Unit 2: Chemicals & Chemical Exposure in the Environment

Question 1

Examples of toxic anthropogenic chemicals

Answer 1

1) organochlorine pesticides - DDT, dioxins, phthalate esters
2) inorganic metals - cadmium (Cd), Arsenic (As)

Question 2

Major routes of entry of chemicals into human body

Answer 2

1) oral ingestion
2) absorption through the skin

Question 3

Name some natural sources of organic compounds

Answer 3

fossil fuels - natural gas, petroleum and coal

Question 4

Major classes of pollutants (Synthetic & natural)

Answer 4

• Ions (Zn, Pb, Hg)
• Anions (nitrates, phosphates)
• Organic pollutants (hydrocarbons, PCBs, organochlorine pesticides, organophosphates, pharmaceuticals & gaseous pollutants)

Question 5

What are exposure pathways & exposure routes - examples of each

Answer 5

The pathways and avenues by which toxic chemicals find their way into physiological systems of humans and other living organisms.
Exposure pathways = air, water, and soil
Exposure routes = ingestion/mouth, nose/breathing, skin/contact