The Sciences: Chemistry:

Pest Control Research:

Consequences of the Complete Ban of some Synthetic Insecticides: Less Chemical Pest Control

By Professor Dr.Dr.h.c. Randolph Riemschneider

Berlin, Germany

In the article “Chlorine chemistry for pest control research” (1) repeated the author again his warnings (2) - given already many years ago in several lectures - against the complete banning the use of synthetic chlorine compounds like DDT which stopped then succesfully the malaria. Discussions coming up by the mentioned essay (1) caused the following paper which could be entitled also: “Millions of malaria cases after DDT ban following Rachel Carsons suggestion (3)”. The author trod different ways “Less chemical pest control.”

The damages caused by insects in the world every year are immeasurable and are best characterised by bons mots of a few entomologists, for example:

„We do not harvest what we sow, but rather what the insects leave over for us” (Stellwaag)

“Ninety-nine percent of us believe we live in the human age. We are still in the epoch of insects and trying to attain the human age in the fight against insects” [Howard (4)].

Chemical, physical and biological methods are used for pest control.

The success achieved with chemical agents such as insecticides on the basis of halogen compounds and phosphoric acid esters in the nineteen forties and sixties is indisputable and has saved millions of human lives, for instance:

Example 1: Use of DDT and DDD for controlling the malaria mosquito and its total extermination at the time, recognised by the award of the Nobel Prize in Medicine for DDT in 1948

Example 2: After the 2^nd World War, E 605 saved the rice harvests in Japan and saved many Japanese from starvation. This is why a monument was erected in Japan for E 605: see photograph on the page after next.

We owed DDT and other synthetic pesticides an unprecedented reduction in malaria transmitted by Anopheles mosquitoes:

There were approx 2.5 mio cases of malaria in Ceylon (now Sri Lanka) in 1947-49, before the use of DDT, in 1962-63 there were only 100 meaning the malaria disease was completely defeated then!

After the complete ban of synthetic insecticides there were in 1969 already over 2 mio new malaria cases in Ceylon: Table 1.

Table 1:

The malaria prognosis diagram from 1998 for the years 1989 – 2010 is alarmig, the number of deaths is rinsing again worldwide:

Diagramm 1:

The author warned over and over again in time against a complete ban of the mentiond insecticides in his lectures in the fifties, and recommended a middle course under the premise and the target “less chemical pest control”.

Publications with overdone interpretations like the book “Silent spring” by the nature protection writer Rachel Carson in 1962 and unwise ill-considered talking bigs of Green people are responsible for many millions of malaria cases and deaths between 1969 and now; in Africa for instance more than 1 mio children in an age under 5 years died annually according to recent News Paper reports (15).

The aforementioned lady propagated an absolute prohibition of DDT (3).

The author delivered to Ms Carson on her requests in 1949 and 1951/52 comprehensive material about synthetic insecticides (5-8, 14) and gave in these papers also early criticism of any improper and unneccesary use and their consequences (9-13). Unfortunately the aforementionated writer did not quote any of these papers (listed in SPECIAL PART A) in her 1962-book.

The author drew Ms Rachel Carson’s attention to her unprofessional conduct but in view of her poor state of health refrained from taking legal action: Carson case in the SPECIAL PART A).

Any responsible scientist who has anything to do with chemical pest control will immediately reflect on the problems linked with the widespread use of chemical toxicants. So from 1948, the author trod other paths with respect to pest control, parallel to his own work on insecticides containing halogens and recommended “ less chemical pest control” meaning: Opposite of widespread use of large quantities of synthetic toxins like halogen and phosphorous compounds. Hardly possible to forgo chemistry completely.

«Mit etwa „Gebt uns synthetische Insektizide wie DDT zurück“ hat 2007 der Generaldirektor der Gesundheitsbehörden Ugandas seinen Hilferuf in „Wall Street Journal“ überschrieben: Es hat sich gezeigt, dass sich die Gefahren für Mensch und Umwelt als eher geringfügig herausgestellt haben, obwohl DDT früher mit Flugzeugen zu Tausenden von Tonnen flächendeckend als Insektizid über die Felder ausgebracht wurde – eine Anwendung, die heute nirgendwo zur Debatte steht. Heute ginge es darum, das Insektizid in grossen zeitlichen Abständen und wohldosiert zu sprühen, was die meisten Entwicklungshelfer vor Ort und auch derzeit die afrikanischen Gesundheitspolitiker für das einzig wirksame Mittel gegen Malaria halten» , zitiert nach (15).

Foto: Monument to E 605 in Japan

Author thanks BAYER’s Kekulé Library for permission to use the photo

Under the titel „Critical comments on chemical pest control and ways to reducing it” the author had drawn in his book (2) the attention to the toxicological dangers for humans, animal and plants as well the problems of resistance and discussing the possibility of a negative influence on the food chain; insect – bird, reptil - mammal [1948-50 (9-13)]. The ready solubility of halo compounds in lipoids facilitates accumulation in fat tissues via the food chain, with humans at the end of it; cf. also SPECIAL PART F).

Scant notice was given to the phenomenon of resistance at the time and to the consequences it entailed (eg continuous increase in the quantities of insecticides used), irrespective of how much attention was drawn to it in instructions and lectures: SPECIAL PART B) and C).

We began to tread new paths in pest control, parallel to the research in hand with chemical agents, presented in PROJ VI-XIII (2), but the time was not ripe for this: the “environmental awareness was not developed enough” as we would say today: SPECIAL PART C).

The systematic search (5, 7) for new potent “halo compounds with new spatial distribution of halogenates” under the heading of “halocarbon-based contact insecticides” [(410) in (2)] led the author to the DIENE group insecticides - and one of them, M 410, was considerably more potent than DDT (7, 8, 2).

Despite this success, the author – on the basis of discussions with older, more experienced colleagues (Pl 1) – from the beginning did not underestimate the problems entailed in controlling pests with not naturally available chemical agents and, as mentioned above, sought other, less toxic possibilities of pest control.

The leading scientists of the institutions named (Pl 1, col 1 and 2) made their widely differing views on CHEMICAL PEST CONTROL known to the author. It is true that they supported him sufficiently, but they were not sparing in their criticism and so influenced, as is detailed in Pl 1, the author’s attitude and – without saying so explicitly – postulated ways that favoured LESS CHEMICAL PEST CONTROL: SPECIAL PART D).

This section – with its criticism of synthetic insecticides – should not, however, conclude without laying special emphasis on the significance and necessity of chemical pest control, best done by quoting some statements from competent scientists as mentioned in the introduction to this essay.

