Virtual water. Virtual water trade (also known as trade in embedded or embodied water) refers to the hidden flow of water if food or other commodities are traded from one place to another. For instance, it takes 1,340 cubic meters of water (based on the world average) to produce one metric tonne of wheat.
At the same time, researchers also say poor understanding of truly dangerous spider bites delays treatment when a person really has been bitten by a dangerous spider. For example, the bite of the brown recluse spider can cause death of a sizeable area of skin (skin necrosis) resulting in a deep, scarring ulcer. Yet even in areas infested with brown recluse spiders, true bites are uncommon. The analysis is published in the July 14 online issue of The Lancet.
Allergic reactions to spider bites include swelling, anaphylaxis, a lightheaded or dazed feeling, hives or itchiness and diarrhea or stomach cramps. A swelling may occur in the lips, eyes, cheeks and even your feet after a spider bite.