Chemicals from products including household cleaning agents, cosmetics, adhesives and printing inks lead to â€˜substantial emissionsâ€™ of air pollutants, a US study has suggested.
Published in the â€˜Scienceâ€™ journal on Friday (16 February), the study looked at the emission of volatile organic compounds (VOCs) from a range of non-automotive sources.
VOCs are emitted as gases from certain solids or liquids, and can include a variety of chemicals, some of which may have short- and long-term adverse health effects.
According to the study, automotive emissions of VOCs have decreased â€˜steadilyâ€™ in the US and Europe in recent years due to efforts to control tailpipe emissions. As a result, they suggested, â€œother sources of VOC emissions are likely growing in relative importanceâ€.
Researchers looked at a range of products containing organic solvents which lead to emissions of VOCs in the atmosphere, including pesticides, coatings, printing inks, cleaning agents and personal care products.
According to study, current inventories in the US â€˜consistently underestimate total VOC emissions from VCPs â€“ volatile chemical products â€“ by factors of two to three nationally and regionallyâ€™.
â€œThe main effect of our analysis is to shift the relative contribution of VOC emissions from petrochemical sources, away from mobile sources and towards VCP,â€ the study concludes. â€œAt national and urban scales, we attribute 15 to 42% of petrochemical VOCs to mobile sources and 39 to 62% of petrochemical VOCs to VCPs. The rest is from upstream sources associated with oil and natural gas production and distribution.â€
While the study notes that fossil fuels remain a major source of ambient air pollution â€“ emissions from chemical products are likely to be of greater concern in indoor environments. It adds: â€œAlthough fossil fuels remain important sources of urban air pollution, exposure to ambient PM2.5 is increasingly from chemical products as the transportation sector becomes cleaner. Additionally, because a large fraction of VCP emissions occurs in buildings, exposure to air toxics is of concern indoors.â€
The report suggests that while â€˜traditionalâ€™ approaches to mitigating air pollution have focused on transport and industrial sources, chemical products are an emerging source of urban VOCs, which are not declining as fast as those from transport.
â€œNew paradigms leveraging research tools from the indoor and outdoor air quality communities could strengthen efforts to reduce human exposure to O3, PM2.5 and air toxics,â€ researchers noted.