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J Mcdiarmid F Clark - One of the best experts on this subject based on the ideXlab platform.

  • eleanor ormerod 1828 1901 as an economic entomologist pioneer of purity even more than of Paris Green
    The British Journal for the History of Science, 1992
    Co-Authors: J Mcdiarmid F Clark
    Abstract:

    In 1924, Virginia Woolf wrote a short story based upon the life of Eleanor Ormerod. A wealthy spinster, Ormerod achieved notoriety in late nineteenth-century Britain as an economic entomologist. In 1904, Nature compared her to Caroline Herschel and Mary Somerville. In terms of recent scholarship devoted to the history of women in science, Ormerod's career differed markedly from that of her two predecessors. The emotional or intellectual support of a brother, husband, father, or male family relation made no considerable contribution to her commitment to the study of entomology. Furthermore, her life as an independent spinster offered no positive proof for Francis Power Cobbe's dictum: as she aged, Eleanor Ormerod showed no tendency to become a ‘women's rights woman’. She publicly accepted or internalized the dominant, masculine ideology of science; and by contemporary standards, she achieved success.

W D Hunter - One of the best experts on this subject based on the ideXlab platform.

Jerome Onsager - One of the best experts on this subject based on the ideXlab platform.

  • II.4 A Review of Chemical Sprays in Cooperative Rangeland Control Programs
    2015
    Co-Authors: Nelson R. Foster, Jerome Onsager
    Abstract:

    The chemical sprays used against rangeland grasshoppers today and the current cooperative rangeland grasshopper management program are both results of an evolving solution to an age-old problem. That problem is one of how best to control or suppress damaging populations of grasshoppers over widespread areas. The following chapter will review the history and evolution of chemical sprays in rangeland grasshopper control to the present day. History In the United States, the history of grasshopper control is interwoven with that of the Mormon cricket. Control was conducted primarily to protect crops, but rangeland also was treated to save forage and prevent insect migration to nearby cropland. During the first half of the 20th cen-tury, control relied almost exclusively on poison baits. Although sprays such as Paris Green and sodium arsenate were used, these compounds fell from favor because the poisoned vegetation endangered livestock (Parker 1952). Both State and Federal assistance were provided for orga-nizing and financing control efforts, particularly during outbreak years. In the late 1940’s and early 1950’s, several major devel-opments occurred that significantly changed the way grasshoppers were controlled. 1. Perhaps the most important was the development of the chlorinated hydrocarbon insecticides. They were extremely effective in small amounts against grasshop-pers. They could easily be formulated into baits, acted quickly, and had a longer residual effect than previously used baits. Because of these qualities, chlordane and toxaphene in 1949 and aldrin in 1951 quickly replaced previous baits (Parker 1952). 2. Large-scale (thousands of acres) aerial application of bait became more commonplace. Compared to older wet baits, the new compounds could be formulated dry, which made distribution easier. In Montana and Wyoming during 1949–50, aerial application of chlor-dane and toxaphene baits were the major tools used against grasshoppers (Parker 1952). 3. Sprays of these compounds were also developed at the same time. In addition to being extremely effective, they were much cheaper than baits. Sprays of chlordane, tox-aphene, and aldrin first were used in grasshopper control programs in 1947, 1948, and 1950, respectively (Parke

Nelson R. Foster - One of the best experts on this subject based on the ideXlab platform.

  • II.4 A Review of Chemical Sprays in Cooperative Rangeland Control Programs
    2015
    Co-Authors: Nelson R. Foster, Jerome Onsager
    Abstract:

    The chemical sprays used against rangeland grasshoppers today and the current cooperative rangeland grasshopper management program are both results of an evolving solution to an age-old problem. That problem is one of how best to control or suppress damaging populations of grasshoppers over widespread areas. The following chapter will review the history and evolution of chemical sprays in rangeland grasshopper control to the present day. History In the United States, the history of grasshopper control is interwoven with that of the Mormon cricket. Control was conducted primarily to protect crops, but rangeland also was treated to save forage and prevent insect migration to nearby cropland. During the first half of the 20th cen-tury, control relied almost exclusively on poison baits. Although sprays such as Paris Green and sodium arsenate were used, these compounds fell from favor because the poisoned vegetation endangered livestock (Parker 1952). Both State and Federal assistance were provided for orga-nizing and financing control efforts, particularly during outbreak years. In the late 1940’s and early 1950’s, several major devel-opments occurred that significantly changed the way grasshoppers were controlled. 1. Perhaps the most important was the development of the chlorinated hydrocarbon insecticides. They were extremely effective in small amounts against grasshop-pers. They could easily be formulated into baits, acted quickly, and had a longer residual effect than previously used baits. Because of these qualities, chlordane and toxaphene in 1949 and aldrin in 1951 quickly replaced previous baits (Parker 1952). 2. Large-scale (thousands of acres) aerial application of bait became more commonplace. Compared to older wet baits, the new compounds could be formulated dry, which made distribution easier. In Montana and Wyoming during 1949–50, aerial application of chlor-dane and toxaphene baits were the major tools used against grasshoppers (Parker 1952). 3. Sprays of these compounds were also developed at the same time. In addition to being extremely effective, they were much cheaper than baits. Sprays of chlordane, tox-aphene, and aldrin first were used in grasshopper control programs in 1947, 1948, and 1950, respectively (Parke