When human lives are at issue as in the case of malaria, or if people can be saved from starvation and there is no other solution (yet), we should be willing to compromise regarding the use of chemicals. (Wenn es um Menschenleben geht, wie im Falle Malaria, oder wenn man Menschen vor dem Hungertod bewahren kann und es (noch) keine andere Lösung gibt, sollte man hinsichtlich Einsatz von Chemie zu Kompromissen bereit sein).

Plate 1: List of author’s workplaces from Sept 44 to 1948, ordered by “leading scientists”, “scientific institution”, “view on CHEMICAL PEST CONTROL” (2)

Scientist

Scientific institution / period employed

Viewpoint on CHEMICAL PEST CONTROL (direction: LESS CHEMICAL PEST CONTROL)

Prof Dr H Schloßberger,

institute director,

serving general

Institute of Hygiene, University of Jena (faculty of medicine),

Oct 44 - Mar 45

Critical of widespread, purely chemical pest control as practised by Allies and German forces in WW2. Already knew in Oct 44 about Allied use of DDT in Naples (typhus) via Military Intelligence. But aided author’s investigations.

Prof. Dr. H. Keller,

inst dir and head of office

Inst of Pharmaceutics, Univ of Jena and Foodstuff Inspection Office,

Sept 45 - end 1946

For using chemical agents in pest control, but warned against widespread use due to expected consequences for food chain: pests – birds/mammals – humans. Put private lab at author’s disposal (funded by author)*

Prof. Dr. Harms,

inst dir

Prof. Dr. Pflugfelder,

head of department

Inst of Zoology, Univ of Jena (faculty of mathematics and natural sciences),

Dec 45 – end 1946

Prof.Harms, critical of chemical pest control, but approved author collaborating with Prof. Pflugfelder. In first talks Prof. Harms drawled: “Young man, we’ve got enough delousing agents.**

Pflugfelder’s collaboration aided systematic testing of 400+ compounds for insecticidal activity

Prof. Dr. Dr. K. Lohmann,

inst dir

Inst of Physiological Chemistry, Univ of Berlin (faculty of med),

from 1947

Principal reviewer of my thesis to qualify as professor, written elsewhere. Acknowledged need to seek new insecticidal agents, particularly as resistance already reported 1948 after intensive DDT use***

Prof. Dr. A. Hase,

inst dir

German Inst of Biology,

Berlin-Dahlem

from 1947

Positive about chemical pest control, gave author (after leaving Jena) critical advice in Berlin. Joint experiments with bugs (focus of H’s work) able to crawl for hours on pure DDT crystals without being poisoned: insecticides in crude or oily state more potent than purest compounds (535) and VIII 3.3 in (2)

* Working on own account, not as university member (reason: danger of “deportation of qualified personnel to Soviet Union”)

** In rheinländlischer Mundart sagte Professor Harms: „Junger Mann, Entlausunchsmiddel hammer doch jenooch“

*** Prof. Lohmann let the istitute practically all to the author including a staff of more than 10 because he himself did not do any more research

SPECIAL PART

A) The Carson Case

B) Resistance experiments

C) “Chemical cudgel” and “environmental awareness”

D) Other ways of controlling pests: less chemical pest control –

various options

E) Deduction of the term “Biological Chemistry”, including Xenobiotica

F) Toxicological Data for humans and mammals

A) The Carson Case

In Nov 1949 Ms Rachel Carson turned the first time to the author for advice and requested his books entitled “Kontakt-Insektizide auf Halogenkohlenwasserstoffbasis I and II” (5,6) and for further material regarding alternatives, especially regarding lecture manuscripts.

Below is a list of all documents sent by the author to Ms. Carson in 1949 and, at her request, again in 1952 (witnesses: E. Schölzel, H.J. Hein, cand. chem. and Nussa-Schuster, cand. pharm.). None of the publications cited below were ever quoted by Ms. Carson in her book (3). Therefore, it seems all the more important to the author to show how critically and conscientiously experts dealt with synthetic insecticides at the time and what had been published before Ms. Carson wrote her treatise.

The secretary of the Physiolog chem Inst, Humboldt University Berlin, Elisabeth Schölzel, sent in the author’s name in Dec 1949 as registered mail the following documents:

- 2 books (5,6),

- 2 Mitt Physiolog-chem Inst Berlin R 11 and R 12 (7,8)

- Mss of the lectures, entitled “Kontakt-Insektizide der DDT, HCH, DIEN-Gruppe“ (part I) together with “Kritische Anmerkungen zum Thema der chemischen Schädlings-Bekämpfung und Alternativen“ (part II), given from the author on 29 Jan 1948 in BUNA, Schkopau (9), on 11 Febr 1948 in LEUNA, Merseburg (10), and on 14 Mar 1948 im Werk KAUSTIK, Wolfen (11).

There was a break between the parts I and II of each lecture. The break was used to bring to an end the experiment, begun 15 mins after the start of the lecture and shown by epidiascope, to poison Oriental cockroaches Blatta orientalis with M 410. The glass test containers were surrounded by deep flowing water to protect the test insects from the heat of the projector lamp [ie so as not to kill them by heat instead of M 410]. As the toxins like M 410 that are used in low concentration act relatively slowly, the effect was clearly visible only after 45 mins.; cf also comment in ref (10).

Mrs Carson was informed about the lectures mentioned below (11-13) through Prof F Herter, Zoology FU, who participated on the “Thuesdays 5 o’clock tea meetings” in the Inst of Mathematics FU of 16 Nov 1950 (11), 22 Febr 1951 (12), and Mar 1951 (13).

