October 12, 1999: 6 billion! Now doubling every 61 years December, 2012: 7 billion!

October 12, 1999: 6 billion!

Now doubling every 61 years

December, 2012: 7 billion!

Pesticides and theGREEN REVOLUTION

can we feed the planet?

Since 1950 food grew faster than population:

population growth: 1.7% per year

food growth: 3% per year

land growth: 0% per year

10% of Earth’s surface produces food37% of Earth’s land produces food

Total surface area of earth 5.1 1014 m2

Land 25% 1.3 1014 m2 13 Gha 10% 4.8 Gha

(1 hm = 102 m; 1 ha = 1 hm2 = 104 m2)

pastures: 3.3 Ghacropland: 1.5 Gha

A rab lelan d11 %

(1 .4 4 b illio nhec ta re s)

O the r land33 %

(4 .3 5 b illio nhec ta re s)

a

F orest and w ood land30 %

(3 .8 9 b illio nhec ta re s)

P e rm an en tm eado w s & p astu re s

26 %(3 .3 6 b illio n

hec ta re s)

17 % o f a rab le landis irriga ted(2 40 m illion h ec tare s)

The Earth's LandTotal Area: 13 Billion Hectares

Other land" includes barren and developed land.

Source: Food and Agriculture Organizationfrom Committee for the National Institute for the Environment

http://www.cnie.org/pop/conserving/landuse2.htm

[1] development of high yield strains of grains

[2] increased use of inorganic fertilizers[3] irrigation[4] synthetic pesticide use

The green revolution:

increase productioneliminate competition

3 times more foodbeing produced

then in 1950

Are thereany

environmental impacts?

Glyphosate (G) is the largest selling herbicide worldwide; the most common formulations (Roundup, R) contain polyoxyethyleneamine as main surfactant.

Recent findings indicate that G exposure may cause DNA damage and cancer in humans.Arch Toxicol. 2012 Feb 14. Epub 2012 Feb 14. PMID: 22331240

Glyphosate kills EPSPPlant cannot make Aromatic aminoacids

Dow Chemical (the main manufacturer of DDT) and the Velsicol Chemical Companywere the first to respond to the publication of Silent Spring.

They threatened legal action against the publishers as well as the magazinespublishing excerpts, and then they began publishing their own brochures, documentaries, books and articles promoting the safety of pesticides while attacking Carson and her book.

Staunch critics claimed that if we followed the advice of this “Doomsayer” that we’d return to the Dark Ages and insects would inherit the earth.

Some attacked Carson’s scientific credentials (she was only a marine biologist), while others labeled her “a fanatic defender of the cult of the balance of nature.” Finally there were those who called her a Communist.

Metabolic breakdown product, DDE:

Properties of DDT and other organic compounds

1. very stable

2. low stability in water

3. high stability in hydrocarbonsolvents

4. high toxicity to tissues

5. relatively low toxicity to humans

The idea ofBIOMAGNIFICATION

Fish are living separatory funnels

They ingest water containing DDT

The DDT dissolves in the fatty tissues of their bodies

Biomagnificationin Long Island Sound

[DDT] in sea water 0.000003 ppm

[DDT] in plankton 0.04 ppm

[DDT] in minnows 0.5 ppm

[DDT] in needle fish 2 ppm

[DDT] in cormorants 25 ppm

Polychlorine biphenols = PCBs

© 2012 W. H. Freeman & Co.

© 2012 W. H. Freeman & Co.

© 2012 W. H. Freeman & Co.

LD50

A measure of toxicity

1. Feed DDT to rats (spike their food)

2. Continue upping their dose until half of the die

3. Measure concentration of DDT in the rats

4. LD50 = (mass of DDT in rats) # Kg of rat

© 2012 W. H. Freeman & Co.

© 2012 W. H. Freeman & Co.

© 2012 W. H. Freeman & Co.

Some of the top global environmental disasters:

• Photosynthesis• Meteorite impact• Global warming

Some of the top local environmental disasters:

• Bophal• Love canal• Soveso• Three mile Island• Chernobil• Fukushima• Exon Valdez• Horizon platform