PART X — ENVIRONMENTAL CONTAMINANTS 



3. PESTS AND PESTICIDES 



Environmental Pollution and Pesticides 



The history of man is a history of 

 his modifying his environment to 

 suit his own needs and desires for 

 food, shelter, and the pleasures of 

 his own leisure. Primitive man lived 

 as an integral part of the living and 

 nonliving environment, but as his 

 proficiency to further his own ends 

 has advanced, he has progressively 

 taken on a more dominant, displacive 

 role. Because of his success and his 

 awesome technology for modifying 

 the world in achieving that success, 

 man now faces the dilemma that if he 

 proceeds as he has been he will de- 

 stroy or greatly lessen the earth's 

 capacity to sustain life, himself in- 

 cluded. 



Shortcomings of Present 

 Technology 



Among his technologies, some of 

 which embody greater attacks on the 

 biosphere, man has developed an 

 "advanced" technology of pest con- 

 trol. This technology can only buy 

 time while we find a solution to the 

 main problem of human population 

 growth and establish a redirection 

 of all our technologies along more 

 compatible ecological lines. 



Pest-control technology, through 

 use of modern synthetic chemical 

 pesticides, achieved a high degree of 

 perfection in terms of control of in- 

 sect pests for a time. It was, however, 

 developed single-mindedly with no 

 real regard for ecological conse- 

 quences. It was based on the stag- 

 geringly false cliche that "the only 

 good bug is a dead bug," and on the 

 incomprehensible premise that each 

 pest problem is a separate one — with 

 no entangling feedback loops disturb- 

 ing to crop-protection objectives. 

 Thus, we have developed deadly, 

 broad-spectrum, persistent pesticides 

 and used them too indiscriminately 



and in ignorance of, and disregard 

 for, ecological consequences of vital 

 concern, often creating pest situa- 

 tions worse than the original ones, 

 to say nothing of ancillary problems 

 of much importance. 



Among the adverse consequences 

 of a single-objective pesticide tech- 

 nology are: 



1 . Resistance has developed in 

 many target species. (See Fig- 

 ure X-ll) The more rapid the 

 resurgence, the more rapidly is 

 resistance developed; and re- 



sistance to alternate materials 

 then used often develops even 

 faster. 



Most materials are nonselec- 

 tive, directly affecting the nat- 

 ural enemies of the target pest, 

 often more so than the pest. 

 Rapid resurgence of the pest 

 species then occurs. 



Destruction of key natural en- 

 emies can be indirect, through 

 too severe destruction of the 

 target pest itself (the enemies 

 starve out) and through de- 



Figure X-11 —RESISTANCE OF INSECTS AND MITES TO PESTICIDES 



1910 



1920 



1930 



1940 1950 



YEARS 



1960 



1970 



1980 



The graph shows that the number of resistant species has been increasing rapidly 

 since the early 1950's and now stands at about 240. The changes in pest species 

 that allow them to survive at higher and higher concentrations of insecticides are 

 genetic and result from natural selection. Unfortunately, the graph tells the story 

 only of known pests. Large numbers of insect species that have not been examined 

 are subject to the same selection for resistance. When and if these insects erupt 

 as agricultural pests, they will already possess a significant resistance to pesticides. 



350 