Answering the second letter of Ms Carson she received 1952 also per registered mail from the author:

- Mss of the 3 lectures, entitled:

“Schädlingsbekämpfung unter Einschränkung chemischer Gifte“ held on 16 Nov 1950 (11), continued on 22 Feb 1951 (12) and on 1 Mar 1951 regarding also natural occurring products (13)

- The book “Kontakt-Insektizide auf Halogenkohlenwasserstoff-basis III” (14);

- REPORTS zu (6): - Chem. Zbl. C 1949 II, 1226; – Anz. Schädlings-kunde 23, 62 – 63 (1950; - Z.Pflanzenkrankh. (Pflanzenpathol.) Pflanzenschutz 1950, 153 – 155; - Gazz. Chim. Ital., 80, VI-VII (1950); - Dtsch. Apother-Ztg. 1950, 188; - Dtsch.Ges.Wesen 5, 313 – 314 (1950); - Z. Naturforschg. 1950, 290 – 291; - Pharmaz. Zentralhalle Dtschl. 1950, 362; - Pharmazie 5, 190 (1950); Angew. Chem. 62, 441 (1950); - Z.Pflanzenbau u. Pflanzenschutz 1 (45), H. 2, 95 – 96 (1950); - Z.hyg.Zool. 38, 184 – 185 (1950); - Chem.Age 1951, 145 und 1950, 724; - The Royal Horticultural Society, London 1950, Nov. ; - Le génie civil 70, 297 (1950); - Botyu-Kagaku, Kyoto 1950, Heft 1 [Prof. Dr. S. Takei]

The author also sent Ms Carson outdated documents with appropriate annotation in which R WIESMANN from the Wädenswiler Research Institute, Switzerland (later Department of Biology at GEIGY Werke) referred to the “harmlessness of GESAROL for bees”, eg that “GESAROL is only toxic if it is sprayed or dusted directly onto bees” [WIESMANN’s 1942 statements, cited at (485b) in (2)], very soon refuted by American work and also by the author.

Own actions and experiences concerning D)

to 1:

E F Knipling had already postulated in the 30s that it was best “if one would leave insects to control themselves”, eg by making it impossible for them to procreate: consideration of sexual sterilization or the use of synthetic or natural sterilizing agents.

Concerning this subject the author made "Critical remarks about SEXUAL STERILISATION OF INSECTS BY IRRADIATION" and "CHEMICAL STERILISATION" in 2 lectures given in English due to presence of 12 American and British scientists in colloquium of RIEDEL DE Haen Co, Berlin-Britz in Oct 52, chair director Dr A Heymons (18)

The content: The irradiation technique requires mass release of sterilized male insects and special, expensive equipment to irradiate and transport them (more effective in pupal stage) as well as airplanes to distribute them. High irridation doses required for sterilisation may kill many insects. Consequences from these reports: The chemical sterilisation of insects seems to be more practical and less expensive (chemosterilants, mitose poisons). [Lectures not published as no own experimental data (bibliographic research)]

to 2:

Instead of using direct-action toxins, use of compounds that are structurally similar to those found naturally and after incorporation in the organism disrupt or destroy the intermediary metabolism, eg peptides (L)_x–D–( (L)_x[x = 1,2 etc, channelling in of D-amino acids], amino acid homologues or altered nucleic acid bases, the latter to be considered as the sexual sterilizers: Plate 2 concerning the “attemps to negatively influence the metabolism of insects by placement of unphysiological compounds (in their food) structurally similar to those occurring naturally” (19a-e).

Plate 3:

Unphysiological compounds and compound types that have been tested for effect on metabolic processes in insects. Experiments with I on Drosophila melanogaster M. and also on microorganisms led to interesting results.

Phenylalanine derivatives like eg N-(x-methylmercaptobenzoyl)-substituted ones and their oxidation products and flourinated phenylglycine peptides
Uracil and xanthine derivatives and others based on pyrimidine and purine
Glutamic and aspartic acid derivatives, eg thalidomides
Carrier oligopeptides with D-amino acids in intermediate position, eg L-lysyl-D-tryptophanyl-L-phenylalanine and 61 others
Pyrimidine and dicarboxylic acid derivatives containing F, eg fluor orotic acid, difluoromalic acid diethylester
Nicotinyl ammine acid esters and nucleoside derivatives
151 preparations 1976-85

Literature:
12 cites 1948 to 1985 (2) in
R Riemschneider: Rereading 66 years of chemistry “Nachlese – 66 Jahre Chemie”, there under Project XXI.

Plate 3 taken from:

http://www.bwwsociety.org/journal/html/thalidomide.htm

More information concerning this subject in Plate 4 (next page).
Plate 4:

Research report from Faculty of Chemistry, R Riemschneider, Free Univ of Berlin 1978, p 288 (19e)

Concerning „isolysine“ see (27).

Translation of Plate 4:

Influencing metabolic processes by means of unphysiological compounds ("environmentally friendly insecticides")

For a number of years, experiments have been carried out in our laboratories to develop substances for pest control that interfere with the metabolism and / or succession of generations of insects, without however the toxic and other side-effects of the more common insecticides. Our aim is thus not insecticides in the proper sense, but rather compounds that are absorbed by insect metabolisms as substitutes for physiologically active compounds due to their constitutional similarity and impair procreation or other functions of the organism. Applying them could represent an "evironmentally friendly" method of control. To these compounds which effect the metabolism we count eg a) p-X-substituted phenylanan-ines (X = F, CH₃) that are incorporated into the body's own proteins and / or destroy enzymes b) unphysiological acids of the citric-acid cycle, like fluoromalic acid, that can block enzymes, further c) modified bases like eg haloorotic acid, S-alkyl-thio-fluororotic acid ester. The choice of unphysiological compounds to interfere with the metabolism, can generally be made from the following points of view: they must be constitutionally similar to the naturally occurring, physiologically active compounds and not deviate too much with respect to molecular weight and size of molecule. A certain competition between the unphysiologically and physiologically active substances plays a part, eg in that the latter can be displaced during the formation of an inactive molecule or incorporation in a nucleic acid chain or in a larger protein molecule. Halogen-free compounds, eg CH₃ derivatives are preferable as they themselves, and their degradation products too, are not expected to be toxic, eg methylated glutamic acid, homolysine and isolysine (27).

Substances that act as enzyme toxins or inhibitors on the enzymes of the insects own bodies, but have no effect on the enzymes of warm-blooded animals are to be mentioned in this context. The relationship between the quantities of metabolism inhibitor and foodstuff also needs to be taken into consideration. The small amount of inhibitor taken in with the food that is injurious for an insect body will in general cause no damage to a larger warm-blooded organism.

to 3:

neem tree: (13, 20a-c)

Recalling the insecticidal action of active agents from the neem tree, that are harmless for humans when applied wisely. Vegetal preparations from the seeds and leaves of the neem tree that have been used for pest control and many other purposes for centuries in India, Brazil and neighbouring countries seemed particularly interesting as they are non-toxic for humans and animals – if applied externally:

The systematic application of the active neem tree agents in the soil can protect plants against pests (Pflugfelder, Riemschneider, Jena, from 1946).

