Over the past century, the demand for petroleum products has increased rapidly, leading to higher oil extraction, processing and transportation, which result in numerous oil spills in coastal-marine environments. As the spilled oil can negatively affect the coastal-marine ecosystems, its transport and fates captured a significant interest of the scientific community and regulatory agencies. Typically, the environment has natural mechanisms (e.g., photooxidation, biodegradation, evaporation) to weather/degrade and remove the spilled oil from the environment. Among various oil weathering mechanisms, biodegradation by naturally occurring bacterial populations removes a majority of spilled oil, thus the focus on bioremediation has increased significantly. Helping in the marginal recognition of this promising technique for oil-spill degradation, this paper reviews recently published articles that will help broaden the understanding of the factors affecting biodegradation of spilled oil in coastal-marine environments. The goal of this review is to examine the effects of various environmental variables that contribute to oil degradation in the coastal-marine environments, as well as the factors that influence these processes. Physico-chemical parameters such as temperature, oxygen level, pressure, shoreline energy, salinity, and pH are taken into account. In general, increase in temperature, exposure to sunlight (photooxidation), dissolved oxygen (DO), nutrients (nitrogen, phosphorous and potassium), shoreline energy (physical advection—waves) and diverse hydrocarbon-degrading microorganisms consortium were found to increase spilled oil degradation in marine environments. In contrast, higher initial oil concentration and seawater pressure can lower oil degradation rates. There is limited information on the influences of seawater pH and salinity on oil degradation, thus warranting additional research. This comprehensive review can be used as a guide for bioremediation modeling and mitigating future oil spill pollution in the marine environment by utilizing the bacteria adapted to certain conditions.

The mass production and consumption of plastics have serious effects on the environment, human health, and livelihood. Hence, global efforts to reduce plastic generation must be realized. This study aimed to determine the prevalence of microplastics in mangrove sediments of Cabadbaran, Buenavista, and Nasipit in Butuan Bay, Philippines. Seventy-two (72) microplastic particles were extracted from mangrove sediments dominated by fibrous type (71%) and blue (35%) as the most common color. Attenuated total reflectance–Fourier transform infrared (ATR–FTIR) spectroscopy was used to assess the polymer type of microplastics. Results reveal a total of six polymer types including high-density polyethylene, low-density polyethylene, polyethylene terephthalate, ethylene-vinyl acetate, polyamide, and polypropylene, with the latter comprising 39% of samples, the highest among the extracted particles. Overall, Nasipit (71.1/kg) obtained the highest microplastic density followed by Buenavista (48.9/kg) and Cabadbaran (40.0/kg). These data will serve as a piece of baseline information in crafting important environmental policies to address plastic pollution issues in the area. Long-term studies are recommended to better understand, monitor, and prevent further microplastic pollution in Butuan Bay.