Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance upgrade on Thursday 4th of May 2017 from 8.00am to 9.00am (BST).

During this time our websites will be offline temporarily. If you have any questions please use the feedback button on this page. We apologise for any inconvenience this might cause and thank you for your patience.

Issue 1, 2009
Previous Article Next Article

Detection of organophosphate pesticides using a prototype liquid crystal monitor

Author affiliations


The precision and accuracy of a prototype wearable liquid crystal monitor (LCM) for the measurement of airborne organophosphate pesticide concentrations was explored in a series of laboratory experiments. LCM response to vapor-phase and aerosol diazinon was compared to concentrations obtained using a standard reference method (NIOSH 5600) at concentrations ranging from ∼8 to 108 ppb (parts per billion) over durations of 2 to 80 hours. Temperature (∼25, 30, and 35 °C) and relative humidity (15, 50, and 85%) were varied to estimate the effect of these factors on LCM performance. The LCM response to vapor phase pesticide exposure was linear for concentrations in the range of 8–20 ppb. At exposure concentrations above ∼20 ppb, however, there was a decline in monitor response and measurement precision. Elevated temperatures improved diazinon vapor-only measurement precision, while increased relative humidity reduced LCM response at the extremes of tested temperatures. Compared to vapor-only exposures, the LCM was less sensitive to diazinon aerosol concentrations, but displayed reasonable precision over a relatively large range of exposures (29 to 1190 ppb-hr). Further efforts to characterize temperature and humidity effects and improve low-end sensitivity would likely provide a portable personal exposure monitor or environmental sensor for this widely used class of pesticides.

Graphical abstract: Detection of organophosphate pesticides using a prototype liquid crystal monitor

Back to tab navigation
Please wait while Download options loads

Publication details

The article was received on 24 Apr 2008, accepted on 15 Oct 2008 and first published on 13 Nov 2008

Article type: Paper
DOI: 10.1039/B806954A
Citation: J. Environ. Monit., 2009,11, 49-55
  •   Request permissions

    Detection of organophosphate pesticides using a prototype liquid crystal monitor

    J. L. Adgate, A. Barteková, P. C. Raynor, J. G. Griggs, A. D. Ryan, B. R. Acharya, C. J. Volkmann, D. D. Most, S. Lai and M. D. Bonds, J. Environ. Monit., 2009, 11, 49
    DOI: 10.1039/B806954A

Search articles by author