Regulating and Reducing Pollution

What is the Ocean Health Index? Using a new comprehensive index designed to assess the benefits to people of healthy oceans, a group of scientists led by Ben Halpern have evaluated the ecological, social, economic, and political conditions for every coastal country in the...

Emerging Concerns

What other types of contaminants are we beginning to learn about? Contaminants of emerging concern (CECs) have been defined as any man-made or naturally occurring chemical or microorganism that is not generally monitored in the environment but has the potential to enter the environment...

Metals

What are the major sources of metal pollutants? Metals are naturally occurring elements in the earth’s crust that can become contaminants when industrial activity concentrates them at higher than normal levels. Since they are elements, they cannot break down into anything else. Metals released...

Oil and Related Chemicals

What are the components of oil? Oil is a complex combination of various hydrocarbons (carbon-based compounds with hydrogen atoms attached). Petroleum hydrocarbons are the primary constituents in oil, gasoline, diesel, and a variety of solvents. Oil and related substances don’t generally mix with water...

Introduction to the Marine Environment and Pollution

What is the marine environment? As used in this book, the marine environment covers not only the ocean, but estuaries (e.g., bays), which are coastal areas where the seawater is diluted with freshwater coming from rivers and streams, or sometimes groundwater. Much of the...

Climate Change and Ocean Acidification

What causes global warming or climate change? The burning of fossil fuels emits carbon dioxide into the atmosphere, which results in the greenhouse effect—less heat can be re-radiated away from the earth, thus raising the temperature of the atmosphere and ocean. In the past...

Bioaccumulation and Biomagnification

What is bioaccumulation and what is biomagnification? Organisms take pollutants up from the environment through their skin, gills, or digestive system. The term bioaccumulation is generally used to describe uptake, but there are specific terms that refer to specific ways they do so. Bioaccumulation...

Pesticides and Industrial Organic Chemicals

What are the sources of pesticides to the marine environment? Pesticides from agriculture, lawns, golf courses, and gardens wash into streams and rivers and ultimately down into estuaries. These chemicals are designed to kill agricultural pests (generally insects) on land. After being sprayed on...

Marine Debris

Why is marine debris so abundant? Marine debris is any solid manufactured item that enters the marine environment, including cigarette butts, fishing line, diapers, bottles and cans, syringes, and tires. It is a pervasive pollution problem that has been made worse by the increasing...

Nutrients

Why are nutrients considered pollutants, since they are required for life? Input of excess nutrients such as nitrogen (N) and phosphorus (P) causes major problems in the aquatic environment. While phosphorus tends to be the main cause in freshwater, nitrogen is the major source...