The picture on the left is a mine and the one on the right is near the outlet of a hotspring.Arsenic concentrations are also high at hotsprings and other geothermal sources. Arsenic is often associated with mineral ores that are mined, like copper, gold and zinc. Put another way, it’s like 2-5 grains of salt in a half cup of sugar, or 2-5 drops of lemonade in a 13 gallon barrel of water.Īrsenic is not evenly distributed though, so some places have much higher arsenic concentrations, and other places are lower.So for every million grams of earth crust, there would be between 2 and 5 grams of As present.It is the 20th most abundant element on Earth. It is found in the Earth’s crust (the solid outer layer that we live on) at a concentration of around 2-5 parts per million. About 100 mg of As is enough to kill a grown person – that’s about 1/20th of a teaspoon!Īrsenic is a naturally occurring compound.Potent means that it has a strong effect even in very low amounts – so a tiny bit of arsenic can do a lot of damage.They somehow stop or change a function that is required for the animal, person or plant to live. Toxic chemicals prevent or affect processes that are required for life. We are mainly interested in arsenic because of its toxicity. Biological molecules are made up mostly of non-metals such as carbon (C), hydrogen (H), oxygen (O), nitrogen (N), sulfur (S), and phosphorus (P), although metals are needed in much lower amounts.Semiconductors are used a lot in the electronics industry. Since these compounds conduct electricity poorly, they are also called semiconductors. Elements that are not very good at conducting electricity but can still do it, and that conduct electricity better at higher temperature fit in between these groups and are called metalloids. Metals are good conductors of electricity, but the conductivity goes down as the temperature goes up.The molecular weight of arsenic is 75, so one mole of As atoms has a mass of 75 grams.Īrsenic is a metalloid, meaning it shares some characteristics with metals, and some with non-metals. In this model, two chains stick together to form a double helix. The orange blobs are the phosphorus atoms that link the nucleotides (individual DNA molecules) together in a long chain. The picture shows a model of the DNA molecule. That means it has 33 protons in its nucleus and 33 electrons buzzing around the nucleus, when it is uncharged. Arsenic can hitch a ride in the cell’s transporter system for P. Elements in the same column usually have similar properties, so arsenic has similarities to phosphorus (P), which is a part of the DNA molecules (see below) that make up your genes – that similarity might explain how it is taken up by cells.Arsenic (As) is an element, which means that it is a chemical that can’t be broken down into simpler chemicals (so it is not a compound or molecule that is made up of other elements).
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