Tobacco is one of know plant based insecticide used to check insect pests in China and India.Sure,we can still use it and it has been recommended for in many crops.However the efficacy will not be comparable insecticide in terms of toxicity as well as persistence.

You also have to know exactly what is your purpose here, because considering the lethal doses/concentrations for both the target insect pest and surrounding animals and humans, legislation may require you tu use a lower dose than you planned to. Even if you are only at the experimental step now, these parameters are important, because further in the process, if your control strategy works and you want to register your method/product, you may have bad surprises. How about combining these products in a synergistic, integrated approach? 

I think, there is a risk of high rate of resistance development and cross-resistance, as for nicotinoids and neonicotinoids. So, are these alcaloids really eco friendly?

As mentioned in this string there are already commercially available insecticide formulations based on nicotine.

Again alluded to by others in this string, don't confuse natural with safe. There are many natural products that kill insect that are very very dangerous.

Sure, natural products do have a fit in pest control and add additional choice. They may be used in preference to synthetics for a multitude of reasons. However, more often than not, the synthetic alternative is safer with improved efficacy.

I think Franny Barsics is 100% correct by asking "what is your purpose here". That will ultimately dictate if the proposed choice is appropriate

Sir, I agree with Isabelle's opinion, because Eventhough nicotine acts  as insecticide, I has got high mammalian toxicity profile as it mimics ACh of mammals. If nicotine would be safe u imagine more than thousands of nicotine based insecticides would be there in the market especially in India , as we have lot availability of tobacco

I totally agree with opinion of Hareesha. Not necessary that being natural means safe on human beings.Many synthetics with exhaustive study on mammalian toxicity is available in market which are safe if used in permissible limits.

I agree with the opinions of Bolougne, Badiger, Benkovskaj, Barsics ets.  The nicotine may be considered more safe than synthetics   only because it degrades very fast in natural conditions.

Nicotine and anabasine have been already banned in many countries from the plant protection market long time ago, because of their high human tox and environmental impacts. It seems that even the newer chemical pesticides are less problematic than the 'good' old tabac extracts.

Nicotine is a pretty broad spectrum insecticide.  Pollinators are as susceptible to the chemical as are agricultural pests.  Considering the possible contamination of humans, and the broad spectrum of possible environmental impacts, it is not likely that nicotine would successfully fill a current gap in pest control.

Nicotine shreds were used to fumigate glasshouses in the UK in the past - effective wipeout of all insects, mites etc. but serious risks to the human operators lighting heaps of shreds and running fast and low to try to escape in time - NOT happy memories!

There are two ways to have screening of toxicants mainly pesticides, cidal and static, but environmentally, only those pesticdes are ecofreindly which are biodegradable in ecosystem. If natural pesticides are used most of them are catabolized by microbes and are simplified into non toxic compounds and thus come out from food chain and least persist in the medium. If pesiticides which are plant origin but used as pure compound with out any admixture also follow the same route as synthetic pesticides do. Hence, a compound isolated from plant source or same is synthesized in the laboratory shows two different activities. A chemical binds to other materials and stay  in non-degradable  from due to presence of strong energy bindings in planar rings, or in functional groups or having toxic heterocyclic groups.  Tobacco is one of know plant based insecticide used to check insect pests in China and India but its few components still persist in the medium and is not safe for small insects mainly larvae of soil insects.

Tobacco as spray and fumigant was widely used as pesticides for decades. It is now banned in developed countries, but may be still in use in less restricted places.

If you read the old literature on economic entomology, you will find

many reports of using the natural products from tobacco, the alkaloids

nicotine and anabasine, for insect control purposes. In fact, the toxic

compounds are effective against a wide variety of insect pests, but

unfortuantely also against beneficial insects. They are, specifically as

free bases ( but somewhat less so as sulfate salts) quite poisonous to

all warm blooded animals including birds, farm animals, pets, and

humans. In addition, a considerable "waiting period" between pesticide

application and product harvest has to be observed until commodities

treated with the alkaloids are safe for consumption. Skin contact is

dangerous because the alkaloids are absorbed through unprotected skin.

Also, beware of the fumes since nicotine, as all smokers know, is easily

absorbed by the lungs. Ingestion by humans may be fatal!

Nicotine and anabasine have systemic properties and doubtlessly qualify

as inexpensive renewable natural products. Nevertheless, their ecofriend-

liness is debatable.

Therefore, the compounds fell into disfavor a long time ago and were

replaced by some safer modern pesticides.

Unless you are a trained toxicological specialist dont use the compounds

without professional advice and proper registration.

Some more detail is available in Metcalf et al., eds. (1962). Destructive

and Useful Insects. Mc Graw Hill, New York, or in the Wikipedia entries for nicotine and anabasine, where all relevant information can be found.

Dear Sir,

Toxicity impact is different for different living (Man, animal, crop, etc) entities. To explore nicotine & anabasine as eco friendly bio-pesticides, it is needed to evaluate them for their detailed toxicity. e.g. Laboratory trials followed by LC50/LD50, RBD, SAS, residue analysis, etc. Afterwards one can conclude it is safe or not?

We use nicotine and anabasine from tobacco are used as the bio-pesticides of plant origin as non-systemic insecticide. However , these chemicals are toxic due to presence of Pyridine & N-methyl pyrrolide(Nicotin) and Pyridine & piperdine(Anabasine) to human being particularly to nervous system , so proper dose should be used so as to minimize the mammalian toxicity.