Plants need a variety of nutrients to survive. The three nutrients that plants need the most and that are the most depleted from the soil are nitrogen, phosphorus and potassium. As these nutrients become depleted, fertilisers are often used to replace the lost nutrients. However, excessive use of these fertilisers can have negative effects on the soil and on human health.
Nitrate is a chemical that is poisonous to humans if it seeps into the soil in large quantities, according to ScienceClarified.com. Many fertilisers sprayed through the air can be drifted by the wind. This can cause birth defects, according to TheFertilizerGuide.com.
Efforts have been taken to develop all-natural chemicals that will not harm humans or the environment, according to ScienceClarified.com. However, these all-natural chemicals are more expensive.
Farm workers who apply pesticides have a higher rate of cancers than do those who don't apply pesticides frequently.
Consumer Health Effects
Many farmers use sewage effluent as a fertiliser. This sewage effluent can spread infectious diseases among the farm workers and also can make the consumers of these crops sick, especially when the foods are eaten raw. Many fertilisers also can increase the numbers of inorganic salts, according to TheFertilizerGuide.com. These increased numbers can make the consumers of these plants sick. Fertilisers that contain heavy metals can cause heavy metal poisoning and cancer.
Effects on Plants
Humans can have their food sources increased or reduced depending on how much fertiliser is used, according to the Fertilizer Guide. The appropriate fertiliser can allow plants to grow rapidly. But too much fertiliser can lead to fertiliser burn, which can cause the plants to lose their roots.
Natural Resource Depletion
The production of ammonia, used to create nitrogen fertilisers, accounts for 2 per cent of all the energy consumption in the world. The phosphorus that plants need put in their fertiliser comes from nonrenewable sources and can run out, according to TheFertilizerGuide.com. The phosphorus itself tends to be carcinogenic, with humans living nearby the phosphorus production facilities developing a higher rate of cancers.
Soil exposed to a lot of fertiliser tends to become more acidic. This is great if the soil is very alkaline, but can be bad if the soil was acidic to begin with, according to TheFertilizerGuide.com. Fortunately, lime can be used to increase the alkalinity of soil.
Plants might struggle over time as they deplete the trace nutrients in the soil. These trace nutrients are mostly not replaced by the fertilisers, according to EcoChem.com. The fertilisers allow plants to be grown in soils that normally would not be able to sustain plant growth, so the trace minerals become depleted further.