http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15050396
Sci Total Environ. 2004 Apr 5;321(1-3):201-17.
Historical trends in occurrence and atmospheric
inputs of halogenated volatile organic compounds in untreated
ground water used as a source of drinking water.
Shapiro SD, Busenberg E, Focazio MJ, Plummer
LN.
US Geological Survey, MS 432, 12201 Sunrise Valley Drive, Reston,
VA 20192, USA.
Analyses of samples of untreated ground water from 413 community-,
non-community- (such as restaurants), and domestic-supply wells
throughout the US were used to determine the frequency of detection
of halogenated volatile organic compounds (VOCs) in drinking-water
sources. The VOC data were compiled from archived chromatograms
of samples analyzed originally for chlorofluorocarbons (CFCs)
by purge-and-trap gas chromatography with an electron-capture
detector (GC-ECD). Concentrations of the VOCs could not be ascertained
because standards were not routinely analyzed for VOCs other than
trichloromonofluoromethane (CFC-11), dichlorodifluoromethane
(CFC-12) and 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113).
Nevertheless, the peak areas associated with the elution times
of other VOCs on the chromatograms can be classified qualitatively
to assess concentrations at a detection limit on the order of
parts per quadrillion. Three or more VOCs were detected in 100%
(percent) of the chromatograms, and 77.2% of the samples contained
10 or more VOCs. The maximum number of VOCs detected in any sample
was 24. Modeled ground-water residence times, determined from
concentrations of CFC-12, were used to assess historical trends
in the cumulative occurrence of all VOCs detected in this analysis,
as well as the occurrence of individual VOCs, such as CFC-11,
carbon tetrachloride (CCl(4)), chloroform and tetrachloroethene
(PCE). The detection frequency for all of the VOCs detected has
remained relatively constant from approximately 1940 to 2000;
however, the magnitude of the peak areas on the chromatograms
for the VOCs in the water samples has increased from 1940 to 2000.
For CFC-11, CCl(4), chloroform and PCE, small peaks decrease from
1940 to 2000, and large peaks increase from 1940 to 2000. The
increase in peak areas on the chromatograms from analyses of more
recently recharged water is consistent with reported increases
in atmospheric concentrations of the VOCs. Approximately 44% and
6.7% of the CCl(4) and PCE detections, respectively, in pre-1940
water, and 68% and 62% of the CCl(4) and PCE detections, respectively,
in water recharged in 2000 exceed solubility equilibrium with
average atmospheric concentrations. These exceedences can be attributed
to local atmospheric enrichment or direct contaminant input to
ground-water flow systems. The detection
of VOCs at concentrations indicative of atmospheric sources in
100% of the samples indicates that untreated drinking water from
ground-water sources in the US recharged within the past 60 years
has been affected by anthropogenic activity. Additional inputs
from a variety of sources such as spills, underground injections
and leaking landfills or storage tanks increasingly are providing
additional sources of contamination to ground water used as drinking-water
sources.
PMID: 15050396 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15180066
Environ Sci Technol. 2004 May 1;38(9):2685-92.
Standards development of global warming
gas species: methane, nitrous oxide, trichlorofluoromethane, and
dichlorodifluoromethane.
Rhoderick GC, Dorko WD.
National Institute of Standards and Technology, Analytical Chemistry
Division, 100 Bureau Drive, Building 227/Room B120, Gaithersburg,
Maryland 20899-8393, USA. george.rhoderick@nist.gov
Environmental scientists from federal agencies, such as the National
Oceanic and Atmospheric Administration (NOAA), and academia have
long suspected that increasing anthropogenic inputs of various
trace gases into the atmosphere can cause changes in the earth's
climate and protective ozone layer. Nitrous oxide and methane,
cited in the Kyoto Protocol, as well as trichlorofluoromethane
(CFC-11) and dichlorodifluoromethane (CFC-12),
cited in the Montreal Protocol, are all greenhouse gases and are
implicated in the destruction of the stratospheric ozone layer.
