The Impact of Human Activities on the Global Salt Cycle: A Threat to the Environment and Human Health

We know, that die Demand for salt with costs to the environment and human health connected is. Global production of various types of salt has increased rapidly over the last century. About 300 megatons of sodium chloride (NaCl), known as table salt, are produced each year.

According to Review-Studiewhich recently appeared in the magazine Nature Reviews Earth & Environment was published, and by Sujay Kaushal, Professor of Geology at the University of Maryland in the United States, shows that Human intervention is making the air, soil and fresh water saltierwhich could threaten life on the planet in the future.

How do human activities affect the salt cycle?

The researchers analyzed information about the diversity of the Salt ions in the subsoil and in surface waters and estimate that human-caused soil salinization (overaccumulation of mineral salts) has affected approximately 1 billion hectares of soil worldwide – an area the size of the United States.

The “anthropogenic salt cycle” is characterized by the accelerated transport of salts to the Earth’s surface through mining and raw material extraction, increased salt fluxes into the atmosphere through saline dust, and increased soil salinization and evaporite formation due to desiccation.

According to the article, anthropogenic activities have accelerated the processes, time scales and magnitudes of salt flows and changed their direction, creating the so-called “anthropogenic salt cycle.” These human activities include Miningland development, Agriculturewater treatment and road construction as well as others industrial activities. In extreme situations, this can even mean that drinking water is no longer drinkable for people and animals.

“When people think of salt, they typically think of sodium chloride, but our work over the years has shown that we other types of salts disrupt, including those associated with limestone, gypsum and calcium sulfate,” said Kaushal.

Research also shows that the amount of salt ions in streams and rivers has increased over the past 50 years, coinciding with an increase in global use and production of salts. And that’s not all. Also the Air has become saltier; in some regions of the world they dry Lakes and send clouds of salty dust into the atmosphere.

This Salt dust can accelerate snowmelt and harm communities – particularly in the western United States – that rely on snow for their water supply. Because of their structure, salt ions can combine with pollutants in soils and sediments, forming “chemical cocktails” that circulate in the environment and cause harmful effects.

Worrying…

Just as there are measures to reduce carbon dioxide (CO₂) emissions into the atmosphere to mitigate the effects of climate change, the authors call for to set limits for the safe and sustainable use of salt on our planet.

Soils impacted by anthropogenic salinization (areas shaded in red) in 2016, highly saline. Source: Kaushal et al.(2023).This excess salt leads to the salinization of fresh water exceeding fresh water reserves and food and energy production, air quality, human health and infrastructure are affected.

“This is a very complex issue because salt is not considered a major contaminant of drinking water in the United States, so regulating it would be a major undertaking. But I believe it is a substance that is present in the environment at harmful levels occurs,” says Kaushal.