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India is recovering from the euphoria of the Green Revolution and battling the residual effects of the extensively used chemical fertilizers and pesticides in the country’s soils. The decade from 1980 to 1990 alone saw the area under pesticides in India, increased a whopping 20-fold, from six million hectares to 125 million hectares. After a high annual consumption of nearly 75000 MT reached in the early ’90s, interventions in the form of Integrated Pest Management (IPM) practices have only now started to show a declining trend in the use of pesticides in India. Interestingly, India’s consumption of pesticides per hectare is low (0.288 kg/ha) when compared with world averages—0.5 kg/ha against Korea’s 6.60 kg/ha and Japan’s 12.0 kg/ha. According to the pesticides industry statistics, India spends US $3/ha on pesticides compared with US $24/ha spent by Philippines, US $255/ha spent by South Korea and US $633/ha by Japan. Yet, despite a comparatively low use of pesticides in India, the contamination of food products in the country is alarming. About 20 per cent of Indian food products contain pesticide residues above tolerance level compared to only 2 per cent globally. No detectable residues are found in only 49 per cent Indian food products compared to 80 per cent globally. A pesticide is any substance or mixture of substances intended for preventing, destroying, repelling or mitigating any pest. Though often misunderstood to refer only to insecticides, the term pesticide also applies to herbicides, fungicides and various other substances used to control pests.

Pesticides and their metabolites have received particular attention in the last few years in environmental trace organic analysis because they are regularly detected in food products, surface/ground waters and soil strata throughout the world as consequence of their widespread use for agricultural and nonagricultural purposes. So it is the need of the hour to study the levels of pesticides residues in plants, water and soil and their fate in environment after its degradation.

It would be necessary to work out tolerance limits of pesticides residues in/on crops, soil and water and the efforts, therefore, are directed towards various residue analytical methods like TLC, GLC and HPLC etc. which are suitable for the purpose.

A pesticides residue is any substance or mixture of substances in food, agricultural commodities or animal feed resulting from the use of pesticides and includes any specified derivatives such as degradation products and impurities that are considered to be of toxicological significance.

Pesticide residue analysis (PRA) may be defined as the quantitative and qualitative analyses of the representative samples drawn from agricultural field, market and environment for pesticides and their toxic metabolites.

Chemicals in the form of insecticides ,fungicides and herbicides are extensively used in large numbers in agricultural production. Commercial production of some crops would be impossible if chemicals are not used. Small quantities of chemical residues often remain in such crops and the harvested grains and other products. The residues of pesticides  have been observed in small quantities (ppm level) in soil, water, agricultural produce  and even in animal tissues and their products like meat and  milk. They finally reach the consumer, namely, man (and even animals). Even the environment  is  now-a-days polluted with pesticides and other chemicals harmful to the humans. In view of the importance and seriousness of the problem the residues need to be estimated in the food and non-food products to assess their safety. Analytical details of a few pesticide residue procedures are presented below. Specialized texts may be consulted for  more extensive information.

Principle: Acetone is used for extraction the most nonionic pesticide residue, and residue are partitioned from acetone to dichloromethane/hexane phase. After removing traces dichloromethane, final extract is made up with acetone. This extract can be determined by GC with selective detectors FPD-P/NPD without cleanup. Further for organochlorine and synthetic pyrethroids extract should be cleaned up using florisil column. And for determination organophosphate extract should undergo to charcoal-celite cleanup.

India is an agrarian country where around 70% of the total population is engaged in farming activities. Agriculture and allied sectors are undoubtedly the largest livelihood provider of India, along with significant contribution towards the Gross Domestic Product (GDP) of the country. Agricultural production has been raised dramatically in the recent past to feed our burgeoning population with the help of modern inputs like fertilizers, pesticides, mechanical devices for tilling, seeding and irrigating the crops. With the advancement of agro-inputs, incidence of various kinds of pests also increases that hugely threaten our food security.

Crops are grown with the use of plant protection chemicals to boost production, enhance quality, and lengthen shelf life. Wherein the enormous use of pesticides which are having the longer half life period led to leave the residues in the different bodies of the ecosystem. Pesticide residues refer to the residual presence of pesticide active ingredients, their metabolites, or breakdown products in various environmental components subsequent to their application, accidental release, or disposal.

Analysis of residues gives insight on the type and extent of chemical contamination in an area, as well as how long it has been there. Before governments will approve the use of pesticides, they require comprehensive testing of their efficacy, environmental impact, and toxicology. A possible risk to human health arises from the presence of chemical residues and/or breakdown products in agricultural goods. Selective sampling plans can be used to learn more about pesticide traces in the environment, how they move about, and how quickly they degrade.

Pesticide: The act defines “pesticide” as any substance or other substance or product that is used to stop, kill, repel, or control insects, rodents, fungi, weeds, and other plants and animals that humans don’t need.

Introduction

The term pesticide refers to any chemical or mixture of chemicals intended for preventing, attracting, repelling, controlling or regulating a pest, including unwanted species of plants and animals during the production, shipment, transit, storage, processing or distribution of any food or agricultural commodity. The term includes compounds classified as insecticides, fungicides, herbicides, accaricides, rodenticides, plant growth regulators, sprouting inhibitors, chemosterilants, desiccants etc. The term excludes substances like animal drugs and food additives. Pesticides are chemicals used to destroy or control weeds, insects or other pests. The term pesticide residue refers to the remnants of the pesticide after weathering and it consists of the parent molecule and the degradation products which are toxicologically significant. In general, the pesticides, by virtue of their inherent toxic nature are recommended to be used as per Good Agricultural Practices (GAP) only. If GAP is not followed, contamination of the produce with the residues may pose significant health risk to consumers, non target organisms, biota and environment as a whole. When a pesticide is used for pest control purposes, they may reside in the form of metabolites.

Pesticide residues occur as the leftover of any pesticide after its application for pest control and it includes the parent compound and its toxic metabolites. Pesticide residue analysis may be defined as qualitative and quantitative analysis of samples drawn from agricultural field, market and environment for pesticides and toxic metabolites. Pesticide residues are invariably present in micro – quantities and generally estimated at ppm/ ppb levels. After application of the diluted spray solution, they are present at sub microgram levels in the substrate and hence their estimation at ppm or ppb levels is very cumbersome and need to be performed with utmost care. Moreover, the residue data generated should be accurate, reliable and reproducible. The level of residue in any edible commodity has to be below their prescribed maximum residue limits (MRL) value for market acceptance and below maximum permissible intake (MPI) for safety to consumers. Pesticide residue data are mainly utilised by regulatory authorities for estimation of MRLs and for assessing impact on human health and environment, particularly their adverse effect on non-target organisms. The detection of the pesticide residues must be confirmed beyond doubt and confirmation by GC-MS/MS or LC-MS/MS is generally acceptable. Since pesticide residues include parent compounds, isomers and toxic metabolites, appropriate methods of detection should be selected so that all the components are measured separately. Environmental samples/ market usually contain residues of large number of pesticides, for which multi residue methods are required for estimation/screening of such samples.

India is the world’s second largest producer of fruits, of which mango, banana, citrus, guava, grape, pineapple and apple are the major ones. Apart from these, fruits like papaya, sapota, aonla, phalsa, jackfruit, ber, pomegranate in tropical and sub-tropical parts and peach, pear, almond, walnut, apricot and strawberry in the temperate parts are also grown in a sizeable area. Date palm and fig cultivation is also finding favour in some areas. The major fruit growing states are Maharashtra, Tamil Nadu, Karnataka, Andhra Pradesh, Bihar, Uttar Pradesh and Gujarat.

Production of fruits in India is 44.04 million tones from an area of 3.72 million hectares. One of the bottlenecks in fruit production is the losses incurred by insect pest and diseases which necessitated the use of pesticides to curb the pest problem. Use of pesticides in India is very low 0.350–0.5 kg/hectare as compared to 7.0 kg/hectare in USA, 2.5 kg/hectare in Europe, 12 kg/hectare in Japan and 6.6 kg/hectare in Korea. Despite of low pesticide consumption in India, there is a great problem of pesticide residues vis-a-vis other countries and these residues have entered into food products and underground water because of non-prescribed use of chemical pesticides, wrong advice and supply of pesticides to farmers by vested interests, non-observance of prescribed waiting period, pre-marketing pesticide treatments during storage and transport, use of sub-standard pesticides, effluents from pesticide manufacturing units, continued use of persistent pesticides for public health programme, lack of awareness and lack of aggressive educational programmes for farmers/consumers.

Spices are defined as “A strongly flavored or aromatic substance of vegetable origin, obtained from tropical plants, commonly used as a condiment”. American Spice Trade Association (ASTA) defines spices as “Any dried plant product used primarily for seasoning purposes”. The word “spice” came from the Latin word “species,” meaning specific kind. The name reflects the fact that all plant parts have been cultivated for their aromatic fragrant, pungent or any other desirable properties including the seed (aniseed, caraway, coriander), leaf (cilantro, kari, bay, mint), berry (allspice, juniper, black pepper), bark (cinnamon), kernel (nutmeg), aril (mace), stem (chives), stalk (lemongrass), rhizome (ginger, turmeric, galangal), root (lovage, horse radish), flower (saffron), bulb (garlic, onion), fruit (star anise, cardamom, chile pepper) and flower bud (clove). Spices are distinguished from herbs, which are leafy, green plant parts used for flavoring purpose. Herbs, such as a basil or orengano, may be used fresh and are commonly chopped in to smaller pieces; spices however are dried and usually ground in to a powder (Anonymous, 2007).

In ancient times, spices were as precious as gold, and as significant as medicines, preservatives and perfumes. India is known as the home of spices and produces a wide variety of spices like black pepper, cardamom (small and large), ginger, garlic, turmeric, chilli and a large variety of tree and seed spices. These have nutritionally insignificant quantities as a food additive for the purpose of flavoring. They are good not only for our taste buds but also for our health. They have medicinal properties and also used as preservatives. Spices are well known appetizers, digestives and considered essential in culinary art all over the world. Some of them have antioxidant properties, while others possess strong antimicrobial and antibiotic activities. Spices increase the secretion of saliva rich in ptyalin, which facilitates starch digestion in the stomach, rendering the meals, which are rich in carbohydrates, more digestible. They inhibit thrombus formation and accelerate thromobolysis (Anonymous, 2007a).

The noun vegetable means an edible plant or part of a plant, but usually excludes seeds and most sweet fruits. This typically means the leaf, stem, or root of a plant. Vegetables are eaten in a variety of ways, as part of main meals and as snacks. The nutritional content of vegetables varies considerably, though generally they contain little protein or fat (Woodruff,1995 and Whitaker, 2001) and varying proportions of vitamins such as Vitamin A, Vitamin K and Vitamin B6, provitamins, dietary minerals and carbohydrates. They contain a great variety of other phytochemicals, some of which have been claimed to have antioxidant, antibacterial, antifungal, antiviral and anticarcinogenic properties (Gruda, 2005; Steinmetz and Potter,1996). Some vegetables also contain fiber, important for gastrointestinal function. Some contain important nutrients necessary for healthy hair and skin as well. However, vegetables often also contain toxins and antinutrients such as á-solanine, á-chaconine,(Science direct) enzyme inhibitors (of cholinesterase, protease, amylase, etc.), cyanide and cyanide precursors, oxalic acid, and more (Bad Bug Bock > BBB–Clostridium botulinum). Depending on the concentration, such compounds may reduce the edibility, nutritional value, and health benefits of dietary vegetables. Cooking and/or other processing may be necessary to eliminate or reduce them. Diets containing recommended amounts of fruits and vegetables may help to lower the risk of heart diseases and two type of diabetes. These diets may also protect against some cancers and decrease bone loss. The potassium provided by vegetables may help to prevent the formation of kidney stones.

