Phosphorus: The Two-Faced Environmental Menace yet Critical Resource
Many of us have experienced stumbling across a quietly flowing river or slowly rippling lake that looks serene and untouched from afar, but upon closer inspection does not look nearly as enticing. Even to the naked eye, the water is cloudy and green, clearly not safe to drink and not even desirable to swim in. In extreme cases, there is a foul smell emanating from the water recognizable as rotten eggs – sulfur. This phenomenon is most likely an unsatisfactory byproduct of excess nutrients unloaded from human activity in the area.
The usual suspects are Nitrogen (N) and Phosphorus (P) which encourage the growth of cyanobacteria in the water, producing the greenish color we see. Unfortunately, as these bacteria use up the dissolved oxygen, they overcrowd other beneficial organisms in the water and even shade out plant life. Low dissolved oxygen levels can cause large amounts of fish to die off, hurting local fisheries as well as causing an unsightly persistent mess.
Excess nutrients in our waterways cause billions of dollars of environmental damage each year worldwide rendering lakes and streams unusable. In the UK the unsolved problem of river pollution from excess nutrients is delaying the construction of thousands of houses until the existing damage is remediated and future pollution is mitigated1.
What is Needed for Change?
Now, what can be done to prevent this and where should funding be directed when we tackle this problem? Numerous long-term studies of lake ecosystems in Europe and North America have shown that controlling algal blooms depends on reducing inputs of a single nutrient: phosphorus2. They noted that algal blooms did not respond until phosphorus levels decreased below some threshold value as opposed to nitrogen, which does not follow such a trend unless P is reduced with it.
There is another side to phosphorus that must not be ignored. It is an essential nutrient required for crop and livestock production among other industries. The global reserves of phosphate, the naturally occurring form of P, from which fertilizers are derived are a finite critical resource. Phosphorus cannot be made in a lab and many countries have no reserves of their own. Only four countries control approximately 70 percent of the annual global production of phosphate rock from which P is extracted3. The worldwide agricultural market is therefore entirely dependent on the supply chain for fertilizers, feeds, and foods, which are becoming increasingly volatile in cost.
Unlike a murky blue-green algae bloom, the future is clear: we must find ways to capture P before it reaches our lakes, rivers, and water resources, but why should such a valuable resource be considered only an environmental problem? There is a huge opportunity to capture it and reuse it. Recycling this P is our best bet to sustainably meet the future needs of a growing world with a depleting source of naturally occurring phosphorus.
Is Recycling Phosphorus the Way to Go?
The “Our Phosphorus Future” report was written by a team of 40 international experts from 17 countries led by the UK Centre for Ecology & Hydrology (UKCEH) and the University of Edinburgh, and supported by the United Nations Environment Program (UNEP), and it is the most comprehensive global analysis of the challenges and possible solutions to the phosphorus crisis to date. This report estimates an annual yearly clean up cost of environmental damage caused by P to be over $300 Billion worldwide4. The report calls on governments across the world to adopt a “50/50/50” goal: a 50 percent reduction in global pollution of phosphorus and a 50 percent increase in recycling of the nutrient by the year 2050.
However, emerging technologies are advancing with crucial solutions to target phosphorus, especially at its source; hoping to capture it before it reaches our water resources. We can no longer think of this as simply an environmental menace that requires removal. Instead, we must find ways to recycle this increasingly valuable resource to meet future needs.
By: Eli Bergman, CTO of NanoClear Water Solutions
1Davies, Wyre. “River pollution: New phosphate rules hit thousands of planned new homes.” BBC, 24 Oct. 2022, www.bbc.com/news/uk-wales-63285821.
2 Reducing Phosphorus to Curb Lake Eutrophication is a Success
David W. Schindler, Stephen R. Carpenter, Steven C. Chapra, Robert E. Hecky, and Diane M. Orihel
Environmental Science & Technology 2016 50 (17), 8923-8929
DOI: 10.1021/acs.est.6b02204
3 UK Centre for Ecology and Hydrology. “Scientists offer solutions to global phosphorus crisis that threatens food and water security.” Phys.org, 9 June 2022, phys.org/news/2022-06-scientists-solutions-global-phosphorus-crisis.html.
4Lyon, Christopher. “Phosphorus: the Hidden Bedrock of the UK Food System.” Global Food Security, 30 Nov. 2018, www.foodsecurity.ac.uk/blog/phosphorus-the-hidden-bedrock-of-the-uk-food-system/.
5 RePhoKUs. wp.lancs.ac.uk/rephokus/.