VOC sampling locations table for Ground Zero area, Jan 2002

NYC 9/11 Public Portal Document

(frequency, f, breaths / min) and other parameters under the curve (PenH AUC; PenH - sec) for these including enhanced pause (PenH). Although PenH is at recording intervals was calculated using the trapezoid best an indirect measure of flow resistance, it does method. correlate well with lung resistance and reflects changes occurring during bronchoconstriction (Hamelmann et al., K. Diffusing Capacity of the Lung for Carbon 1997), although other responses such as mucus production Monoxide. may increase PenH. The convenience of rapidly The ability of the lungs to allow diffusion of gases measuring respiratory parameters in twelve mice at once (Oj, CO2) across the alveolar-capillary barrier is dependent was a major consideration in utilizing this technique rather on physical properties of the gases and the alveolar- than the double plethysmograph or tracheotomized capillary membrane, and may be limited by perfusion or ventilated methods which allow direct measures ofairways diffusion (Levitzky, 1995). Diffusion limitation may be resistance and compliance, but are time and labor caused by thickening of the alveolar-capillary barrier (e.g. intensive. A protocol was written to record and average by interstitial or alveolar edema). Diffusion of carbon baseline measurements of mice in calibrated chambers for monoxide (CO) is limited only by its diffusivity in the 10 min, pause for oropharyngeal aspiration (or stop during barrier and by the surface area and thickness of the barrier. inhalation exposure), and then resume recording The diffusing capacity of the lung for CO (DLCO) is measurements for one hour. The time between therefore a useful test of the integrity of the alveolar- oropharyngeal aspiration and monitoring ofresponses was capillary membrane (Levitzky, 1995). approximately 6 minutes, while about 20 minutes was To determine DLCO rapidly and increase sensitivity needed after inhalation exposure to remove mice from from individual mice, 4 mice were placed together in a exposure tubes, weigh them, and transport them to the single 7.8 L bell jar associated with a Pharmacokinetic plethysmograph chambers. PenH was automatically Uptake System (consisting of an oxygen monitor, flow calculated by the software (and confirmed by examination meter, pump, pressure gauge and transducer, mass flow ofrandom data) using expiration time (T e), relaxation time controller, and computerized data collection and control (RT), and peak expiratory and inspiratory flows (PEF, system). Approximately 6.6 ml of research grade CO PIF) according to the following expression: PenH = [(Te- (99.99%) was injected into the system. The initial RT)/RT] X [PEF/PIF]. Examination of the data after concentration of CO in the chamber was approximately exposure showed that utilization of the first 10 or 15 700 ± 10 ppm. CO concentrations were taken every 15 minutes of the data was not more sensitive in detecting seconds (Bendix Model 8501-5CA CO Analyzer), and changes in respiratory parameters than the entire hour of continued for approximately 10 minutes. Temperature, post-exposure monitoring, and therefore responses over humidity, airflow, pressure, and oxygen were monitored the whole post-exposure hour were utilized and averaged. during the test. The DLCO is expressed as the slope of the The percent change in f and PenH after exposure to PM fitted line of [CO] vs. time (ppm/min). was expressed as [(Post-value - Pre-value) / Pre-value] x 100%. L. Bronchoalveolar Lavage (BAL). 2. Airway Responsiveness to Methacholine AerosoL Mice were anesthetized with urethane (1.5 g/kg i.p.) Airway responsiveness to increasing concentrations of and killed by exsanguination via severing the renal artery. aerosolized methacholine (Meh) was measured in mice in The trachea and lungs were exposed and a 20 g catheter calibrated chambers. After measurement ofbaseline PenH was sutured into the trachea. Mice were lavaged with two for 5 minutes, saline or Meh in increasing concentrations aliquots of Ca^’, Mg^*, and phenol red-free Hanks’ (4, 8, 16, 32, and 64 mg/ml) was nebulized through an balanced salt solution (HBSS; 35 ml/kg. Life inlet of the chamber for 1 min. The aerosol drier was Technologies, Bethesda, MD). Approximately 85% ofthe automatically turned on immediately after the total instilled volume was recovered in all treatment aerosolization period for 2 min. Measurements of PenH groups. The BAL fluid was maintained on ice and and other parameters were continued for an additional 1, centrifuged at 360 x g for 10 minutes at 4 °C. 2, 3,4, 8, and 12 minutes after saline or increasing doses Supernatants were transferred to a separate tube in order of Meh, for a total time of 4,5,6,7,11, and 15 minutes (0, to prepare aliquots for biochemical analyses. BAL cells 4, 8, 16, 32, 64 mg/ml Meh, respectively). One minute were resuspended in 1 ml of HBSS and counted (Coulter pause periods between aerosolizations allowed time to Zl, Hialeah, FL). Cytospin preparations of BAL cells change solutions for nebulization. After subtracting were made for each sample and stained with Wright’s baseline values from responses to saline or Meh, the area Giemsa using an automated slide Stainer (Hematek 2000,

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