14 DAY TRIAL // Water pollution is one of the most notorious man-made threats, as scientists have reached the conclusion that the Thames River, the main source of drinking water for millions of people, reflects a high level of nitrate pollution.
Nitrate contamination is the effect of agricultural techniques involving fertilizers. Even though they count as effective methods of preserving the balance of the food security system, they also affect water quality and expose residents to potential health risks.
Experts have taken into consideration water quality measurements performed during the last 140 years, the Environmental News Network informs.
After analyzing the data, researchers have reached the conclusion that nitrate concentrations found in the water of the Thames River have significantly grown during and after World War II and have preserved the same path even after the 1970s.
What seems to be troubling scientists is that nitrate levels have remained constant, even though the agricultural sector has experienced a decline over the last three decades.
Scientists suggest that the nitrate rapid growth witnessed until 1972 is correlated with plowing of permanent grasslands, occurred during the World War II.
"Our results suggest it could take several decades for any reduction in nitrate concentrations of river water and groundwater, following significant change in land management practices," reveals Dr. Nicholas Howden, senior lecturer in water in the Department of Civil Engineering and one of the authors of this study.
At this point in time, the members of the team focus all their efforts to tackle the nitrate contamination issue.
However, they suggest that this is a long-term strategy that requires a lot of support and effective changes in the agricultural sector to come up with traceable results.
They also highlight that if the same path is preserved and groundwater nitrate levels remain constant or keep growing, the situation would worsen and trigger even more alarming effects, decreasing water quality.
"The 60s and 70s saw a gradual intensification of food crop production and consequent nitrate release from the land. If your input is dispersed, your output is dispersed; if your input is sharp, your output is sharp. The aquifer is just transporting it; it’s not processing it. The nitrate comes through as a pulse," notes Dr. Fred Worrall, the co-author of this study.