UPSC MainsGEOGRAPHY-PAPER-I201920 Marks
हिंदी में पढ़ें
Q7.

Discuss the use of chemical fertilizers, pesticides and insecticides in agriculture and its impact on human health.

How to Approach

This question requires a multi-faceted answer, addressing the use of chemical inputs in agriculture and their subsequent health impacts. The answer should begin by defining these inputs and their role in boosting agricultural productivity. It must then delve into the specific health consequences, categorized by the type of chemical used (fertilizers, pesticides, insecticides). A balanced approach is needed, acknowledging the benefits alongside the harms. The structure will follow: Introduction, Use & Benefits, Health Impacts (categorized), Mitigation Strategies, and Conclusion. Focus on specific examples and data where possible.

Model Answer

0 min read

Introduction

The Green Revolution of the mid-20th century dramatically increased food production in India, largely through the adoption of High Yielding Varieties (HYVs) coupled with intensive use of chemical fertilizers, pesticides, and insecticides. While these inputs initially addressed food security concerns, their widespread and often indiscriminate application has raised significant concerns about human health and environmental sustainability. These chemicals, designed to enhance crop yields and protect against pests, pose a complex challenge, demanding a nuanced understanding of their benefits and detrimental effects. The current context necessitates a re-evaluation of agricultural practices to prioritize both productivity and public health.

Use of Chemical Inputs in Agriculture

Chemical fertilizers, primarily nitrogen, phosphorus, and potassium (NPK), are used to supplement soil nutrients and enhance crop growth. Pesticides encompass a broad range of chemicals – herbicides (weed control), insecticides (insect control), and fungicides (fungal disease control). Insecticides, specifically, target insect pests that damage crops.

  • Fertilizers: Urea, diammonium phosphate (DAP), and muriate of potash are commonly used. They increase yield but can lead to nutrient imbalances in soil and water pollution.
  • Pesticides: Organophosphates, carbamates, and pyrethroids are prevalent. They are effective against pests but can have acute and chronic health effects.
  • Insecticides: Neonicotinoids, a relatively newer class, are widely used but linked to bee colony collapse disorder and potential neurodevelopmental effects.

Impact on Human Health

1. Chemical Fertilizers

While not directly toxic in the same way as pesticides, excessive fertilizer use can lead to health problems through several pathways:

  • Nitrate Contamination of Water: Excess nitrates from fertilizers leach into groundwater, contaminating drinking water sources. High nitrate levels in drinking water can cause ‘blue baby syndrome’ (methemoglobinemia) in infants, reducing oxygen-carrying capacity of blood.
  • Food Chain Contamination: Plants absorb nitrates, which can accumulate in edible parts. While generally not acutely toxic, long-term exposure is a concern.
  • Soil Imbalance & Micronutrient Deficiency: Over-reliance on NPK fertilizers can deplete soil of essential micronutrients like zinc and iron, leading to deficiencies in the human population.

2. Pesticides & Insecticides

These pose more direct and acute health risks:

  • Acute Poisoning: Accidental or occupational exposure can cause acute poisoning, leading to symptoms like nausea, vomiting, dizziness, respiratory distress, and even death. This is particularly prevalent among agricultural workers.
  • Chronic Health Effects: Long-term, low-level exposure is linked to:
    • Cancer: Several pesticides are classified as probable or possible carcinogens (e.g., glyphosate).
    • Neurological Disorders: Organophosphates and carbamates can disrupt the nervous system, leading to neurodevelopmental problems in children and neurodegenerative diseases in adults.
    • Endocrine Disruption: Some pesticides mimic hormones, interfering with the endocrine system and potentially causing reproductive problems and developmental abnormalities.
    • Respiratory Problems: Exposure can exacerbate asthma and other respiratory conditions.

Vulnerable Populations

Certain populations are more vulnerable to the health effects of these chemicals:

  • Agricultural Workers: Direct exposure during application and handling.
  • Children: More susceptible to neurodevelopmental effects due to their developing nervous systems.
  • Pregnant Women: Exposure can harm fetal development.
  • Rural Communities: Higher exposure through contaminated water and food.

Mitigation Strategies

  • Integrated Pest Management (IPM): A holistic approach that combines biological control, cultural practices, and judicious use of pesticides.
  • Organic Farming: Eliminates the use of synthetic fertilizers and pesticides.
  • Biofertilizers: Utilizing microorganisms to fix atmospheric nitrogen and solubilize phosphorus, reducing reliance on chemical fertilizers.
  • Promoting Farmer Awareness: Training farmers on safe handling and application techniques, and the importance of personal protective equipment (PPE).
  • Regulation & Monitoring: Strict regulation of pesticide use, monitoring of water and food for chemical residues, and enforcement of safety standards.
  • Promoting Sustainable Agriculture: Crop rotation, intercropping, and conservation tillage can improve soil health and reduce pest infestations.
Chemical Input Primary Health Impact Vulnerable Population
Nitrate Fertilizers Methemoglobinemia (Blue Baby Syndrome) Infants
Organophosphate Pesticides Neurological Disorders, Acute Poisoning Agricultural Workers, Children
Neonicotinoid Insecticides Neurodevelopmental Effects, Bee Colony Collapse Children, Ecosystem

Conclusion

The use of chemical fertilizers, pesticides, and insecticides in agriculture presents a complex trade-off between increased food production and potential harm to human health. While these inputs have played a crucial role in addressing food security, their indiscriminate use has resulted in significant health risks, particularly for vulnerable populations. A shift towards sustainable agricultural practices, including IPM, organic farming, and biofertilizers, coupled with stricter regulation and farmer education, is essential to mitigate these risks and ensure a healthier future. Investing in research and development of safer alternatives is also paramount.

Answer Length

This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.

Additional Resources

Key Definitions

Integrated Pest Management (IPM)
IPM is an ecologically based approach to pest control that utilizes all available control methods – cultural, biological, genetic, and chemical – in a way that minimizes economic, environmental, and health risks.
Bioaccumulation
The gradual accumulation of substances, such as pesticides or heavy metals, in an organism. This occurs when the rate of intake is higher than the rate of metabolism or excretion.

Key Statistics

India is among the largest consumers of pesticides globally, accounting for approximately 15% of the world’s total pesticide use (as of 2020).

Source: FAOSTAT, 2020 (Knowledge Cutoff)

A 2018 study by the Centre for Science and Environment (CSE) found that 70% of vegetables and fruits sold in India contain pesticide residues exceeding permissible limits.

Source: Centre for Science and Environment (CSE), 2018 (Knowledge Cutoff)

Examples

Kerala’s Organic Farming Initiative

Kerala has been actively promoting organic farming, aiming to become a 100% organic state by 2030. This initiative focuses on reducing chemical fertilizer and pesticide use through farmer training, subsidies for organic inputs, and market support for organic produce.

Frequently Asked Questions

Are all pesticides equally harmful?

No, pesticides vary significantly in their toxicity and persistence in the environment. Some are acutely toxic, while others have chronic effects. The risk depends on the chemical’s properties, exposure levels, and individual susceptibility.

Topics Covered

EnvironmentScience & TechnologyEconomyAgriculturePollutionHealthChemicals