The author was able to obtain a continuous supply of neem tree seeds, leaves and bark from the Patel and Azhar families from 1947 [arranged by Prof Dr Butanandt, who wrote his dissertation about rotenone in Göttingen and was very interested in the author working on the chemistry and applications of active substances from the neem tree] and also from Prof R Wasicky of São Paulo, Brazil from 1949. Mahmud, the scion of the Azhar family, later worked (1971-90) in the Institute of Biochemistry headed by the author at the Free University of Berlin.

Neem tree leaves have a pleasant smell, unlike the seeds (which is of interest for cosmetics according to own experiences). We placed neem tree leaves under legumes and cereals to protect them in storage. Neem tree bark has antiseptic properties and is probably unsuited for pest control (It is used for dental care in Asia). Neem tree seeds are harvested when they are yellowy-green and immediately dried, then stored in thin layers in a ventilated place, protected from sun and rain. The dried seeds are milled for use in pest control.

On the subject of the neem tree’s repellent factors for chewing insects: We will refrain from detailing our extensive experiments over several years (1970-75) to isolate a pure Azadirachta repellent factor for chewing insects (20c): Pure C₃₂H₄₀O₁₁, known as Azadirachtanine, from mp 225-226°C is described. Our purest preparation isolated had the empirical formula C_28-30H_35-42O_9-12, mp 223-225°C (20c). The Tetrahedron Letter 26 6435, 1985 confirms our results (20c) progressing in an excellent way.

Here thanks once again to Ms M Fereira, Mr W Pollack as well as Dipl-Chems H-J Hein, M M Souza and M Azhar for their untiring work in this project too.

olive oil: residues from olive oil production (21):

Our experimental results are still secreted by industry`s request: In 1994, we resumed our experiments from 1948-58, external funding.

To 4:

Malaria control by killing plasmodium according to new method (22):

It was well known that anopheles prefer nectar- and sugar-containing sources to satisfy their energy requirements rather than human blood; according to measurements, the ratio is approx. (10 - 15) : (1). This habit could be exploited by providing bait through covering synthetic plants such as flowers with foils containing sugar with toxins acting against plasmodia. The pathogens absorbed would be killed after the mosquitoes have ingested the active substance. Preliminary experiments have shown that it is possible to use foil material which is impossible to penetrate for other insects; cf. PROJ XVIII: Permeation experiments (secreted).

Mosquitoes free of plasmodia no longer cause damage when they sting.

to 5:

Use of scent attractants and oviposition lures (23a-e)

to 6:

Pest control with molasses/sugar, molasses residues plus phosphoric acid - Own experience and experiments 1951-60 [secreted (24)]:

Results: Spraying molasse solutions with addition of Coca-Cola, later for larger experiments with H₃PO₄, helped to grow an ant population which then eliminated the crop. Repetition experiments confirmed the results.

to 7:

The number of malaria deaths is rising again worldwide.

Deciphering the Anopheles mosquitoes’ DNA code in 2002 has brought no medical progress to date.

Treatment of malaria is at present largely based on the drug Artemisinin, isolated from the annual mugwort (Beifuß) [Artemesia annua: active ingredient in traditional Chinese medicine for 1500 years; today produced in China under the name “Kuratim” in co-operation with a Swiss company].

A factory was built in Narobi in 2004 with aid from China’s government and help from Chinese scientists to produce the microorganism BTI for controlling Anopheles larvae. As is known, a toxin produced by BTI kills the larvae but not the mosquitoes. One problem in controlling malaria with BTI is using it at the right strength, that must be determined in preliminary field tests.

Further details and other endeavours to solve the malaria problems cannot be taken into consideration here because it would be beyond the scope of this frame.

E) Deduction of the term “Biological Chemistry“ – including Xenobiotica

In an interview given on January 23, 1968, to the Berlin broadcasting station RIAS for the programme "Unser wissenschaftliches Tagebuch", the author explained the significance of the subject BIOCHEMISTRY, better BIOLOGICAL CHEMISTRY and its delimitation against other subjects: Pl 5.

cf. http://www.bwwsociety.org/journal/html/persons.htm

„Unter Biochemie – besser Biologische Chemie – verstehen wir die Lehre der stofflichen Veränderungen in der belebten Natur.

Beispiele: Photosynthese, alkoholische Gärungen, Biosynthese der Eiweißkörper und andere, d.h. beim Studium der Biochemie erfahren wir, wie das Leben chemisch vor sich geht. Wir ermitteln die Bestandteile von tierischen und pflanzlichen Organismen, wir beschäftigen uns mit der Frage, wie diese Bestandteile gebildet werden, wie abgebaut werden, welche Funktionen sie tragen, wir betrachten ferner das Zusammenspiel dieser Stoffe im intermediären Stoffwechsel.

Der Biochemiker studiert aber auch die Beeinflussung von Stoffwechselreaktionen durch natürliche und durch Fremdstoffe (Xenobiotika).“

Plate 5:

This scheme was developed by the author in 1952 after a discussion with Prof. Dr. Richard Kuhn. It makes the subject "Biological Chemistry" (called "Biochemistry" for a long time) equivalent to the recognised subjects "Inorganic", "Organic", "Physical" and "Technical Chemistry". It also forms the basis for the interview recorded by reporter Friedrich Marsfeld at the Berlin broadcasting station RIAS on January 23, 1968, for the programme "Unser wissenschaftliches Tagebuch" (Our scientific diary). See the text of the RIAS interview.

F) Toxicological data for humans and mammals

concerning DDT and analogues are given 1949 in the author’s monography (6) : Reports about effects on skin (DDT, dissolved and not dissolved), on eyes, on respiration system, on digestive system (acut, chronically; self-trials, accidents). - Estimated DL₅₀ man for DDT: 150-600mg pro kg (28). Amongst other things the author explained: The relative nontoxicity of DDT-preparations for mammals is very much depending on its rather negligible - resorption impeding - water solubility; therefore it would be difficult to commit suicide with DDT powder, except DDT is taken in organic solvents which are mostly more dangerous than DDT itself.

The accumulation of DDT in fat tissues in ppm quantities, caused by uptake through food chain, creates problems: Enrichment of DDT in fat tissue; but its concentration is reduced in the course of time. We should keep in mind

- that in the human organism all atoms of the endogenous compounds are completly replaced after and within seven years – stated through isotopic method

- that the decomposition of the xenobiotics DDT (DDD) in the body goes via HCl splitting to “urine capable” dichlorodiphenyl acetic acid.

Today we know that a suitable way of application and a well calculated dosage of synthetic insecticides - directed by specialists – is helpful to avoid health damages.

