, Volume 6, Issue 1, pp 35-36,
Open Access This content is freely available online to anyone, anywhere at any time.
Date: 13 Mar 2010

The Poison Pen: Bedside Diagnosis of Urinary Diquat

Abstract

Diquat is a bipyridyl herbicide with nephrotoxic effects. This in vitro study demonstrates a colorimetric test for detection of diquat in human urine. Urine specimens using ten concentrations of diquat herbicide solution and controls for urine and glyphosate were prepared. A two-step assay (addition of bicarbonate followed by sodium dithionite) was performed, with a resulting color change of the original solution for each specimen. Color change intensity was noted immediately and after 30 min, by gross visual inspection. A green color with concentration-dependent intensity was detected in all specimens, in which concentrations of diquat solution ranged from 0.73 to 730 mg/L. This colorimetric effect disappeared after 30 min. The sodium bicarbonate/dithionite test may be useful as a qualitative bedside technique for the detection of urinary diquat in the appropriate clinical setting.

Presentation Information

The preliminary findings of this study were presented as a poster at the Annual Congress of European Association of Poison Control Centers, Athens, Greece 2007.
All photos are owned by Rais Vohra, MD (first author and corresponding author).