The smell of sulfur is usually associated with hydrogen sulfide gas, also known as “sewer gas” (owing to the fact that it is often produced as a byproduct during the breaking down of waste). At low concentrations, this gas is known to have an unpleasant odour that is similar to the smell of rotten eggs. However, it is important to note that at high concentrations, this gas can lead to nausea and even be fatal.
