ddt is an insecticide that was used extensively quizlet

Due to the initiation of numerous court proceedings regarding the use of DDT, on October 21, 1972, the Federal Environmental Pesticides Control Act was enacted. also known as dichloro-diphenyl-trichloroethane, used to control insect vectors of disease, DDT in mothers linked to developmental delays in children, UC Berkeley study finds (press release), DDT still poisons people and wildlife in Michigan 40 years after being banned, DDT compounds found at deadly levels in Michigan birds and eggs, Study shows DDT to be toxic to nervous systems of babies, Monsantos DDT pesticide could raise breast cancer risk by 370%, Glucophage uses, health risks, and side effects at NaturalPedia.com, Norvasc uses, health risks, and side effects at NaturalPedia.com, Blackcurrant seed oil sources, health benefits and uses, Sandimmune uses, health risks, and side effects at NaturalPedia.com. Still, DDT remains in use in some countries. Q3.1. After decades of use, evidence of the pesticide's declining benefits and suspected environmental and toxicological effects were becoming causes for concern. There may be evolution of shell thickness, but not through natural selection and not necessarily toward thicker shells. What pattern best describes the relationship between frequency of HbS and malaria prevalence (as indicated on the map)? DDT has humble origins for a chemical that would eventually reach much of the world. If the cystic fibrosis allele protects against tuberculosis the same way the sickle-cell allele protects against malaria, what should happen to the frequency of the cystic fibrosis allele in the community over time, and why? Mutations toward thinner shells and mutations toward thicker shells are equally likely. Parents will pass on the HbS allele to their children more frequently in regions where malaria is common. Barry-Caban, Christobal S. "DDT and Silent Spring: Fifty Years After." 1,3 This happened because some bed bugs have a mutation that allows them to survive being sprayed with DDT. On March 14, 1975, the Administrator denied the State of Louisiana a request for emergency use of 2.25 million pounds of DDT on 450,000 acres of cotton to control the tobacco budworm in 1975. Both chemicals can be in breast milk, resulting in exposure to nursing infants. A person who is heterozygous for the cystic fibrosis allele moves to a small, isolated community where no one previously carried the allele. Why are the observed and expected frequencies of heterozygotes more similar to each other in the slightly wet region than they are in very wet region? Evaluate her hypothesis based on the results shown in both graphs above. be applied much in the same way as chemical insecticides (dusts, sprays, baits, etc.) In 1957, as a matter of policy, the Forest Service, U.S. Department of Agriculture (USDA), prohibited the spraying of DDT in specified protective strips around aquatic areas on lands under its jurisdiction. Also known as dichloro-diphenyl-trichloroethane, it is one of the most effective yet . It was initially used with great effect to combat malaria, typhus, and the other insect-borne human diseases among both military and civilian populations. What is your observed HbA frequency at generation 100? Most villagers have neither disease because they have the HbA/HbS genotype. Environmental Protection Agency. As part of the testing, a 4-mile area was blanketed with the DDT fog. can travel long distances in the upper atmosphere. After 100 generations in this village have passed, which of the following statements is true? DDT, also known as dichloro-diphenyl-trichloroethane,belongs to a class of pesticides called organochlorides. Julia Brody, executive director and senior scientist at theSilent Spring Institute, echoed Cohns sentiments. Q6.9. Nevertheless, DDT remains an effective insecticide against bed bugs and is sometimes used when other methods . People who are heterozygous for the sickle-cell allele: Are not susceptible to either sickle-cell anemia or malaria. These conditions are related to cardiometabolic problems such as insulin resistance, impaired glucose tolerance, and high blood pressure, and increased risk for breast cancer and some other cancers. Q5.10. odor . ), Q3.16. It still sees limited were found to be lasting . Shortly thereafter, particularly during World War II, the U.S. began producing large quantities of DDT for control of vector-borne diseases such as typhus and malaria abroad. In the above example, which genotype is represented by q2? Shell thickness did change in some of the trials, but the direction and magnitude of change is not consistent. In Lives of Weeds, agronomist John Cardina explodes myths about weeds and humanity, It's happening under the cover of strict coronavirus lockdown measures, Jury finds that because of dicamba, a peach farmer is going out of business, Numerous studies show that the pesticide is harmful to human health, Mild winters and energy-intensive snowmaking