A wearable real-time particulate monitor demonstrates that soaking hay reduces dust exposure

• Published in: Equine veterinary journal 2024-10
• Main Authors: Ivester, Kathleen M, Ni, Ji-Qin, Couetil, Laurent L, Peters, Thomas M, Tatum, Marcus, Willems, Lynn, Park, Jae Hong
• Format: Article
• Language: English
• ISSN: 0425-1644; 2042-3306; 2042-3306
• DOI: 10.1111/evj.14425

Affordable particulate matter (PM) monitors suitable for use on horses will facilitate the evaluation of PM mitigation methods and improve the management of equine asthma. Calibrate a real-time wearable PM monitor (Black Beauty [BB]) and compare the PM exposures of horses fed dry or soaked hay. Laboratory calibration; complete cross-over feed trial. Side-by-side sampling with BB monitors and tapered element oscillating microbalances (TEOMs) was performed under varying concentrations of PM from alfalfa hay. Linear regression was used to derive a calibration formula for each unit based on TEOM PM measurements. Precision was evaluated by calculating the coefficient of variation and pairwise correlation coefficients between three BB monitors. PM exposure was measured at the breathing zone of 10 horses for 8 h after they were fed dry or soaked hay. Repeated measures generalised linear models were constructed to determine the effect of hay treatment and measurement duration (initial 20-min vs. 8-h) upon exposure to PM with diameters smaller than or equal to 10 μm (PM ) and 2.5 μm (PM ). BB monitor PM and PM measurements were linearly correlated with TEOM data (coefficient of determination r  > 0.85 and r  > 0.90 respectively), but underestimated PM mass concentrations by a factor of 4 and PM concentrations by a factor of 44. Measures from the three BB monitors had a coefficient of variation  0.98. Feeding soaked hay significantly reduced average PM exposures (20-min: dry: 160 μg/m , soaked: 53 μg/m , p