Unit 8 Notes: Aquatic & Terrestrial Pollution

Point Sources vs Nonpoint Sources
- Point Source: Identifiable, confined source of pollution. Examples include:
- Smokestack emissions (CO2, NOx, SO2, PM)
- Waste discharge pipes (e.g., wastewater)
- Oil spills (e.g., BP Oil Spill - hydrocarbons, benzene)
- Nonpoint Source: Diffuse sources that are difficult to identify. Examples include:
- Urban runoff (motor oil, nitrate fertilizers)
- Pesticides from agricultural spraying
- Animal waste runoff

Organism's Range of Tolerance:
- Organisms can tolerate various pollutants. Outside optimal ranges can lead to:
- Physiological stress
- Limited growth/reproduction
- Potential death
Impact Examples:
- Coral reefs affected by rising temperatures and runoff
- Oil spills lead to mortality for marine organisms

Endocrine Disruptors: Chemicals that interfere with the hormonal systems of organisms, affecting their reproduction.
- Examples include atrazine (herbicide) and DDT (insecticide).
- They can cause birth defects and developmental disorders.

Wetlands: Areas where water covers soil, providing ecological services like water purification and flood protection.
- Threats include commercial development and agricultural pollutants.
Mangroves: Important for coastal protection and biodiversity, but facing threats from climate change and urbanization.

Eutrophication: Nutrient enrichment in water bodies, primarily from runoff.
- Leads to algal blooms, decreased sunlight, and hypoxia (low oxygen), causing aquatic die-offs.

Thermal Pollution: Heat released into water can harm aquatic organisms.
- Warm water holds less oxygen, increasing the risk of suffocation for aquatic life.

POPs: Long-lasting synthetic chemical compounds that do not easily break down and can accumulate in living organisms.
- Example substances include DDT and PCBs, known to disrupt endocrine functions.

Bioaccumulation: The accumulation of substances in an organism.
Biomagnification: Increasing concentrations of substances in organisms at higher trophic levels.
- Top predators, such as sharks, have the highest contaminant levels (e.g., mercury).

Types of Solid Waste:
- Municipal Solid Waste (MSW) includes everyday trash; E-Waste refers to discarded electronic devices.
Landfill Issues: Can contaminate groundwater and emit harmful gases.

The Three Rs:
- Reduce: The most effective way to minimize waste generation.
- Reuse: Extends the life of products without additional energy inputs.
- Recycle: Although energy-intensive, recycling conserves raw materials and reduces landfill space.

Sewage Treatment Process:
1. Primary Treatment: Physical removal of large debris.
2. Secondary Treatment: Biological breakdown of organic matter by bacteria.
3. Tertiary Treatment: Further ecological or chemical treatment to remove pollutants before discharge.

LD50: The dose of a substance that kills 50% of a population.
Dose-Response Curves: Graphical representation of the relationship between toxin concentration and effect on organisms.

Health Issues Linked to Pollution:
- Difficult to separate specific pollutants from health problems due to multiple exposure routes.
- Examples: Dysentery, Mesothelioma (asbestos), Respiratory conditions (tropospheric ozone).

Disease Transmission:
- Tuberculosis, Malaria, Zika virus transmitted via vectors (e.g., mosquitoes).
- Cholera caused by contaminated water.
Environmental Links: Poverty and lack of sanitation contribute to the spread of infectious diseases.