Everyday products such as shampoo, lotions, cleaning products and paint now contribute as much to urban air pollution as emissions from vehicles, say researchers. [Photo: Bigstock]

Consumer products match cars as sources of air pollution

16 February, 2018

Natural Health NewsEveryday products such as shampoo, lotions, cleaning products and paint now contribute as much to urban air pollution as tailpipe emissions from vehicles, according to new US study.

The study, published in the journal Science was led by the National Oceanic and Atmospheric Administration (NOAA), a US government agency that focuses on the conditions of the oceans and the atmosphere, and researchers from the University of California, Davis.

“What’s exciting about this work is that it shows that everyday consumer choices can have an impact on air quality in the US,” said Christopher Cappa, professor of civil and environmental engineering at UC Davis and a co-author on the paper.

The scientists focused on volatile organic compounds (VOCs) that can waft into the atmosphere and react with other substances to produce either ozone or particulate matter – both of which are have known health impacts, including lung damage.

What you need to know

» A new study has shown that even as transportation emissions fall, other oil-based ingredients in everyday products are making an increasing contribution to air pollution.

» Consumer products such as household cleaners, perfumes and lotions can cause high levels of indoor air pollution and, crucially, also contribute to outdoor air pollution.

» Including consumer products in the study, say the researchers, closes a long-standing gap between predictions of what is going into the air and what the data actually shows.

Tiny particles

People use a lot more fuel than they do petroleum-based compounds in chemical products – about 15 times more by weight, say the scientists.

Even so, lotions, paints and other products contribute about as much to air pollution as does the transportation sector. In the case of one type of pollution – tiny particles that can damage people’s lungs – particle-forming emissions from chemical products are about twice as high as those from the transportation sector, the team found.

Transportation is far from off the hook, but over the past few decades, in response to tighter regulations, car manufacturers have made pollution-limiting changes to engines, fuels and gas pumps.

“As transportation gets cleaner, those other sources become more and more important,” said team leader Brian McDonald, a scientist in the Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, working in NOAA’s Chemical Sciences Division.

Personal care products are half the problem

The research team reassessed air pollution sources by sorting through recent chemical production statistics compiled by industries and regulatory agencies, by making detailed atmospheric chemistry measurements in Los Angeles air, and by evaluating indoor air quality measurements made by others.

This led to the conclusion that the amount of VOCs emitted by consumer and industrial products is actually two or three times greater than estimated by current air pollution inventories, which also overestimate vehicular sources.

For example, the Environmental Protection Agency estimates that about 75% of VOC emissions (by weight) come from vehicular sources, and about 25% from chemical products. The new study, which included a detailed assessment of up-to-date chemical use statistics and previously unavailable atmospheric data, puts the split closer to 50-50.

The disproportionate air quality impact of chemical product emissions is partly because of a fundamental difference between those products and fuels.

“Gasoline is stored in closed, hopefully airtight, containers and the VOCs in gasoline are burned for energy,” said NOAA atmospheric scientist Jessica Gilman. “But volatile chemical products used in common solvents and personal care products are literally designed to evaporate. You wear perfume or use scented products so that you or your neighbour can enjoy the aroma. You don’t do this with gasoline,” Gilman said.

Closing the gap

Cappa said that there has been a persistent gap between levels of fine particles measured in urban air and predictions from models. The new work has the potential to close this gap, he said.

The team found that they simply could not reproduce the levels of particles or ozone they measured in the Los Angeles area without including emissions from volatile chemical products. They also determined that people are exposed to very high concentrations of these volatile compounds indoors.