Biocides & fumigants play an important role in agriculture, industry and health. They contribute to the conservation and durability of a multitude of raw materials and manufactured products during production, storage and final use. In Ayurveda, there are many such measures described in the management of individual and social health & disease.

In Carakasamhita (CarakasaĽhit˘) an independent chapter dealing with Janapadodhvamsa (JanapadodhvaĽsa)(epidemics) has many such references dealing with measures for the purification of air, water and soil. These measures can be broadly grouped under preventive and curative measures. These are aimed at control and elimination of harmful macro & microorganism e.g. use of preservatives for drugs, food, beverages; use of fumigants to kill or drive away the harmful pathogens and insects etc. However, these natural biocides and fumigants are mostly scattered in the context of control and treatment of various diseases and very few of them have been studied on modern scientific parameters for their nature and mode of action. These plant, animal or mineral derivatives usually appear to have some common property e.g. they possess strong bitter or pungent taste, strong unpleasant smell and a few are poisonous, if consumed in sufficient quantity.

In terms of protection from and prevention of disease or unwanted harmful animals and insects we find use of certain trees and plants e.g. Nimba (Azadirachta indica A. Juss.), Tulasi (Ocimum sanctum Linn.), Vanatulasi (Ocimum basilicum Linn.) in and around houses, evening fumigation of house with Nimbapatra (leaves of Azadirachta indica A. Juss.), Sarsapa (seeds of Brassica campestris Linn.),Sarjarasa (exudates of Shorea robusta Gaertn. f.), Hingu (exudates of Ferula foetida Regel) etc. on charcoal or cow dung fire to repel insects, or purify the places like Vranagara (operation theater), Sutikagara (puerperal chamber). Fumigants are also used in disinfecting the fermentation pots used for Asava & Arista.

There are several Dhupana (fumigation) formulations to combat foul smell emanating from Vrana (wound), Yoni (vagina), Gatra (body). Fumigants were also used to disinfect the atmosphere and various Dhupa (fumigants) e.g. Dasangadhupa and other Havisa (oblation for burning) of Ghrta (clarified butter), Guggulu(exudates of Commiphora wightii Bhandari), Devadarukastha (woods of Cedrus deodara (D.Don) G.Don) etc. were used whenever some epidemic broke out in the villages.

For the prolong preservation of potency and prevention from getting rotten; the drugs & dietary items were extensively stored in or formulated with Ghrta (clarified butter), Taila (vegetable oil), honey, Asava/ Arista.

Caraka in Sutrasthana 3rd chapter (Aragvadhiyam) has described 32 Lepa & Pradeha (drugs for local application) consisting of various drugs including formulations in the management of skin affections like scabies, eczema, leprosy etc. There are fifteen Kusthahara (curing skin diseases including leprosy) formulations and in each group some drugs are biocides while others are soothing or healing agents. There is one Sarira-daurgandhahara (remover of foul smell from body) Pradeha (drugs for local application) also. There are many Lepa, Pradeha (drugs for local application) and drugs to be worn on the body of an infant to cure some of the Grahabadha (Paediatric idiopathic syndrome) of the infant.

Likewise in Sutrasthana 4th chapter there are Kusthaghna (drugs curing skin diseases including leprosy), Kandughna (drugs curing skin diseases with itching), and Krmighna (anthelminthics) Mahakasaya (great decoctions) that consist of biocides as well. These are enumerated as Khadira (Acacia catechu(Linn. f.) Willd.), Haritaki (Terminalia chebula (Gaertn.) Retz.), Amalaki (Phyllanthus emblica Linn.), Haridra (Curcuma longa Linn.), Bhallataka (Semecarpus anacardium Linn.f.), Saptaparna (Alstonia scholaris (Linn.) R. Br.), Aragvadha (Cassia fistula Linn.),Karavira (Nerium indicum Mill.), Vidanga (Embelia ribes Burm. f.) and Jatipravala (young leaves of Jasminum officinale Linn.) being Kusthaghna (drugs curing skin diseases including leprosy).

