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Fattorini

Figure 4. Photo-oxidation of hydrocarbons in the surface waters. Solar irradiation may produce photochemical
oxidation of aromatic hydrocarbons with the formation of sensitizing agents, which in turn promote the
photo-oxidation of the aliphatic components with the formation of aldehydes, ketones, and alcohols, that are
more soluble and potentially dangerous for fish species. Image created by Daniele Fattorini with Microsoft
Office 365 enterprise, PowerPoint v.2504.

mixtures, such as crude oil. Similarly, irradiation of and survival. Furthermore, some of these compounds can
alkylnaphthalenes in the presence of oil or the soluble be highly persistent, prolonging their detrimental impact
fraction of gasoline in seawater formed photo-oxidation on marine ecosystems. The combined effects of these
polar compounds, such as alcohols, aldehydes, acids, degradation byproducts contribute to altered community
and quinones. 38,93,94 structures, reduced biodiversity, and overall ecosystem
Biodegradation and photo-oxidation processes, while degradation. 95
seemingly beneficial in breaking down pollutants, can yield A highly relevant and timely aspect is the significant
byproducts that pose significant adverse effects on marine influence of climate change on marine hydrocarbon
organisms. Aerobic biodegradation can produce various dynamics. Ocean warming can increase the temperature
oxidized intermediates. While some are less harmful, and dispersion of oil, potentially speeding up evaporation
others, such as certain organic acids or partially oxidized and natural dispersion and increasing the toxicity of
PAHs, being more soluble than the original compounds, some oil components. Ocean acidification, resulting
can potentially enter biological compartments more easily from increased carbon dioxide absorption, might also
and exert greater toxicity, altering various physiological affect the efficiency of oil-degrading microorganisms.
functions, including reproduction, growth, and immune Furthermore, extreme weather events, such as stronger
response. Under anaerobic conditions, degradation storms and hurricanes, amplified by climate change,
95
pathways can generate hydrogen sulfide, which is highly pose a greater risk of damage to offshore oil and gas
toxic to many marine species, particularly those in benthic infrastructure, increasing the likelihood of spills.
environments. Other byproducts might include aromatic Changes in ocean currents and sea level rise can also
and aliphatic compounds that can bioaccumulate in influence the transport and fate of spilled oil, making
the food chain, leading to long-term chronic toxicity in prediction and cleanup efforts more challenging. 96
higher trophic levels. Photo-oxidation may also generate
oxygenated PAHs, which exhibit enhanced toxicity 5. Effects of hydrocarbon pollution
compared to their parent compounds. They may cause
DNA damage, oxidative stress, and endocrine disruption in Large quantities of hydrocarbons in the sea, whether
marine organisms, affecting their development, behavior, from heavy crude oil, light oil, or refined products,

Volume 22 Issue 6 (2025) 34 doi: 10.36922/AJWEP025290224