The Toxicologist - Society of Toxicology

a limited subset of PAHs (16 US-EPA PAHs). Therefore, additional potential toxicity
assessment via in vitro assays as well as mechanistic studies e.g., assessing PAH
availability to the cells and understanding the activation and/or suppression of signal
transduction, appears warranted. The aim of this study was to assess PAH toxicity
via chemical PAH analysis, a specific in vitro PAH transactivation assay and
metabolism studies. Two different PM samples were analyzed (TD-GC-MS/MS)
for the presence of 16 PAHs. PAH-induced toxic potency was determined with the
PAH CALUX transactivation assay. The PAH CALUX system suggested the presence
of a toxic potency several fold above that indicated by chemical analysis. In addition,
human type II alveolar epithelial cells (A-549) were exposed to different PM
concentrations and Benzo(a)pyrene (B[a]P) as a positive control. PM as well as
B[a]P exposure resulted in a higher CYP1A1 mRNA expression than in controls.
CYP1A1 enzyme activity was confirmed via a luminogenic assay. CYP1A1 enzyme
activity was inhibited at high PM and B[a]P concentrations and assumed to result
from increased expression of AhRR, a repressor of the AhR signaling cascade.
Consequently understanding the status of both the AhR and AhRR appear important
in order to interpret the potential toxicity of PMs and B[a]P in human alveolar
cell systems.
1214 SULFUR EMISSIONS FROM CHINESE DRYWALL IN
CHAMBERS AND HOMES.
J. Matheson 1 , M. Babich 1 , T. Thomas 1 , K. Hatlelid 1 , J. Recht 1 , R. Maddalena 2 ,
M. Apte 2 , J. McCarthy 3 , B. Baker 3 , J. Allen 3 , D. MacIntosh 3 and L. Saltzman 1 .
1 U.S. Consumer Product Safety Commission, Bethesda, MD, 2 LBNL, Berkeley, CA
and 3 EH&E, Needham, MA.
The CPSC has received 3600 consumer complaints reporting health effects and
metal corrosion in homes built/renovated in 2001-2008. Reported health effects
include: migraines, nosebleeds, irritated eyes, dyspnea, cough, and sinus problems.
Affected homeowners often note the homes have an offensive odor. Certain drywall
imported from China (CDW) was implicated as the probable cause of reported corrosion;
but other home materials have not been ruled out as contributory factors.
Chamber testing of domestic and imported drywall emissions and in-home air sampling
are part of a multi-track test program to evaluate the relationship between
drywall emissions, material degradation, and reported symptoms. Chamber testing
on 30 drywall samples was performed at LBNL. Emissions from preconditioned
samples were measured in 10.5 L chambers at a ventilation rate of 0.5 L/min at
25°C and 50% relative humidity. Four methods were used for emission sampling
and analysis depending on the target chemical class. A new method, solid phase
micro extraction, was developed to measure reactive volatile sulfur gases. The majority
of emissions consisted of H 2 S and SO 2 ; total sulfur emission factors ranged
from 0.3 to 209 μg/m 2 /h. Higher sulfur gas emissions were observed from CDW
made in 2005-2006. EH&E’s investigation in 51 homes included source characterization
using FTIR and XRF; measurements of indoor environment including
gases, ventilation rate, temperature and relative humidity; and copper and silver
corrosion rates. Compared to control homes, complaint homes had significantly
higher H 2 S levels (0.82 μg/m 3 vs 〈LOD) and rates of copper sulfide (476 vs 〈LOD
A/30d) and silver sulfide corrosion (1472 vs 389 A/30d). A consistent finding of elevated
sulfur emissions associated with CDW was observed in the chamber and inhome
testing. The home sulfur gas levels were below known irritant levels; however,
it is possible that additive or synergistic effects of these and other compounds could
potentially cause irritant effects to consumers.
1215 EXPOSURE MODEL FOR INDIVIDUALS (EMI) IN
HUMAN HEALTH STUDIES: PREDICTING
RESIDENTIAL INDOOR EXPOSURES TO FINE
AIRBORNE PARTICLES.
M. Breen 1 , M. Breen 1, 2 , B. Schultz 1 , T. Long 1 , R. Williams 1 , A. Vette 1 and R.
Devlin 1 . 1 U.S. EPA, Research Triangle Park, NC and 2 North Carolina State
University, Raleigh, NC.
In many epidemiological studies, particulate matter (PM) is associated with increased
risk for adverse cardiopulmonary events. Due to cost and participant burden
of indoor and personal measurements, health studies often estimate exposures
using ambient measurements. However, ambient levels do not necessarily reflect
personal exposures since indoor levels can differ from ambient levels, and people
spend considerable time indoors. To reduce this exposure error, which adds uncertainty
to risk estimates, we are developing an exposure model for individuals (EMI)
in cohort health studies. A critical aspect of EMI is estimation of the ambient contribution
to concentrations within individual homes, where people spend most of
their time. A mass-balance indoor air quality (IAQ) model was linked to an air exchange
rate (AER) model to predict ambient-generated indoor PM 2.5 mass from
260 SOT 2011 ANNUAL MEETING
ambient concentrations, meteorology, and questionnaire data on housing characteristics
and operation. First, AER model predictions were compared to 642 daily AER
measurements across 31 detached homes in central North Carolina. For individual
model predicted and measured AER, median absolute difference was 40% (0.17 hr -
1 ). Second, IAQ model was evaluated with concurrent daily measurements of ambient
and residential indoor-outdoor PM 2.5 mass. Using cross validation, model predictions
were compared to measurements of ambient-generated indoor PM 2.5 ,
which were derived from sulfate (outdoor tracer of PM 2.5 ). For individual model
predictions and measurements, median absolute difference was 24% (2.2 μg/m 3 ).
