The Three-Body Problem. It reminded me of the fact that, despite studying environmental science for eight years, I haven't actually read this book. I've been aware of it of course. The book is inescapable if you want to understand the development of the environmental movement, but when I was in college the book had already reached the status of a work like Darwin's On The Origin of Species. Everybody knows it, many have an opinion on it, but very few people have actually read it. Time to change that, better late than never.
Carson's book is widely lauded as the book that launched the environmental movement (the cover of my edition boldly states so). That is probably too much credit. The environmental movement is very diverse and in areas like landscape protection and protection of species it goes back a lot further than the 1960s. What it does do is point out how little we actually know about the vast array of chemicals we are introducing into the environment. The book focuses on just a few, but even in doing that, it raises questions we still haven't answered satisfactory.
Copies of Silent Spring are, more than fifty years after it was first published, still widely available so I ordered the fifty year anniversary edition published by Mariner. It has an introduction by Linda Lear, who wrote an extensive biography of Carson, and has an afterword by the influential biologist Edward O. Wilson. There is something ironic about having Wilson write an afterword to a book that challenges the indiscriminate use of pesticides. Wilson, together with Robert H. MacArthur, is, among other things, known for the theory of insular biogeography. The theory he had developed was tested by fumigating small islands in the Florida Keys with methylbromide (which besides being toxic, had the added, but at the time unknown, benefit of being ozone depleting) to see how quickly they were repopulated. Carson of course, would probably not have argued against this experiment. One of the many misunderstandings about this book is that she advocated bans on pesticides, in particular DDT. Nowhere in the book does Carson mention this. What she does mention is the need for a deeper understanding of ecology.
One of the many accusations leveled against the book is that it is alarmist. In the first brief chapter of the book Carson certainly feeds that suspicion. It is a very eloquent description of a future in which the spring is indeed silent and empty of life. She then quickly proceeds the core of the matter however, and takes aim at the reader with a barrage of examples of the disastrous effects the indiscriminate use of pesticides have had. In the 1950s and early 1960s the use of these chemicals was enormous so she had plenty of material to draw from. The list of studies Carson used is included in the back of the book and takes up over fifty pages. The real merit of Carson's work is not so much in adding to our knowledge rather than collecting it and keeping the overview. All these studies combined paint a picture that had Carson thinking along similar lines as Paul Shepard (he would go on to make a name for himself in the Deep Ecology movement) whom she quotes in the second chapter.
“Why should we tolerate a diet of weak poisons, a home in insipid surroundings, a circle of acquaintances who are not quite our enemies, the noise of motors with just enough relief to prevent insanity? Who would want to live in a world which is just not quite fatal?”Who indeed? After posing this question, Carson goes into detail on how pesticides are ruining the environment, pointing out that many of them kill indiscriminately and that humanity is not excluded from the list of species these substances have an effect on. The book is full of references to things that would become very important in environmental research. Bioaccumulation, the toxicity of metabolites, effects on hormone levels and influences on fertility, issues of resistance in target populations and damage to species important to pollination all show up in the book. The book is full of examples where, even in the short term, the damage done by pesticides far outweigh the supposed benefits. Carson readily admits that knowledge to predict future damage is simply insufficient since companies producing these substances were only required to do relatively few standard toxicity tests.
Paul Shepard as quoted by Rachel Carson in Chapter 2 The Obligation to Endure.
None of these things are new to me so they didn't particularly shock me as I imagine people who read this book quickly after publication might have been. What I did find shocking was the easy acceptance of the (often massive) dosage the manufacturers claimed were safe and insistence on continuing with these practices in the face of massive die off in all manner of species after spraying. What is perhaps even more shocking is the complete disregard of human health displayed on some occasions. One scientist quoted in Silent Spring likened existing practices of pesticide use to 'walking in nature like an elephant in the china cabinet' which strikes me as very apt.
In her book Carson mostly looks at two groups of pesticides. The organophosporus compounds (e.g. dichlorvos, malathion and parathion) and the organochorides (e.g. DDT, dieldrin, aldrin, heptachlor, clordane, 2, 4-D). Carson doesn't mention it in her book but when you think about it, she discusses a very limited group of chemicals. These are but a few of the chemical compounds humanity have been adding to the environment and while their effect may have been very eye-catching, there are countless more of which we have very little idea what their effect may be. What is worse, we're not trying very hard to find out either.
