Biomaterial Database

Acceptable Limits for n-Hexane in Spacecraft Atmospheres. 2021

Hector D Garcia

INTRODUCTION:The Spacecraft Maximum Allowable Concentrations (SMACs) for C2-C9 alkanes set by NASA in 2008 under the guidance and approval of the National Research Council specifically excluded SMACs for n-hexane. Unlike other C2-C9 alkanes, n-hexane can cause polyneuropathy after metabolism in humans or rodents and so requires more stringent SMACs than the other members of this group do. This document reviews the relevant published studies of n-hexane toxicity to develop exposure duration-specific SMACs for n-hexane of 200 ppm for 1 hour, 30 ppm for 24 hours, and 2.4 ppm for 7 days, 30 days, 180 days, and 1000 days.Garcia HD.

UI	MeSH Term	Description	Entries
D008452	Maximum Allowable Concentration	The maximum exposure to a biologically active physical or chemical agent that is allowed during an 8-hour period (a workday) in a population of workers, or during a 24-hour period in the general population, which does not appear to cause appreciable harm, whether immediate or delayed for any period, in the target population. (From Lewis Dictionary of Toxicology, 1st ed)	Maximum Permissible Exposure Level,MPEL,Maximum Permissible Exposure Concentration,Allowable Concentration, Maximum,Allowable Concentrations, Maximum,Concentration, Maximum Allowable,Concentrations, Maximum Allowable,MPELs,Maximum Allowable Concentrations
D006586	Hexanes	Six-carbon saturated hydrocarbon group of the methane series. Include isomers and derivatives. Various polyneuropathies are caused by hexane poisoning.	Hexane,Isohexane,Isohexanes
D001272	Atmosphere	The gaseous envelope surrounding a planet or similar body. (From Random House Unabridged Dictionary, 2d ed)	Atmospheres
D018531	Spacecraft	Devices, manned and unmanned, which are designed to be placed into an orbit about the Earth or into a trajectory to another celestial body. (NASA Thesaurus, 1988)	Biosatellites,Launch Vehicle,Satellites, Artificial,Satellites, Man-Made,Space Capsule,Space Craft,Space Probe,Space Ship,Space Shuttle,Space Vehicles,Spaceship,Artificial Satellite,Artificial Satellites,Biosatellite,Capsule, Space,Capsules, Space,Launch Vehicles,Man-Made Satellite,Man-Made Satellites,Probe, Space,Probes, Space,Satellite, Artificial,Satellite, Man-Made,Satellites, Man Made,Shuttle, Space,Shuttles, Space,Space Capsules,Space Probes,Space Ships,Space Shuttles,Space Vehicle,Spacecrafts,Spaceships,Vehicle, Launch,Vehicles, Launch