Agrochemicals
Agrochemicals are chemical products used in agriculture to enhance crop production and protect plants from pests, diseases, and weeds. They include fertilizers, pesticides, and herbicides. While agrochemicals can increase agricultural productivity, their use also raises concerns about environmental and human health impacts, soil degradation, and water pollution.
5 Key excerpts on "Agrochemicals"
eBook - ePub- Johann F. Moltmann, D.M. Rawson(Authors)
- 2020(Publication Date)
- CRC Press(Publisher)
...5 PESTICIDES AND ENVIRONMENTAL CHEMICALS 5.1 PESTICIDES 5.1.1 Classification Definition and Description Pesticides — also known as plant protectant agents or crop protection products — are (primarily chemical) substances designed to combat and control pests on cultivated plants or carriers of viral or bacterial diseases. They also include substances to combat vegetational competitors (weeds) as well as fungal plant diseases. So-called growth regulators are a special type of agent. By influencing the vegetative growth of plants, they support the stability of grain stalks or simplify harvesting by inducing the simultaneous abscission of ripe olives. Chemicals are also utilized to combat disease vectors which are harmful to human beings and domestic animals, both in areas out of doors and in the home. Such agents are sometimes referred to as biocides. “Agrochemicals”, which is the common term in English-speaking areas, is often used to mean all of the synthetic substances — including mineral fertilizers — which are applied for specific purposes in agriculture. In addition to the active ingredient, many pesticides contain a large share of formulation aids, which serve as protective colloids, for example, or help to improve the application characteristics. Aside from fertilizers, agents for crop treatment and disease vector control are the only chemicals which are intentionally released in the environment. This is the reason why, unlike other environmental chemicals, they were among the first substances to be thoroughly tested for their fate and effect. The German Agency for Technical Co-operation (GTZ) has made an initial attempt to trace and assess the various stages in the “life”of a pesticide a given developing country, in the form of an ecological information system (KNIRSCH, 1993)...
eBook - ePub- Shayne C. Gad, Shayne C. Gad(Authors)
- 2018(Publication Date)
- CRC Press(Publisher)
...9 Agricultural Chemicals Regulation, Risk Assessment, and Risk Management Elliot Gordon CONTENTS Introduction Target Audience Evolution of the Agrochemical Industry Agrochemical Regulation History References Agency Documents Literature Handling of References Industry Groups Regulators Agrochemical Risk Assessment Hazard Identification Acute Studies Subchronic Studies Chronic Studies Developmental and Reproductive Toxicity Genetic Toxicity Studies Metabolism Studies Modes of Action Hazards to Nontarget Organisms Endocrine Disruption Dose Response Exposure Assessment Occupational Exposure Dietary Exposure Dermal Absorption Aggregate and Cumulative Exposure Models Risk Characterization Safety Factors/Uncertainty Factors Agrochemical Risk Management Occupational Risk Management Product Formulation Mixing Scenarios Personnel Protective Equipment Reentry Interval Dietary Risk Management Risk Communication Considerations for the Agrochemical. Toxicologist Active Ingredient Pre-Application Meeting Pesticide Registration Improvement Extension Act (PRIA 3) Waivers Electronic Submissions Efficacy Data Study Monitoring Good Laboratory Practice Regulations Flagging Criteria and FIFRA 6(a)(2) Reporting Petition for Registration Budgets and Timelines Experts Inerts Formatting Conclusion Acknowledgments References INTRODUCTION T ARGET A UDIENCE Toxicologists work in many different roles and areas and are involved in the hazard and risk assessment of chemicals covering a wide variety of uses and applications. In agrochemical regulatory toxicology, toxicologists work with other scientific experts, for example, ecotoxicologists, chemists, agronomists, to support the registration and safe use of pesticides, which include insecticides, herbicides, fungicides, rodenticides, bactericides, insect and plant growth regulators, insect and animal repellents, and biopesticides (derived from certain natural materials)...
