Silent spring and beyond

Rachel Carson 1962

public concern of pesticides and pollution of the environment. facilitated the ban of the pesticide DDT in 1972 in USA

chemical pollution in the natural environment results in a spring without songbirds. build up of these chemicals through the trophic levels from crops to animals - predators positive feedback bad for envt

• born 1907 • masters degree in zoology • author of other books - ‘the sea around us’,’edge of the sea’,’under the sea wind’ • target audience were housewives

same argument as Carson flopped at publication Carsons was more of a personalised take so people can see themselves

lots of concern about radiation at the time due to nuclear war threats. Carsons talk about silent killer was relevant. other books at the time focuses on a moral call to arms 60/70s was rapid time of change evidence based writing

dichlorvos diphenyl trichloroethane • non-selective so kills everything in its path • first developed in 1874 • insecticidal properties not discovered till 1939 • used in WW2 to control malaria and typhus • discovered by Paul Hermann muller • after WW2 increased for agricultural use • sprayed out of planes onto forests to kill insects. sprayed on planes to stop disease. used in domestic settings • is now concidered a probable carcinogen

first noted in 1950s • sprayed to kill beetles carrying dutch elm disease • study by barker 1958 showed accumulation of DDT in lethal levels to robins in earthworms- showed how it was due to food not water

decline in peregrine falcons in UK - secondary victims of agricultural toxic chemicals poisons accumulate leading to a lethal dose eggshell thinning on eggs as an effect - issue for other birds too. wouldn’t hatch

showed value of birds ‘poisoning of natural landscae’ public eye

ban of DDT in 1972 by EPA silent spring rallied for social movements rise of ecofeminism Carson testified before Kennedy

result of Carsons campaigning 1967 non profit law suit against gvt

100 countries signed UN treaty - eliminate use of 12 persistent, toxic compounds including DDT - use of pesticides only for controlling malaria

sceptics say millions suffered as a result of the ban Carson blamed for rise in malaria

DDT is low cost, easy application and efficient graphs show a trend in DDT and malaria, but must be careful as need to consider other factors variables -DDT is now one of 12 pesticides recommended by WHO for indoor spray programmes

insecticide against malaria don’t last long in running water as broken down or diluted more selective in targeting species

evidence that humans transfer a significant proportion od bodies DDT and its metabolites into infants - effects unknown

1953 - USAs worst polio epidemic correlation doesn’t always mean causation even if there’s a relationship, doesn’t mean its functional lots of quack theories

• must think critically • PCBs in all plastics • impacts unknown • affecting seabird population