are in a positive feedback loop, False ideas about whats natural have driven bigotry for too long, Idaho, Montana, and Wyoming seek to expand hunting to keep populations to bare minimum, In the Golden State, dwindling water resources are increasingly a source of conflict. This ban was brought about due to the persistence of DDT in many different ecosystems, leading to high accumulations of the substance in many birds of prey. Some countries outside the United States still use DDT to control of mosquitoes that spread malaria. Q3.13. Fill in each blank with the correct vocabulary term. Q5.2. DDT was so widely used because it was effective, relatively inexpensive to manufacture, and lasted a long time in the environment. All four reports recommended an orderly phasing out of the pesticide over a limited period of time. Q2.4. A researcher observed that lizards living in areas with predatory birds have longer horns than those in areas with no predatory birds. On December 2, 1970, major responsibility for Federal regulation of pesticides was transferred to the U.S. Environmental Protection Agency (EPA). After reconsideration of the March order, in light of a scientific advisory committee report, the Administrator later reaffirmed his refusal to suspend the DDT registrations. What is the expected frequency of heterozygotes, based on your null model? In 1967, the Environmental Defense Fund, the National Audubon Society, the National Wildlife Federation, the Izaak Walton League, and other environmental groups joined the movement to restrict the use of DDT through legal action at both the local and federal levels. Please click here to see any active alerts. Many students predict that the snail shell thickness would still evolve even without variation because the snails need protection against predatory crabs. As many years went by, the environment changed such that the aquatic food sources were much more plentiful than those on land. 3. DDT Insecticide . This site is part of the Natural News Network 2012 All Rights Reserved. DDT and its related chemicals persist for a long time in the environment and in animal tissues. In 1945, DDT was released for commercial sale and became widely used for insect control in crop and livestock production, institutions, homes, and gardens. Did the change in this hypothetical example happen for the same reason as the change in shell thickness when you were playing crab? DDT is a possible human carcinogen according to U.S. and International authorities. Considered a general insecticide, DDT kills everything from beetles and lice to fleas and houseflies. . Which statements below are TRUE when a gene is at Hardy-Weinberg equilibrium? DDT is an insecticide that was used extensively in agriculture in the mid-1900s to kill many insect pests, including the boll weevil (pictured below), another pest of commercial cotton. As a direct result of eggshell thinning, these eggs were easily broken, causing a significant population decline. If the cystic fibrosis allele protects against tuberculosis the same way the sickle-cell allele protects against malaria, then which of the following should be true of a comparison between regions with and without tuberculosis? Why Wont the EPA? DDT's insecticidal action was discovered by the Swiss chemist Paul Hermann Mller in 1939. The effects continue. DDT was widely used during World War II to protect soldiers and civilians from malaria, typhus, and other diseases spread by insects. National Pesticide Information Center (NPIC) DDT Factsheets. CDC twenty four seven. Saving Lives, Protecting People, https://www.epa.gov/ingredients-used-pesticide-products/ddt-brief-history-and-status, Centers for Disease Control and Prevention, Section 2: Biomonitoring helps to shape policies that affect our health, Section 3: Biomonitoring teaches us about nutrition, Section 4: Biomonitoring helps us respond to health emergencies, Section 5: Learn more about biomonitoring, Dioxins, Furans and Dioxin-Like Polychlorinated Biphenyls, NNAL (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol), Organophosphorus Insecticides: Dialkyl Phosphate Metabolites, Per- and Polyfluorinated Substances (PFAS), Polybrominated Diphenyl Ethers (PBDEs) and Polybrominated Biphenyls (PBBs), U.S. Department of Health & Human Services. Many people mistakenly assume that DDT is no longer in use. These cookies perform functions like remembering presentation options or choices and, in some cases, delivery of web content that based on self-identified area of interests. The Case of DDT: Revisiting the Impairment Background The fact that DDT (or dichloro-diphenyl-trichloroethane) played a role in the decline of bald eagle and other bird-of-prey populations (e.g., ospreys, brown pelicans) is now commonly appreciated among most biologists. Many students predict that the snail shell thickness will evolve even without heritability because the snails adapt and grow thicker shells to escape from crab predation. Because they are used in