannot be relished, as a result of pollution caused by humans. Development and modernization cause water to become filthy and not suitable to be used directly and require rigorous treatment. Kerayong River that passes through residential and industrial area in Kuala Lumpur also became a victim of water pollution. 6 sampling points along the Kerayong River in this study showed the high rate of ammoniacal nitrogen and phosphorus in the river water, which is 6.92–10.83 mg/L and 2.22–3.53 mg/L, respectively. The presence of nitrate and nitrite concentration can also be detected from 0.09–0.22 mg/L to 0.05–0.17 mg/L, respectively. Pathogenic bacteria such as Salmonella, Shigella, E.coli, and Pseudomonas aeruginosa were detected in concentrations up to 173 cfu/ml in the river water, overcoming the limits. Although only in sampling points 1–4 could detect Vibrio spp. with low concentration, but it still needs to be concerned. Overall, the river water is not suitable for use directly without going through the proper water treatment process.

Stormwater Treatment Using Porous Rock Matrices

Stormwater carries a broad mix of toxic chemicals, bacteria, sediments, fertilisers, oil and grease to nearby water bodies, which makes it polluted for other use. Under Malaysia climate, abundance stormwater runoff can be collected, treated and then reused for other purposes depending on the treated water quality. For the purpose of the study, a site in UPM Serdang was identified and selected to house a treatment unit with stormwater feed system using porous rock matrices as treatment media. The rock matrix is originally used as landscape tool due to its aesthetic value. However, the porous nature of the rock matrix has potential to remove stormwater impurities via biological treatment. Thus, the objective of this study is to evaluate the treatment efficiency of the porous rock matrices as treatment media. The research methodologies involve design, build and commission of the treatment unit followed by water quality test for selected parameters. The treatment unit achieved the following removal efficiency for total suspended solid (TSS) (57–72 %), turbidity (15–87 %), colour (55–87 %) and dissolved oxygen (DO) (2–17 %). pH value shows an increasing trend of 7–40 %. Nevertheless, the result for total dissolved solid (TDS) and electrical conductivity (EC) fluctuates throughout the treatment process.

Detection of Pathogenic Bacteria in Flood Water

End of year, flood normally hits the eastern coast of the Peninsular Malaysia. The natural hazard usually causes property damage and loss of lives. However, pathogenic bacteria in flood water should be taken into account to ensure that it does not affect human health during flood. This study shows that three types of bacteria were found in flood water in Pahang. Shigella flexneri, Salmonella typhimurium, and Escherichia coli, which are pathogenic, can affect the human health if the hygiene factors are not taken care. E. coli was found in flood water with an average 671 cfu/ml. While Salmonella were found in Paloh Hinai, Kg. Batu Dua Belas, and Chini with 25, 50, and 38 cfu/ml, respectively. An average of 233 cfu/ml Shigella was found in flood water. Overall the flood water quality fulfilled the National Water Quality Standards for recreational use with body contact. However, more data of the actual flood situation are needed to be able to confirm the actual microbes present in flood water.

Evaluation on the treatment processes for pathogens removal in wastewater reclamation and reuse

This research focused on the investigation on the removal efficiency of pathogenic bacteria and human viruses to produce safe wastewater reclamation and reuse for agricultural purposes. Under existing wastewater treatment processes, only 1-2 logs removal could be achieved of various targets of pathogens. Therefore, further treatment was required to comply with the water reuse guideline established by World Health Organization (WHO). Investigations were conducted using model microorganisms to evaluate the performance of advance treatment technology including ultraviolet (UV) and ozonation (O3). A few logs reduction could be achieved with minimum dose of UV and ozonation. This research concluded that UV and ozonation could achieve 2-5logs pathogen removal for wastewater reclamation and reuse suitable for agriculture activity.

Study of bioindicator at mangrove island: Case study of Carey Island

This paper reviews on the bioindicator for Carey Island which is one of the mangrove islands in Malaysia. The bioindicator was used to assess the level of river pollution at Judah, Air Hitam and Keluang River rather than using normal test such as Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) tests. The bioindicators found at the sampling site were river crab, adult beetles and nymphs. By referring to the score sheet, the Biological Water Quality Index (BWQI) was calculated. As a result, the average BWQI value for all rivers indicated in range rather dirty. Meanwhile, the Chemical Water Quality Index (CWQI) shows that all the rivers were polluted in general.