These are the people you can smell long before you actually see them.
Some of us won't mind their scent and will have no trouble sitting next to them in a meeting. Others will find their fragrance overpowering, but feel fine once they get some 'fresh air'.
But a small proportion of people may leave the meeting feeling unwell, and in some cases, so ill they will need to head home to bed.
For these people, exposure to some of the chemicals in fragrances can cause asthma, skin rashes, hay fever, migraine, nausea and a range of other unpleasant symptoms.