The Effects of Synthetic Fertilizers

by Natasha Gilani
    Synthetic fertilizers increase crop yield but also have numerous harmful effects.

    Synthetic fertilizers increase crop yield but also have numerous harmful effects.

    Agriculture has relied on the use of natural fertilizers -- substances that increase the nutrient levels of soil -- for most of human history. Synthetic fertilizers made an entrance at the end of the 19th century and paved the way for modern agricultural production. Their use increased crop yields and brought on an agricultural revolution, the likes of which the world had not seen before. Synthetic fertilizers continue to have far-reaching effects, both positive and negative, and are likely to remain a part of human life for some time to come.

    Organic vs. Synthetic Fertilizers

    Fertilizers are of two types: organic, or natural, and inorganic, or synthetic. Organic fertilizers are naturally occurring substances and include biofertilizers, green manure, organic manure and compost. They slowly leach essential nutrients into the soil and improve its overall vitality with time. Synthetic fertilizers are man-made combinations of chemicals and inorganic substances. They typically combine nitrogen, phosphorus, potassium, calcium, magnesium and other elements in different ratios. Synthetic fertilizers, unlike their organic counterparts, immediately supply essential nutrients to soil.

    Positive Effects of Synthetic Fertilizers

    Synthetic fertilizers supply consistent amounts of precise nutrients to the soil. They act on soil immediately -- unlike organic fertilizers that need to break down before absorption. This immediate efficacy is especially beneficial to dying or severely malnourished plants. Synthetic fertilizers are easy to use and their effects are almost immediate. Synthetic fertilizers are convenient to use and easily available in gardening stores.

    Negative Effects of Synthetic Fertilizers

    Synthetic fertilizers have long-term negative effects. Synthetic fertilizers kill beneficial microorganisms in the soil that convert dead human and plant remains into nutrient-rich organic matter. Nitrogen- and phosphate-based synthetic fertilizers leach into groundwater and increase its toxicity, causing water pollution. Fertilizers that leach into streams, rivers, lakes and other bodies of water disrupt aquatic ecosystems. Synthetic fertilizers increase the nitrate levels of soil. Plants produced from such soil, upon consumption, convert to toxic nitrites in the intestines. These harmful nitrites react with the hemoglobin in the blood stream to cause methaeglobinaemia, which damages the vascular and respiratory systems, causing suffocation and even death in extreme cases (when blood methaemoglobin level is 80 percent or more). Synthetic fertilizers damage the natural makeup of soil in the long term. Plants that grow in overly fertilized soil are deficient in iron, zinc, carotene, vitamin C, copper and protein.

    Minimizing Negative Effects

    Mix synthetic fertilizer well into the soil. This will prevent runoff when it rains. Dilute your water-soluble synthetic fertilizer well before use. Improperly diluted fertilizer can burn your plants. Wash all vegetables and fruit yield from synthetically treated soil thoroughly before eating. Keep unused fertilizer away from water, pets and children. Consider switching to organic fertilizers, which are safer and cause no pollution.

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