Respiratory Effects
There are over 17 million asthmatics in the US, 35 million people have chronic sinus infections, and millions more suffer from other respiratory conditions. Most of these problems are exacerbated by the presence of irritants in the air. Fragrances are respiratory irritants. Virtually all organizations that are concerned with respiratory health list fragrances as triggers.

Fragrances contribute to indoor air pollution.

Recently, at the AAAAI conference the results of a study were announced in which many popular perfumes triggered asthma attacks.

Other studies have also shown perfumes to be triggers for asthma and a recent German case study documents occupational asthma caused by exposure to perfumes. (No abstract available on Medline)

Neurological Effects
Fragrances are also known triggers for headaches and migraines. They can also have sedative effects. In a study with mice, exposure to some fragrance chemicals caused a 30-40% decrease in motility.

In one study fragrance chemicals acted on receptors in the brain in a similar manner as alcohol and tobacco effecting mood and function.

Olfactory pathways provide a direct route to the brain for toxic substances. Some fragrance materials can be toxic to the nervous system.

Reproductive Concerns
Citral is a common fragrance material. It is known to cause enlargement of the prostate gland (animal studies). It and other fragrance materials have been found to have estrogenic properties.