Aldrin and dieldrin.

Date:
[between 1940 and 1960?]
Catalogue details

Licence: Public Domain Mark

Credit: Aldrin and dieldrin. Source: Wellcome Collection.

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    Led 1.5 ues Alkali Resistance: Alérin and dieldrin, and formulations of these insecticides, are, unlike other chlorinated hydroearbons, stable in the presence of alkalis. The instability of the commonly used chlorinated hydrocarbons in contact with, for instance, lime, and the con- sequent deterioration of biological activity is.a serious practical disadvantage. Aldrin and dieldrin, on the othér hand, are com- pletely impervious to the action of alkaline reagents and, under conditions of practical use, are unaffected by acidic reagents, Lack of Tainting Drawbacks Neither aldrin nor dieldrin has caused tainting in root crops grown in soil to which these chemicals have been applied. Among the crops tested in this respect are potatoes, turnips, carrots, onions, Furthermore, neither of the insecticides are trans- located by plants, and thus there is no deposition of harmful quantities of these substances in plant tissue. Aldrin and Dieldrin Harmless to Soil Micro-organisms : At the doses recommended for the control of soil pests, neither aldrin nor dieldrin show harmful effects on micro- organisms found in the soil, Tests are proceeding to determine the dose level at which such organisms are harmed: the indicatims are that this level will be far above the dose level required for practical insect control. Phytotoxicity: Both aldrin and dieldrin applied as commercial sprays have controlled insects without, in any way, damaging crops. Experiments carried out in South Africa have shown that neither aldrin nor dieldrin, in wettable powder or emulsion form, will affect the germination of maize seeds, and there is a large body of evidence from overseas usage to show that, unlike other chlorinated hydrocarbon insecticides, the new compounds are not injurious to any farm or garden crops, including Cucurbits. Lh fee ox Page 3/....
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