48 U.S.C. § 734

The statutory laws of the United States not locally inapplicable, except as hereinbefore or hereinafter otherwise provided, shall have the same force and effect in Puerto Rico as in the United States, except the internal revenue laws other than those contained in the Philippine Trade Act of 1946 [ 22 U.S.C. 1251 et seq.] or the Philippine Trade Agreement Revision Act of 1955 [ 22 U.S.C. 1371 et seq.]: Provided, however , That after May 1, 1946 , all taxes collected under the internal revenue laws of the United States on articles produced in Puerto Rico and transported to the United States, or consumed in the island shall be covered into the treasury of Puerto Rico.