While Carson's arguments to be much more judicious in the uses of pesticides is clear, well reasoned, and frankly, inescapable, not all the science in the book holds up well. The chapter on genetics is, by today's standards, weak. It is clear that Carson only had a superficial knowledge of the mechanisms involved and our knowledge in this branch of biology has expanded exponentially since the 1960s. Another part I found problematic was the chapter on the link with cancer. Carson appears convinced of the carcinogenicity of many of these chemicals. It has proven difficult to find these links. DDT for instance, is listed as, depending on who you ask, a probable or possible carcinogen. Some claim it is not carcinogenic at all. Given de discussion about this chemical you can be sure there is a lot of research available on the subject, but apparently not enough to be conclusive. From Carson's chapter on the subject it is quite clear that science on the development of tumors has advanced a great deal too. I get the impression she is being a bit too quick to draw conclusions there.
One of the things Carson says over and over again in the book is that our reliance on chemicals is unnecessary and that with a more balanced and multipronged approach to containing pest species, the use of pesticides could be greatly reduced. Throughout the text she lists quite a few possibilities, many of which have been applied with varying degrees of success in the years since the publication of Silent Spring. Carson appears especially interested in biological pest control, which can yield great results but also carries risks. In some cases organisms imported to combat pests have become pests themselves. Carson may have underestimated this risk a bit.
Silent Spring is clearly written for a larger audience than just scientists. It contains a great deal of scientific detail but the material is dealt with in a way that doesn't require a great deal of prior knowledge on the subject. The text and chapters are clearly structured and Carson seems to be very fond of rhetorical questions. Carson's tone is nothing short of challenging in most chapters. She is clearly angry by the way in which both the authorities and the manufacturers have ignored the obvious problem and insisted on continuing programs that were wasting money and doing a great deal of damage. Carson expected a strong response and that is exactly what she got.
It is a great tragedy that she did not live to see the full impact the publication of Silent Spring had. By the time it was published, she was already seriously ill and undergoing radiation treatment for cancer. She died April 14th, 1964. Before that, she did manage a few public appearances, including a testimony before a Senate subcommittee. The impact of her book eventually lad to the establishment of the Environmental Protection Agency and a number of restrictions on the use of a number of chemicals. It continues to influence a number of ecological schools of thought until this day.
What Carson did live to see, at least in part, is the mudslinging unleashed by the publication of her book. Carson and her publishers were threatened with legal action, she was portrayed as a hysterical woman and alarmist, and a poor scientist trying to drag humanity back to the stone age. Some even went so far as to call her a communist. Until this day, some groups are accusing her of having caused the death of millions by getting DDT banned for control of the malaria mosquito. This bit of misinformation is particularly hurtful. Carson never called for a ban on DDT, the ban that is usually being referred to is one on most agricultural uses in the US (not the nation most troubled by malaria when that bill was passed in the 1970s) and did include an exemption for health emergencies. It is a discussion that will probably keep going. At the centennial of her birth a bill to honour her was blocked in the US Senate because of the DDT controversy. The strategies employed against Carson reminded me a bit of what Paolo Bacigalupi describes in his novel The Doubt Factory.
After more than half a century it is always easy to poke holes into the scientific knowledge of the day. Not everything that Carson claims in her book is correct and not every solution she proposes works. That being said, the book put a subject on the agenda that very much needed to be discussed. After reading it, I feel the eternal link between DDT and Silent Spring is an oversimplification of what Carson tried to achieve. Her message was much more complex and subtle, not just raging against a particular chemical as some people want us to believe. The mere fact that this discussion is still ongoing, makes it clear that Silent Spring hasn't lost any of its relevance. Just think about the recent discussion on bee mortality and that of other pollinating insects. The knee jerk response to blame insecticides appears to be only part of the answer there. What Carson called for was an increase in knowledge, a deeper understanding of what happens when we introduce a chemical into the environment, so that we can weigh the pros and cons carefully before acting in what seems like the easiest and most immediately profitable way only to find out about the long term consequences when the damage is done. Silent Spring is a book everybody with an interest in environmental matters should read, and, after you are done, think about carefully instead of jumping on one of the bandwagons of people who use the fame of this work for their own purposes.
Title: Silent Spring
Author: Rachel Carson
Publisher: Mariner Books
First published: 1962