Ambrosio Garcia-Camacho (“Garcia”) appeals his guilty-plea conviction and sentence for possession with intent to distribute more than 500 grams of cocaine, in violation of 21 U.S.C. § 841(a)(1) and (b)(1)(B). Garcia claims the district court clearly erred in refusing to grant his request for a two level reduction for being a minor participant pursuant to U.S.S.G. § 3B1.2(b). Garcia contends that he "is eligible for a minor participant reduction because he was merely a one-time drug courier even though he was the only defendant indicted in this case and was the only person involved in the transportation of this cocaine. A district court’s interpretation of the Guidelines is reviewed de novo; its findings of fact, for clear error. E.g., United States v. Claiborne, 132 F.3d 253, 254 (5th Cir.), cert. denied, 523 U.S. 1144, 118 S.Ct. 1855, 140 L.Ed.2d 1103 (1998).

Although a drug courier is not precluded from qualifying as a minor participant, see United States v. Sotelo, 97 F.3d 782, 799 (5th Cir. 1996), a defendant “may be a courier without being substantially less culpable that the average participant”. United States v. Brown, 54 F.3d 234, 241 (5th Cir. 1995). The large quantity of cocaine being transported by Garcia supports the district court’s determination that Garcia was not a minor participant. See United States v. Rojas, 868 F.2d 1409, 1409-10 (5th Cir. 1989). And, obviously, the district court was not required to accept Garcia’s account of his role in the drug trafficking scheme. See United States v. Buenrostro, 868 F.2d 135, 138 (5th Cir. 1989), cert. de *398 nied, 495 U.S. 923, 110 S.Ct. 1957, 109 L.Ed.2d 319 (1990). Accordingly, the ruling was not clearly erroneous. See id.

For the first time on appeal, Garcia contends that 21 U.S.C. §§ 841(a) and (b) are facially unconstitutional in the light of Apprendi v. New Jersey, 530 U.S. 466, 490, 120 S.Ct. 2348, 147 L.Ed.2d 435 (2000). As Garcia concedes, his contention is foreclosed by United States v. Slaughter, 238 F.3d 580, 582 (5th Cir. 2000), cert. denied, 532 U.S. 1045, 121 S.Ct. 2015, 149 L.Ed.2d 1015 (2001). He raises the issue only to preserve it for possible further review.

AFFIRMED