In an extremely shortsighted view, use of such fertilizer makes sense because plants need nitrogen to grow. As such, crops pull nitrogen out of the soil each season, leaving it depleted after harvest. Traditional agriculture techniques, such as composting crop waste and applying animal manure, naturally help to cycle usable nitrogen back into the soil. But in the early 1900s, a German chemist developed synthetic nitrate, which is the form of nitrogen plants use. Originally, this nitrate was used to make bombs, not fertilizer, but after World War II, its use shifted to agriculture. But this "quick fix" comes at a steep price, as the nitrogen that helps some crops to grow is now causing untold amounts of environmental damage.
The finding brings up grave concerns for the environment, even if nitrogen fertilizers stop being used. Nandita Basu, Ph.D., a water sustainability and ecohydrology expert at the University of Waterloo, told Newsweek...
"The fact that nitrogen is being stored in the soil means it can still be a source of elevated nitrate levels long after fertilizers are no longer being applied."
It is actually pretty simple to understand, when fertilizer is applied to gardens and farm fields, some gets taken up and used by crops, some dissipates into the air and is gone, some gets dissolved in water and runs off, and some gets converted to nitrogen gas by microorganisms.
The excess that becomes part of the organic matter in the soil is not harmful in and of itself. In fact, it makes the soil far more fertile; but over time, when too much fertilizer is repeatedly applied, excess nitrogen is mineralized as nitrate and is stored at depth in the soil which then allows it to leach into the water table. That is harmful and that is the problem.
Excess nitrogen accumulated deep in the soil could continue to leach into groundwater for 35 years after the fertilizer use is ceased. While agricultural runoff is typically exempt from clean water laws, the water utility in Des Moines, Iowa, is currently suing three counties, alleging they polluted the river with nitrates from agricultural runoff, which have been linked to cancer and birth defects, reported the Newsweek article above. If the lawsuit succeeds, the agriculture industry will have to make changes to limit runoff.
It's estimated that in the last four decades, nitrogen fertilizer efficiency has decreased by two-thirds, while their use per hectare (approximately 2.5 acres) of land has increased by seven times. The U.S. Department of Agriculture (USDA) estimates that removing nitrate from U.S. drinking water costs nearly $5 billion a year, which the industrial agriculture industry has been largely shielded from.
The Occupational Safety and Health Administration (OSHA) is attempting to enforce strict chemical management and storage rules for fertilizer retailers, but the Agricultural Retailers Association, Fertilizer Institute, American Farm Bureau Federation and others are fighting back. They are lobbying lawmakers to block OSHA from applying its safety standards, which they say "will place a significant time and cost burden on America's agricultural retailers" and cost up to $30,000 per facility (which, to me, seems a rather small price to pay to save human lives).
The OSHA standards would apply to anhydrous ammonia, which is another type of nitrogen fertilizer that only a few years ago was a major ingredient in meth. The white tanks it is stored in dot farm fields across the U.S., making them prime targets for anyone wanting to siphon off their contents. While today most meth-makers aren’t using anhydrous ammonia, it is still a concern because it is such a volatile chemical. Farmers fear that thieves will forget to shut off a valve, allowing volatile anhydrous ammonia to seep out.
Why is that a problem? Well, chemically, it's the same ammonia used in cleaners around the house, minus the water (thus, it is 'anhydrous'). The vapor is corrosive to human skin and aggressively seeks out water wherever it can find it, which means that anhydrous leaks can result in horrific injuries to the eyes, throat, sinuses, and lungs. See? That’s the problem!
In a report released by environmental group Mighty Earth, massive manure and fertilizer pollution churned out by meat giant Tyson Foods is blamed for causing the largest dead zone on record in the Gulf of Mexico. According to NOAA, the area of low oxygen, which can kill marine life, is 6,000 square miles and growing, which is about the size of New Jersey. Mighty Earth singled out Tyson and another meat giant, Smithfield, as top contributors to the dead zone for several key reasons:
- Tyson produces 1 out of every 5 pounds of meat in the U.S. and is the only company with processing facilities in each of the states contributing the highest levels of pollution to the Gulf of Mexico
- Tyson and Smithfield have the highest concentration of meat facilities in the areas with the highest levels of nitrate contamination
- Tyson's feed suppliers are responsible for the majority of grassland prairie clearance in the U.S., which "dramatically magnifies the impacts of fertilizer pollution"
Then there is the nitrous oxide, a gas said to be 300 times more potent than carbon dioxide as a greenhouse gas and labeled "the world's most significant ozone-depleting substance."
According to the non-profit organization GRAIN:
"The Intergovermental Panel on Climate Change (IPCC) estimates that for every 100 kg of nitrogen fertilizer applied to the soil, one kg ends up in the atmosphere as nitrous oxide (N2O). In 2014, this was equivalent to the average annual emissions of 72 million cars driven in the U.S. or roughly a third of the U.S. fleet of cars and trucks. New research, however, shows that these alarming numbers are at least three to five times too low.”