Chris Cooksey - One of the best experts on this subject based on the ideXlab platform.

  • health concerns of heavy metals and metalloids
    Science Progress, 2012
    Co-Authors: Chris Cooksey
    Abstract:

    ABSTRACT There is a long history and an overwhelming amount of data on the toxicity of heavy metal compounds. Here a brief look is taken of some aspects of the toxicity of lead, cadmium, mercury and arsenic, chosen for their historical importance and environmental significance, highlighting especially the contrast between the acute and chronic toxicity of purely inorganic species and their organic derivatives. For further details of other toxic metal compounds, the reader might like to consult "Elements of murder: a history of poison" by John Emsley (2005, Oxford University Press). Keywords: toxicity of lead, cadmium, mercury and arsenic, environmental poison Acute and chronic toxicity Sometimes the distinction between acute toxicity and chronic toxicity is not very clear; but generally acute toxicity is the result of a single exposure leading to illness or death, whereas chronic toxicity is the result of long-term exposure leading to illness or death. A measure of acute toxicity was originally developed to test the strength pharmaceutical preparations which could not be measured by chemical means, for example, digitalis. Foxglove preparations have been used medically since the eighteenth century, sometimes with dire consequences because the concentration of the active principal, digitalis, depends on the quality of the plant and the efficacy of the extraction process. The difference between the dose required for a medical effect and that which could prove fatal is not large. A measure of the acute toxicity of pharmaceutical preparations was devised by Dr John William Trevan (1887-1956) a pharmacologist who was director of the Wellcome Research Laboratories until he retired in 1953. In this test, a number of rats were given various single doses of the test material and from the number who died within a day or two a figure of the median lethal dose, LD50, could be determined (1). Typical values for LD50 are shown in Table 1. It may be a surprise that cadmium sulfide is less toxic than sodium chloride, but that is only due to its low solubility; more noteworthy is that mercury(I) compounds are 200 times less toxic than mercury(II) compounds. Some idea of the human toxicity of the compounds in the list can be can be gained by multiplying the LD50 value by the weight of a standard adult male, 60 kg in the EU or 80 kg in the USA. For many years it was customary to convert the numbers into words, using the Hodge and Sterner Scale (1949), which could then be used on labels (Table 2) (2). This has been replaced, in Europe, by the Globally Harmonised System of Classification and Labelling and Packaging of Chemicals which is much simpler (Table 3) (3). Arsenic Arsenic has been known from antiquity to be toxic and is popularly associated with accidental or deliberate poisoning leading to death. It was widely available until the mid-twentieth century and was used as a pesticide against rats but is now replaced by thallium or warfarin. The use of arsenic, as the oxide, in taxidermy to preserve specimens from insect attack was introduced by Jean-Baptiste Becoeur (1718-1777) and was in use in museums until the 1980s (4). A related use of arsenic compounds is as a herbicide: Agent blue was one of the rainbow herbicides used against Vietnam to destroy rice paddies (5). Agent blue is a mixture of cacodylic acid (dimethylarsinic acid) and its sodium salt. There was a significant use of coloured arsenic compounds by artists in painting (orpiment, [As.sub.2][S.sub.3], realgar, [As.sub.4][S.sub.4]) and in wallpaper (Scheele's Green, copper arsenite, CuHAs[O.sub.3] and Schweinfurt (or Schweinfurth) Green, also termed Paris Green, Vienna Green, or emerald Green (copper acetoarsenite, 3CuO x [As.sub.2][O.sub.3] x Cu[OOC x C[H.sub.3]]). The concern about the extent of accidental or deliberate poisoning in the nineteenth century led to the passing of the Arsenic Act (1851) which required a signature for the purchase of arsenic compounds (6). …