The lack of national standards prompted research to determine
the feasibility of preparing accurate and stable standards containing
these four compounds. Development of these standards would support
the measurement of these species by those in the atmospheric research
community not having their own source of standards. A suite of
eight primary gas standards containing methane, nitrous oxide,
CFC-11, and CFC-12 in a balance of air were prepared gravimetrically
to bracket the ambient atmospheric concentrations. The combined
uncertainties (uc) were calculated from error propagation analysis
that included the weighing data from the gravimetric preparation
and other sources of error such as the purity analysis of the
compounds and air matrix. The expanded uncertainties (U) for the
gravimetric standards were < 0.5% as calculated from the equation
U = kuc, where the coverage factor k is equal to 2 for a 95% confidence
interval. Analyses of the suite of standards by gas chromatography
with flame-ionization and electron capture detection resulted
in average absolute residuals of < 0.25% from regression models.
The NIST suite of eight gravimetric standards was used to determine
the concentrations in two standardsfrom NOAA. Those analyses resulted
in bias across the two laboratories of < or = 2.1%.
PMID: 15180066 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11516020&dopt=Abstract
Environ Monit Assess.
2001 Jul;70(1-2):47-56.
Background
monitoring and long-range transport of atmospheric CFC-11 and
CFC-12 at Kosan, Korea.
Kim
J, Oh SN, Cho HM, Park MK, Kim KR, Elkins JW.
Applied Meteorology
Research Laboratory, Meterological Research Institute, Seoul,
Korea. jykim@metri.re.kr
The background concentrations
of atmospheric CFC-11 and CFC-12
were monitored to assess their impact on stratospheric ozone depletion
and global warming from September 1995 to March 1999 at Kosan,
Korea, located at eastern margin of the Asian Continent. The concentrations
of atmospheric CFC-11 at Kosan have decreased slightly, at a rate
of -2.5 pptv yr(-1), over the period in response to the Montreal
Protocol. The CFC-12 mixing ratio at Kosan
continues to increase in the atmosphere at a rate of 5.7 pptv
yr(-1) despite international regulations, because of its extreme
atmosphere persistence. Recent trends of these two chlorofluorocarbons
at Kosan, Korea were concordant with those of the northern hemispheric
background monitored unit at Mauna Loa, Hawaii. The maximum seasonal
mean mixing ratios of CFC-11 and CFC-12 at Kosan, Korea, were
270 +/- 4 pptv in the spring and 538 +/- 9 pptv in the winter,
and the corresponding seasonal minima were 267 +/- 7 and 529 +/-
12 pptv. This occurred in the summer and was due to southeasterly
winds from the northwestern Pacific Ocean. By performing a three-day
isentropic backward trajectory analysis, it was shown that air
masses at Kosan, and with the exception of summer, mainly originated
from central and northern China. In particular, the mixing ratios
of these two contaminant species are closely related with their
air mass trajectories.
PMID: 11516020
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10914338&dopt=Abstract
J Occup Environ Med.
2000 Jul;42(7):693-703.
Use of
a job-exposure matrix to assess occupational exposures in relation
to birth defects.
Louik
C, Frumkin H, Ellenbecker MJ, Goldman RH, Werler MM, Mitchell
AA.
Slone Epidemiology
Unit, School of Public Health, Boston University School of Medicine,
Brookline, Mass., USA. clouik@slone.bu.edu
Accurate exposure assessment
remains a challenge in occupational epidemiology. We evaluated
one approach, use of a job-exposure matrix (JEM), by applying
the National Institute for Occupational Safety and Health (NIOSH)
JEM to a large case-control birth defects study that included
parental occupation information. We investigated the JEM exposure
predictions in several ways and found that for a substantial proportion
of the parents in the birth defects study, the JEM yielded either
no exposure data or nonsense predictions. Among exposure predictions
that were plausible, most were of low probability. The high probability
exposure predictions were statistically unstable, and neither
low nor high probability exposure predictions were reliable. There
was considerable discrepancy between the JEM predictions and expert
assessments for five exposures of interest. Application of the
NIOSH JEM to the birth defects study database (and probably other
databases as well) does not provide a useful means of assessing
occupational exposures.
PMID: 10914338
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8638181&dopt=Abstract
South Med J. 1996
May;89(5):516-8.
Secondary
arterial hypertension linked to Freon exposure.
Voge
VM.
Naval School of Health
Sciences Bethesda Detachment, Fort Sam Houston, Tex., USA.
Freons are generally
considered to be minimally toxic. There are no reports in the
literature of Freons causing secondary arterial hypertension.
We report two cases of acute, massive Freon exposure that preceded
secondary arterial hypertension. We hypothesize that the arterial
hypertension was precipitated by renal proximal tubular damage,
although several other mechanisms are possible.
