Chemical contamination on International Space Station is out of this world, study shows

Concentrations of doubtless dangerous chemical compounds in dust collected from air filtration techniques on the Worldwide Area Station (ISS) exceed these present in flooring dust from many American properties, a brand new examine reveals.

Within the first examine of its sort, scientists analyzed a pattern of dust from air filters inside the ISS and located ranges of natural contaminants which have been larger than the median values present in US and Western European properties.

Publishing their leads to Environmental Science & Expertise Letters, researchers from the College of Birmingham, UK, in addition to the NASA Glenn Analysis Middle, U.S., say their findings may information the design and development of future spacecraft.

Contaminants discovered within the “space dust” included polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), “novel” brominated flame retardants (BFRs), organophosphate esters (OPEs), polycyclic aromatic hydrocarbons (PAH), perfluoroalkyl substances (PFAS), and polychlorinated biphenyls (PCBs).

BFRs and OPEs are utilized in many nations to fulfill fireplace security laws in shopper and commercial applications like electrical and electronic equipment, constructing insulation, furnishings materials and foams.

PAH are current in hydrocarbon fuels and emitted from combustion processes, PCBs have been utilized in constructing and window sealants and in electrical gear as dielectric fluids, whereas PFAS have been utilized in functions like stain proofing brokers for materials and clothes. Nevertheless, their potential human well being results have led to a few of them being banned or restricted in use.

PCBs, some PFAS, HBCDD and the Penta- Octa-, and Deca-BDE industrial formulations of PBDEs, are classed as persistent organic pollutants (POPs) underneath the UNEP Stockholm Conference. As well as, some PAH are labeled as human carcinogens, whereas some OPEs are into account for restriction by the European Chemical substances Company.

Co-author Professor Stuart Harrad, from the College of Birmingham, mentioned, “Our findings have implications for future space stations and habitats, the place it could be potential to exclude many contaminant sources by cautious materials decisions within the early levels of design and development.

“Whereas concentrations of natural contaminants found in dust from the ISS usually exceeded median values present in properties and different indoor environments throughout the US and western Europe, ranges of those compounds have been usually inside the vary discovered on earth.”

Researchers notice that PBDE concentrations within the dust pattern falling inside the vary of concentrations detected in US home dust could replicate use on the ISS of inorganic FRs like ammonium dihydrogen phosphate to make materials and webbing flame retardant. They imagine that the usage of commercially out there off-the-shelf objects introduced on board for the non-public use of astronauts, resembling cameras, MP3 gamers, tablet computers, medical units, and clothes, are potential sources of lots of the chemical compounds detected.

Air contained in the ISS is consistently recirculated with eight to 10 modifications per hour. Whereas CO₂ and gaseous hint contaminant removing happens, the diploma to which this removes chemical compounds like BFRs is unknown. Excessive ranges of ionizing radiation can speed up getting older of supplies, together with breakdown of plastic items into micro and nanoplastics that turn out to be airborne within the microgravity surroundings. This will likely trigger concentrations and relative abundance of PBDEs, HBCDD, NBFRs, OPEs, PAH, PFAS, and PCBs in ISS dust to vary notably from these in dust from terrestrial indoor microenvironments.

Scientists measured concentrations of a variety of goal chemical compounds in dust collected from the ISS. In a microgravity surroundings, particles float round based on air flow system circulation patterns, ultimately depositing on surfaces and air intakes.

Screens overlaying the ISS HEPA filters accumulate this particles, requiring weekly vacuuming to take care of environment friendly filtration. Materials in ISS vacuum luggage contains of beforehand airborne particles, clothes lint, hair and different particles usually recognized as spacecraft cabin dust. Some vacuum luggage have been returned to Earth for research of this distinctive dust, with a small pattern shipped to the College of Birmingham for evaluation within the examine.