Pesticides sustain food production and control disease and pests. They are vital for crop production and instrumental in continuous increase in food production. The consumption of pesticide in India is one of the lowest in the world. India uses a low amount of 0.5 kg/hectare pesticide compared to 7.0 kg/ hectare by USA, 2.5 kg/hectare by Europe, 12 kg/hectare by Japan and 6.6 kg/ hectare by Korea. However, despite the low consumption of pesticides, India has more problem of pesticide residues vis-a-vis other countries and these have entered into food products and underground water because of

Pesticide Resistance

Resistance to pesticides may be defined as ‘a heritable change in the sensitivity of a pest population that is reflected in the repeated failure of a product to achieve the expected level of control when used according to the label recommendation for that pest species.

Abstract

Tea (Camellia sinensis L. O. Kuntze), a foliage crop of Sub-Himalayan Terai-Dooars has Tea mosquito bug (Helopeltis theivora)(TMB), looper caterpillars [Hyposidra talaca, Hyposidra infixaria, Biston (=Buzura) suppresseria] and Red spider mite (Oligonychus coffeae)(RSM) as major pests. In conventionally managed tea plantations, synthetic pesticides and acaricides are routinely applied. The pesticide-exposed pest populations show higher tolerance level as evident in their increased LC50 values. Augmented activities of detoxifying enzymes viz. general esterases (GE), glutathione S–transferases (GST) and cytochrome P450 mediated monooxygenases (CYP) were recorded in the pesticide-exposed pest populations. Sub–lethal exposure to monocrotophos (36% SL) enhanced the tolerance level in adult TMB by 105 fold through three generations. Increased activity of GE was evident in the pesticide-exposed populations of the tea loopers. Activities of GE and GST  in RSM were significantly higher in acaricide-exposed population. Present studies can help developing enzyme-based assay kit for determining level of pesticide-resistance. Integrated resistance management has become an integral part of modern day IPM practices. Adoption of newer chemicals, and cultural practices can minimise synthetic pesticide applications, thereby help reducing resistance development in pests.

Insecticides possess toxicity towards both pest organisms and human beings. Nevertheless, the potential harm to humans and non-target animal species can be mitigated by implementing appropriate safety measures. The ingestion or prolonged dermal exposure to most insecticide s can result in deleterious effects, whether intentional or accidental. Inhalation of insecticide particles may occur during the spraying process, and there is an associated risk of contamination of drinking water, food, or soil. The issue of safety is consistently a concern when utilizing insecticide s. Exposure to insecticide concentrates or vapour drift has the potential to cause harm to applicators, bystanders, and the surrounding environment. It is imperative to exercise specific precautions when engaging in the activities of transportation, storage, and handling. Individuals who are engaged in the handling and application of insecticide s are required to possess knowledge and adhere to appropriate safety protocols in order to mitigate potential risks. The foundation of ensuring insecticide safety lies in the selection of an appropriate product. The preservation of safety is of utmost significance in the various stages of insecticide management, including storage, transportation, mixing, and loading. The safe execution of equipment cleanup and maintenance is imperative, as it necessitates the proper disposal of unwanted insecticide s and empty insecticide containers. Regular cleaning and maintenance of spray equipment is essential in order to mitigate the occurrence of leaks. Furthermore, individuals who are involved in insecticide application should undergo comprehensive training to ensure their adeptness in handling these substances safely.

History

 • The fossil evidence also indicates the presence of plant diseases 250million years ago.

 • The diseases caused by fungi and nematodes were discovered by Monocernin 1735.

 • Johan Needham (1743) identified wheat gall caused by a nematode.

