Tetanus vaccine can help prevent tetanus disease, commonly known as lockjaw.. Tetanus is a serious disease that causes painful tightening of the muscles, usually all over the body. It can lead to locking of the jaw so the person cannot open his mouth or swallow. Tetanus leads to death in about one in ten cases.
The most abundant dissolved salt in ocean water is sodium chloride. It is a colorless crystalline compound with the chemical formula of NaCl.
It has roughly 2/3 the salt content of regular seawater. Ocean salinity (expressed in  - per mil) is approximately equal to the weight, in grams, of salts dissolved in 1000g of seawater. This would be the salt concentration in parts-per-thousand (). Average ocean water has a salinity of 35g of dissolved salts.