Air quality may be the first concern in the mind of anyone who has seen the rocket's long trail of vapor across the evening sky, yet the reported emissions are below applicable state and federal standards.

"The exhaust from Falcon 9 rocket launches is fuel-rich and contains high concentrations of carbon monoxide (CO)," states the commission's report. "Subsequent entrainment of ambient air results in complete conversion of CO into carbon dioxide (CO2) and oxidation of the soot from the exhaust."

The liquid rocket fuel consists rocket-grade kerosene combined with liquid oxygen. When it burns it produces "a diminutive amount of soot" and a small amount of nitrogen oxide (NO) in the exhaust. As a result, the emissions conform to the standards of the federal Clean Air Act.

Weather balloons related to the launches are a significant source of marine debris, the report states.

"Up to 36 weather balloons would be released prior to each launch to measure upper atmosphere conditions and would then fall to the ocean below in state or federal waters," it states. "Due to the height it would fall from and large ocean area in may land in ... it would not be feasible to recover each weather balloon and associated instrument array."

The payload includes a fairing or shield that is released in space and falls to earth, slowed by a parachute, but that cannot be recovered. Also, in some cases the first stage of the rocket may fall into the ocean and not be recovered.

As a result, SpaceX is required to make a monetary donation of $10 for each pound of ocean debris to the University of California Davis' California Lost Fishing Gear Recovery Project.

The launches also expose wildlife to "elevated sound levels," although so far no adverse effects have been determined.

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