Candana (Pterocarpus santalinus Linn. f.), Nalada (Vetiveria zizanioides (Linn.) Nash), Aragvadha (Cassia fistula Linn.), Naktamala (Pongamia pinnata (Linn.) Pierre), Nimba (Azadirachta indica A. Juss.), Kutaja (Holarrhena antidysenterica (Roxb. ex Flem.) Wall. ex DC), Sarsapa (seeds of Brassica campestris Linn.), Madhuka (Glycyrrhiza glabra Linn.), Daruharidra (Berberis aristata DC.) and Musta (Cyperus rotundus Linn.) as Kandughna (drugs curing skin diseases with itching).

Aksiva (Moringa pterygosperma C.F. Gaertn.), Marica (fruits of Piper nigrum Linn.), Gandira (Coleus barbatus(Andrews) Benth.), Kebuka (Costus speciosus (Koen. ex Retz.) Smith), Vidanga (Embelia ribes Burm. f.), Nirgundi (Vitex negundo Linn.), Kinihi (Albizia procera (Roxb.)Benth.), Goksura (Tribulus terrestris Linn.), Vrsaparnika (Ipomoea maxima (Linn.f.) G.Don.), and Akhuparnika (Merremia gangetica(Linn.) Cufodont) as Krmighna(anthelmintics).

In Susrutasamhita sutrasthana chapter-38 (Dravyasangrahaniya) the Arkadigana plants viz. Arka (Calotropis procera Dryand ex W.Ait.), Alarka (Calotropis gigantea (Linn.) Ait.f.), Karanjadvaya (Pongamia pinnata (Linn.) Pierre), & (Holoptelea integrifolia (Roxb.) Planch.), Nagadanti (Croton oblongifolius Roxb.), Mayuraka (Achyranthes aspera Linn.), Bhargni (Clerodendrum divaricatum Jack), Rasna (Pluchea lanceolata Oliv. & Hiern), Indrapuspi (Gloriosa superba Linn.), Ksudrasveta (Albizia lucidaBenth.), Mahasveta (Albizia procera (Roxb.) Benth.), Vrscikali (Pergularia daemia (Forsk.) Chiov.), Alavana (Celastrus paniculatus Willd.) and Tapasavrksa (Balanites aegyptiaca (Linn.) Delile) are said to have the property to cure Krmi (worms), Kustha (skin diseases including leprosy) and Vranavisodhana (wound cleansing & purifying).

The Surasadigana plants viz. Surasa (Ocimum sanctum Linn.), Svetasurasa (Ocimum canum Sims.), Phanijjaka (Origanum majorana Linn.), Arjaka (Orthosiphon pallidus Royle ex. Benth.),Bhustrna (Cymbopogon martini (Roxb.) Wats.), Sugandhaka (Leucas martinicensis R.Br.), Sumukha ('Brassica juncea (L) Czern.),Kalamala (Ocimum basilicum Linn.), Kutheraka (Ocimum basilicumLinn.), Kasamarda (Cassia occidentalis Linn.), Ksavaka (Centipeda minima (Linn.) A.Br. & Aschers), Kharapuspa (Origanumspecy),Vidanga (Embelia ribes Burm. f.), Katphala (Myrica esculentaBuch.-Ham. ex D. Don), Surasi (Limonia crenulata Roxb.), Nirgundi (Vitex negundo Linn.), Kulahala (Sphaeranthus indicus Linn.), Undurukarnika (Merremia gangetica (Linn.) Cufodont), Phanji (Rivea ornata Choisy),Pracibala (Peristrophe paniculata (Forssk.) Brumm.), Kakamaci (Solanum nigrum Linn.) and Visamustika (Strychnos nuxvomica Linn.) are also said to be Krmighna(anthelmintics) and Vranasodhana. (Wound cleansing & purifying).

In recommendation of plants for use as toothbrush Caraka enumerated some plants e.g. toothbrush sticks made of Nimba (Azadirachta indica A. Juss.),Karanja (Pongamia pinnata (Linn.) Pierre), Karavira (Nerium indicum Mill.), Arka (Calotropis procera Dryand ex W.Ait.) etc. that are disinfectant and remover of foul smell from mouth.

