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Fattorini

introducing additional chemicals or disturbances representing a promising practice for more effective and
to the ecosystem; however, it can be a very slow less invasive marine ecosystem recovery. 107
process, potentially taking years or decades to exhibit Physical removal, involving the direct mechanical
a significant reduction of the contamination levels and removal of spilled material from the environment,
extension. Natural attenuation is generally unsuitable represents the ultimate available means where other
for highly toxic or very large spills where immediate systems cannot completely remove hydrocarbons
intervention may be required. 25 from marine ecosystems. Physical removal techniques
Bioremediation represents the primary active include manual cleanup of shorelines (using shovels,
strategy to mitigate the effects of oil spills. This rakes, absorbent materials), use of absorbents on water,
approach leverages microorganisms (bacteria and and large-scale mechanical recovery operations. These
fungi) to break down hydrocarbon contaminants practices can quickly remove large quantities of oils,
into less harmful substances, such as carbon dioxide substantially reduce pollution, and prevent further
and water. Among the commonly used techniques, spread. However, they are highly labor-intensive and
bioaugmentation involves the introduction of specific, costly, generating significant volumes of waste that
pre-selected microorganisms, often specialized for require specialized disposal. It can disrupt sensitive
degrading particular hydrocarbons, to the contaminated habitats during cleanup operations and potentially harm
site to enhance biodegradation rates. On the contrary, workers exposed to toxic substances through contact or
the biostimulation approach focuses on adding inhalation. 43,82
nutrients (e.g., nitrogen, phosphorus) or oxygen to the Responding to marine hydrocarbon contamination
contaminated environment to stimulate the growth and requires a dynamic and adaptable approach. No single
activity of indigenous, naturally occurring, hydrocarbon- technique provides a universal solution; instead,
degrading microorganisms. Bioremediation practice a combination of containment, monitoring, and
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is an environmentally friendly approach as it utilizes remediation strategies is typically employed, tailored
natural processes and can potentially lead to the complete to the specific characteristics of each spill. Ongoing
degradation of pollutants rather than just their transfer. research and technological advancements continue
However, the process can be slow, and its effectiveness to refine these methods, striving for more effective,
highly depends on environmental conditions, such as efficient, and environmentally sound responses to
temperature, pH, salinity, and nutrient availability. safeguard marine ecosystems.
In addition, the success of bioaugmentation can be
limited by the ability of introduced microorganisms to 7. Challenges, recommendations, and future
compete with native populations. Biostimulation was research prospects
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applied extensively after the Exxon Valdez oil spill in
Alaska. Fertilizers were sprayed on oiled beaches to Hydrocarbon contamination in the marine environment
provide essential nutrients (nitrogen and phosphorus) represents a significant global threat, affecting
to naturally occurring hydrocarbon-degrading bacteria, ecosystems, human health, and economic activities.
significantly accelerating the breakdown and removal A key challenge lies in accurately quantifying the
of residual oil from the affected shorelines. 26,27 pervasive and often underestimated cumulative load of
Among the bioremediation techniques, promising hydrocarbons from chronic sources, such as shipping
attempts have recently been investigated using discharges, urban runoff, and atmospheric deposition,
engineered microorganisms. This practice can represent which can have insidious long-term impacts beyond
an improved approach to cleaning up marine oil spills. acute spill events. Furthermore, the efficacy and
Modified bacteria and fungi can accelerate their oil- potential toxicity of chemical dispersants, particularly
degrading pathways, making them more efficient at with viscous oils or in deep-water applications, remain
breaking down complex hydrocarbons into harmless debated. Future research could include a systematic
substances, such as carbon dioxide and water. These review of the different types of chemicals used and their
designed microbes can be optimized for specific oil short- and long-term effects on marine ecosystems.
components or environmental conditions, such as Remediation efforts, such as bioremediation,
temperature and salinity. When deployed, they rapidly face limitations in speed and effectiveness due to
proliferate and consume the oil, significantly reducing environmental variability and competitive microbial
the environmental impact of spills and offering dynamics. The long-term recovery of affected
a sustainable alternative to chemical dispersants, ecosystems can also span decades, especially for

Volume 22 Issue 6 (2025) 40 doi: 10.36922/AJWEP025290224