Closing words:

Durch den konsequenten Einsatz von DDT (bzw.DDD), d.h. durch die direkte Vernichtung der die Malaria übertragenden Insekten war diese Krankheit in den 50er Jahren praktisch ausgerottet worden. Dank solcher Veröffentlichungen wie „Silent Spring“ und auf Grund übertriebener Aktionen der „Grünen“ sind in manchen Ländern die synthetischen Insektizide immer mehr in Verruf geraten, es kam sogar zum 100%igen DDT-Verbot; dies hat erneut zum Ausbruch der Malaria geführt - mit der Folge von Millionen Opfern (von mehr als 40 000 000 in den Jahren 1969 bis heute).

Man wird fragen dürfen, ob es gerechtfertigt war, angesichts solcher Zahlen von Malaria-Opfern – und darunter Millionen von Toten – ein völliges DDT-Verbot auszusprechen und aufrechtzuerhalten. Ob diejenigen noch ruhig schlafen können, die das zu verantworten haben?

Verfasser hatte in seinen Publikationen und Vorträgen immer wieder „recommended a middle course under the premise and target: Less Chemical Pest Control – looking for other ways for controlling pests” (9-13, 1).

ADDENDUM:
In a German Newpaper from April 2000 the author found the following notice: On April 25th, in Abuja, Nigeria, the number of 44 statesmen and government chiefs signed a declaration to fight against further spreading of malaria. This day should be remembered every year as AFRIKA-MALARIA-DAY. In the preceeding discussions the chiefs stated: "Between one and three millions of people are dying every year of malaria, 90% of which in Africa.“

BIBLIOGRAPHY

(1) R.Riemschneider,

Chlorine chemistry for pest control research, The BWW

Society / The Institute for the Advances of Positive Global Solutions July/August 2005, http://www.bwwsociety.org/journal/html/pestcontrol.htm

(2) R.Riemschneider,

“Re-reading – 66 years chemistry” (in preparation)

(3) Rachel Carson

“Silent spring” Houghton Mifflin Comp. Boston, 1962

Zur 4. Auflage aus dem Jahre 2007 gibt es ein Vorwort von Dr.Joachim Radkau. Riemschneider setzt voraus, daß jener keine Kenntnis davon hatte, daß Verfasser seinerzeit umfangreiche deutsch-sprachige Informationen, und zwar in den Jahren 1949 bis 1952 der Autorin zur Verfügung gestellt hat (SPECIAL PART A).- Obwohl es inzwischen ein Czernobyl gegeben hat, lobt Radkau ,dass die Autorin in „literarischer Form des SILENT SPRING“ die damals durch Atomwaffenversuche hervorgerufenen Ängste auf die mit Pestiziden verknüpften Risiken übertragen hat. Welch ein Irrtum, derartige Zusammenhänge zu konstruieren! Atomunfälle von der Art Czernobyl enden praktisch nie - in Anbetracht der hohen Halbwertszeiten von radioaktiven Materialien und wenn man bedenkt, wie kurz ein Menschenleben ist.

http://www.bwwsociety.org/journal/html/alternatives.htm

(4) cited in lecture:

R Riemschneider

“Halocarbon-based contact insecticides I”, (Kontakt-Insektizide auf Halogen-kohlenwasserstoffbasis, Mitt I)

Lecture given in chemical colloquium of Friedrich Wilhelm University of Berlin on 28 Feb 47, published in “Die Pharmazie” 1947, pp 77-99 (5)

(5) R. Riemschneider

Zur Kenntnis der Kontakt-Insektizide I

Published in 2^nd special issue, 1^st supplementary vol of journal “Die Pharmazie” 1947, pp 77-179, title: On the knowledge of contact insecticides 1

Hinweis auf einige Referate und Buchbesprechungen der ersten bzw. zweiten Auflage des 2. Beiheftes (The spezial issue (all together 102 pages) has been printed 4 times):

- Chem. Zentralblatt 1947 I, 1235, 1404

- Medizin. Monatsschrift Nr. 7, Jahrg. 2, S. 262 (1947) [Dr. Schenk, München]

- Dtsch. Tierärztliche Wochenschrift 54, Jahrg. Nr. 39, Okt. 1947 - Desinfektion u. Schädlingsbekämpfung B, Heft 6 (1947) [E. Döhring]

- Süddeutsche Apotheker-Zeitung 87, Nr. 11 (1947)

- Thüringer Volk Nr. 106 vom 1.7.1947

- Kosmos 1947, 268; - Pharmazeut. Zentralhalle Dtschl. 86, 255 (1947)

- The Chemical Age 1948 (24.7.), Nr. 1515, S. 132

- Gazetta Chimica Italiana 27, XII (1947); - Tagesspiegel 2.7.1947

- Anz. Schädlingskunde 21 30 – 31 (1948) [W. Ext, Kiel]

- Anz. Schädlingskunde 22, 144 (1949) [Frickinger]

- Dtsch. Gesundheitswesen 3, 570 (1948)

- Pharmazie 4, 94 – 95 (1949) – 2. Aufl. (unverändert)

- Chem. Zbl. 1950, I, 1651 – 1653; - Chemiker-Ztg. 74, 573 (1950)

- Angew. Chem. 61, 427 (1949) [Boschke]

- Arzt u. Patient 63, 34 – 35 (1950)

(6) R Riemschneider

Halocarbon-based contact insecticides II ( Kontakt-Insektizide auf Halogenkohlenwasserstoffbasis II)

published in special issue 9, supplementary vol 1, “Die Pharmazie 1949, pp 649-800, title: “On knowledge of contact insecticides II” (Zur Kenntnis der Kontakt-Insektizide II) - Bull III (14)

(7) R.Riemschneider, A.Kühnl

Chemistry of polyhalocyclopentadienes and related compounds,

Bull.I (Zur Chemie von Polyhalocaclopentadienen und verwandten Verbindungen)

Mitt. Physiolog.-chem. Inst Berlin R 11, 8p, Oct 1947, ref. in Chem. Abstr. 49, 8216; 48, 2973. This paper was later, published for a second time, in: Monatsh.Chem. 86, 879-886 (1955). Extensive details to this topic in PROJ XI, ref. (697) in (2).This paper corresponds to [(434b) in 2]

(8) R Riemschneider

M 410 as contact insecticide of halocarbon class (M 410 als Kontakt-Insektizid der Halogenkohlenwasserstoffklasse)

Mitt Physiolog-chem Inst, Berlin R 12, 11 p, Dec 47 [150 copies, hectographed] - in Jan 48 sent to Patent Dept, Farbwerke HOECHST AG, Frankfurt-am-Main by REGISTERED letter together with a copy of Bull R 11 from Physiolog-chem Inst Berlin of Oct 47 (434a) -

Detailed review in „Pflanzenkrankheiten (Pflanzenpathologie) Pflanzenschutz“ 56 366 (1949); also in Seifen, Fette, Öle, Wachse 74 80 (1948); Natur und Technik 3 n^o 19, 182 (1949) Chemical Abstracts USDA 1949, 46011; Orion 12, 470 (1949); cf. (1).

