Enviro Unit 2

Properties of mercury

• Liquid and room temp

• Heavy metal

• Can form both organic and inorganic compounds

Elemental mercury

Can not break down any further, so is highly persistent, released by the burning of fossil fuels

Inorganic mercury

Forms when mercury bonds with other elements.

Organic mercury

Forms when mercury bonds with carbon, forms methylmercury. Can bioaccumulate, is neurotoxic

Sources of mercury

Natural - volcanic eruptions, black smokers, forest fires

Anthropogenic - fossil fuels, industrial processes.

Mercury affects on human health

Numbness/tingling, loss of coordination, reduction of visual abilities, nerve and brain impairment

Properties of Sulfur dioxide

• Colourless

• Strong odour

• Synergistic, can form sulfur trioxide that can then form acid rain

• Can attach to dust particles

Sources of SO2

Natural: Volcanic eruptions, bush fires, organic decay

Anthropogenic: Fossil fuel combustion, vehicle exhaust, industrial processes

Human impacts of SO2

Respiratory issues like lung damage, coughing, eye/nose/throat irritation

Environmental impacts of SO2

Acid rain formation, high acidity can damage ecosystems

Properties of nuclear waste

Highly persistent due to long half lives, can cause genetic damage

Point source

Pollution originating from just one source (e.g. a pipe)

Diffuse source

Pollution originating from multiple sources (e.g. cars on a highway)

Mobile emissions

Pollution originating from mobile sources like cars/transport.

Fugitive emissions

Pollution originating from various settings like buildings.

Persistence

Ability of pollutant to resist degradation in an environment over time.

Mobility

Ability of a pollutant to move through the environment.

Bioaccumulation

Process of pollutants accumulating in tissues of organisms faster than can be excreted/gotten rid of.

Transport pathways

Routes/mechanisms that pollutants are transported in the environment.

Sinks

Environmental reservoirs where pollutants accumulate.

Dosage

The amount of substance absorbed per unit of body weight. Measured in mg/kg/day.

Toxicity

The harm a substance can cause to an organism.

Acute toxicity

Effects after a single dose

Chronic toxicity

Effects over a prolonged or repeated exposure

LD50

The dose that will cause death of 50% of the population.

Waste

Material, subject or byproduct eliminated or discarded as no longer required/useful

Contamination

The presence of a substance where it does not naturally occur

Pollution

Contamination that results in adverse biological effects.