This study demonstrates the ability of EMI to predict residential indoor PM 2.5 of
ambient origin in support of developing exposure metrics for health studies.
1216 EXPOSURE TO PHTHALATES AMONG
PREMENSTRUAL GIRLS FROM RURAL AND URBAN,
GHARBIAH, EGYPT.
J. Colacino 1, 2 , A. Soliman 2, 3 , M. Nahar 1 , A. Hablas 4 , I. Seifeldin 4 , A. Van
Zomeren-Dohm 1 , L. S. Rozek 1 and D. C. Dolinoy 1 . 1 Environmental Health
Sciences, University of Michigan School of Public Health, Ann Arbor, MI, 2 Center for
Global Health, University of Michigan, Ann Arbor, MI, 3 Epidemiology, University of
Michigan, Ann Arbor, MI and 4 Tanta Cancer Center, Gharbiah, Egypt.
Phthalates have been identified as endocrine active compounds associated with developmental
and reproductive toxicity. Phthalate exposure in premenstrual
Egyptian females, a potentially vulnerable population, remains unknown. The objective
of this study was to quantify phthalate exposure in premenstrual females
from rural and urban areas of the Gharbiah province of Egypt as well as describe
potential routes of exposure. We collected one spot urine sample from 60 premenstrual
females, 30 each from urban and rural areas, as well as anthropometrics and
questionnaire data regarding cooking, cosmetic use, and food storage behaviors.
Urinary concentrations of 11 phthalate metabolites were quantified by isotope dilution
tandem mass spectrometry at the National Center for Environmental Health
of the Centers for Disease Control and Prevention. Urinary concentrations of diethyl
phthalate and di(2-ethylhexyl) phthalate metabolites measured in this study
were similar to those measured in age-matched US girls in the National Health and
Nutrition Examination Survey 2003-2006. Median mono-benzyl phthalate concentrations
were higher in US girls (31.1 ng/mL) compared to Egyptians (1.6
ng/mL). In contrast, median levels of mono-isobutyl phthalate were higher in
Egyptians (21.1 ng/mL) compared to US girls (7.5 ng/mL). We found no significant
difference in concentrations of phthalate metabolites based on the urban or
rural status of the Egyptian girls. In principle components analysis, storage of food
in plastic was found to be associated with phthalate body burden (p=0.036), suggesting
that dietary intake is likely an important route of phthalate exposure in
both urban and rural Egyptians. These findings suggest that phthalate exposure in
developing countries may be of equal concern as in the US.
1217 BLOOD ANALYSIS OF SWEDISH FIRE VICTIMS 1992-
2009 SUGGEST HYDROGEN CYANIDE AS AN
IMPORTANT CAUSE OF DEATH.
K. Stamyr 1 , G. Thelander 2 , L. Ernstgård 1 and G. Johanson 1 . 1 Work Environment
Toxicology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm,
Sweden and 2 Department of Forensic Genetics and Forensic Toxicology, National
Board of Forensic Medicine, Linköping, Sweden.
BACKGROUND For people caught in fires, or fire fighters entering fires, a major
threat is posed by toxic fumes. 60-80% of all deaths related to fire have been attributed
to such fumes. Carbon monoxide (CO) is a major component and is commonly
thought to be the major cause of most fire-related fatalities. However, hydrogen
cyanide (HCN) is also formed, especially during combustion of
nitrogen-containing materials such as polyurethane foam, a material increasingly
encountered in indoor environments. The exact contribution of HCN to fire-related
fatalities is unknown (Stamyr et al. Toxicol. Lett. 2008). AIM The study was
undertaken to investigate the impact of HCN in relation to CO as a cause of intoxication
and death in fire victims. METHOD Swedish data on all fire victims in the
period 1992-2009 were collected from two nationwide forensic databases (ToxBase
and RättsBase). Among the 1300 victims, 500 had been analyzed for both carboxyhemoglobin
(COHb) and HCN in blood. Nearly half of the victims had lethal
COHb levels (>50% COHb). Further, 7% had HCN levels above 2 μg/g (an indication
of lethal or life-threatening intoxication), 30% had levels above 1 μg/g and
over 50% had levels above 0.5 μg/g (an indication of significant HCN exposure).
HCN continues to be eliminated from blood also after death (McAllister et al. J.
Anal. Toxicol. 2008) and the exact time lapse from death to sampling and analysis
is unknown for these blood samples. Thus, measured HCN is probably a serious
underestimate of true blood levels at the time of death. CONCLUSION Overall,
these Swedish forensic data suggest that HCN may be an equally or even more im-