The use of synthetic nitrogen fertilizers is one of the greatest threats to organic matter in the soil. Despite industry propaganda to the contrary, recent studies demonstrate that chemical fertilizers are responsible for much of the massive loss of organic matter that has occurred in the world's soils since the pre-industrial era.
“In numerous publications spanning more than 100 years and a wide variety of cropping and tillage practices, there is found consistent evidence of an organic carbon decline for fertilized soils throughout the world,” Reported University of Illinois soils scientist Charlie Boast.
Soils around the world have lost, on average, at least 1 to 2 percentage points of organic matter in the top 30 cm since chemical fertilizers began to be used. This may not seem like much at first but consider that this amounts to some 150,000 to 205,000 million tons of organic matter, which has resulted in 220,000 to 330,000 million tons of CO2 emitted into the air or 30 percent of the current excess CO2 in the atmosphere! Now you see the problem. Read more about it here: Mother Jones April 19, 2013.
As if this weren’t enough, the U.S. fertilizer industry also relies heavily on natural gas extracted by hydrofracturing, or fracking, which is the controversial process of extracting gas from rock formations by bombarding them with water spiked with toxic chemicals. And let’s face facts here, if ‘Big Ag’ becomes hooked on cheap fracked gas to meet its fertilizer needs, then the fossil fuel industry will have gained a powerful ally in its effort to steamroll regulation and fight back opposition to fracking projects.
The use of synthetic fertilizers is clearly the next "nitrogen bomb" waiting to drop. Meanwhile, natural, organic, biological farming helps keep the planet healthy by naturally sequestering carbon in the soil and reducing, or eliminating, the need for chemical fertilizers. This includes such methods as cover cropping, which fortunately is on the rise. As regenerative farmer Gabe Brown likes to say, cover crops provide "armor" over the soil.
This armor can virtually eliminate the need for irrigation when done right, but also, it's the cover crops that provide the carbon that becomes that all-important "armor" on the soil surface. Cover crops also act as insulation, so the soil doesn't get as hot or cold as it would if bare. This allows microbes to thrive longer. Also, the soil biology heats up the soil, which can extend your overall growing season in colder areas, and which helps prevent soil erosion.
In 2012, a Census of Agriculture report found just over 10 million acres of farmland (out of 390 million total) were being planted with cover crops, but its use is growing. In an annual survey of farmers taken in 2014, farmers reported planting double the mean acreage in cover crops reported in 2010. Farmers who adopt the technique have reported better soil texture, less erosion, and increased crop yields. This works in your garden too!
National Geographic described a research project in Michigan that has been ongoing for the past two decades. The project is part of Michigan State University’s Kellogg Biological Station, near Kalamazoo. Here, fields that are one hectare (approximately 2.5 acres) in size provide side-by-side comparisons of four different farming methods ranging from conventional to organic.
Everything that is added to or removed from each field is carefully measured, including rainfall, fertilizer, nitrous oxide, water that leaches into groundwater, and the harvest itself. According to the National Geographic May 2013 article:
"Each field planted according to standard plowing and fertilizer recommendations released 610 pounds of nitrogen per acre into Michigan's shallow groundwater over the past 11 years ... The organic fields … which received no commercial fertilizer or manure, lost only a third as much — but those fields also produced 20 percent less grain.
Intriguingly, the 'low input' fields, which received small amounts of fertilizer but were also planted with winter cover crops, offered the best of both worlds: Average yields were about as high as those from the conventional fields, but nitrogen leaching was much reduced, almost to the level of the organic fields.
If America's farmers could cut their nitrogen losses to something close to this level... restored wetlands and revived small streams could clean up the rest … though, many farmers find it hard to change."
Fertilizer companies claim their products are necessary to feed the world, but research suggests working with nature instead of against it via agroecology or "ecological farming" can produce as much food without the need for chemical fertilizers.
The elimination of chemical fertilizers is one of the easiest and most effective places to start. Cutting out chemical fertilizers could reduce annual global greenhouse emissions by as much as 10 percent. Additionally, the shift from chemical fertilizers to agroecological practices would allow farmers to rebuild organic matter in the world's soils, and thus capture a possible two- thirds of the current excess CO2 in the atmosphere within 50 years.
Each of us can do our part too. On an individual level you can help by buying food from farmers who are using natural methods and soil-regenerative techniques, such as no-till, cover crops, composting and livestock integration. You can even grow our own garden using organic methods. This will naturally help you to eat better too, since typically only real whole foods are grown this way (while most processed foods are the product of destructive industrial nitrogen-fertilizer-laden agriculture).