Occupational endotoxin exposure and a novel luminol-enhanced chemiluminescence assay of nasal lavage neutrophil activation

Published: January 5th, 2011

Revised: July 21st, 2014

Methods to assess environmental endotoxin exposures might not accurately reflect personal exposure, and personal biomarkers of endotoxin would be valuable in determining inhaled endotoxin exposures. A method to detect endotoxin in human blood has been reported based on neutrophil-dependent chemiluminescence,1 and a modification to use the assay with nasal neutrophils from subjects who have been exposed to endotoxin demonstrated increased activation in response to exogenous LPS in vitro.2 The current study (which was approved by our research ethics board) evaluated the assay as a biomarker of in vivo nasal exposure to endotoxin and dusts in 33 animal care workers (ACWs; 70% women; mean age, 32.5 ± 9 years; 1 current smoker) compared with 20 nonexposed control subjects (85% women; mean age, 36.4 ± 9 years; 1 current smoker). ACW exposures included mice (100% of workers), rats (52%), guinea pigs (24%) and rabbits (20%). Atopy (as determined based on a positive skin prick test response to ≥1 of 13 common aeroallergen extracts) was not significantly different between groups (14 [54%] of 26 ACWs tested [4 with positive test results to a laboratory animal extract] and 25% of control subjects, P = .07). Histories of asthma (ie, cough, shortness of breath, and chest tightness) and allergy were slightly but not significantly more common in the exposed group than in the control subjects (21% vs 10% with asthma and 58% vs 45% with a self-reported history of allergy). Daily nasal symptoms were reported in 52% of ACWs and 30% of control subjects (P = .16). Seventy percent of ACWs had worked in this job for less than 3 years, but almost all (93%) reported cleaning at least 50 animal cages per day. Twenty-one percent of ACWs reported worsened nasal or chest symptoms at work.

View the full PDF article >