PMID:
8638181 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7924293&dopt=Abstract
Contact Dermatitis.
1994 Jul;31(1):41-4.
Allergic
contact dermatitis from ethyl chloride and sensitization to dichlorodifluoromethane
(CFC 12).
Bircher
AJ, Hampl K, Hirsbrunner P, Buechner SA, Schneider M.
Department of Dermatology,
University Hospital, Basel, Switzerland.
Despite the widespread
use of ethyl chloride as a local anesthetic and chlorofluorocarbons
as propellants in medical and cosmetic aerosols, contact allergy
to these 2 gases is rare. In a 30-year-old woman, an unusual itchy
dermatitis appeared at all skin sites where a medical aerosol
containing ethyl chloride had been briefly applied. Subsequent
re-exposure to the spray and patch tests revealed contact sensitization
to ethyl chloride and dichlorodifluoromethane (CFC 12). Histologic
and immunohistochemical examinations of the test reaction were
consistent with a T-cell-mediated allergic reaction. The low incidence
of contact allergy to ethyl chloride and chlorofluorocarbons may
be due to the rapid evaporation of these volatile gases, thus
preventing intense and prolonged contact with the skin and consequently
contact sensitization. A modified patch test procedure using perforated
plastic chambers to allow gas evaporation is necessary to test
volatile agents.
PMID: 7924293
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8349485&dopt=Abstract
J Am Osteopath Assoc.
1993 Jun;93(6):714-8.
Unexpected
adverse effects of Freon 11 and Freon 12 as medication propellants.
Oenbrink
RJ.
Metered-dose inhalers
are frequently used in treating pulmonary diseases associated
with bronchoconstriction, chiefly asthma and chronic bronchitis.
These aerosolized medications are not without the potential for
adverse effects. The author describes two patients who likely
had adverse reactions to the Freon propellants used in the inhalers.
These reactions are reported in order to alert physicians to their
possible occurrence and to suggest a rational treatment approach.
PMID: 8349485
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8455004&dopt=Abstract
J Forensic Sci. 1993
Mar;38(2):477-83.
Fatality
due to recreational use
of chlorodifluoromethane and chloropentafluoroethane.
Fitzgerald
RL, Fishel CE, Bush LL.
Mass Spectrometry Laboratory,
VA Hospital, San Diego, CA.
Reports on fatalities
of chlorofluorocarbons usually involve chlorotrifluoroethane,
trichlorofluoromethane, dichlorodifluoromethane
or chlorodifluoromethane, where analysis was done using packed
column gas chromatography. In this case a death was caused by
an azeotropic mixture of chlorodifluoromethane and chloropentafluoroethane,
a combination that has not previously been reported in the forensic
literature. This report details the analysis using mass selective
detection employing capillary gas chromatography columns currently
used in many toxicology laboratories. Postmortem toxicology revealed
blood concentrations of chlorodifluoromethane and chloropentafluoroethane
of 71 mg/L and 0.30 mg/L, respectively. Brain, liver, and lung
concentrations of chlorodifluoromethane were (mg/kg) 2.8, 4.4,
and 1.6, respectively. Brain, liver, and lung concentrations of
chloropentafluoroethane were (mg/kg) 0.80, 0.80, and 0.11, respectively.
The victim's blood contained 5.5 mg/L caffeine. Lidocaine, used
in resuscitation attempts, was also present in the victim's blood.
No other alkali-extractable drugs or volatile alcohols were detected
in the victim's blood. The cause of death was acute respiratory
arrest due to chlorofluorocarbon inhalation.
PMID: 8455004
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1510059&dopt=Abstract
Am J Forensic Med Pathol.
1992 Jun;13(2):115-9.
Atypical
autoerotic deaths.
Gowitt
GT, Hanzlick RL.
Fulton County Medical
Examiner's Office, Atlanta, GA 30303.
So-called "typical"
autoerotic fatalities are the result of asphyxia due to mechanical
compression of the neck, chest, or abdomen, whereas "atypical"
autoeroticism involves sexual self-stimulation by other means.
We present five atypical autoerotic fatalities that involved the
use of dichlorodifluoromethane, nitrous
oxide, isobutyl nitrite, cocaine, or compounds containing 1-1-1-trichloroethane.
Mechanisms of death are discussed in each case and the pertinent
literature is reviewed.
