SCIE 1P50 Lecture Notes - Stockholm Convention On Persistent Organic Pollutants, Dielectric, Bioavailability
This preview shows half of the first page. to view the full 2 pages of the document.
Class #7! Science & Society! September. 28, 2011
HAHs (Halogenated Aromatic Hydrocarbons)
- Some of the original uses were as chemical weapons. CL2 has was used in the World
War 1 as well as dichlorodiethyl sulphide
- Later in the later 1920s and 1930s, industry began to manufacture polychlorinated
biphenyls (PCBs), chloroﬂuorocarbons (CFCs or Freons), and p, p-
dichlorodiphenyltrichloroethane (p, p-DDT, generally called DDT). These compounds
made a major impact on society, especially DDT.
- Polychlorinated biphenyls (PCBs) are a class of 209 organic compounds. Each one is
often called a congener.
- Only ~140 congeners of the 209 are found in the environment.
- Used as dielectric & heat transfer ﬂuids in transformers, in lubricating and other oils,
pesticides, paints, sealants, and plastics.
- Very stable compounds
PBDEs & HBCDs
- Polybrominated diphenyl ethers
- Flame retardants (PBDEs/HBCDs) are now found in humans and other species
everywhere in the world. Harm children’s reproductive and nervous systems.
- Chemicals used in non-stick plastic coatings are inﬁnitely persistent in the environment
and found in your blood.
- DDT banned in Canada in 1970(1985) and 1972 in U.S.
Long Range Transport of Air Pollutants LRTAP
- Evaporation > deposition
- Mid Latitudes - seasonal cycling of deposition and evaporation
- Long-range atmospheric transport
- Long-range oceanic transport
- Deposition > evaporation
- Agreement to eliminate the production of certain POPs
- Adopted in 2001
- >152 countries signed the agreement to date
- Stop production of PCBs immediately.
- Stop using PCB laden equipment by 2025.
You're Reading a Preview
Unlock to view full version