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Pasir Pandak Beach is close to human settlements, resorts, and food stalls. It becomes a place for gathering of beachgoers especially during weekend. As a result, the beach became polluted with rubbish, particularly plastics (e.g., macro- and micro-plastics). Hence, this study was done to determine the occurrence of macro- and micro-plastics on the Pasir Pandak Beach, Kuching, Sarawak, Malaysia. Transect quadrat was used during the samples collection on the beach. The samples were then undergone the wet peroxide oxidation, filtering and classifying under dissecting microscope. Macroplastics were isolated for ATR-FTIR and SEM analyses, while microplastics were separated according to their sizes, colors, and types. Approximately 101.70 items/m2 of macro-plastics and 1084 items/m2 of micro-plastics were found in this study. Clean Coast Index (CCI) was also estimated and the calculated CCI value obtained was >20, which indicated as extremely dirty beach. Fragments of carpet/canvas/mat and hardware crate/item were the most abundance macroplastics found, followed by plastic ropes/fishing lines and bottle caps. HDPE, PES, PP, and PS were the main identified polymers. Fibers, filaments, fragments, and foams were identified for micro- and macro-plastics. Microplastics with smaller sizes of 0.25-0.50 mm were available abundantly and they comprise 63.47 % of the total microplastics found. Clear/white, black, and blue were the main colors for microplastics. SEM images presented that those adhering particles, grooves, pits, fractures, and flakes were the common patterns of degradation. No relationship was apparent between macroand micro-plastics at each station. The abundance of macro- and micro-plastics showed that they were mainly controlled by the land-based input. As Pasir Pandak beach is busy with local communities and beachgoers, the presence of macro- and micro-plastics on the beach posing a severe threat for marine environment, thus further studies on the behavior of this emerging pollutant from beach to the seas are necessary. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) and lead (Pb) are toxic heavy metals with a growing appeal for study due to their ability to bioaccumulate in fish which may pose threat to human health through fish consumption. This study reported the concentration of Cd and Pb in water, sediment, fish, and prawn in Santubong Estuary, Malaysia. Water, sediment, fish (Arius maculatus) and prawn (Fenneropenaeus merguiensis) samples were collected from three rivers namely Buntal, Penambir and Demak. These samples were digested and analyzed using Flame Atomic Absorption Spectrophotometer (FAAS) for the heavy metal contents. The potential ecological and human health risks were assessed by using the bioaccumulation factor (BAF), Geoaccumulation Index (Igeo), Enrichment Factor (EF), Provisional Tolerable Weekly Intake (PTWI), Health Risk Index (HRI) and Health Index (HI). Cd and Pb concentrations in water were within the permissible limits but were above the acceptable limits in sediment as recommended by WHO. The concentration of Cd in A. maculatus was (0.10 - 0.13 mg/kg) while the concentration of Cd in F. merguiensis was (0.11 - 0.15 mg/kg), and these values were below the safety limits set by FAO/WHO and MFA. The concentration of Pb in A. maculatus (0.19-1.46 mg/kg) was also below the safety limits; however, the concentration of Pb in F. merguiensis (1.35-2.97 mg/kg) surpassed these safety limits. The Igeo values were less than one, and EF values ranged between 5 and 20, suggesting that this area is polluted with heavy metals. The BAF values for Cd (0.001 - 0.002 mg/kg) and Pb (0.003 - 0.040 mg/kg) showed that there might be an appreciable chance of bioaccumulation of heavy metals in the fish and prawn. The PTWI of prawn was slightly above the acceptable PTWI of Pb recommended by FAO/WHO (2016). Comparison with the safety limits showed that the continuous consumption of these fish and prawn for a long period would impose bad impacts on health. HRI and HI in both organisms were greater than one, indicating that there were possible adverse effects. Therefore, close monitoring of this area is recommended to minimize the risks of aquatic organism consumption. [ABSTRACT FROM AUTHOR]

Mass mortality of fish (∼8,500 fishes), mainly Oreochromis placidus, was noted in a man-made lake located at Kuching, Sarawak (Malaysia). A field investigation was conducted to collect water samples and fishes. Patches of discoloration in brick red were observed in the lake and clear oil layer was found on the surface of the water. Microscopic observation and enumeration of the water samples showed that the plankton composition was dominated by a green algal species Botryococcus sp., with the colony densities ranging 1.2×10³ –7.4×106 colonies L−1 . Detailed morphological assessment by light microscopy revealed the dominant species as Botryococcus braunii Kützing. Molecular characterization using an rDNA marker further supported the species identity as B. braunii in the L race. Fish gill observation showed that cells of B. braunii and the oily substances were found in the dead fish gills. The race-L B. braunii bloom was reported, for the first time, to be associated with a fish kill event in a freshwater lake in Malaysia and confirmed the species as one of the algal types causing harmful effects to the environment. [ABSTRACT FROM AUTHOR]

This study analyzed the levels of cadmium (Cd), copper (Cu), and zinc (Zn) by the flame atomic absorption spectrophotometer (FAAS), in the muscle tissues, exoskeletons, and gills from freshwater prawn (Macrobrachium rosenbergii) (n = 20) harvested from natural habitat in Kerang River, Malaysia on 25th November 2015. Significant increase of the metals level in muscle tissue and gill (r > 0.70, p < 0.05) were observed with increase in length except for Cu in gills. No relationship was found between metals level in exoskeleton and length. The concentrations of Cd, Cu and Zn were significantly higher (p < 0.05) in males (muscle tissues and exoskeleton) except for Cd in exoskeleton. In gills, only Cu was significantly higher (p < 0.05) in female than male. All samples contained metals below the permissible limit for human consumption (i.e., Cd < 2.00 mg/kg; Cu < 30.00 mg/kg; Zn < 150 mg/kg). Annual metals monitoring in prawn and environmental samples is recommended to evaluate changes of metals bioaccumulation and cycling in the system, which is useful for resources management. [ABSTRACT FROM AUTHOR]

The microplastic ingestion of marine invertebrates around ASEAN countries namely, Indonesia, Malaysia, Philippines, Thailand, and Vietnam were reviewed. The review involves locations, species, concentration of microplastics, as well as dominant colors and types of microplastics. The most studied species was Perna viridis. The highest concentration of microplastic was found in Laevistrombus turturella with 628 ±191.93 particles/individual. Black was the most common dominant color of microplastics and fiber was the most common type of microplastics found in the marine invertebrates. Two lab-based studies of microplastic ingestion in Acropora formosa and Perna viridis had shown detrimental effects of microplastics. The challenges of microplastic ingestion study around ASEAN was the possibility of microplastic entering seafood food security in both wild and farmed populations, as well as the probable collapse of the coral reef ecosystem. [ABSTRACT FROM AUTHOR]