 • Adolf Mayer (1886), demonstrated the transmission of Tobacco mosaicvirus (TMV).

 • EF Smith (1890) described bacterial wilt in cucurbits.

• The thrips (Thysanoptera) as vectors of plant viruses were identified thescientific studies made by Samuel and his team.

 • Karl Maramorosch (1952) demonstrated the multiplication of Asteryellows virus (AYV) in leafhopper vector.

 • The mite Aceriatulipae has been identified as a vector of Wheat streakmosaic virus by JT Slykhuis in 1955.

 • The term “viroid” (viruses without protein coat) was coined by TO Dienerduring 1971.

Introduction
Pesticides play a crucial role in agriculture. During the period of the Green Revolution, the use of pesticides increased dramatically (Matson et al., 1997). According to the Environmental Protection Agency (EPA), pesticides can be defined as compounds that are used for the destruction, repulsion, or prevention of organisms that can be harmful to cultured crops (pests) as well as affect the regulation of plant growth. They are categorized based on several factors, such as their chemical composition (organophosphates, pyrethroids, neonicotinoids, etc.), based on the types of pests they eradicate (herbicides, insecticides, fungicides, etc.), and application methods. Although each pesticide has a distinct purpose, they all have comparable advantages. Some of the primary benefits of pesticide usage are the prevention of disease andan increase in yield, whereas secondary benefits include economic efficiency, an increase in food quality, facilitation of sustainable agriculture, improving public health, etc. However, the extensive use of pesticides has its consequences. These pesticides are meant to control or eliminate pests, but their toxicity could end up in unexpected areas. Its utilization poses significant harm to the environment, particularly to aquatic ecosystems. While they are essential in agriculture, their unregulated application leads to environmental degradation. The level of toxicity is influenced by factors such as pesticide concentration, mode of action, chemical composition, and persistence in the environment. Pesticides can cause both acute as well as chronic health effects. Through runoff or leaching, they indirectly enter water bodies, harming aquatic flora and fauna. A 2001 study revealed that over 90 percent of fish and water samples collected from various streams contained traces of one or more pesticides (Kole et al., 2001).

Pesticide Toxicity

Chemical tactics to manage pests can include many types of compounds. Some merely repel or confuse pests. Some interfere with weed photosynthesis, insect molting processes or development in some way. Others, including some botanical and most conventional insecticides are broadly toxic to living systems. The term pesticide literally means “pest killer". Generally speaking, when using pesticides, we are trying to garner the advantages of using pesticides while minimizing the risk to humans and other non-target organisms. Risk to humans of pesticide use is often described as:

Introduction

In the thirst of modernization and industrialization man has contributed pollution to the life and ecology of plants, animals and microbes. Increased demand for food and fiber has lead to the chemicalization of agriculture and we have reached on such a stage that modern agriculture is dependent on high yielding varieties, which can only be grown under the influence of fertilizers and pesticides. Pesticides are the man made chemicals which are being used to produce enough cheap food. In India, 90,000 MT of technical grade pesticides are used annually to control pests and plant diseases. The pesticides are classified as insecticides, fungicides, weedicides, herbicides, nematodicides and rodenticides; of which insecticides constitutes 77% of the total pesticides used in different agricultural and animal husbandry practices and in public health operations.

Introduction

The toxicant must be able to be applied effectively in order to come into touch with the pest or leaf and to leave a uniform and permanent deposit on the plant surface. Pesticide in chemically pure form is known as technical grade pesticides. These cannot be applied as such due to high toxicity and complex physical properties. They are converted into a ready to-use form known as formulation. Formulation converts the technical grade pesticide into a product which can be suitably diluted & applied by practical methods. Which have homogeneous distribution over large area, convenient to handle and more attractive to the pest.

There are broadly five categories of crop protection products

Insecticides: Insecticides provide protection to the crops from the insects by either killing them or by preventing their attack. They can be further classified based on their mode of action: