At least one pharmaceutical or byproduct was detected in testing within the watersheds of 28 major metropolitan areas, according to an Associated Press survey of 62 major water providers and data obtained from independent researchers.

Test protocols varied widely. Some researchers tested for more drugs than others. Thirty-five areas said they tested. Four said tests were negative and three said they were awaiting results. Twenty-seven locations said they had not tested watershed supplies.

Here's the list of the 28 areas with pharmaceuticals detected, with the number found and some examples.

Arlington, Texas: 5 (unspecified drugs)

Atlanta: 10 (including caffeine, sulfamethoxazole, diltiazem, acetaminophen, trimethoprim, cotinine and paraxanthine)

Cincinnati: 4 (gemfibrozil, ibuprofen, sulfamethaxazole and ethinyl estradiol)

Columbus, Ohio: 15 (including azithromycin, erythromycin, roxithromycin, tylosin, ciprofloxacin, ofloxacin and caffeine)

Concord, Calif.: (unspecified drugs)

Denver: (unspecified antibiotics)

Detroit: (unspecified total; including carbamazepine, caffeine, cotinine)

Fairfax, Va.: 8 (erythromycin, lincomycin, trimethoprim, tylosin, ciprofloxacin, ofloxacin and sulfamethoxazole)

Indianapolis: 2 (caffeine and cotinine)

Las Vegas: 9 (including sulfamethoxazole, atenolol, trimethoprim, meprobamate, phenytoin, carbamazepine and gemfibrozil)

Long Beach, Calif.: 9 (unspecified drugs)

Los Angeles: 9 (unspecified drugs)

Louisville, Ky.: 2 (ibuprofen and naproxen)

Milwaukee: 1 (cotinine)

Minneapolis: 3 (acetaminophen, caffeine and cotinine)

New York City: 16 (including atenolol, trimethoprim, carbamazepine, ibuprofen, estrogen, acetaminophen and diazepam)

Northern New Jersey: 13 (including acetaminophen, carbamazepine, codeine, dehydronifedipine, erythromycin, lincomycin and sulfadimethoxine)

Oklahoma City: 12 (including acetaminophen, fluoxetine, gemfibrozil, ibuprofen, iopromide, sulfamethoxazole and iopromide)

Omaha, Neb.: 2 (caffeine and sulfamethoxazole)

Philadelphia: 63 (including amoxicillin, aspirin, atorvastatin, bacitracin, diclofenac, phenytoin and fluoxetine)

Prince George's-Montgomery counties, Md.: 3 (caffeine, carbamazepine and cotinine)

Riverside County, Calif.: 9 (unspecified drugs)

San Diego: 12 (clofibrate, clofibric acid, ibuprofen and nine unspecified)

San Francisco: 1 (estrone)

Santa Clara, Calif.: (unspecified drugs)

Southern California: 9 (including atenolol, phenytoin, fluoxetine, gemfibrozil, meprobamate, naproxen and trimethoprim)

Virginia Beach, Va.: 4 (fluoxetine, estradiol, acetaminophen and ibuprofen)

Washington, D.C.: 5 (monensin, ibuprofen, caffeine, carbamazepine and sulfamethoxazole)