April 1947 E-720 UBRaRY tfrj^n? PLANT BOARD United States Department of Agriculture Agricultural He search Administration Bureau of Entomology and Plant Quarantine NICOTINE INSECTICIDES. PART III— BUST CARRIERS TOR NICOTINE By I* L. Mayer, Division of Control Investigations, Bureau of Intomology and Plant Quarantine, and Florence B. Talley and C. 7. Woodward, Eastern Regional Research Laboratory, Bureau of Agricultural and Industrial Chemistry 1/ This is the third of a series of investigations on nicotine insecticides conducted by this Bureau in cooperation with the Bureau of Agricultural and Industrial Chemistry. Part I of this series (£-646 issued in 1945) reported a study of complex salts containing nicotine, usually combined with a metal, and Part II (1-709 issued in 1946) described tests with a large number of mate- rials to find activators for nicotine. The purpose of the present study was to determine the effect of various carriers on the tox- icity of dusts or sprays containing nicotine sulfate. As before, the materials tested were prepared at the Eastern Regional Research Laboratory of the Bureau of Agricultural and Industrial Chemistry, for testing against pl?nt-feeding insects by the Bureau of Intomology and Plant Quarantine £t its Sanford, 71a* , laboratory. Previous investigations by Headlee and Rudolfs (£, 4) and by Thatcher and Streeter (9j have shown that there are three types of dust carriers for nicotine or nicotine sulfate* (1) "Adsorbent" carriers, which tend to prevent the volatilization of nicotine: (2) "inert" carriers, which merely expose large surface areas; and ( 3) "active" carriers, which liberate nicotine from its salts by chemical action. Examples of these types are bentonite, pyrophyllite, and dolomite, respectively. These early studies were concerned large- ly with the control of aphlds, and the active carriers were the most effective of the three types. It was further shown by De Ong (l) and Headlee and Rudolfs (3) that the toxicity of nicotine-containing dusts and sprays was directly proportional to the rate of nicotine evolu- tion. l/The authors are indebted to E. R. McGovran ( transferred to Office of Experiment Stations, November 3, 1946) and G. T. Bottger, Division of Control Investigations, for supervision of the entomologi- cal tests; and to J. J. Willaman, Eastern Regional Research Laboratory, for many valuable suggestions in this investigation. -3- The rola till cation of nicotine from duets vat affected 07 factors other than the type of carrier. Hicotins vat more readily lost from a coarse dust than from a fins one (g, 4) . In aphid con- trol a temperature of at least 70° P. vas required for satisfactory evolution of the alkaloid. Small amounts of vater hastened nicotine evolution from ths active carriers (4, 7, 9). In an attempt to increase the efficiency of nicotine dusts against several lepidopterout larvae, it vas deemed advisable to in- vestigate in a preliminary manner the effect of various carriers in ths dust mixtures. Accordingly 39 materials, selected to represent a vide range in particle sice, were obtained from commercial companies in March 1944. Particular attention vas directed to carriers that did not release nicotine from the sulfate, inasmuch as a lasting deposit of ths toxicant appeared desirable. Hovever, several active carriers vers included for comparison. A further objective of these comparisons vas to select a carrier which would be used as a standard in a largs number of dust mixtures employed in screening tests on nicotins deriva- tives and in the search for nicotine synergists. Characteristics which must bs considered to appraise fully the economic usefulness of carri- ers such as (Instability, drifting, packaging requirements, availability, and standardisation were not studied in the laboratory tests, further- more, no attempt was mads to evaluate any possible synergistic action of the carriers which gave the best 'results. This investigation was confined to preliminary observations of ths toxicity of the various nicotine dust mixtures to the melonworm ( Diaphania hyallnata (L.)) and the southern armyworm ( Prodenla erldaala . (Cram.)). Materials and Experimental Procedure All mixtures contained 5 percent