Chemical pollution on the space station

International Space Station (ISS). Credits: NASA

a New study Posted in Environmental Science and Technology Letters It reveals that concentrations of some potentially harmful chemicals in dust collected by air filter systems are on International Space Station (cause) exceed those found in floor dust in many homes in the United States and Western Europe. It is the first study of its kind conducted by analyzing a sample of dust from air filters inside the International Space Station.

The researchers participating in the study – whoUniversity of Birminghamin the UK, and del Glenn Research Center From NASA, USA – They say their findings could guide the design and construction of future spacecraft.

Contaminants in “space dust” include polybrominated diphenyl ethers (PBDEs).Pbde), hexabromocyclododecane (Hbcdd), new brominated flame retardants (bfr), organophosphate esters (obi), polycyclic aromatic hydrocarbons (Bah), perfluoroalkyl substances (Pfas) and PCB (PCB).

Bfrs and Opes are used in many countries to meet fire safety regulations in consumer and commercial applications such as electrical and electronic equipment, building insulation, upholstery fabrics, and foams.

Hydrocarbons are found in hydrocarbon fuels and are emitted from combustion processes, PCBs have been used in building sealants, windows and electrical equipment as dielectric fluids, while Pfas have been used in applications such as anti-stain agents for fabrics and clothing. However, their potential effects on human health have led to bans or restrictions on the use of some of them.

PCBs, some Pfas, Hbcdd, and commercial Penta-Octa- and Deca-Bde formulations of Pbde are classified as persistent organic pollutants (POPs) Stockholm Convention from Unep. Moreover, some PAHs are classified as human carcinogens, while some PEUs are restricted by the European Chemicals Agency.

“Our findings have implications for future space stations and forteas it may be possible to exclude many sources of pollutants by carefully selecting materials in the early stages of design and construction,” he comments. Stuart Harrad, from the University of Birmingham, co-author of the study. “While concentrations of organic pollutants detected in ISS dust often exceeded average values ​​found in homes and other indoor environments in the United States and Western Europe, levels of these compounds were generally within the range found on Earth.”

The researchers noted that concentrations of Pbde in the dust sample that are within the range of concentrations found in US household dust may be due to the ISS’ use of inorganic flame retardants such as diammonium dihydrogen phosphate, used in the manufacture of fabrics and fabrics. They believe that commercially available “off-the-shelf” items brought in for the astronauts’ personal use — such as cameras, mp3 players, tablets, medical devices, and clothing — are potential sources of many of the detected chemicals.

The air inside the International Space Station is constantly recirculated at a rate of 8-10 changes per hour. While removal of carbon dioxide and trace gaseous pollutants does occur, the degree of removal of chemicals such as Bfrs is unknown. High levels of ionizing radiation can accelerate the aging of materials, including the decomposition of plastic products into micro and nanoplastics, which become airborne in a microgravity environment. This may be why the concentrations and relative abundances of Pbde, Hbcdd, Nbfr, Ope, Ipa, Pfas and Pcb in ISS dust differ markedly from those in Earth’s inner microenvironment dust.

to know more: