Acute cardiovascular autonomic responses to inhaled particulates.

PURPOSE: Harmful effects of inhaled particulates have been established in epidemiologic studies of ambient air pollution. In particular, heart rate variability responses to high levels of environmental tobacco smoke (ETS), similar to responses observed during direct smoking, have been reported. We sought to determine whether such responses could be observed at lower particulate concentrations. METHODS: We monitored cardiovascular responses of non-smoking 21 women and 19 men to work-place-relevant levels of: ETS, cooking oil fumes (Coil), wood smoke (WS), and water vapor as sham control. Responses, tested on three consecutive days (random order of aerosol presentation), were averaged for each subject. RESULTS: Low frequency spectral powers of heart rate and blood pressure rose during recovery from exposure to particulate, but not to sham exposures. At breathing frequencies, spectral power of men's systolic pressure doubled, and baroreflex effectiveness increased, following ETS exposure. An index of sympathetic control of heart rate was more pronounced in men than women, in response to ETS and Coil, compared to WS and sham. CONCLUSIONS: When measured under controlled conditions, autonomic activities in non-smoking men and women exposed to low level, short term, particulate concentrations were similar to those observed during longer term, higher level exposures to ETS and to direct smoking. These increased indexes of sympathetic control of heart rate and peripheral vasomotion followed introduction of particulates by about 15 min. Finally, coupling of heart rate and systolic pressure indicated an increase in baroreflex activity in the response to breathing ETS that was less effective in men than women.

Quantitation of cotinine in nonsmoker saliva using chip-based nanoelectrospray tandem mass spectrometry.

A new analytical procedure was developed for the quantitation of nonsmoker salivary cotinine. Small volumes of saliva were diluted with water, fortified with cotinine-d3 (internal standard), then passed through small extraction columns. The analyte and internal standard were eluted with 0.1% (v/v) acetic acid/acetonitrile. Aliquots of each extract were analyzed directly, without chromatographic separation, using chip-based (NanoMate) nanospray tandem mass spectrometry. The calculated detection limit was 0.49 ng cotinine/mL saliva. This method was used to quantify salivary cotinine collected from nonsmoking human subjects living in one of three environmental tobacco smoke (ETS) exposure categories or "cells": 1. smoking home/smoking workplace; 2. smoking home/nonsmoking workplace; and 3. nonsmoking home/smoking workplace. Samples were collected during five sequential days, including Saturday, as part of a larger study to evaluate potential variability in exposure to ETS. Salivary cotinine measurements were made for the purpose of excluding misclassified smokers and for comparison with known levels of exposure to airborne nicotine in each exposure category. The concentrations observed were consistent with those reported from other large studies reported elsewhere. A non-parametric statistical test was applied to the data within each cell. No statistically significant differences were found between the mean cotinine concentrations collected on a weekday as compared to those collected on a weekend day. When the non-parametric test was applied to the three cells, a statistically significant difference was observed between cell 1 compared to cells 2 and 3. The salivary cotinine concentrations were thus statistically invariant over a five-day exposure period, and they were greatest under the conditions of smoking home and smoking workplace.

Development and application of protocols for the determination of response of real-time particle monitors to common indoor aerosols.

Protocols have been developed and applied for the generation of aerosols that are likely to be comparable to those encountered in field settings for the calibration of easily transportable/portable real-time particle monitors. Aerosols generated were simulated environmental tobacco smoke, cedar wood smoke, cooking oil fumes, and propane stove particles. The time-integrated responses of three nephelometers and a monitor for particle-bound polynuclear aromatic hydrocarbons (PAH) were compared with gravimetric respirable suspended particulate matter (RSP) in a controlled-atmosphere chamber. In general, the monitor responses increased linearly with increasing mass concentration. However, the two monitors that reported mass per volume concentrations tended to overreport the actual RSP concentrations by factors up to 4.4. The real-time PAH monitor did not respond to cooking oil fumes, indicative of little PAH being present in the aerosol. One of the monitors that has been used in a variety of studies reported in the literature (DustTrak) was collocated with gravimetric RSP samplers in several hospitality venues in the Louisville, KY, area. Field studies indicated that the units overreported actual RSP concentrations by factors of 2.6-3.1, depending on whether the sampling was conducted in the nonsmoking or smoking sections of the facilities.