Children’s exposure to home wood-burning could be as significant as traffic exhaust, study suggests

Children’s exposure to home wood-burning could be as significant as exposure to traffic exhaust, suggests new research across six European towns and cities.

Scientists measured the air in buildings where children spend much of their time; in schools, sports centres and homes. Specifically, they looked at polycyclic aromatic hydrocarbons (PAH), a family of pollutants that are given off when fuels are burned.

Dr Barend van Drooge, from Barcelona’s Institute for Environmental Assessment and Water Research (IEAWR) and senior author of the study, said: “Some of these compounds are related to cancers after prolonged exposures, as recognised by the International Agency for Cancer Research, and evidence exists that they delay cognitive development.”

Measurements were made in and around Athens, Barcelona, Colchester, Copenhagen, Helsinki and Lisbon.

Van Drooge continued: “Urban areas with wood-burning, such as Colchester and Athens, had the highest PAHs levels. Barcelona and Lisbon, where wood-burning is not practised, had the lowest levels.”

In Colchester and Athens, PAH exposure was greater than the World Health Organization guidelines.

Maria Antonia Aretaki, of the IEAWR in Barcelona and first author of the study, said: “Understanding the pollutants in children’s everyday surroundings is an important step towards protecting their health. Children are particularly important given their vulnerability to environmental pollutants and the potential health implications from exposure during childhood.”

Sports centres had the lowest concentrations. This was followed by schools, through some, especially those in Lisbon, were affected by nearby busy roads. Ventilation and indoor sources were important, but the homes with some of the greatest PAH were in areas with wood-burning, and many had open fireplaces and stoves.

Winter PAH concentrations were greater than summer.

The researchers divided the PAH into two types, according to molecular weight. In the Colchester homes, the high-molecular-weight PAH in winter were more than 10 times those in summer. The low-molecular-weight PAH were around three times greater.

Van Drooge continued: “Wood-burning is known to be an important emitter of PAH, but it was surprising that it has become such an important contributor to the overall presence of PAHs in urban areas. However, none of the cities exceeded unacceptable limits for lifetime cancer risk.”

Within the UK, the impacts of wood-burning are unlikely to unique to Colchester. Separate analysis of energy performance certificates by researchers at University College London showed that Colchester ranked 120th out of 333 local councils for density of wood burners per square kilometre. Worthing, Norwich and Reading all had around four times more.

A wintertime study of 53 children from two primary schools in Anglesey (Ynys Môn) found that children living in homes with wood burners could be exposed to over three times more particle pollution than those in non-wood-burning homes. The Anglesey study also found that homes had more air pollution than schools.

In Greece, wood-burning increased during the financial crisis that began in 2008. The cost of heating oil soared and many people turned to wood heating. This contributed to increased deaths associated with particle pollution in Athens, especially for those aged over 70. In some Greek towns, wood-burning leads to PAH that are 100 times greater in winter compared with summer.