Nanotechnology enabled fertilizer: Salvation for industrial-scale agriculture?

Lake Erie Algae Mega Bloom
Used under creative commons license from noaa glerl

As farmers begin the fall harvest, a downstream result of their use of fertilizer blooms in Lake Erie, 700 square miles of algae, some of it toxic. The Environmental Protection Agency (EPA) lists nitrogen and phosphorus fertilizer overuse as major pollutants, but neither the EPA nor the U.S. Department of Agriculture regulates the application of fertilizer. Indeed, the Trump administration is seeking to repeal the EPA Waters of the United States (WOTUS) rule that would have begun to mandate water quality standards applied to fertilizer overuse and other agricultural sources of pollution. (The novel legal basis for the repeal is not a refutation of the scientific basis for WOTUS, but a claim that a Trump executive order constitutes a policy change for which no scientific justification is needed.) The Fertilizer Institute (TFI), the industry’s research and advocacy organization, supports WOTUS suspension, arguing that its voluntary fertilizer stewardship programs, not “the iron hand of regulation is the clearest and quickest path to success.” 

In this dire agri-environmental situation, TFI held its 2017 “nutrient stewardship summit”, June 12-13 in Minneapolis, which IATP attended. TFI announced an increased enrollment in its voluntary “4R” farmer certification program to reduce fertilizer use while increasing crop yields. Fertilizer chemists reported on their laboratory and field experiments to reduce nitrate runoff from fertilizer and to reduce nitrous oxide emissions, which have a global warming effect about 296 times that of carbon dioxide. One chemist told me that for the first time at a TFI meeting, he heard the words “cover crops” mentioned to not only prevent nitrogen and phosphorus pollution but to reduce fertilizer use.

One word I did not hear, in response to my questions, was “nanotechnology,” even though there is research funded by governments and the fertilizer industry to produce nanotechnology enabled fertilizers. Neither does a word search for “nanotechnology” on the TFI website produce results. Nanotechnology, the visualization, manipulation, manufacture and incorporation of atomic to molecular-sized materials into industrial and consumer products, is a technology proposed to make fertilizer nutrient uptake more efficient and reduced fertilizer application related pollution

Fortuitously, IATP is publishing its report on nanotechnology enabled fertilizers the day before the second Global Fertilizer Day, during which “international agricultural professionals meet to celebrate the key role that fertilizer plays in meeting the growing global demand for nutritious and sustainably grown food.” A “Get Involved” program encourages TFI’s 89,000 members to tweet such messages as “two out of every five people in the world owe their lives to the use of fertilizer” and “farmers today grow a bushel of corn using 45 percent less nitrogen and phosphate than they did in 1980.”

Notwithstanding the Global Fertilizer Day celebrations, the EPA suspension of the WOTUS rule and the agribusiness financed defeat of a Des Moines Water Works lawsuit to force regulation, under the Clean Water Act, of nitrogen fertilizer runoff pollution of Des Moines municipal water—TFI is worried. If the voluntary fertilizer stewardship program, as implemented by TFI, fails to reduce water pollution in Iowa and elsewhere, another municipal waterworks may find a judge willing to apply the Clean Water Act to farm generated pollution. An additional defense against the so-called “iron hand of regulation” is a nanotechnological means to reduce nitrogen pollution in agricultural production.

Nitrogen fertilizer pollution of water and emission of nitrous oxide is not limited, of course, to farms in Iowa, Ohio or elsewhere in the United States. Indeed, IATP’s report on nanotechnology enabled fertilizers reviews reports on laboratory experiments by Brazilian, Canadian, Chinese and Sri Lankan research teams. The reports have in common the objective of improving plant nutrient uptake of nitrogen-based fertilizer and reducing the nitrous oxide emissions and nitrate runoff in agricultural water that occurs when fertilizer nutrients exceed what the plants can use.

Among the research reviewed, there are three approaches to enhancing nutrient uptake and reducing nitrogen related pollution. One approach involves slowing nitrogen release by binding the fertilizer nutrient to Engineered Nanoscale Materials (ENMs), to nano-clays in the case of a Brazilian research team, to nano-rods of Hydroxypatite, a bio-ceramic compound used to provide calcium, phosphate and other minerals in medical applications, in the case of the Sri Lankan research team. The Chinese research team conducted both laboratory experiments and field trials to amend agricultural soils with a nano-clay compound, which when mixed with soil and activated by precipitation, forms nano to microscale structures that retard nitrogen loss. The Canadian research team aspires to develop a DNA based nano-biosensor which, when incorporated into a biopolymer film covering fertilizer micro-nutrients (e.g. copper, iron), will read the electro-chemical signals of plant roots.  Once the nano-biosensor has identified the signal, it causes the biopolymer to become semi-permeable and release a number of nutrients the plant requires at the time they are required.

These approaches to nanotechnology enabled nutrient management each carries different risks, some of which are anticipated by the research teams. For example, the Canadian research team is asking whether the binding of the nano-biosensor in the biopolymer will interfere with the sensor’s ability to accurately read the plant root system signals and release the appropriate amount of fertilizer. If the sensor incorrectly reads or doesn’t read at all the root chemical signals, the plant could receive too much nutrient or too little or none. Another environmental risk yet to be assessed in greenhouse trials is whether the chemical used to modify nano-clays will harm fungi, bacteria and other engineers of soil health.

However, government or private investors in nanotechnology enabled fertilizer expects scientists to deliver a product that will enable the current agribusiness model of mono-cropping for export or domestic production. An expansion of Brazilian corn exports would be greatly aided by a nanotechnology enabled fertilizer that would reduce the costly environmental damage of Brazilian agribusiness’ current trends in fertilizer use.  Under pressure to deliver that product, scientists might downplay the risks to soil health of the chemicals that keep nano-clays from clumping together and thus losing the ENM properties to deliver the promised benefits.

Even if the nanotechnology enabled fertilizers are technically successful and even if their environmental and public health risks are nano small, the fertilizer cartel control over crop input prices is such that the technology might only become economically viable with large taxpayer subsidies from governments that can afford them. As IATP has shown in its recent report on U.S. agribusiness export dumping, except during the years of Wall Street speculation inflated commodity prices, agribusiness pays U.S. farmers at prices below the cost of production. Non-farm jobs and U.S. taxpayer subsidies keep U.S. farm operations afloat and compensate for agribusiness market failure.  

In the U.S., Environmental Quality Incentive Program (EQIP)payments can be used to offset part of the 33 percent extra cost of non-nanotechnology enabled Controlled Release Fertilizer, compared to that of conventional chemical fertilizers. The cost of nanotechnology enabled fertilizers will be higher still and so will the EQIP subsidies for those applying the new fertilizers. However, EQIP payments are not designed to pay for the very large environmental and public health costs of fertilizer water pollution and greenhouse gas emissions.

Without major changes to U.S. agriculture and trade policy, which enable export dumping and abuse of natural resources, the early adopters of nanotechnology enabled fertilizers will again be running on a technology treadmill. This paradigm of agricultural economics shows a pattern of breakdown under low commodity prices, higher new costs of production, subsidies inadequate to cover those costs and the increasing environmental and public health costs that are “externalized” (taken from the balance sheet) by orthodox economists. Nanotechnology cannot fix that economic and policy breakdown.

Read the report Applying Nanotechnology to Fertilizer: Rationales, research, risks and regulatory challenges.