WASHINGTON — As much of his government battles the coronavirus outbreak, President Trump is pushing ahead with major reversals of environmental regulations, including a restriction on scientific research that some doctors worry would complicate future pandemic controls.

Federal employees across multiple agencies said the administration was racing to complete a half-dozen significant rollbacks over the coming month. They include a measure to weaken automobile fuel efficiency standards, which one person familiar with the plans said would be issued as early as next week.

Other efforts include loosening controls on toxic ash from coal plants, relaxing restrictions on mercury emissions and weakening the consideration of climate change in environmental reviews for most infrastructure projects.

The aggressive timeline is aimed at shielding the policies from easy reversal if Democrats win the White House or control of the Senate in the 2020 election. While it is hardly unusual to see a push to finalize policies toward the end of an administration, several agency officials said they were surprised that political leaders had shown no sign of letting up amid the pandemic.