Chapter 18, Problem 1TC

To determine

The reason why refined oil is more dangerous than crude oil to the marine environment, the one among them that is spilled more often, and the effect of oil on the marine environment if it enters into it.

Answer to Problem 1TC

The refining process causes the concentration of the smaller biologically dynamic components of crude oil and also adds certain substances into the oil, as a result of which the refine oil becomes dangerous than the crude oil. The refined oil spill is more frequent than the crude oil spill. The insoluble constituents of the crude oil might form a sticky layer on the surface as a result of which the available amount of sunlight for photosynthesis declines, the feeding structures of organisms get clogged, and the diffusion of gases get hindered. However, since crude oil is biodegradable, its spill is not regarded as a highly fatal one.

Explanation of Solution

When the crude oil is refined, the heavier constituents of crude oil get removed and broken down in the process, as a result of which the remaining lighter, more biologically dynamic components get concentrated. In the refining process, certain components would be added to the oil because of which the resultant product becomes even more lethal.

Spills of refined oil, particularly adjacent to the coast where marine life grows in abundance, could be more disturbing for extended time periods than spills of crude oil. Spills of crude oil are usually greater in volume and occurs more often than spills of refined oil.

Much of the constituents of crude oil would not get dissolved in water easily; nevertheless, those which get dissolved could harm the subtle infantile forms of marine organisms, even in small concentrations. The leftover insoluble constituents develop into sticky coatings on the surface, which block the feeding structure of adult organisms, inhibit free diffusion of gases, and reduce the sunlight accessible for photosynthesis. Despite that, crude oil does not prove to be highly toxic, as it is biodegradable.

Even if crude oil spills appear dreadful and they create pronounced media attention, much of the marine life forms in a region recuperate from the impacts of a moderate spill in a time period of around five years. For instance, during the 1991 Gulf War, 126 million gallons of light crude oil were released into the Persian Gulf, and it degenerated comparatively rapidly and would have possibly caused slight long-term biological damage.