Chapter #10 Pollutants

What is the difference between a contaminant and a pollutant?

Contamination is a substance being where it should not be or at high amounts; pollution is contamination resulting in adverse biological effects.

What are the two classifications of pollutants?

Toxicants (natural/artificial toxic chemicals) and toxins (produced from living cells or organisms).

What is bioaccumulation?

The buildup of absorbed chemicals in just one organism.

What is biomagnification?

The buildup of chemicals in all organisms in the food chain.

What are the main sources of pollutants?

Agriculture, Urban/Industry, Shipping, Landfills, and Accidents.

Where do pollutants drain to?

Air (aerosols), Water (dissolved particles), and Suspended particles.

What determines how pollutants act in the water column?

Their persistence and potential for bioaccumulation.

What is the main determinant of how much pollutant will be in the water column?

Solubility; higher soluble pollutants are more widespread.

How do pollutants spread in the water column?

Particulate form as suspended particles will be found in sediments; dissolved pollutants will bioaccumulate or biomagnify.

What are the four main insecticides?

DDT, Dieldrin, Chlorpyrifos, and Endosulfan.

What is DDT and its impact?

DDT causes photosynthetic depression and has significant ecological impacts.

What are herbicides and their effects?

Herbicides are dangerous due to quick uptake by plants and can cause coral bleaching.

What are organochlorines?

Pesticides known for their persistence, bioaccumulation, and negative effects on reproductive capacity.

What are common organochlorines?

Hexachlorobenzene, Hexachlorocyclohexane, and Polychlorinated biphenyls (PCBs).

What are today's PCB concentrations in the upper ocean?

Estimated to have declined by over 90% since 1970.

What are trace metals as a toxicant?

Metals that are often buried in sediments, increasing risk for sessile organisms.

What are hydrocarbons as a toxicant?

Crude oil and petroleum combustion products that cause major environmental problems.

What are the important components of an oil spill?

Oil aerosols, surface spills, oil flocculent, microdroplets, and buoyant plumes.

What processes affect oil spills?

Aerosolization, spreading/emulsification, absorption, sinking/sedimentation, and hydrate formation.

What are UV filters?

Substances used to absorb or block UV radiation, commonly found in personal care products.

What are marine plastics?

Synthetic polymers that impact the ocean by altering the food web.

Why is plastic debris dangerous?

It can leach chemicals into water, absorb toxic contaminants, and does not biodegrade.

What are PFAS and why are they called 'forever chemicals'?

Used in water-repellent coatings and personal care products, they are widespread and persistent.