VOC sampling locations table for Ground Zero area, Jan 2002

NYC 9/11 Public Portal Document

Table 22 Estimation of WTC PMj j Concentrations Required to Produce Human Doses Equivalent to Mouse Doses Used in WTC2001 Study Dose deposited in mouse tracheobronchial and pulmonary regions (pg) 10 31.6 100 Mouse alveolar pulmonary surface area (m’)" 0.103 0.103 0.103 Mouse dose per tracheobronchial (TB) or pulmonary surface area (mg/m’) * 0.097 0.307 0.973 Human TB surface area (m^) ‘ 0.415 0.415 0.415 Total human TB dose equivalent to mouse TB dose (mg/m’ x m^) “ 0.040 0.128 0.404 Deposition fraction in human TB region ’ 0.066 0.066 0.066 Total inhaled dose in mg (total human TB dose / TB deposition fraction) 0.612 1.932 6.115 Quantity of air breathed in 8 hr workshift at ventilation of 30 L/min (m’) 14.4 14.4 14.4 WTC PM2 5 concentrations required to produce human doses equivalent to mouse doses used in WTC2001 Study (pg/m’) 42 134 425

“ From Jones and Longworth (1992) calculated allometric equation: Mammalian alveolar pulmonary surface area in m^ = 3.36 x (Wt, kg)"”’, where weight = 0.024 kg (average mouse weight in all studies). Tracheobronchial surface area is minimal in comparison to alveolar surface area and can be ignored in calculation. *’ Assumes dose is spread out evenly over tracheobronchial and pulmonary alveolar regions. ' Based on 30 year old, 5' 10” male with functional residual capacity (FRC) of 3300 ml (Overton et al., 2001). '* Calculations assume no clearance of particles after deposition in human respiratory tract. ' Calculations made with Multiple Path Particle Deposition model version 1.11 (Freijer et al., 1999) which assume human Yeh-Schum 5-lobe model, FRC = 3300 ml (appropriate for 30 year old, 5T 0" male), upper respiratory tract volume = 50 ml, density of particles = 1 gm / cc, diameter = 1 pm MMAD, inhalability adjustment on, og = 2.5, breathing frequency =15 min"', tidal volume = 2000 ml, minute volume = 30 L/min, inspiratory:expiratory ratio = 1, and oronasal mouth breathing. f Estimate of minute ventilation during moderate to heavy sustained work (Astrand and Rodahl, 1986).

old 5' 10" male breathing oronasally with a minute approximate the 100 pg dose in the mouse. Therefore, ventilation of30 L/min (estimate during moderate to heavy inhalation of a very high concentration ofWTC PM25 (e.g. sustained work; Astrand and Rodahl, 1986). The total -425 pg/m’) over a short period of time (8 hr) could have human TB dose and the fraction deposited in the TB contributed to development of pulmonary inflammation, region are used to back-calculate the total inhaled dose of airway hyperresponsiveness, and manifestations ofsensory PM2,5. The total inhaled dose divided by the quantity of irritation such as cough. Individuals who are especially air breathed in a typical 8-hour work shift yields the sensitive to inhalation of dusts, such as asthmatics, may concentration of PMj 5 in the WTC work or neighborhood experience these effects at lower doses of inhaled WTC environment required to produce human doses equivalent PM2.5. However, most healthy people would not be to the mouse doses used in the WTC2001 study (Table expected to respond to moderately high WTC PM2 5 levels 22). These calculations show that under these conditions, (130 pg/m’ or less for 8 hours) with any adverse concentrations of 42, 134, and 425 pg/m’ WTC PM2.5 respiratory responses. The effects of chronic or repeated would produce human doses per TB surface area exposures to lower levels ofWTC PM2.5, or the persistence equivalent to the mouse doses of 10, 31.6, and 100 pg, of any respiratory effects are unknown and were not respectively. Obviously many factors may cause wide components of this study. The persistence of any effects variations in the calculation of dose, and extrapolation of of inhaled WTC PM2.5, if similar to RADS, would be responses from the mouse to the human involves another expected to depend on the dose initially deposited in the dimension of uncertainty which was not considered, but it respiratory tract. seems reasonable to say that a healthy worker breathing It is important to consider several limitations of these heavily in the dusty environment generated after the studies. First, most ofthe experiments used oropharyngeal collapse of the towers could have inhaled enough PM2,5 to aspiration to deliver PM samples to the respiratory tract

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