Ch 3: Laboratory curiosities and the world unknown By: Peiyu Guo, Monica Callaghan, Thomas Cleary

1 billion adults in this world are overweight ⅔ of American adults are obese trippled the rates of obesity among adolescents since 1960s. The risk of obesity:possibly cause Cardiovascular disease !! Diabetes!! stroke!! EVEN Cancer!!

The surface of a cell

Curiosity and Unknown In 1930s, chemical engineers shifted the use of natural stuff as feedstock to petroleum products. And they successfully created flexible, moldable and durable polymers which are large molecules typically made up of many repeating smaller units. Polymers are physically large so the have often assumed to be unlikely to enter or interact biologically with living cells. However, a presentative of the Dupont company said “60 % of what we made today are unknown, at least were only laboratory curiosities, as recently as 1930.”

in 1930’s newly synthesized materials “absolute resistance to water and had high insulation properties” made from chlorinated rubber and hydrocarbon products (used in paints, coatings for metal, or synthetic fibers for cloth) could be easily shaped or molded now known as polyvinyl chloride or PVC now accounts for 90% of all plastics in use controversial because of environmental and health impacts during manufacture, use, and disposal has phthalates (known now as endocrine disrupters) and lead (a neurotoxin)

Concerns with new developments 1960’s and 70’s concerns began to circulate about health impacts from the polyvinyl monomer which PVC is made from (now a recognized human carcinogen) also exposure to synthetics, heptachlor, dieldrin, and aldrin attributing to serious/ fatal illnesses (acute nervous system effects, resulting in comas or blindness)

Influence of oil Many companies involved in chemical engineering in the 1930’s also in the petroleum business petroleum was cheap (didn’t exceed more than $40/ barrel until 2001) 2008, $4-5 gallon of gas, acceleration of prices in more than 25 years - affected everything from produce to plastics

The Effect of Synthetic Chemicals on humans and Animals The public became more aware of the ways manufactured materials were affecting their lives with the publication of Rachel Carson’s Silent Spring in 1962 Carson noted that these materials had been emerging since the mid-1940s One chemical that came under particular scrutiny was the pesticide DDT which caused bird’s eggs to become too soft to survive

The Reaction Because of the public outcry of the 1960s and 1970s certain synthetics began to be taken out of use Pesticides such as DDT, dieldrin, lindane, mirex, and toxaphene became less common as well as the coolant/insulator chemicals known as PCBs A dozen synthetic chemicals were banned in the 2001 Stockholm Convention on Persistent Organic Pollutants and nine more were banned in 2009 Despite this the chemicals used decades ago persist in the environment to this very day

Where are we now? Current trends such as climate change, globalization, and the rise of consumer electronics are making it harder to deal with the effects of synthetic chemicals in the environment When Rachel Carson wrote Silent Spring in 1962 there were about 500 new chemicals produced per year, now there about 2000 of the chemicals used commercially in the U.S. and Canada 400 are considered potentially dangerous, yet only 4% of these are consistently studied and 75% have not been studied at all

Questions What are some of the harmful effects of these new chemicals on the human body? What was the role that oil played in developing these new chemicals? What are some developments in society since harmful effects of these chemicals have been discovered?