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Tuesday 18 December 2007

RAPID ROUNDUP

Second-hand tobacco smoke increases children's allergy risk

Passive smoking has been associated with lung cancer and heart disease and is the main reason for smoking bans in workplaces and indoor public places, including restaurants, bars and night clubs. This new study, published today in Thorax, looks at the role passive smoking might also play in causing food and environmental allergies. With allergies already costing Australia more than 7 billion dollars annually and with many allergies on the increase, finding a link to passive smoking could be an important preventative step.

Feel free to use these quotes in your stories. If you need assistance tracking down an expert in this area, contact the AusSMC on 08 8207 7415 or email us.

Associate Professor Karen Waters is Research Leader of Paediatric Sleep Team at the Woolcock Institute of Medical Research, University of Sydney

“There is no doubt that exposing a child to cigarette smoke, whether it is during the pregnancy or afterwards, has negative health consequences for that child. Infants exposed to cigarette smoke are more likely to die from sudden infant death and children develop bronchitis and wheezing illnesses. Unfortunately, smoking is also more common amongst parents with less education and who live in poorer social circumstances.

This large Swedish study provides new evidence that children growing up in an environment with cigarette smoke are more likely to become allergic to pets and household allergens including foods. The association demonstrated between parents’ smoking and childrens’ illnesses is so strong that it occurs even when parents do not smoke in the house or around their children. Parental smoking can certainly make children sick.”

Associate Professor Peter Smith is a paediatric allergy specialist in Queensland

"This large Swedish study confirms a doubling of risk of developing allergies to inhalant allergies in the children of smokers. We have long known that environmental pollution increases the risk of developing allergies in the environment. This was first published in 1973 when Charles Blackley reported that allergic rhinitis was linked to urbanisation and industrialisation. This Swedish report suggests that smoking increases the pollution in the immediate environment and the developing child is most at risk. Irritation of the airways with chemicals from smoking may make allow more allergens to pass into the body or alter the way they are processed, however the exact mechanisms of this need to be determined. This paper also has found the smoking increases the risk of child developing allergic antibodies to foods. The study does not correlate antibodies and the presence of disease -so more work is required her. The relation between smoking and possible food allergy is a new finding and one that will be looked at in many further studies.

Overall, this is study reinforces some of the effects of passive smoking, with the most vulnerable being at most risk. Smoking has consequences that reach beyond the well established self-harm."

Dr Raymond J Mullins is President elect of the Australasian Society for Clinical Immunology and Allergy (ASCIA)

“This study adds interesting information regarding the adverse effects of environmental tobacco smoke, suggesting that exposure increases the risk of children developing a measurable immune (“allergic” IgE) response to environmental triggers such as pets, grasses, tree pollens and dust mite. The authors postulate that environment or pollution may have an adjuvant effect to increase the risk of sensitisation. Previous studies have found that exposure to environmental tobacco smoke increases the risk of wheezing in young children, but not an increased risk of sensitisation to environmental allergens. Interestingly, a measurable immune response was also observed to some foods (eg. peanut, egg wheat, soy and cows milk), the first study to link environmental tobacco smoke with sensitisation to food.

Unfortunately, the study poses more questions than it answers. Even though children were followed through to the age of four years, no information is given about the correlation between a detectable immune response as measured by blood testing, and the development of clinical disease. This is unfortunate, as it is highly likely that children allergic to common food triggers such as those listed above, would have manifested their disease well before the age of four years. When it comes to food allergy, low levels of IgE are not uncommon in young children and do not always translate into food allergy, particularly when looking at very low levels of IgE less than the cut-off level of 0.35 kU/ml of specific IgE used in the study. The trend between the intensity of exposure of environmental tobacco smoke and elevation of allergen specific IgE is of interest, but does not appear to be statistically significant for any one environmental trigger other than for sensitisation to cat. Overall, this is an interesting study but its findings are difficult to interpret.”