agriculture and food production, pesticides are present at low levels in many of our diets. Previous findings showed that daughters of the women who had more DDT in their blood had a much heightened risk for breast cancer and increased prevalence of obesity, while sons had heightened risks for testicular cancer. Which hypothesis below is best supported by your data? The EPA Administrator further announced that no suspension of the registration of DDT products was warranted because evidence of imminent hazard to the public welfare was lacking. Is there any variation in shell thickness among the snails now? Headache, dizziness, nausea, vomiting, incoordination, tremor, mental confusion, hyperexcitable state. ddt-is-an-insecticide-that-was-used-extensively-quizlet 939c2ea5af ddt is an insecticide that was used extensively quizlet, ddt is an insecticide that was used extensively in the mid-1900s to kill mosquitoes quizlet https://williamheald226kff . World War II propaganda poster featuring a soldier applying DDT.t. Suppose the frequency of homozygous HbA/HbA individuals is 0.01 and the frequency of heterozygous HbA/HbS individuals is 0.18. They argue that DDT is a persistent, toxic chemical which easily collects in the food chain posing a proven hazard to non-target organisms such as fish and wildlife and otherwise upsetting the natural ecological balance. This treaty is known as the Stockholm Convention on POPs. If the frequency of HbS is 0.1, then what is the expected frequency of HbA/HbS heterozygotes? EPA works with other agencies and countries to advise them on how DDT programs are developed and monitored, with the goal that DDT be used only within the context of programs referred to asIntegrated Vector Management. What is your observed p (frequency of HbA) at 100 generations? Colombia to Resume Fumigating Its Coca Fields With Glyphosate, Missouri Farmer Wins $265 Million Verdict Against Monsanto. Frequent questions. %PDF-1.3 The information on this site is provided for educational and entertainment purposes only. It is very toxic to aquatic life, with-long lasting effects.This substance is reasonably anticipated to be a human carcinogen based on evidence of carcinogenicity in experimental animals. No. q=+100.kJ,w=65kJq=+100 . In addition, some animals exposed to DDT in studies developed liver tumors. Q1.4. Since then, studies have continued, and a relationship between DDT exposure and reproductive effects in humans is suspected, based on studies in animals. Use the histogram to answer: How many snails in the sample had shell thickness = 13? There is no selection. What can you conclude from the researcher's results? This treaty is known as the Stockholm Convention on POPs, which only allowed use of DDT for controlling malaria. Cookies used to track the effectiveness of CDC public health campaigns through clickthrough data. Why didn't this happen? She holds a Bachelor of Science in Microbiology with a minor in Health Management and Policy. When you eliminated malaria from the village, malaria deaths ceased (or should have). The fact is that is not true, Blumberg said. Which of the following statements is FALSE? The appeals were consolidated in the U.S. Court of Appeals for the District of Columbia. Effects of contact with DDT or inhalation may be delayed. Why didn't you see this in your experiment? If p represents the frequency of HbA, what is the expected frequency of HbA when the observed frequency of HbS/HbS is 0.83? DDT was also used in buildings for pest control. DDT (dichloro-diphenyl-trichloroethane) was introduced in the 1940s as a highly effective insecticide designed to combat the spread of malaria, typhus, and other diseases carried by insects. . w/T,8-iP*=# `VL\|bn /fJ;(c2o!1#zdrp%C; OnT (Zh^M Q5.8. As public concern grew, numerous environmental organizations joined the fight. Because of the decision not to suspend, companies were able to continue marketing their products in interstate commerce pending the final resolution of the administrative cancellation process. DDT exposure in people On warm summer nights, trucks carrying DDT would roll down residential streets, fogging entire neighborhoods with the chemical to combat mosquitoes. Q1.8. "DDT and Its Derivatives." It is not intended as a substitute for professional advice of any kind. D)F Exposure to DDT did not end when the chemical was banned in the United States almost 40 years ago. The hypothesis that longer horns offer greater protection against predation is NOT supported. 