Several lectures on CHEMICAL PEST CONTROL RESEARCH (9-13)

(9) R Riemschneider

Two-part lecture given in chemical colloquium of BUNA-Werke, Schkopau on 29 Jan 48,

Part 1: “Contact insecticides of DDT, HCH, DIENE groups” (Kontakt-Insektizide der DDT-, HCH-, DIEN- Gruppe)

Part 2: “Critical comments on chemical pest control and alternatives” (Kritische Anmerkungen zum Thema der Chemischen Schädlingsbekämpfung und Alternativen)

Abridged versions: Part 1 in Pharma Zentralhalle 87, 132-134 (1949), review C 1949 II, 1226 (Verlag Chemie);

Part 2 in Mitt Physiolog-chem Inst Berlin, Jan 48, 8 p

(10) R Riemschneider

Two-part lecture given in chemical colloquium of LEUNA, Merseburg on 11 Feb 48 and of Werk KAUSTIK, Wolfen on 14 Mar 48,

mss 1948, 14 p

Part 1: “On halocarbon class contact insecticides and phosphorous-bearing ones, particularly so-called ‘hexaethyl-tetraphosphate’ (HETP)

Part 2: “Criticism of extensive pest control with chemical toxicants and alternatives”

Published in Pharmaz 4 291 (1949); cf (2) there VI 5, Tab 13/14

The author split the lectures at the BUNA (9), LEUNA (10) and KAUSTIK (10) works into two parts at the wish of their respective managements, who wanted not only the latest information on CHEMICAL PEST CONTROL RESEARCH but also critical comment on the subject.

Chief engineer Richter from the LEUNA works had confidentially informed the author that LEUNA and BUNA were at the time were confronted with the decision as to whether they should get involved the field of chlorine chemistry or not – tending more towards “no”.

Author had known chief engineer Richter since 1943 as former head of mechanical engineering department at RUHRÖL GmbH, cf PROJ III in (2).

(11) R Riemschneider

Lecture I: “Controlling pests with chemical agents – consequences for humans, animals and plants - interference of insecticides and follow-up products in the food chain – stability problems” (Bekämpfung von Schädlingen mit chemischen Mitteln --- Folgen für Mensch, Tier und Pflanzen --- Eingriff von Insektiziden bzw. Folgeprodukten in die Nahrungskette --- Resistenz-Probleme)

Lecture given on 16 Nov 50 in round-table talks during afternoon tea that used to be at 5 o’clock on Thursdays during term in Inst. of Mathematics at Free University of Berlin. Invitation and chair: Prof Dr A Dinghas, institute director. Profs present:

Dr M Fischer (Physiolog chem)

Dr F Herter (zoology)

Dr W Heubner (pharmacology)

Dr Jakobson (mathematics, visiting prof from Norway)

Dr W Lautsch (organic chemistry)

Dr F Richter (geology)

Dr G Schenck (pharmaceutical chemistry)

Dr F Scherer (crop protection dept, HOECHST – by special invitation)

Dr Ivan Stranky (physical chemistry)

Ms Oct 50, 32 p (unpublished)

Ms Nov 50, 11 p (unpublished)

(12) R Riemschneider

Lecture II: “Pest control limiting chemical toxicants” (Schädlingsbekämpfung unter Einschränkung chemischer Gifte)

given on 22 Feb 51 as continuation of lecture I (11), also in Inst of Maths at Free Univ, chair: Prof Dr A Dinghas

Lectures I and II were repeated on 06 and 07 June 51 in colloquiums at Plant Protection Dept of HOECHST at the instigation of Dr F Scherer (director) and the invitation of HOECHST’s management.

Ms Jan 51, 30 p (unpublished)

Publication of the contents of the lecture was deferred so that the scientists from the Plant Protection Dept could check the proposals made and had enough time to study the literature. For the first time, there was talk of a “chemical cudgel” in the discussions, but also that it should not be talked about too much.

Products of the neem tree, to which half of the 01 Mar 51 lecture was devoted, were dealt with in detail; cf also (20a-c) and (13)

(13) R Riemschneider

Lecture III [given on 01 Mar 51, similar to previous (11, 12)]

“Pest control limiting synthetic chemical toxicants: insecticidal activity of naturally occurring vegetal products like pyrethrum, rotenone, but above all products of neem tree. Fungicidal activity of olive oil production residues” (Schädlingsbekämpfung unter Einschränkung synthetischer chemischer Gifte: Insektizide Wirkung natürlich vor kommender pflanzlicher Produkte wie Pyrethrum, Rotenon, vor allem aber Produkte des Niem-Baumes. Fungizide Wirkung von Olivenölproduktions-Rückständen)

Ms Mar 51, 25 p (unpublished)

Neem tree: For centuries the Indians have venerated the neem tree as the “donor of health” that protects people from plant and stored food pests as well as disease carriers. Valuable products can be manufactured from both seeds (→ oil) and leaves (→ aqueous and alcoholic extracts) that according to India’s experience can be used as – for humans non-toxic – insecticides and repellents.

Olive oil: Extracts from the large quantities of residues obtaining from the production of olive oil showed considerable fungicidal and some insecticidal activity. Plant parts to be protected against fungicides are sprayed with extracts from olive oil production residues (aqueous, diluted, alcoholized) The Plant Protection Dept at HOECHST did not, however, wish to pursue this avenue. - The author did so in his work 1948-58.

(14) R Riemschneider

Bull III: Halocarbon-based contact insecticides: On the further development of hydrogen chloride class insecticides (Kontakt-Insektizide auf Halogenkohlenwasserstoffbasis: Zur Weiterentwicklung der Insektizide der Chlorwasser-stoffklasse)

Euclides 11 373-381 (1951) Euclides 12 35-41, 91-105 (1952), also published as independent paper (book)

(15) U. Kulke

Newspaper „Die Welt“ from Nov 7, 2007, p 31.

