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Hydrocarbons in seawater

Commonly used dispersants sometimes have Chemical analysis is time-consuming and requires
complex formulations, for which details on the specialized laboratory equipment and highly trained
involved chemical species and their concentrations personnel for sample analysis and results interpretation.
are not always available. Furthermore, over the years, Following the Exxon Valdez oil spill (1989), extensive
various substances have been progressively abandoned chemical analysis of hydrocarbon levels in water,
and replaced with new products, making it difficult to sediments, and marine organisms was conducted
compare their efficiency, benefits, and adverse effects, for decades to track the persistence and spread of
especially considering that the contexts of use often contaminants, providing critical data for understanding
represent unique conditions. The regulatory framework long-term ecological damage and recovery rates. 26,77
on a global scale is therefore extremely diverse and This data type also constitutes a fundamental scientific
subject to change over time. Further in-depth analysis reference for planning monitoring plans and subsequent
of this topic is necessary. environmental investigations. 105
Following the initial containment works, effective In addition to chemical characterization,
spill response relies on robust monitoring to track the biomonitoring plays an immediate and central role.
spill’s trajectory, assess its environmental impact, and This approach uses living organisms as indicators of
guide remediation efforts. Using airborne or satellite- environmental health and pollutant exposure. It assesses
based sensors to detect, map, and track oil spills, remote physiological changes, bioaccumulation of pollutants
sensing may provide a broad, synoptic overview of in tissues, or impacts on population dynamics and
the spill’s extent, movement, and changes over time, community structure. 49,50,102,106 Biomonitoring provides
crucial for large-scale incidents. Among the remote an integrated measure of contaminant effects over time,
sensing technologies, synthetic aperture radar can reflecting the bioavailability of pollutants to organisms
penetrate cloud cover, offering data in adverse weather rather than just their environmental concentration.
conditions, while conventional optical sensors are Biomonitoring can identify subtle ecological impacts
ineffective in darkness or limited lighting scenarios. In that are not immediately apparent through chemical
general, remote sensing enables rapid assessment and analysis alone. Given that the response of biological
strategic planning of response operations. However, indicators can be slow to manifest, biomonitoring often
resolution can be restricted, making detecting very thin requires long-term planning. Establishing causality
slicks or detailed features difficult. Interpretation of between observed biological effects and specific
data requires specialized expertise, and remote sensing contaminants can be complex, requiring a thorough
primarily provides surface-level information, not real- understanding of baseline biological conditions. Thus,
time subsurface dynamics. Satellite imagery and aerial the success of a biomonitoring plan depends on a
surveillance were valuable during the Deepwater robust and solid scientific reference base regarding the
Horizon oil spill for tracking the massive oil slick, stress-related biological effects of sentinel organisms
predicting its movement, and directing response vessels and in-depth knowledge related to their sensitivity
and booming operations to critical areas. 104 and responsiveness. 105,106 After the Prestige oil spill
Chemical analysis of environmental samples (2002) off the coast of Spain, biomonitoring studies on
(water, sediment, biota) is a fundamental and central commercially important shellfish and fish populations,
key to environmental monitoring plans, identifying which continued for many years, have been fundamental
specific hydrocarbon compounds, determining their for understanding the bioaccumulation trends in
concentrations, and assessing their degradation products organisms’ tissues, demonstrating the long-term impacts
and potential toxicity. Chemical determinations may on marine food webs and the fishing industry. 27,80-82
provide precise and accurate quantitative and qualitative Various remediation strategies aim to clean up the
data related to pollutant characteristics, concentrations, spilled material and restore the affected environment
and spatial distribution, which are essential for risk to pristine conditions. Natural attenuation includes a
assessment, pollutant fate comprehension, and long- series of intrinsic physical, chemical, and biological
term monitoring of environmental recovery. The processes that reduce pollution over time without
possibility of periodically monitoring over time and direct human intervention. These processes include
integrating data relating to abiotic matrices (water and dispersion, dissolution, volatilization, photo-
sediments) and the tissues of bioindicator organisms oxidation, and biodegradation by naturally occurring
can provide an integrated picture of the degree of microorganisms. Natural attenuation is highly
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contamination and related temporal trends. 49,50,105 cost-effective and minimally invasive, as it avoids

Volume 22 Issue 6 (2025) 39 doi: 10.36922/AJWEP025290224