The Poison Pen: Bedside Diagnosis of Urinary Diquat
- Author(s): Vohra, Rais;
- Salazar, Anthony;
- Cantrell, F. L.;
- Fernando, Ravindra;
- Clark, Richard F.
- et al.
Published Web Locationhttps://doi.org/10.1007/s13181-010-0033-6
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.