Emerging pollutants (EPs), also known as micropollutants, have been a major issue for the global population in recent years as a result of the potential threats they bring to the environment and human health. Pharmaceuticals and personal care products (PPCPs), antibiotics, and hormones that are used in great demand for health and cosmetic purposes have rapidly culminated in the emergence of environmental pollutants. EPs impact the environment in a variety of ways. EPs originate from animal or human sources, either directly discharged into waterbodies or slowly leached via soils. As a result, water quality will deteriorate, drinking water sources will be contaminated, and health issues will arise. Since drinking water treatment plants rely on water resources, the prevalence of this contamination in aquatic environments, particularly surface water, is a severe problem. The review looks into several related issues on EPs in water environment, including methods in removing EPs. Despite its benefits and downsides, the EPs treatment processes comprise several approaches such as physico-chemical, biological, and advanced oxidation processes. Nonetheless, one of the membrane-based filtration methods, ultrafiltration, is considered as one of the technologies that promises the best micropollutant removal in water. With interesting properties including a moderate operating manner and great selectivity, this treatment approach is more popular than conventional ones. This study presents a comprehensive summary of EP’s existence in the environment, its toxicological consequences on health, and potential removal and treatment strategies.

Nanomaterials, classified as emerging pollutants that are toxic to the environment, are known to bioaccumulate across different trophic levels in the aquatic ecosystem. This study therefore investigates the distribution of silver and silver nanoparticles (AgNPs) in the aquatic environment of Skudai River, Johor, Malaysia. Water, sediment, plant, and fish samples were collected seasonally along four sites along Skudai River between May 2018 and April 2019. All samples were subjected to Ag analysis using an inductively coupled plasma mass spectrometer (ICP-MS). The analysis demonstrated that the concentration of Ag detected in water samples ranging from 0.001 to 0.505 mg/L was the lowest, whereas in the plants, 0.235 to 4.713 mg/kg of Ag was quantified. The upper sediments contained 0.036 to 28.115 mg/kg of Ag, whilst fish samples presented the highest accumulation of Ag, averaging between 9.144 and 53.784 mg/kg of Ag. Subsequently, the formation of silver nanoparticles was further proven by TEM-EDX analysis, where the detected size of AgNPs ranged from 20 nm to 35 nm. The overriding conclusion implied by bioaccumulation factor (BAF) and biota–sediment accumulation factor (BSAF) calculations suggested that Skudai River was indeed polluted by Ag and AgNPs. The values obtained stipulated that silver accumulation is occurring at an alarming rate and could therefore endanger fish consumers.

Biomass-such as cellulose is one of the most common abundant organic materials on the Earth. Biomass has carbon chain that could be an excellent choice for the fabrication of carbon materials. Cellulose nanocrystal is nano-sized cellulose and could become the potential source in fabricating carbon nanodots that are affected by pyrolysis temperature. In fact, the size and temperature are essentially important to synthesize the carbon nanodots. This research is contributed to synthesize this material, and to investigate the effect of temperature. The percentage of cellulose nanocrystals and carbon nanodots obtained are less than 50%. Carbon nanodots are synthesized by pyrolysis method and cellulose nanocrystals are fabricated by membrane method. TEM analysis shows that cellulose nanocrystals are nano-sized. Under UV light source, the samples show fluoroscencing colours i.e. blue to green. From this research it can be concluded that the temperature affects the characteristics of carbon nanodots produced by pyrolysis method.

The synthesis of modified carbon dots (N-CDs) from nanocrystalline cellulose, as the carbon source, with the combination of urea and ethylenediamine, as nitrogen dopant agents, was successfully carried out by pyrolysis at 300°C. The N-CDs dispersed in both ethanol and distilled water generated bright blue fluorescent color under a UV lamp at 365 nm wavelength with a 29% quantum yield value. FTIR analysis confirmed that the surfaces of carbon dots were modified by amine and N-doped groups on the carbon ring structure and the data from the UV-VIS spectrum also showed that assumption. Produced N-CDs had a size distribution of 2-5 nm with an average diameter of around 3.4 nm. The ability of N-CDs as a detector was explored from the fluorescence quenching by Hg2+ ions, in which it reached 40%. The determination of Hg2+ could be completed in 10 min with a wide linearity range from 0-100 µM and a detection limit of 59 µM by the static quenching process.

Oil Palm Empty Fruit Bunches (OPEFB) are abundant organic waste that contains cellulosic compound. This study aims to fabricate PCL/cellulose nanofiber bionanocomposites from OPEFB and to analyze their thermal and mechanical properties. Nanofiber cellulose with an average size of 32 nm was isolated from OPEFB by using alkaline condition and mechanicalmethods. This was proven by the presence of functional group analysed from the FT-IR spectrum and morphological analysis with TEM. Bio-nanocompositePCL/cellulose nanofiberfrom OPEFBwas further made in several variations, namely: 100%: 0%, 90%: 10%, 80%: 20%, 70%: 30%, 60%: 40%. The samples were then tested for their mechanical properties with tensile test to determine optimal results and the optimal ratio was 80%: 20% w/v, with tensile strength of about 8,830 Mpa and 40,78% strain. This is also proven by morphological analysis using SEM which shows a flat and homogeneous surface. The optimal sample was thermally analyzed using DSC and it is showed that the resulting bionanocomposite decomposed (T_d) at 513.10°C through an exothermic process with a heat of 414.08 J/g.