According to a new study, freshwater basins worldwide are seeing significant growth in man-made phosphorus pollution, reaching potentially dangerous levels. The study charted the growth of such pollution from 2002 to 2010.
The likely cause for such an increase is tethered to phosphorus’ widespread inclusion in mineral and manure fertilizers. Because plants do not absorb the entirety of phosphorus content found in these manures, a substantial amount is left over, subsequently building up or washing away to different bodies of water.
Throughout the course of the study, it was found that 1.62 million tons of phosphorus was emitted annually. It was also discovered that humans are emitting phosphorus at a faster rate than the planet can naturally dilute it.
“In many areas of the world either there’s not enough water to assimilate the phosphorus or the pollution load is so huge that the water system can’t assimilate everything,” said Mesfin Mekonnen, a post-doctoral research associate at the University of Nebraska.
The study also broke down total phosphorus contribution by countries and their respective addition to the total amount. China accounted for 30%, India accounted for 8% and the United States contributed 7%.
Such an influx of phosphorus inevitably leads to eutrophication for many of these freshwater basins. Eutrophication occurs when there is an excess level of nutrients in the water, which can then lead to algal blooms, threatening the health of plants and fish.