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Hydrocarbons in seawater

such as fuels or other mixtures, always cause harmful gamete development, fertilization success, and larval
effects. 11,32,52 The complexity of the mixtures and viability across a wide range of taxa. 43,82 This can
the variety of products potentially involved often lead to reduced spawning success, decreased fertility,
make it difficult to predict the extent and severity and compromised recruitment, threatening population
of contamination and the possible short- and long- stability. Developmental abnormalities, such as fish
term effects. Furthermore, as previously described, larvae and invertebrate embryos, are frequently
the specific characteristics of the area affected by the observed in early life stages, manifesting as skeletal
contamination and various environmental variables can deformities, cardiovascular dysfunction, and impaired
drastically influence the severity and persistence of the organ development. 11,32 The aryl hydrocarbon receptor
disturbances caused by the presence of hydrocarbons in pathway, involved in xenobiotic metabolism, is
the sea. 1,2 often implicated in these developmental toxicities.
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In crude oil contamination, especially if characterized Furthermore, hydrocarbons can induce immune
by high viscosity and density, the most immediately suppression, making organisms more susceptible
noticeable and significant damage is predominantly to diseases, parasites, and environmental stressors,
physical. Seabirds and marine mammals can become weakening population resilience. 11
covered in oil, which adheres to their skin or plumage, Hydrocarbons, especially persistent and lipophilic
forming a barrier and causing suffocation, inability compounds, such as PAHs, exhibit tendencies for
to move or fly, impairment of various physiological bioaccumulation in various vertebrate and invertebrate
functions, and compromising the ability to forage aquatic species. 15,62 Higher organisms generally possess
and reproduce. Animals relying on fur or feathers for the enzymatic pathways capable of metabolizing
insulation also suffer severe hypothermia when their aliphatic and aromatic hydrocarbons; therefore, it is not
protective layers are matted by oil, compromising their uncommon to find higher levels of bioaccumulation in
ability to regulate their body temperature, and causing benthic invertebrate organisms from contaminated areas
fatigue, starvation, and even death. In intertidal areas, rather than in fish. On the other hand, it is known that
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the stranding of crude oil slicks can also cover the some multienzyme systems capable of transforming
surfaces of numerous species of mollusks (mussels, specific xenobiotics (i.e., cytochrome P450) often
oysters, gastropods,), crustaceans (crabs, hermit crabs, produce products that express greater toxicity.
barnacles,), echinoderms (sea urchins), and other Consequently, vertebrate organisms in contaminated
benthic invertebrates, compromising many of their areas may manifest notable adverse effects even without
vital functions and the capability to move, impeding high levels of bioaccumulation. As a result of these
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respiration, feeding, and waste elimination. 11,32,52,97 mechanisms, and given that hydrocarbon mixtures can
These physical effects are accompanied by undergo biodegradation, their bioaccumulation can be
toxicological damage. One primary mechanism is transferred into food chains, although biomagnification
narcosis, particularly by low molecular weight aromatic is generally not observed. Given the high lipophilicity
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hydrocarbons (e.g., benzene, toluene, ethylbenzene, of the hydrocarbon mixtures, higher animals, such
xylenes, naphthalene, and derivatives), which are highly as marine mammals can be subject to an elevated
soluble and volatile. These compounds can rapidly bioaccumulation rate in tissues rich in body fat. 15,62
penetrate biological membranes, interfering with cellular Hydrocarbon pollution may disrupt entire marine
processes, disrupting nerve impulse transmission, and ecosystems. Habitat degradation occurs when sensitive
causing central nervous system depression. This leads environments, such as coral reefs, mangrove forests,
to disorientation, paralysis, and ultimately death in and salt marshes are directly contaminated, leading
affected marine life. Even at sublethal concentrations, to structural complexity and functionality loss. For
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hydrocarbons may inflict profound chronic sublethal example, corals are highly sensitive to oil, which can
effects, impairing the health and viability of marine cause bleaching, necrosis, reduced growth rates, impaired
populations. Physiological stress is a common response, reproduction, and altered larval settlement. Chronic
characterized by elevated metabolic rates, disrupted exposure can decrease their resilience to environmental
osmoregulation, and altered energy allocation, as stressors, such as ocean acidification and warming. Given
organisms expend energy on detoxification and repair the close ecological relationship between species, the
rather than essential life processes. Reproductive entire coral reef ecosystem could be compromised in a
impairment is a particularly concerning effect, with cascade. Mangroves are also critically important coastal
hydrocarbons interfering with hormone regulation, habitats that are highly susceptible to oiling. Oil can

Volume 22 Issue 6 (2025) 35 doi: 10.36922/AJWEP025290224