1656-1663., doi:10.1289/ehp.0900785. FrQ&';Jm%}W#'"~Jz@sd=*9o ykoI cnvu N {9c@k=+sP:GSh"*E`6o-z@CNL\ wAGk/v[mvu They help us to know which pages are the most and least popular and see how visitors move around the site. "Dichlorodiphenyltrichloroethane (DDT): Ubiquity, Persistence, and Risks." Q6.4. ((d~ x*GpQhJI^[HlJL q0>2Abt"Aepb2P|,K%X Turusov, Vladimir, et al. Due to this bioaccumulation, DDT remains in the food chain. According to the Centers for Disease Control, in 2020 an estimated 241 million cases of malaria occurred worldwide and 627,000 people died, mostly children in the African Region. DDT can convert into DDE, and both persist in body and environment. Although warnings against such hazards were voiced by scientists as early as the mid-1940s, it was the publication of Rachel Carson's book Silent Spring in 1962 that stimulated widespread public concern over use of the chemical. The EPA banned DDT in 1972 after an accumulation of research showing harmful impacts to wildlife and potential human health risks, and its now classified as a probable human carcinogen. A population that has no variability in a heritable trait will only evolve if, There are mutations in the genes for that trait. Even though thicker-shelled snails were less likely to be eaten by carbs, their offspring had random shell thicknesses, so the population can't evolve. The population is not evolving due to any of the conditions that disrupt Hardy-Weinberg equilibrium. DDT use was outlawed except under emergency conditions in Illinois, Iowa, Massachusetts, New Mexico, New York, Rhode Island, Vermont, and Wisconsin. The null hypothesis is supported: There is no evidence of a heterozygote advantage. The Administrator based his decision on findings of persistence, transport, biomagnification, toxicological effects and on the absence of benefits of DDT in relation to the availability of effective and less environmentally harmful substitutes. In August 1970, in another major action, USDA canceled Federal registrations of DDT products used as follows: (1) on 50 food crops, beef cattle, goats, sheep, swine, seasoned lumber, finished wood products and buildings; (2) around commercial, institutional, and industrial establishments including all nonfood areas in food processing plants and restaurants, and (3) on flowers and ornamental turf areas. DDT (molar mass = 354.49 g/mol) was a widely used insecticide that was banned from use in the United States in 1973. Truth Publishing assumes no responsibility for the use or misuse of this material. The principal parties to the hearings were various formulators of DDT products, USDA, the EDF, and EPA. 2, 2002, vol. In severe cases: convulsions, seizures, coma and respiratory depression. While it is effective as an insecticide, its potent toxicity isn't limited to insects. Q3.7. Centers for Disease Control and Prevention. Laboratory animal studies show DDT exposure can affect the liver and reproduction. AFTER malaria is cured, the frequency of the HbS allele should decrease in regions with lots of mosquitoes because: Having one copy of the HbS allele will no longer be advantageous in these regions. This long-term bioaccumulation, as it is called, means that over time, levels of DDT are highest in humans and larger predatory animals, especially meat-eating birds like eagles, hawks, condors, etc. Q2.3. DDT is one of 12 pesticides recommended by the WHO for indoor residual spray programs. Since the introduction of DDT for mosquito control in 1946, DDT resistance at various levels has been reported from more than 50 species of anopheline mosquitoes, including many that spread malaria. The relative fitness advantage to being heterozygous depends on the chance of being exposed to malaria. Farmers used DDT on a variety of food crops in the United States and worldwide. During the 30 years prior to its cancellation, a total of approximately 1,350,000,000 pounds of DDT was used domestically. Fry, D. M. "Reproductive Effects in Birds Exposed to Pesticides and Industrial Chemicals." Grizzly Bears Are One Step Closer to Losing Federal Protections, Privacy Policy/Your California Privacy Rights. While the EPA lists DDT as a class B carcinogen; this classification comes mainly as a result of animal studies as opposed to human studies. 103, no. Areas with more precipitation will have lower frequencies of the HbA/HbS genotype. Cohn said she fears that we wont learn until decades from now about chemicals being used widely today that could be doing irreparable harm to our health. Opponents to DDT, admitting that there may be little evidence of direct harm to man, emphasize other hazards connected with its use. An estimated 5,000 metric tons of DDT were used for disease vector control in 2005, although current levels of DDT production and storage are often difficult to track. CDC scientists measured DDT and its metabolite DDE in the serum (a clear part of blood) of 1,956 participants aged 12 years and older who took part in CDCs National Health and Nutrition Examination Survey (NHANES) during 20032004. The order did not affect public health and quarantine uses, or exports of DDT. Share sensitive information only on official, secure websites. DDT was initially used by the military during World War II to control malaria, typhus, body lice, and bubonic plague. Variation Heritability It is random. "Dichlorodiphenyltrichloroethane (DDT)." The use of DDT is banned in many countries, like the U.S., but it is still used (legally or illegally) in some