I think Carson is making a stronger argument about what is wrong with human interaction within the state of nature.  Her primary assertion is that like all organisms, there is a delicate ecosystem within which humans are immersed.  Human beings have to be mindful of their actions within this balance.  The use of pesticides and other chemicals might eliminate one part deemed not desirable, but this carries with it large ecological issues that impact more than simply ourselves.  The inherent barrier Carson sees is that individuals do not see themselves as part of this balance and, in failing to do so, are causing irreparable damage to their state of being in the world and those who happen to inhabit it.

Rachel Carson's Silent Spring was published as an environmental warning against the use of DDT and other pesticides, which she claimed was harmful to bird and animal populations, and through the food chain and water supply, harmful to humans as well.

She argued that by the interruption and extinction of species through the overuse of pesticides did both visible and invisible damage to the environment.  That it upset the state of nature by interfering with natural selection and evolution, and disrupting environmental processes and relationships that humans did not even understand. 

Her book is considered the spark that started the modern day environmental movement.