It\u2019s redundant to say that water is a necessary good for every living creature on this planet. And for mankind it\u2019s even more important, because we use it to produce food, goods, energy, feed animals we breed and for many other purposes. We take it mostly from underground reservoirs, but we can count also on superficial land water bodies, rainfall, and oceans. Marine and freshwater ecosystems have many vital functions: filtering, diluting and storing water, preventing floods, maintaining the climate balance at local and global levels, and safeguarding biological diversity of course.
\nGlobal freshwater and marine resources may seem limitless, but they are under increasing pressure from pollution, over-exploitation and climate change, and this poses the need of avoiding any waste of water.
\nJust to have an idea, nowadays the water consumption of a random citizen in Western countries is on average 500 l\/day for personal uses (washing, drinking, cooking…) and other industrial purposes (energy production and distribution, pharmaceutical products…). Adding daily usage goods, the sum raises till 700-800 l\/day, but what burdens the most on the budget is the production of food. Adding agriculture and livestock products, the water consumption per head achieves a range of 1500-3000 l\/day.
\nThe so called \u201cvirtual water\u201d or \u201cwater footprint\u201d of a product is the esteemed amount of water it took to be produced, calculated by adding up all of the water required for each step of the production process. Some example? 185 l for a bag of crisps, 2400 l for a hamburger, 5400 l for a pair of jeans, and even 450000 l for a car (by the way, I can suggest some interesting virtual water calculators websites\/apps such as www.watercalculator.org or virtualwater.eu). As to economic activities, if we check out the situation just in Europe, on average around 243000 cubic hectometres of water are consumed annually. But the worst aspect is that most of this water often returns directly to the environment with impurities or pollutants, including \u201chazardous substances\u201d \u2013 heavy metals, industrial chemicals, pharmaceuticals, and others. Rivers, lakes and wetlands, as well as seas and oceans, suffer from excess nutrients and altered habitats. Chemical pollution negatively affects both freshwater and marine environments. An example is the eutrophication of lakes and oceans due to the excess of nitrogen and phosphor remains coming mostly from agriculture fertilizers and industrial processes.
\nAnother iconic case is the mercury pollution of oceans. Many people still associate mercury with thermometers and most also know that it is toxic. Actually mercury occurs naturally in the environment, but it is generally safely contained in minerals and does not present any significant risk. The problem is the large amount of biological available mercury released into the environment by human activities. It can easily be taken up by animals, thus finding its way into the human food chain, especially through seafood. Indeed, when marine animals take in mercury, it tends to stay in their bodies and builds up over time. As a consequence, larger predator fishes, such as tuna or swordfish, tend to have higher concentrations of mercury as they consume smaller animals that already have taken up some mercury, a phenomenon known as \u201cbiomagnification\u201d. Moreover, even if mercury is on its way out of European products, the amount already present in air, water and soil \u2013 the current levels of mercury in the atmosphere are up to 500 % above natural levels, while in oceans about 200 % \u2013 can circulate freely for thousands of years… The main sources are industrial and household burning processes of solid fuels \u2014 such as coal, lignite, peat and wood \u2014 and, at a global level, industrial activities and small-scale gold mining (representing more than one third of the global air concentration). However individuals may easily come across mercury containing equipment, such as batteries, lamps and electrical equipment. To make sure that we dispose of these materials properly (so that the mercury they contain can be safely recovered and does not end up in the environment) is a good way to reduce emissions and exposure too. Also preferring available alternatives to burning solids fuels for home heating is a way.
\nWater means life, health, food, leisure, energy and more. Take care of it means take care of us.<\/p>\n