The International Space Station may be more polluted than most American homes

A new study finds that concentrations of toxic pollutants in dust on the International Space Station (ISS) are greater than those found in Earth dust in many American homes.

Levels of organic pollutants in dust samples from the International Space Station’s air filters were higher than average values ​​found in homes in the United States and Western Europe, according to the study published Tuesday in the journal Nature. Environmental Science and Technology Letters.

“Our findings have implications for space stations and future habitats, as it may be possible to exclude many sources of pollutants by carefully selecting materials in the early stages of design and construction,” said co-author Stuart Harrad, professor of environmental chemistry at the University of Michigan. Birmingham, said V.I a permit.

Contaminants identified in the so-called “space dust” included polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), “new” brominated flame retardants (BFRs), organophosphate esters (OPEs), and polyaromatic hydrocarbons. loops (PAH). Polyfluoroalkyl materials (PFAS) and polychlorinated biphenyls (PCBs).

The authors noted that some commercially manufactured PBDEs are classified as POPs under the UNEP Stockholm Convention, as are PCBs, some PFAS and HBCDD.

Meanwhile, some PAHs have been classified as carcinogens to humans, and some PEUs are under consideration for ECA restriction.

The researchers explain that brominated flame retardants (BFRs) and OPEs (OPEs) are used in many countries to meet fire safety regulations in applications such as electrical equipment, building insulation, furniture fabrics and foams.

PAHs are emitted in combustion processes associated with hydrocarbon fuels, while PCBs are used in building and window sealants and in electrical equipment.

PFAS, also known as the “forever chemicals,” are major ingredients in certain types of firefighting foams, as well as in many consumer products, such as non-stick pans, waterproof clothing, and cosmetics.

The authors hypothesized that the presence of PBDEs in the ISS dust samples could be caused by inorganic fire retardants, which are used to prevent fabrics and webbing from igniting.

The scientists noted that the International Space Station has “a unique internal environment inhabited by humans for more than 20 years since its launch in November 1998.” They explained that the spacecraft’s exposure to fire means that “extreme attention is paid to the flammability of the contents of the International Space Station.”

According to the study, the air inside the International Space Station is constantly being recycled, with 8 to 10 changes per hour. While the system eliminates carbon dioxide and gaseous pollutants, it is unknown to what extent it can remove chemicals such as flame retardants.

In addition to fire retardants, the researchers also identified “off-the-shelf” items on board—such as cameras, MP3 players, tablets, medical devices, and clothing—as potential sources of many of the chemicals they discovered.

Although levels of these pollutants exceeded those of many homes in the United States and Western Europe, Harrad asserted that concentrations of these chemicals “were generally within the range found on Earth.”

However, Harrad and his colleagues are hopeful that their findings can be an asset as policymakers plan for a future that increasingly extends beyond Earth’s borders.

“The findings have implications for future space stations and habitats, as it may be possible to exclude many sources of pollutants through careful material selections in the early stages of design and construction,” they concluded.