(16a) R Riemschneider, B Rohrmann

On breeding DFDT-resistant Drosophila (Über die Zucht DFDT-resistenter Drosophila)

Anz Schädlingskunde 23, 148 - 149 (1950); details in SPECIAL PART VIII 3.4

Breeding of the strain was continued in the Crop Protection Department of the MONTECATINI Works, Via Turati, Milan from 1951, as well as in the labs of BOMBRINI, PARODI, DELFINO Company, Rome. The valuable fly material was then handed over during my stay in Milan and Rome in April 1951 for further research.

(16b) R Riemschneider, R Scheffler, B Rohrmann, H-J Hein, G Bode

On breeding M 410-resistant Drosophila

Mitt Physiolog chem Inst Berlin, Jan 50, 9 p (100 copies hectographed and distributed)

As with DFDT (16a), the experiments with M 410 were begun at the end of 1947 to demonstrate the need to reckon with resistance and draw attention to coming problems and solution (17-23).

(17) R Riemschneider

“Halocarbon-based contact insecticides: On the chemistry of DIENE group insecticides – structure and configuration of adducts from hexachlorocyclopentadiene and unsaturated compounds as well as the follow-up products” (Zur Chemie der Insektizide der DIEN-Gruppe –Konstitution und Konfiguration der Addukte aus Hexachlorcyclopentadien und ungesättigten Verbindungen sowie deren Folgeprodukte.)

Lecture, given in May 1974 in colloquium in building IV of Central Inst of Biochemistry and Biophysics at Free Univ of Berlin.

In the discussion, the author drew attention to his lectures of 29 Jan 48 (8), 11 Feb 48 (9), 16 Nov 50 (11) and 23 Feb 51 (12) on “Controlling pests with chemical agents – consequences for humans, animals and plants – influence of insecticides and daughter products in the food chain – resistance problems” and “Pest control limiting chemical toxicants” and distributed hectographed summaries of the lectures: (9-13). The summaries of the previous lectures had been prepared as the lecturer had reckoned with “attacks” by the Greens. The list of the scientists attending, named at (11), was then also handed out so that it was possible to request more detailed information, also the special editions of the lecture “Dangers and precautions when using modern insecticides”, given by the author in Jan 48 [extracts reproduced in “Arzt und Patient” 63 n^o 3 (1950), 2 p].

At the end of the long discussions, the author pointed out that he had sent copies of his 1948-51 lectures presented here to Rachel Carson, the nature protection writer, years before her book “Silent Spring” was published - in this context, compare the author’s comments about Ms Carson in SPECIAL PART A).

The author recommended several times not to ban DDT and DDD completely to avoid new malaria deaths; he also recommended a middle course under the premise and target “less chemical pest control”.

(18) R. Riemschneider

"Critical remarks about SEXUAL STERILISATION OF INSECTS BY IRRADIATION" and "CHEMICAL STERILISATION"

in 2 lectures given in English due to presence of 12 American and British scientists in colloquium of RIEDEL DE Haen Co, Berlin-Britz in Oct 52, chair director Dr A Heymons

Methods of LESS CHEMICAL PEST CONTROL (19a) – (24)

(19a) R Riemschneider

Lecture: "Possibilities for negatively influencing metabolic processes in insects by means of compounds that are similar to naturally occurring ones" („Möglichkeiten der negativen Beeinflussung von Stoffwechselvorgängen in Insekten durch Verbindungen, die natürlich Vorkommenden nahe stehen.“)

Lecture given in colloquium of Inst of Physiolog Chem Berlin, in Dec 48 (invited: managers of RIEDEL de HAEN Co and Profs Drs Zacher and Hase, Berlin-Dahlem)

Ms Nov 47, 18 p

Lecture given again in internal colloquium at Farbwerke HOECHST in Jan 50. Ms secreted till 1970 at the request of the company's management.

The 1948 - 86 bulletins on the subject dealt with here are quoted at [(1176 a - n) in (2)] - more on the subject: (19c and Plate 4).

(19b) R Riemschneider, O Göring, E Frömming, K Hauptmann

Interfering with the metabolic processes by means of 65 unphysiological compounds: test animal Drosophila melanogaster MEIGEN (Zur Beeinflussung von Stoffwechselvorgängen durch unphysiologische Verbindungen: Testtier Drosophila melanogaster MEIGEN.)

Test reports 1948, 31 p

(19c) R Riemschneider

"Alternatives to pest control with chemical toxins (LESS PEST CONTROL RESEARCH): Influencing metabolic processes by means of unphysiological compounds" („Alternativen zur Schädlingsbekämpfung mit chemischen Giften (LESS-PEST CONTROL RESEARCH): Zur Beeinflussung von Stoffwechselvorgängen durch unphysiologische Verbindungen“)

Lecture given in Jan 1951 in chemical colloquium of RIEDEL DE HAEN Co, Berlin-Britz (chair: director Dr A Heymons).

cf http://www.bwwsociety.org/journal/html/thalidomide.htm , 2004 and PROJ XXI in (2).

(19d) R. Riemschneider, H. Pehlmann

Zur Beeinflussung von Stoffwechselvorgängen durch unphysiologische Verbindungen II: F-haltige Pyrimidin- und Dicarbonsäure-derivated, z.B. Difluoroxalessigsäurediethylester, Fluororotsäure und –ester, alkylierte Oxalessigsäurediethylester, Hal- und Alkylsubstituierte Säuren des Citronensäurecyclus u.a. Säuren

Z.Naturforschg.20 b, 540-543 (1965)

(19 e) R Riemschneider, H.Pehlmann

Zur Beeinflussung von Stoffwechselvorgängen durch unphy-siologische Berbindungen III: Nicotinylaminosäureester und Nucleosid-Derivate

Botyu-Kagaku Kyoto (Scientific Pest Control) 41, 99-106 (1976)

(19 f) R Riemschneider

"28 years of research in the field of: Influencing metabolic processes in insects by means of unphysiological compounds („28 Jahre Forschung auf dem Gebiet der Beeinflussung von Stoffwechsel-vorgängen in Insekten durch unphysiologische Verbindungen“)

Lecture given in colloquium of Central Inst of Chemistry, Fed Univ of Santa Maria (UFSM), Brazil in Aug 76

The most important results were patented by foreign industrial enterprises at the end of the 70s.

(19 g) Research report from Faculty of Chemistry, R Riemschneider, Free Univ of Berlin 1978, p 288: in SPECIAL PART D, report in Plate 4.