places. Study with Quizlet and memorize flashcards containing terms like European green crabs preferentially eat periwinkle snails with which characteristic?, In Robin Seeley's studies of periwinkles on Appledore Island, what crucial evidence did she NOT have for evolution of shell thickness by natural selection?, A population that has no variability in a heritable trait will only evolve if and more. DDT can be absorbed by eating, breathing, or touching products contaminated with DDT. If the frequency of HbA homozygotes is 0.1, what is the value of p2? Q3.18. The use of DDT is banned in many countries, like the U.S., but it is still used (legally or illegally) in some places. Environmental Protection Agency. Join today. Sign up for email updates on nature, environmental politics, living well, and doing good. Someone has handed you the following graph of changes in the frequency of one allele in a population over time. International Programme on Chemical Safety. 1940s DDT was used as the first modern synthetic insecticide to control insect in agriculture, housing, institutes and to combat . A .gov website belongs to an official government organization in the United States. Q5.9. You will be subject to the destination website's privacy policy when you follow the link. Why or why not? Flat periwinkle shell thickness affects periwinkle survival when crab predators are present. DDT is an _____ insecticide. Injustices Throughout History and Today, 12 Plants That Repel Unwanted Insects (Including Mosquitoes), Everything You Need to Know About Animal Testing for Cosmetics, The Great Pacific Garbage Patch: Overview, Impacts, and Solutions. Q6.8. Also known as dichloro-diphenyl-trichloroethane, it is one of the most effective yet controversial synthetic insecticides ever developed. However, the Stockholm Convention on POPs did not ban its use entirely. On October 21, 1972, the Federal Environmental Pesticides Control Act, a far-reaching amendment to the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) was enacted. The HbS allele is more likely to persist in wetter regions because the relative fitness of HbA/HbS heterozygotes is higher where there is more malaria. Q1.2. If you need to go back and make any changes, you can always do so by going to our Privacy Policy page. Throughout the last decade, proponents and opponents of DDT have faced one another in a growing series of confrontations. Q3.2. In the body, DDT converts into several breakdown products called metabolites, including the metabolite dichlorodiphenyldichloroethene (DDE). Q3.25. A famous example of biomagnification is with the pesticide known as DDT. On the basis of information acquired during these sessions, the Administrator concluded that the potential for an economic emergency existed in 1974 and that no effective alternative to DDT was available. Which of the following is evidence that malaria creates a heterozygote advantage at the Hb locus? They then pass this mutation to their offspring. The pesticide was considered safe enough to be sprayed widely through US towns. (Suspension, in contrast to cancellation, is the more severe action taken against pesticide products under the law.) The findings support the theory thatgrandmother exposures to DDT could have contributed to a dramatic increase in obesity seen today in young adult women, and that exposure to DDT just before or after birth is associated with breast cancer risk factors for at least three generations, according to the study. sprouts, corn, and other crops (3). Ducks are aquatic birds. Following exposure to high doses, human symptoms can include vomiting, tremors or shakiness, and seizures. In areas where malaria is undeterred by other insecticides, DDT may be the only way to control mosquito populations and reduce fatalities from malarial disease. DDT (Dichloro-diphenyl-trichloroethane), for many years one of the most widely used pesticidal chemicals in the United States, was first synthesized in 1874. DDT is an insecticide that was used extensively in the mid-1900s to kill mosquitoes. Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website. We need more and more thorough testing to exclude carcinogens from use and better protect public health, Brody said. What changes occur gradually over time that indicate the population is evolving? The early popularity of DDT, a member of the chlorinated hydrocarbon group, was due to its reasonable cost, effectiveness, persistence, and versatility. In regions where malaria does not occur, individuals who are heterozygous HbA/HbS have a fitness advantage over those who are homozygous for the normal hemoglobin allele (HbA). DDT and Malaria. Finding measurable amounts of DDT and DDE in serum does not imply that the levels of these chemicals cause an adverse health effect. Cost, ease of use, species of mosquito, and chemical resistance all play a part in a countrys decision on which insecticide to choose, however, the final factor is whether or not the chosen product works to reduce disease. Assume that a population of one of these finch species is undergoing evolution by natural selection with respect to beak size and shape. 