PMID: 1510059
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3389660&dopt=Abstract
Ann N Y Acad Sci. 1988;534:261-82.
Long-term
carcinogenicity bioassays on three chlorofluorocarbons (trichlorofluoromethane,
FC11; dichlorodifluoromethane,
FC12; chlorodifluoromethane, FC22) administered by inhalation
to Sprague-Dawley rats and Swiss mice.
Maltoni
C, Lefemine G, Tovoli D, Perino G.
Institute of Oncology
F. Addarii, Bologna, Italy.
Three propellant chlorofluorocarbons,
namely trichlorofluoromethane (FC11), dichlorodifluoromethane
(FC12), and chlorodifluoromethane (FC22) were administered by
inhalation at a concentration of 5000, 1000 and 0 ppm, 4 hours
daily, 5 days weekly, for 104 and 78 weeks, to rats and mice,
respectively. The animals were kept under observation until spontaneous
death. Under the experimental conditions, all three compounds
failed to show any carcinogenic effects.
PMID: 3389660
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3339298&dopt=Abstract
J Fam Pract. 1988
Jan;26(1):18.
No
Abstract available
Freon
12 and verruca lesions.
McDow
RA.
Publication Types:
Letter
PMID: 3339298
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3427952&dopt=Abstract
Contact Dermatitis.
1987 Oct;17(4):243-5.
No
Abstract available
Contact
allergic dermatitis caused by freon 12 in deodorants.
Valdivieso
R, Pola J, Zapata C, Cuesta J, Puyana J, Martin C, Losada E.
Servicio de Alergia,
Hospital Ramon y Cajal, Madrid, Spain.
PMID: 3427952
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3569997&dopt=Abstract
Gig Sanit. 1987
Mar;(3):73-4.
No
Abstract available
[Hygienic
evaluation of freon-12 and its allowable level in the water of
bodies of water]
[Article in Russian]
Antonova
VI, Salmina ZA, Petrova NA.
PMID: 3569997
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3781256&dopt=Abstract
Gig Sanit. 1986
Sep;(9):19-22.
No
Abstract available
[Hygienic
evaluation of the meat of birds frozen in a refrigerant medium
(freon-12)]
[Article in Russian]
Bronnikova
IA, Petrova GA, Venger KP, Mazurenko NP.
PMID: 3781256
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4026874&dopt=Abstract
Biochem Pharmacol.
1985 Aug 15;34(16):2839-46.
Effects
of anesthetics and dichlorodifluoromethane on the activities of
glyceraldehyde-phosphate dehydrogenase and pectin methylesterase.
Laverty
DM, Fennema O.
Solutions of glucose-3-phosphate
dehydrogenase (GPD) and pectin methylesterase (PME) were exposed
to various anesthetics and dichlorodifluoromethane
(F-12) to determine the abilities of these chemicals to
inhibit enzyme activity. An aqueous solution of PME was exposed
to saturation levels of the test chemicals for 30 min at 21 degrees.
All test chemicals were inhibitory (measured
after release of the test chemical) with propane being
most inhibitory followed in order by F-12,
cyclopropane, Ethrane (F2HCOF2CCHClF) and halothane (CF3CHClBr).
GPD was exposed to various concentrations of F-12 and halothane
for various times at 0 degrees and 33 degrees. Halothane at 33
degrees and a saturation concentration reduced the initial reaction
velocity of GPD to zero after a 10-min exposure period.
F-12 was somewhat less inhibitory than halothane, but inhibition
in all instances was irreversible. Halothane was found
to affect the circular dichroism and optical rotary dispersion
spectra of GPD, with the magnitude of the changes generally increasing
with treatment time. The observed changes were believed to arise
from side-chain transitions of GPD.
PMID:
4026874 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=6449983&dopt=Abstract
C R Seances Soc Biol
Fil. 1980;174(1):52-7.
[Effect
of difluorodichloromethane (FC 12) on the cardiac cellular electric
activity of mammals]
[Article in French]
Lessard
Y, Callec JJ, Paulet G.
