Home fragrances, usually in the form of air fresheners and scented candles can trigger allergy symptoms or exacerbate existing allergies and cause more severe asthma attacks, according to a study presented at the annual scientific meeting of the American College of Allergy, Asthma and Immunology (ACAAI), Boston, USA. ACAAI president-elect, Stanley Fineman, MD, said that while the sales of scented candles and air fresheners for the home have been rising, so has the respiratory problem rate in homes where these products are used.

Dr. Fineman said:

"This is a much bigger problem than people realize. About 20 percent of the population and 34 percent of people with asthma report health problems from air fresheners. We know air freshener fragrances can trigger allergy symptoms, aggravate existing allergies and worsen asthma."

They may smell as fresh as country woodland, but many home fragrances contain VOCs - volatile organic compounds - which "mask" rather than remove home odors.

The most common VOCs found in air fresheners include:
  • Alcohols
  • Esters - formed by condensing an acid with an alcohol. Commonly used for fragrances.
  • Formaldehyde - the National Toxicology Program (USA) described formaldehyde as "known to be a human carcinogen." (10th June, 2011). The textile industry uses formaldehyde-based resins to make fabrics crease-resistant. Derivatives are used to manufacture cars, and also to make components for electrical systems, engine blocks, door panels, brake shoes, and axles.
  • Limonene - this colorless liquid hydrocarbon has a strong smell of oranges. It is classed as a cyclic terpene. It is used as a precursor to carvone. It is being used increasingly as a solvent for cleaning purposes, e.g. removing oil from machine parts.
  • Petroleum Distillates
Even below recommended acceptable levels of VOC can trigger asthma symptoms in children. At higher VOC concentrations, humans can experience dizziness, headaches, irritation of the respiratory tract, eye irritation, and even memory problems, Dr. Fineman explained.

A recent study found that plug-in deodorizers have over 20 VOCs, one third of which were classed as hazardous or toxic.

Some air fresheners have hazardous or toxic levels of VOCs, according to federal guidelines. However, home fragrance sales continue growing relentlessly. The global market for 2015 is expected to reach $8.3 billion.

Dr. Fineman said:

"There has been a shift among home fragrance consumers that pleasant smelling homes are not just for the holidays. We also are seeing a trend by manufacturers to market these products as aromatherapy which implies health and mood-boosting benefits although there are no scientific studies to support these claims.

For consumers who desire a fresh scent without the associated health risks, Dr. Fineman recommends opening windows to let in Mother Nature rather than selecting products labeled "organic" or "green".

Products marketed as 'all-natural' or even those that are unscented can emit hazardous chemicals. The safest option is to avoid exposure to pollutants that air fresheners emit."

Dr. Fineman says the following people need to become more aware:
  • Consumers - shoppers need to check out carefully what they are bringing into their homes
  • Health care professionals - doctors and specialists (allergists) need to "keep this potential trigger on their radar". Doctors should ask their patients whether they have been exposed to scented products.
In 2008, Anne Steinemann, a University of Washington professor of civil and environmental engineering tested air fresheners and laundry products. (Link to article)

Steinemann said:

"I was surprised by both the number and the potential toxicity of the chemicals that were found."

Several toxic chemicals were identified, including acetone, an active ingredient used in nail-polish remover and paint thinner.

Steinemann continued:

"Nearly 100 volatile organic compounds were emitted from these six products, and none were listed on any product label. Plus, five of the six products emitted one or more carcinogenic 'hazardous air pollutants,' which are considered by the Environmental Protection Agency to have no safe exposure level."

A 2006 study carried out by Environmental Health Sciences (NIEHS), a part of the National Institutes of Health found that a chemical used in air fresheners reduced lung function. (Link to article)

Written by Christian Nordqvist