of nicotine on the alkaloid basis. In the bentonite this was supplied by free alkaloid; in the others by nicotine sulfate. The 37 carriers studied, plus the 2 in the standard dusts, Pyrax ABB (pyrophyllite) (No. 38) and Volclay bentonite (No. 39), are listed la table 1. With the exception of Carolina pyrophyllite (No. 19), which vas approximately 200 mesh, all dusts were 300-325 mesh or finer. The pE of the carriers was determined by suspending 5 grams in 20 ml. of water and allowing the suspension to stand until a constant pB value vas reached. The pH of the carriers plus 5 psrcent of nicotine am the sulfate was determined in a similar manner. All readings warm aads with a flass-electrods pH meter. -3- The loss of nicotine was determined by cheaical analysis of the mixtures before and after 16 hours' exposure at 70° F. In these tests 2 grams of dust mixture was uniformly distributed on a square foot of glass area. Nicotine determinations were made by the silicotungstic acid procedure. The percentages of nicotine lost from the dusts con- taining 5 percent of nicotine as the sulfate are reported in table 1. Most of the dusts were tested against the first instar southern armyworm and the fourth-instar melonvom. The pulrerized limestone mixture, which was not of a dustable consistency, was restricted to spray tests. The testing procedure used was similar to that described by Swingle (8) and in Part I of this series. About 30 larvae were used in each test. The large larrae were placed on previously dusted pumpkin-leaf sections in 9-cm. petrl dishes and the small larrae in cloth-covered rials on dusted collard-leaf sections. Counts were taken at the end of the first, second, and third days. The test was terminated on the third day. A nicotine sulfate dust (nicotine 5 percent) in pyrophyllite (Pyrax ABB) was used as the standard of comparison. Some of the mix- tures that gave a higher mortality than the standard were tested in sprays and subsequently compared with nicotine bentonite. This work was not completed, however, because the entomological laboratory was transferred from Sanford, Fla., to Anaheim, Calif., where the melon- worm and the southern armyworm were not available. Discussion of Results Of the 37 materials tested as carriers for nicotine, 9 gave an increase in toxicity of more than 15 percent over the standard in at least one test ( table 2) • When compared with the Pyrax ABB (pyrephyllite) standard, the nicotine dusts that showed the highest mortalities of the southern armyworm were those containing magnesia talo, fuller's earth I 90-44B, talc No. 21, talc No. 23, fuller's earth X 90-44A, and fire clay* Against the melonworm the most effective carriers were Grand! te Bond, magnesia talo, and Cherokee clay. Pallor's earths X 90-44A and X 90-44B were slightly above the standard in tests on melonworm. Vhen used in spray a, pulverized limestone, fuller's earth X 90-44A, magnesia talc, Grundite Bond, and fuller's earth X 90-44B gave better results than the standard against the southern armyworm, and magnesia talc gave the best results against the melonworm* Of the carriers compared with bentonite, fire clay was the only material that showed up as possibly better, both in a dust and in a spray, against the melonworm. Grundite Bond was soaevhat better in a duat against the melonworm, while fuller's earth S 90-44A was better in a spray against the southern armyworm. All other materials were inferior to bentonlte in most tests. It should be noted that in the bentonite series nicotine sulfate is compared with what is usually considered to be a reaction product, namely, nicotine bentonite (5, 6). Both acid and alkaline materials are represented in the list of 9 best dust carriers. The clays are essentially acid; the pH of fire clay is 4, of Cherokee clay 6.1, and of Q-rundite Bond 5.97. The talcs and limestone are alkaline; talc No. 21 has a pH of 8.5, talc No. 2? of 8.55, magnesia talc of 8.95, and pulverized limestone of 8.89. The fuller 1 s earths, X 90-44A and I 90-44B, are somewhat less alkaline than the talcs, having pH values of 7.8 and 8*02, respectively. It is believed that the increased kills of the southern armyworm with some of these alkaline materials, especially limestone, may have been due to nicotine fumigation, as the cloth-covered vials in which the tests were carried out do not afford much ventilation. Of the 9 best dusts only 2 showed any great loss of nicotine dur- ing the 16-hour period of exposure. Pulverized limestone lost 98 per- cent of its nicotine, which was expected on the basis of previous find- ings. Talc No. 23 lost 27 percent and talc No. 21 lost 17 percent. The other 6 dusts lost only 1 to 9 percent of nicotine. It is recognized that the physical characteristics of the dusts may have influenced their effectiveness. The addition of enough nico- tine sulfate to give a dust containing 5 percent of nicotine in many cases resulted in a poorly dustable mixture with impaired efficiency. In this regard special mention should be made of the unique physical properties of fuller's earth 3 90-44B, mlneralogically known as attapulgite. It is a very light, fluffy material with a remarkable power to absorb liquids. Is much as 33 percent of mineral oil has been incorporated in this material without impairing its excellent dusting qualities. On the basis of these preliminary data we suggested that attapulgite be considered as a carrier for insecticides. 2/ Summary Thirty-seven materials were tested as carriers for nicotine sul- fate against the melonworm ( Dlaphanla hyallnata (L.)) and the southern armyworm ( Prodenla erldanla . ( Cram.)) . Nine materials appeared to 2/Since this manuscript was submitted, attapulgite has found ex- tensive commercial use as an Insecticide carrier. -5- produce higher kills than the pyrophyllite standard in at least one test. Three of thea, magnesia talc and fuller 1 s earths 1 90-44A. and I 90-44B, gare considerably higher kills against both insects in both dusts and sprays. Of the limited group compared with the bentonite standard, fire clay was as good or better, both in dusts and sprays, against the melonworm. Toller 1 s earth ] 90-44A was better in dusts against the aelonwora, and fuller 1 s earth 1 90-44B was better in sprays against the southern armyworm. The two standards were compared with each other in only one spray test, and in this case bentonite was better than the pyrophyllite (Pyrax ABB) against the armyworm. Insect mortality appeared to hare no well-defined relation to pfl or to nicotine rolatility, since acid and alkaline materials were represented among the 9 best materials, while only 2 of thea showed appreciable nicotine loss. Fuller's earth 1 90-44B, or attapulgite, is considered the best of the new materials tested because of its unique ability to absorb large quantities of liquid, either oil or water, and because of the high mortalities resulting from its use. -6- Table l.~pH values and nicotine retentiveness of duets used, as carriers. Carrier Supplier i/ : pH t pH of carrier : Nicotine lost : found : / 5 percent t after 16 hours' J 5 Qt aiflftllM i eXDOSUTS 1 Colloidal kaolin 2 Harmon clay 3 Peerless clay 4 Fillmore clay 5 Fire clay 6 Perry clay 7 Cherokee clay 8 Bancroft clay United Clay Mines* Trenton, N. J. do* R. T. Yaaderbilt Co., 230 Park At©., Hew York, N. Y. United Clay Mines Illinois Clay Products Co., Joliet, 111. United Clay Mines R. T. Vanderbilt Co* United Clay Mines 4.1 5.2 Percent 4.4 5 14 4.3 5.6 5.5 5.4 8.6 4.5 5.9 U.4 4.0 4.7 9.4 4.1 5.1 3.2 6.1 6.4 3.0 11.5 9 Top ton clay do. 4.6 5.1 16.3 10 Chicora J. J. Ruber, Inc., 4.6 4.9 clay 460 W. 34th St., New York, N. Y. 11 Gypsum National Gypsum Co., York, Pa. 7.3 6.6 20.3 12 Walnut shell Agicide Laboratories, 4.8 5.0 12.6 flour 4668 N. Teutonia Ave., 13 Talc No. 21 14 Talc No. 23 Milwaukee, Vis. I. N. Richards Co., 8.5 1203 I. State St., Trenton, N. J. Eastern Magnesia Talc 8.6 Co., Burlington, 7t. 6.9 7.6 16.6 27.1 -7- Table 1. — Continued Carrier Supplier ]J i x x x pH : pH of carrier : Bicotine lost t found x / 5 perceat : after 16 hours' J i 9? ftAgotlae 1 exposure 15 Fibrous talc ( Loomkill) Loomis Talc Co., Couverneur, 5. Y. 9.1 16 Magnesia talc Xastern Magnesia Talc Co* 9.0 17 Yelret filler E Carbola Chemical Co,, Natural Bridge, B* T* 9.1 18 Micro Velra A do. 9*0 19 Carolina pyrophyllite Carolina Pyrophyllite Co., 10 X. 40th St., Bev York, B, T* 6*9 20 Grundite Boad Illinois Clay Products Co* 6*0 21 Puller' 8 earth X 90-44A Attapulgus Clay Co., Philadelphia, Pa* 7.8 22 Puller' ■ earth X 90-44B do. 8*0 23 Bauxite X 90-440 do* 6*5 24 Priaalte M3Z Butcher and Co., Los Angeles, Calif* 6*3 25 Priaaite DS do* «•* 36 Wyoboad beatoaite Vyodak Cheaical Co., 4600 X* 71st St., Clerelaad, Ohio 8*8 27 Tolclay beatoaite (Hlro) American Colloid Co., 362 V. Superior St., Chicago, 111* 8,8 28 Yolclay beatoaite (71 solo) do. 8*6 8.4 7.1 8.7 8.8 5.1 6*5 7.2 7*6 6*3 6*0 6*0 8*6 8*4 8.1 Percent 63*2 1.8 62*1 45*5 3.1 1.7 3.7 1.2 18*4 24*4 35.7 Table 1, — Continued -8- Carri er Supplier l/ : : : : pH : pH of carrier : Nicotine loet j found : / 5 percent : after 16 hours* Percent 29 Silene EF Batch 3-7-1 Pittsburgh Plate Glass Co., Columbia Chen* Dlv., 30 Rockfeller Plaza, New York, N.T. 8.8 8.8 30 Micronized Pyrax ABB do* 5.9 4.3 2.0 31 Ferasil ( Fly Ash) Corson Lime Co., Plymouth Meeting, Pa. 8.2 7.3 32 No. 2261 Florida land- pebble super- phosphate Baugh Co., Philadelphia, Pa* 2.9 3.1 11.0 33 Diluex Flo ri din Co., Warren, Pa, 7.9 7.0 9.5 34 Florigel do. 7.5 6.9 35 China clay Wagner Co., Philadelphia, Pa* 7.8 7.5 30.5 36 Pulverized limestone Corson Lime Co., Plymouth Meeting, Pa. 8.9 8.3 98.3 37 Magnesite do* 9.2 8.2 74.1 38 Pyrax ABB R. T. Vanderbilt Co. 7.6 6.6 6.0 39 Vol clay Wyoming bentonite Wagner and Co. 9.1 l/The address of each supplier is given only once in this table. _Q_ U © 4» "H it 4» a3 O U -d © P. M "8 a co d M r! rt co -h +> d o CO d « o o sr 9 •d »4 O O *rl 4» • O 4» © CB • a d •d tH © © 4» *» O O o o d d m co OS CO © © U © © CO © I > c • U 4» U « © © • CM o a X» -H 4 Eh 9 4» CO • 4» a o 4> 8 -d 4» o •H & o o •d 3 3 4» CO © 4» 5 ft o t-. >» p* XI 4» d o a o o a rH O © * 2 SB 2 & 4> CO ft © U 4 o to rH & in 5 © • o © XI o CM 02 CM N rH I cx> N I ! 4 ft a S I + + + CO FJ ft o CO &4 to o CO EH •d d © 4» I o H XI +» t-l © 00 to 1 1 1 1 1 fc o rH m rH 00 a 8 in • in 1 + + ♦ i + + I o w X) © © to in © d o © © N *H « > £ £ A« S 3 8 a ft 8 -10- Table 3. — Materials comparable to or poorer than the standard in most tests • : Southern i Melon- Carrier • • • armyvora worm 1 Colloidal kaolin + i/ 2 Harmon clay + - 3 Peerless clay - ♦ 4 Fillmore clay ♦ - 6 Perry clay ♦ - 8 Bancroft clay - - 9 Topton clay • - 10 Chicora clay - - 11 Gyp SUB ♦ - 12 Walnut ah ell flour - • 15 Fibrous talc (Loomkill) - - 17 Velvet filler E - — 18 Micro Velra A - + 19 Carolina pyrophyllite + + 23 Bauxite B90-44C - - 24 Frianite M3X - - 25 Frianite DS - - 26 Wyobond bentonite - + 27 Volclay bentonite (Hivo) «• - 28 Tolclay bentonite (Visclo) - - 29 Silene KF + - 30 Micronized Pyrax ABB - - 31 Ferasil ( Fly Ash) - - 32 No. 2261 Florida land pebble superphosphate — ~ 33 Diluex - - 34 Florigel - ♦ 35 China clay - - 37 Magnesite l/ + Slightly better than standard; - poorer than standard. -11- Literature Cited (1) De One, I. R. 1923, The relation between the volatility and toxicity of nicotine in sprays and dusts. Jour* Icon* Int. 16: 486-493. (2) 1943* Trianite, an insecticide diluent* Jour* Icon* lat* 36: 799-800. (3) Headlee, T. J* ( and Bndolfs, V, 1923* Some principles which underlie the making and use of nicotine dust. H* J* Agr* Erpt. Sta. Bui* 381, 47 pp. ( 4) and Rudolfs, W. 1924. Some further facts relative to the principles under- lying the asking and use of nicotine dust* IT. J. Agr* Ixpt* Sta* Bui. 400, 44 pp. (5) Smith, C. R* 1934* Base exchange reactions of bentonite and salts of * organic oases. Amer. Cheat. Soc* Jour. 56: 1561-1663. (6) 1937* Compound and process for making nicotine-bentonite compounds. (IT. S. Patent No* 2,096,566) TJ. S* Patent Office, Off. Gas* 4831 649. (7) Streeter, L* E* 1925* Influence of temperature and humidity upon the vola- tilization of nicotine from tobacco dust-lime hydrate mixtures* Jour* Icon* Int. 18: 590-593. (8) Swingle, M. C. 1943. Ixploring the insect icidal possibilities of new mate- rials. In Laboratory procedures in studies of the chemical control of insects, edited by 7* L* Campbell and 7. I* Moulton, Amer* Assoc. Adv* Sci., Pub* 20, pp. 82-84. Washington, D* C. (9) Thatcher, R. V., and Streeter, L. R. 1923. flaetors which affect the volatility of nicotine from Insecticide dusts* I. T* Agr* Bxpt. Sta. Bui* 501, 34 pp. UN.VERSITY OF Fl nom 3 1262 09239 1407