Detection of organophosphate pesticides using a prototype liquid crystal monitor
| Autor: | Peter C. Raynor, Andrew D. Ryan, Bharat R. Acharya, Carla J. Volkmann, Darrin D. Most, John L. Adgate, Siyi Lai, Michael D. Bonds, J. Girard Griggs, Andrea Barteková |
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| Rok vydání: | 2009 |
| Předmět: |
Accuracy and precision
Air Pollutants Diazinon Chemistry Organophosphate Public Health Environmental and Occupational Health Parts-per notation Temperature Humidity General Medicine Management Monitoring Policy and Law Pesticide equipment and supplies Organophosphates Aerosol Liquid Crystals chemistry.chemical_compound Environmental chemistry Relative humidity Pesticides Environmental Monitoring |
| Zdroj: | Journal of environmental monitoring : JEM. 11(1) |
| ISSN: | 1464-0333 |
| Popis: | 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 approximately 8 to 108 ppb (parts per billion) over durations of 2 to 80 hours. Temperature ( approximately 25, 30, and 35 degrees 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 approximately 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. |
| Databáze: | OpenAIRE |
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