Pesticides 

Reference to the design of new insecticides nontoxic to the environment and the public emphasizing optimal food production with greater safety. Some 30 international experts examine topics including new types of active molecules among natural products and animal toxins; insect metabolic and organ systems as sources of information leading to more selective chemicals, safer ways of utilizing existing compounds, recently discovered modes of action including cuticle synthesis inhibitors, juvenile hormone inhibitors and anti-juvenile hormones, pesticide use reduction through improved application techniques and new management systems. Providing extensive bibliographic citations, Safer Insecticides is essential reading for biologists, environmental researchers, biochemists; organic, medicinal, agricultural and pesticide chemists; entomologists; toxicologists and regulatory personnel.

The commercial and widespread availability of synthetic pesticides has transformed approaches to pest management, emphasizing the use of off-farm inputs and control as opposed to the management of pest problems. Some attempts have been made to substitute pesticides with ‘agrobiologicals’, the biological equivalents of synthetic pesticides. These include biopesticides based on bacteria, fungi, viruses and entomopathogenic nematodes and a range of other offfarm inputs that include pheromones and macrobiological agents such as predators and parasitoids. Other alternatives to chemicals include the use of pest resistant crop cultivars including transgenic crops and on-farm techniques such as crop rotations, intercrops, tillage systems, modification of planting dates and sowing densities, and overall improved habitat management. These options can be used individually or as part of integrated systems working at the pest, crop, farm or agroecosystem level. This chapter places pesticides use (both chemical and biological) in the wider context of pest management (including IPM – integrated pest management), and provides examples of where there has been widespread change and adoption of alternatives to chemicals.

Many pesticides and chemicals are not biodegradable, and due to bioaccumulation, can enter into food chain and ultimately affect human and animal health. Environmental exposure of pesticides to humans through ecosystems may be during cropping/agriculture practices, consumption of food materials or air inhalation etc. Without pesticides or agricultural chemicals (herbicides, insecticides, rodenticides, fungicides and plant growth regulators), crop yield could drop by as much as a third and food prices would increase by as much as 75%. In India, 145 pesticides are registered for use at present and production has increased to approximately 85,000 metric tones. Though consumption in India is just about 0.5 kg/ha, but 51% food commodities are contaminated pesticide residues. Toxicity of pesticide is measured according to a number of indices (such as oral and dermal LD50) based on tests carried out on laboratory animals. They act mainly on receptors. In agriculture, mixing–loading step is the most contaminated task in open field accounting for two-thirds of the total daily exposure. Adverse health effects include acute and persistent injury to the nervous system, lung damage, injury to reproductive organs, and dysfunction of the immune and endocrine systems, birth defects and cancer. Even small amounts of some of these chemicals cause death; disrupt hormones and reduce the ability to successfully reproduce; and have been associated with specific cancers. Better understanding of the patterns of exposure, the underlying variability within the human population, and the links between the animal toxicology data and human health effects will improve the evaluation of the risks to human health posed by pesticides. Improving epidemiology studies and integrating this information with toxicology data will allow the human health risks of pesticide exposure to be more accurately judged by public health policy makers. There is need to educate all farmers for judicious use of pesticides, use of biotechnology and bio-pesticides, use of pesticides obtained from natural products such as Azadirachta indica (neem) via proper application of integrated pest management (IPM) programs would positively reflect on human health, agriculture, biodiversity and ecosystem management to minimize environmental problems caused by pesticides.

Pesticides are an important part of crop production worldwide, however their use poses a threat to potable water sources. Seasonal use of pesticides can cause increased concentrations to be detected at potable water abstraction sites as a shock load which can be difficult for conventional treatment processes to deal with. Concentrations of pesticides above 0.1 µg/L in drinking water contravene the regulations as laid out in the Drinking Water Directive and cause significant reputational and financial impact to water companies. This review considers the relationships between the pesticides that have caused compliance failures and their physico-chemical properties, and factors such as weather and rainfall. It was found that over 50% of the pesticide compliance failures in England and Wales were caused by the molluscicide metaldehyde and that the majority of the problematic pesticides are considered to be polar and mobile. The review looks in further detail at five different pesticides with differing physico-chemical properties known to have caused compliance failures and to be of particular concern for water companies. In addition adsorption media which could be utilised in agricultural catchments were investigated to understand whether they could be applied to prevent the onward contamination of potable water sources.

The aim of this work was to compile the most important aspects of CI as a strategy for the degradation of pesticides. We discuss the main targeted chemical substances, the used microorganisms, materials, and techniques, as well as their advantages, and limitations We highlight increases in the percentage of degradation, greater stability, protection, and tolerance to pesticides when a CI strategy is implemented. Finally, the requirements for deepening our understanding of the involved kinetic, molecular, and transfer processes are discussed, particularly for their application in situ