A positive cannabinoids workplace drug test following the ingestion of commercially available hemp seed oil

J Anal Toxicol. Jul-Aug 1997;21(4):283-5. doi: 10.1093/jat/21.4.283.

Abstract

A commercially available health food product of cold-pressed hemp seed oil ingested by one volunteer twice a day for 4 1/2 days (135 mL total). Urine specimens collected from the volunteer were subjected to standard workplace urine drug testing procedures, and the following concentrations of 11-nor-delta9- tetrahydrocannabinol carboxylic acid (9-THCA) were detected: 41 ng/mL 9-THCA at 45 h, 49 ng/mL at 69 h, and 55 ng/mL at 93 h. Ingestion was discontinued after 93 h, and the following concentrations were detected: 68 ng/mL at 108 h, 57 ng/mL at 117 h, 31 ng/mL at 126 h, and 20 ng/mL at 142 h. The first specimen that tested negative (50 ng/mL initial immunoassay test, 15 ng/mL confirmatory gas chromatographic-mass spectrometric test) was at 146 h, which was 53 h after the last hemp seed oil ingestion. Four subsequent specimens taken to 177 h were also negative. This study indicates that a workplace urine drug test positive for cannabinoids may arise from the consumption of commercially available cold-pressed hemp seed oil.

MeSH terms

  • Artifacts
  • Cannabinoids / urine*
  • Cannabis*
  • Dietary Fats, Unsaturated / urine*
  • Dronabinol / analogs & derivatives*
  • Dronabinol / urine
  • Humans
  • Male
  • Middle Aged
  • Occupational Health*
  • Plant Oils*
  • Reference Values
  • Seeds

Substances

  • Cannabinoids
  • Dietary Fats, Unsaturated
  • Plant Oils
  • 11-nor-delta(9)-tetrahydrocannabinol-9-carboxylic acid
  • Dronabinol