eBook - ePub- John W. Dover, John W. Dover(Authors)
- 2019(Publication Date)
- Routledge(Publisher)
...Thus, the risk of contamination of these important semi-natural habitats with harmful pesticides is a matter with significant ecological and economic implications. Understanding the distribution of pesticides in the environment and their potential effects on biological communities is crucial to properly assess current agricultural management and schemes aiming to boost biodiversity in farmland. Exposure of flora and fauna of hedgerows and field margins to agricultural pesticides The environmental fate of agricultural pesticides is related to their physico-chemical properties, method and rate of application, abiotic and biotic characteristics of the environment, and meteorological conditions (Graham-Bryce 1981). When a pesticide is applied to a crop or soil, it enters a dynamic ecosystem, where it can move from one part of the system to another (e.g. uptake by plants from soil), degrade in situ, or move out of the system into other systems (Navarro et al. 2007). Pesticides degrading completely and leaving no toxic metabolites become harmless, whereas those that move to other systems or persist have more potential to do environmental damage (Goulson 2013). Though highly variable, a considerable fraction of the initial amount of pesticide applied to crops is dispersed into the environment via air drift, leaching, and runoff, contaminating surrounding soils, surface water, and groundwater (Barbash & Resek 1996; Bonmatin et al. 2015) and thus providing multiple routes for chronic (and sometimes acute) exposure of non-target flora and fauna. Routes of exposure for non-target flora There is clear evidence that plants in agricultural environments and neighbouring areas are frequently contaminated with variable levels of pesticides and their metabolites (David et al. 2016; Long & Krupke 2016)...
- Miguel Altieri, Clara Nicholls(Authors)
- 2018(Publication Date)
- CRC Press(Publisher)
...Economically, agricultural burdens include the need to supply crops with costly external inputs, since agroecosystems deprived of basic regulatory functional components lack the capacity to sponsor their own soil fertility and pest regulation. Often the costs also involve a reduction in the quality of life due to decreased soil, water, and food quality when pesticide, nitrate, or other type of contamination occurs. Clearly, the fates of agriculture and biodiversity are intertwined. It is possible to intensify agriculture in a sustainable manner in order to secure some of the remaining natural habitats, thus ensuring the provision of environmental services to agriculture. Agroecological forms of intensification can also enhance the conservation and use of agro-biodiversity, which can lead to better use of natural resources and agroecosystem stability (Gliessman, 1999). THE NATURE OF BIODIVERSITY IN AGROECOSYSTEMS Biodiversity in agroecosystems can be as varied as the crops, weeds, arthropods, or microorganisms involved or the geographical location and climatic, edaphic, human, and socioeconomic factors. In general, the degree of biodiversity in agroecosystems depends on four main characteristics of the agroecosystem (Southwood and Way, 1970): • The diversity of vegetation within and around the agroecosystem • The permanence of the various crops within the agroecosystem • The intensity of management • The extent of the isolation of the agroecosystem from natural vegetation The biodiversity components of agroecosystems can be classified in relation to the roles they play in the functioning of cropping systems...
eBook - ePubSoil and Fertilizers
Managing the Environmental Footprint
- Rattan Lal, Rattan Lal(Authors)
- 2020(Publication Date)
- CRC Press(Publisher)
...The dependence of fertilizers should be minimized, and these must be used as amendments following scientific guidelines (e.g., soil test, crop requirement). Factors affecting the choice of site-specific strategies for the use of fertilizers include biophysical, socioeconomic, cultural, and others related to the human dimensions. Important among biophysical parameters are soil type, climate, farming/cropping system, terrain, season, and weather patterns during the season. Pertinent issues of the human dimensions, especially in developing countries with predominantly small landholders, are infrastructure (e.g., roads, access to market, credit availability), institutional support (e.g., extension services, IT communication), and education and technical skills of the farming community (Figure 14.5). These factors vary among ecoregions and biome and have strong implications for the overall goal of judicious management of the environment and of human resources (Figure 14.5). 14.4 ADDRESSING THE FERTILIZER ADDICTION 14.4.1 G LOBAL F OOD D EMAND BY 2050 The projected increase in global agricultural production of 60% by 2050 compared with that of 2005–07 (FAO 2012) necessitates a closer look at the role of fertilizers in enhancing and sustaining food production. Excessive and indiscriminate use of chemical fertilizers can have severe environmental and sustainability concerns and can also adversely affect soil quality (Kotschi 2013; Mulvaney et al. 2009). Thus, site-specific options need to be considered to minimize dependence on the use of chemical fertilizers. Pedercini et al. (2014, 2015) suggested sustainable management of SOM as one of the options because increasing SOM can enhance soil and crop resilience. 14.4.2 M ANAGING S OIL O RGANIC M ATTER AND S OIL Q UALITY Restoration of SOM in depleted and degraded soils can improve soil quality and functionality and decrease the rate of fertilizer application...
