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Hydrocarbons in seawater

Affected species experience impaired growth and to the coast. 88-90 As mentioned above, regional variability
reproduction, immune suppression, developmental significantly modulates hydrocarbon dynamics
abnormalities, and behavioral changes. Long-term in marine environments, influencing oil density,
ecosystem disruption, including habitat degradation of dispersion, spreading, and emulsification. Based on this
vital coastal areas, such as mangroves and coral reefs, perspective, there is no unified fate of hydrocarbons in
and bioaccumulation within the food web, severely the oceans, as cold, temperate, or tropical environments
threatens ecosystem health and biodiversity. Species, can significantly alter the extent and speed of the
such as seabirds, marine mammals (e.g., dolphins, chemical–physical and biological phenomena at play.
1,2
whales), sea turtles (e.g., Kemp’s ridley), fish, deep-sea Considering the numerous variables in play, Figure 3
corals, and various invertebrates and their larvae are proposes a series of model mechanisms of the main
particularly vulnerable to these persistent effects. 11,44-46 processes triggered by the presence of hydrocarbons in
the sea, considering that such phenomena may deviate
4. Fate of hydrocarbons in seawater from those described, depending on the existence of
particular and peculiar environmental conditions and
The fate of hydrocarbon mixtures in the sea, whether events.
from natural or anthropogenic sources, is characterized In the open ocean, the oil on the water surface
by numerous and complex chemical–physical processes undergoes spreading, a rapid process driven by
and interactions with living organisms. These processes gravity and surface tension, forming thin films known
are strongly influenced by the characteristics of the as slicks. Large oil slicks can float and move on the
hydrocarbon mixtures, such as density, viscosity, surface waters. Wave motion and currents significantly
volatility, and composition, but also by environmental affect the mobility, transport, and dispersion of such
conditions and variables, such as temperature, salinity, oil slicks, promoting rapid spread and drifting. The
90
wave motion and currents, wind intensity, and proximity simultaneous action of the waves and the wind plays

Figure 3. Fate of hydrocarbons in the sea. A range of potential phenomena associated with the presence
of hydrocarbons in marine ecosystems, including transport and spread of oil slicks at the water surface,
aerosol formation and atmospheric transport and deposition, dissolution and collapse in the water column,
interaction and compartmentalization in sediments, and threats to various marine species, including
invertebrates, vertebrates, and seabirds. Image created by Daniele Fattorini with Microsoft Office 365
enterprise, PowerPoint v.2504.

Volume 22 Issue 6 (2025) 31 doi: 10.36922/AJWEP025290224