Some additional remarks with experimental data in PROJ XI 3.8; cf (2) 14 refs (1176a - 1176n)

(20a) R Riemschneider, M M Souza

Systemic use of aqueous neem extracts from neem seeds when watering or use of mixture of garden mould (100 parts) with residue from manufacture of neem expressed oil (3 parts) (Systemische Anwendung von wässrigen Niem-Extrakten aus Niem-Samen in Gießwasser oder auch Einsatz einer Mischung aus Gartenerde (100 Teile) mit dem Rückstand der Niem-Preßöl-Herstellung (3 Teile)

Ms 1978, 12 p (unpublished)

(20b) R Riemschneider, M Azhar

Progress in the area of neem tree research (1946-2001)

Synopsis 2001, 110 p (secreted); earlier reports (20a, c); cf SPECIAL PART VI 6.1 in (2).

(20c) R Riemschneider, H-J Hein, M Azhar, M Fereira, W Pollak

Pest control based on “Vegetal terpenes, continuing the research into neem tree products”

Results in SPECIAL PART VI 6.1 in (2).

9 lab reports 1970-75, 41 p (unpublished, secreted)

In many experiments conducted 1970-75, documented in the above lab reports, it proved possible to enrich the tripertene factor (repellent for chewing insects) from Azadirachta indica to a product with mp 223-225°C and mol wt 580-600, with the provisional empirical formula C_28-30H_35-42O_9-12 .

(21) R Riemschneider (lecturer), R Wasicky

“On the use of extracts in pest control, extracts that are isolated from the residues of olive oil production (from 1949)” (Über den Einsatz von Extrakten in der Schädlingsbekämpfung, Extrakten, die aus Rückständen der Olivenölproduktion gewonnen worden sind (ab 1949)

Ms Feb 58, 44 p in English and lecture of 1 Mar 58 in German

The fungicidal and insecticidal tests with the extracts from residues of olive oil production prepared in Berlin were carried out in Brazil, under the organizational direction of Prof Dr R Wasicky, University of São Paulo. The observed effects of the extracts were considerable and were to be corroborated by further tests. Unfortunately, HOECHST’s management and Plant Protection Department were not cooperative in this case. Prof Wasicky was very interested in advancing the PROJ, but his move to the University of Santa Maria, Rio Grande do Sul, kept him too busy.

The above mentioned olive oil residues used for extraction came from Italy through the good offices of Prof Dr Dino Marotta, Instituto di Santà, Rome: 1949-58

(22) R Riemschneider

“Über eine neue Methode der Bekämpfung der Malaria”

lecture, given end of August 1964 in English in colloquium of Univ. S. Maria, in Sala de Atos, Edificio sede da USM, S. Maria, RS, Brasil.

more details in PROJ XVIII in (2).

(23a) R Riemschneider (lecturer), H Vogt, T Nakazaki, W Gerischer,

F Pflugfelder

"Synthesis of unsaturated aliphatic alcohols and testing for attractant action (Pflugfelder, Stuttgart) - considering 'spatial structure and action' - photos of Stuart models" (Synthese ungesättigter aliphat. Alkohole und Prüfung auf Lockstoffwirkung (Pflugfelder, Stuttgart) – unter dem Aspekt «räuml. Bau und Wirkung»)

6 test reports 1956 - 61, 110 p, (unpublished)

2 lectures given in Agricultural College, Hohenheim, in Feb 57 and Mar 61.

(23b) R Riemschneider

Synthesis and activity of sexual scent attractants

Bull I: "Ways of pest control without use of chemical toxins"(Wege der Schädlingsbekämpfung ohne Anwendung chemischer Gifte)

Lecture given in colloquium of newly founded Inst of BIOCHEMISTRY, Free Univ of Berlin on 01 Sept 62 and repeated in colloquium of Chem Inst, Univ of Vienna. Includes results from [543 d, e in (2)].

(23c) R Riemschneider, A Kühnl, K Brockmeyer

Synthesis and activity of sexual scent attractants

Bull II: On synthesis of stereoisomeric alkyldiene-ols-(1) of

C-number 8 to 17 and their precursors

Lab reports 1962 - 63, 31 p, (unpublished)

(23d) R Riemschneider, G Kasang

Synthesis and activity of sexual scent attractants

Bull III: Stereoisomers of heptadecadiene-(10,12)-ols-(1)

Z Naturforschg 18b, 646 - 648 (1963)

(23e) R Riemschneider, G Kasang, C Böhme

Synthesis and activity of sexual scent attractants

Bull IV: 13-acetoxy-heptadecadiene-(8,10)-ol-(1), octadiene-(3,5)-ol-(1)-isomers and related compounds

Mh Chem 96, 1766 - 1780 (1965)

(24) R.Riemschneider (lecturer), R.Wasicky, F.R.,Pesserl, M.M.Faria, R. Souza

“A biological method for Pest Control on basis of so-called “Carbonhydrates/Ant”

Lectures given in Nov 1962 and Febr 1964 in the Pharmaceutical Institut, Univ S.Paulo (round-table-talks)

Lab and test reports 1962 and 1964 ,24 p

Experiments carried out in Brasil, organized from the Dept of Biochemistry FU Berlin in co-operation with Prof. Dr. R. Wasicky, Univ.S.Paulo, and Dr.Pesserl, Curitiba.

(25) R Riemschneider (lecturer), R Scheffler, B Rohrmann, H-J Hein,

G Bode

"Breeding M 410-resistant and the attempt to breed M 377-resistant Drosophila" („Über die Zucht M 410-resistenter und über den Versuch, M 377-resistente Drosphila zu züchten“)

Ms Dec 50, presented in conference room of RIEDEL DE HAEN Co, Berlin-Britz in Oct 50 - Method desribed in Plate 2 (16).

(26) R Riemschneider, A Kühnl

New halocarbon-class contact insecticides („Kontakt-Insektizide auf Halogenkohlenwasserstoffbasis“): M 410, M 377, M 344, M 414 ecc

Bull Physiolog Chem Inst, Univ of Berlin, R 8. Mar 47,

Review: Chem Zbl 1948 II, 344.

An abridged version of Bull R 8 was received as ms by the editors of journal Die Pharmazie on 15 Mar 47 but at the authors' request only published a year later in Die Pharmazie 3 115 - 116 (1948).

(27) R. Riemschneider, K. Brendel, K. Preuß

Synthese des Isolysins und Homologer

Mh.chem. 92, 1235 bis 1241 (1961)

(28) W.R. Hill, G. Robinson

A fatal case of DDT poison in a child

Brit. med. J. 2, 845-847, 1945

For correspondence: rriemschneider@yahoo.de