2022-06-30; wreck on 1942 crosby, tx today In March 1971, EPA issued cancellation notices for all registrations of products containing TDE, a DDT metabolite. Which of the conditions for natural selection are met by the populations in the experiment you just conducted? Public concern further manifested itself through the activities of various environmental organizations. DDT is one of the most controversial chemical compounds in recent history. 7NJe^z0A[~D2|CkQ>Unfs4\yEwEyD]eq\U@7" By clicking Accept All Cookies, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts. We are flooding the world with chemicals that may have the capacity to cause harm years down the road, and are not devoting enough research funding to track the impacts, Cohn said in an interview withSierra. Many other chemicals are now known to be EDCs, and both Cohn and Brody said we could head off many health problems by curtailing use. DDT can cause damage to the organs through prolonged or repeated exposure. 125-128., doi:10.1289/ehp.02110125, van den Berg, Henk. Use the following passage to answer the next three questions. DDT is a synthetic insecticide belonging to a class of chemicals called organochlorides. Thank you for taking the time to confirm your preferences. An official website of the United States government. ddt is an insecticide that was used extensively quizlet ddt is an insecticide that was used extensively quizlet. Blood serum levels of DDT and DDE in the U.S. population appear to be five to ten times lower than levels found in smaller studies from the 1970s. DDT is a synthetic insecticide belonging to a class of chemicals called organochlorides. Theresearch, which was published April 14 intheCancer Epidemiology, Biomarkers & PreventionJournal, is the latest in a series of findings generated from a relatively unique study that began in the 1960s, when DDT was widely used. Which population size is most affected by genetic drift, assuming the population does not become fixed for one allele? DDT (Dichloro-diphenyl-trichloroethane), for many years one of the most widely used pesticidal chemicals in the United States, was first synthesized in 1874. Are these changed consistent in direction and magnitude? A week long investigation in September 1973, a technical seminar on November 16, 1973, and a series of hearings in January 1974, aided EPA is reassessing the need for DDT. The decline in DDT usage was the result of (1) increased insect resistance; (2) the development of more effective alternative pesticides; (3) growing public concern over adverse environmental side effects; and (4) increasing government restrictions on DDT use. DDT was used to control pests like mosquitoes, houseflies, body lice, Colorado beetles, and gypsy moths. After the war, DDT continued to be used to control disease, and it was sprayed on a variety of agricultural crops, especially cotton. Which snail population has the larger range of variation in shell thickness? In 1972, EPA issued a cancellation order for DDT based on its adverse environmental effects, such as those to wildlife, as well as its potential human health risks. There is no change in shell thickness within the population. Robin Seeley designed her experiment to test the hypothesis that crab predation resulted in differential survival among these snails. Because the carbs preferred thinner-shelled snails, all the snails in each new generation had thicker shells than their parents. USDA further announced its intention to discontinue all uses nonessential to human health and for which there were safe and effective substitutes. Whoops! Crab predation does not result in differential survival, because compared to thin-shelled snails, thick-shelled snails are more likely to survive in the presence of crabs. DDT (dichloro-diphenyl-trichloroethane) was developed as the first of the modern synthetic insecticides in the 1940s. ks xI,jr 3'qulMm84]N>0UbP*''(No3ANN?BxZ@ &PS(-W;(I[jwN L/iUPYvA YBy*]|OBequ+m: 9:W0 . Where is the malaria prevalence the highest? A Billy Mitchell bomber skims the housetops in Rockford, Illinois, on August 19, 1945, as it sprays DDT. These ducks spent time on both land and water. DDT is an insecticide that was used extensively in the mid-1900s to kill mosquitoes. In which population were allele frequencies most stable, considering both long-term (from the beginning to the end) AND short-term (from one generation to the next) changes? +A*}O20 The Federal Government has not been oblivious to the hazards of DDT use as is indicated by various Government studies and actions undertaken since the late 50s. The population should now have only thick-shelled snails. By the end of 1949, more than 4,650,000 house spray applications had been made. In addition, long-term buildup of DDT in meat-eating birds like the bald eagle resulted in reproductive complications as well.