In Caraka Cikitsasthan 23rd chapter (Visacikitsa) there is description of one formulation for fumigation, which would kill serpents, rats, insects and tiny insects of clothes. The plants enumerated are Jatu (Laksa i.e. secretion of Lacifer lacca), Sevya (roots of Vetiveria zizanioides (Linn.) Nash), Patra(leaves of Cinnamomum tamala Nees), Guggulu (exudates of Commiphora wightii Bhandari), Bhallataka (fruits of Semecarpus anacardiumLinn.f.), Kakubhapuspa (flowers of Terminalia arjuna (Roxb.) Wight &Arn.), Sarjarasa (exudates of Shorea robusta Gaertn. f.) and Sveta(white flower variety of Clitoria ternatea Linn.). In Vranacikitsa also there are formulations for local irrigation, application and fumigation to be used for vranasodhana (wound cleansing & purifying), which act as disinfectant. Natural biocides are also used in various types of Krmiroga e.g. Udarakrmi (intestinal worms), Krmija-siroroga (Headache due to hydatid cyst/Taenia solium/ Taenia Echinococcus), Krmija-hrdaroga (Heart disease with infective pathology), Vranakrmi (wound infested with worms), Krmidanta (Carious ooth/dental caries) etc.

In Astangasamgraha Uttarasthana, chapter-1(Balopacaraniya) it is described to tie a cotton pouch containing Hingu (exudates of Ferula foetida Regel), Vaca (rhizome of Acorus calamusLinn.), Turuska (Liquidambar orientalis Mill.) and Sarsapa (seeds of Brassica campestris Linn.), on the upper frame of door and head side of bed (cradle)and also in the neck of infant and mother for protection which possibly acts as repellent for insects etc. Further there is mention of fumigants for baby’s apartment consisting of dried crow feathers along with Trivrta, Vaca (rhizome of Acorus calamus Linn.), Kustha (Saussurea lappa Clarke),Srivesta (exudates of Pinus roxburghii Sarg.), Sarsapa (seeds of Brassica campestris Linn.), added with little Ghrta (clarified butter).

Further in Astangasamgraha Uttarasthana, chapter-30 (Vranapratisedha) fumigation with Srivestaka (exudates of Pinus roxburghii Sarg.), Sarjarasa (exudates of Shorea robusta Gaertn. f.), Sala (Shorea robusta Gaertn. f.), Devadaru (Cedrus deodara (D.Don) G.Don), Simsapa (Dalbergia sissoo Roxb. ex DC.),Khadira (Acacia catechu (Linn. f.) Willd.), Asana (Pterocarpus marsupium Roxb.), Kaidaryasara (Melia azedarach Linn.), Yava (Hordeum vulgare Linn.), Madhucchistha (bee wax), Bhurjapatra (Betula utilis D.Don), Ksauma (Linum usitatissimum Linn.) and Ghrta (clarified butter)are indicated to allay exudation and pain of wounds.

In Astangasamgraha Sutrasthana chapter-38 (Sastrakarmavidhi) also there is mention of Vrana-raksoghna Dhupa consisting of Guggulu (exudates of Commiphora wightii Bhandari), Agaru (Aquilaria malaccensis Lam.), Sarjarasa (exudates of Shorea robusta Gaertn.f.), Vaca (rhizome of Acorus calamus Linn.), Gaura-sarsapa (white seeds of Brassica campestris Linn.), Hingu (exudates of Ferula foetidaRegel), Lavana (salt), Nimbapatra (leaves of Azadirachta indica A. Juss.), and Ghrta (clarified butter) for the fumigation of wound. This also finds mention in Uttarasthana chapter-1 for the protection of newborn infant.

Astangasamgraha Uttarasthana chapter-8(Bhutapratisedha) contains many formulations, which appear consisting of natural biocides and fumigants. Likewise the external therapeutic measures to prevent or cure various infantile Grahabadha (Paediatric idiopathic syndrome)also appear usually consisting of similar nature of drugs.

It may be mentioned here that Ayurveda was intricately woven with culture and religion in the society and natural biocides and fumigants were widely used on a variety of pretext aimed at prolonging life and providing health, happiness and prosperity.