What environmental concern did Rachel Carson address in her book Silent Spring?

Rachel Carson's book "Silent Spring" primarily addressed the environmental concern of pesticide pollution, particularly the widespread use of chemical pesticides like DDT and their detrimental effects on the ecosystem. In her work, Carson highlighted how these chemicals not only killed pests but also had severe repercussions for wildlife, particularly birds, leading to declines in their populations. The title "Silent Spring" itself alludes to a future where the sounds of birds and other wildlife are absent due to the harmful impacts of pesticide application. Carson’s research and advocacy raised public awareness about the interconnectedness of all living organisms and the environment, playing a crucial role in the modern environmental movement and leading to regulatory changes concerning pesticide use.

The other concerns mentioned, such as deforestation, air quality, and noise pollution, are significant environmental issues, but they are not the primary focus of Carson's work in "Silent Spring." Her detailed focus on the specific impacts of pesticide use helps to understand the urgency of addressing pesticide pollution as a major environmental threat.