I would add to the answers above that because Carson's work eventually led to an almost complete global banof DDT's use, we are still effected by it today. While Silent Spring obviously brought attention to environmental issues, it also demonstrates how powerful environmental agencies can become. For example, because DDT is banned, the U.S. which sends a tremendous amount of aid to African each year to try to prevent malaria cannot encourage or provide funding for the use of DDT sprays which are far more effective at preventing malaria than the flimsy nets that we offer impoverished Africans instead. Since Carson's book was first published, several studies have shown that far more people die of malaria than from DDT-related issues (in fact, it has been difficult to prove that any die from DDT).
In the midst of today's plethora of environmental books and articles, Carson's Spring is still undeniably pivotal; unfortunately, it seems that many authors get away with presenting junk science which can actually end up harming more humans than their habitats.