A major effect of oil pollution in coastal water is

Analysis

The question asks for the primary environmental impact of oil spills (oil pollution) on coastal ecosystems. We need to evaluate how crude oil or petroleum products interact with marine life and water quality.

Concept Explanation

When oil is spilled into coastal waters, it creates several hazardous conditions:

1. Physical Coating: Oil coats the feathers of birds and the gills of fish, preventing them from breathing, flying, or regulating their body temperature.
2. Toxicity: Crude oil contains toxic hydrocarbons that can poison marine organisms upon ingestion or skin contact.
3. Oxygen Deprivation: A layer of oil on the surface of the water prevents the diffusion of atmospheric oxygen into the water, leading to hypoxia (low oxygen levels) for organisms living below the surface.
4. Habitat Destruction: It smothers coral reefs, mangroves, and seagrass beds, which serve as breeding grounds for many aquatic species.

Step-by-Step Solution

• Option A (Destruction of aquatic life): As explained above, oil pollution is lethal to fish, crustaceans, birds, and plants. It disrupts the entire food chain, leading to massive die-offs. This is the most significant and direct effect.
• Option B (Nitrification): Nitrification is the biological oxidation of ammonia to nitrite and nitrate. Oil pollution does not cause this; in fact, it often inhibits the bacteria responsible for natural nutrient cycling.
• Option C (Detoxification): Oil pollution is the opposite of detoxification; it introduces toxic substances into the environment.
• Option D (Disinfection): Disinfection refers to the removal of pathogens (like bacteria or viruses). Oil pollution does not clean the water; it contaminates it.

Conclusion

Based on the environmental impact, oil pollution leads to the death and destruction of the ecosystem. Therefore, the destruction of aquatic life is the major effect.

Exam Tip

When answering environmental chemistry questions in JAMB, always look for the "negative impact" option. Oil pollution is a classic example of environmental degradation, so look for keywords like "destruction," "toxicity," or "suffocation" rather than "purification" or "nutrient enrichment."