The cardiotoxicity
of high concentrations of inhaled difluorodichloromethane (FC
12) has now been acknowledged. In the present study, the effects
of FC 12 on the electrical activity of cells in the atrial and
ventricular myocardium of anesthetized rats were recorded with
"flexibly mounted" intracellular microelectrodes. The
major phenomena observed in both types of cells were: a distinct
decrease in the diastolic potential, a decrease inthe amplitude
of the action potential, modifications in the shape of the action
potential. Analysis of the simultaneously obtained electrocardiogram
specifies the rhythm abnormalities which consist of an important
decrease in the atrio-ventricular conduction and changes in the
myocardial excitability. The cardiotoxicity
of FC 12 is assumed to affect passive or active transmembrane
ionic movements. Possible mechanisms are suggested here.
PMID: 6449983
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=150924&dopt=Abstract
C R Seances Soc Biol
Fil. 1978;172(2):337-47.
[Role of
endogenous adrenaline in cardiac arrhythmia induced by dichlorodifluoromethane
(FC 12) in mammals]
[Article in French]
Lessard
Y, Desbrousses S, Paulet G.
During the inhalation
of normally oxygenated gas mixtures containing light or middle
concentrations of FC 12, the presence of perfused epinephrine
is necessary to induce cardiac arrhythmia in rabbits and dogs.
The only inhalation of normally oxygenated gas mixtures containing
a very high concentration of FC 12 produces in rabbits and dogs
an important decrease in arterial pressure, tachycardia, a fall
in respiratory amplitude, an acceleration reflex of respiratory
frequency and cardiac arrhythmia. The same experiments in baro
and chemodenervated animals show that : respiratory depression
due to FC 12 still occurs, but not through the arterial chemoreceptors
; tachycardia has a reflex origin : barodenervation reveals the
negative chromotropic effect of FC 12 and increases the fall in
arterial pressure, mainly due to the negative inotropic effect
of FC 12 ; adrenaline is necessary for FC 12-induced arrhythmia
: barodenervation suppresses tachycardia due to the release of
endogenous epinephrine and abolishes any arrhythmia.
PMID: 150924
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=263946&dopt=Abstract
J Forensic Sci. 1977
Jan;22(1):34-9.
Electron
impact mass spectrometric detection of Freon in biological specimens.
Urich
RW, Wittenberg PH, Bowerman DL, Levisky JA, Pflug JL.
Freons from an aerosol
spray can were detected in the blood, liver, brain, and lung of
a 14-year-old girl who died after intentional inhalation. A headspace
mass spectrometric analytical technique was employed to detect
the fluorocarbons. The spectra from the specimens showed the presence
of m/e peaks at 101, 103, and 105 from the ion (CFCL2)+ which
arises from fragmentation of trichlorofluoromethane (Freon 11)
and dichlorodifluoromethane (Freon 12),
and peaks at 85 and 87 from the ion (CF2Cl)+ which arises from
fragmentation of dichlorodifluoromethane
(Freon 12). The technique presented here provides greater
specificity than previously reported analytical procedures for
the identification of these volatile toxic chemical compounds
in biological specimens.
PMID: 263946
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1011368&dopt=Abstract
Jpn Heart J. 1976
Nov;17(6):753-9.
Electrocardiographic
changes in rats after inhalation of dichlorotetrafluoroethane,
Arcton 114, C2Cl2F4.
Durakovic
Z, Stilinovic L, Bakran I Jr.
The effects of dichlorotetrafluoroethane,
Arcton 114, on the heart of rats were examined in 17 white rats.
The animals inhaled dichlorotetrafluoroethane for 1 or 1.5 min.
Severe electrocardiographic changes including marked bardycardia,
atrioventricular heart block of the second degree and complete
heart block were registered. Cardiac standstill appearing 11 to
31 min after inhalation was a death cause in all rats. These
results are similar to our previous results concerning the effects
of dichlorodifluoromethane (Arcton 12) on the heart of rats.
PMID: 1011368
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7144&dopt=Abstract
Am J Physiol. 1976
Jun;230(6):1701-7.
Effects
of hypoxia and Freon 12 on mechanics of cardiac contraction.
Kilen
SM, Harris WS.
Data are presented
which indicate that the mechanism of tension depression and subsequent
recovery from dichlorodifluoromethane (Freon 12), an aerosol gas
recently described as a potent cardiac depressant agent, differs
from that of hypoxia. To analyze these differences, 22 rat papillary
muscles, contracting isometrically in a myograph, were studied
during and subsequent to 15-min interventions of of hypoxia. Freon
12 with adequate oxygenation, or Freon 12 combined with hypoxia.
During each of the three interventions the developed force (F)
was markedly depressed, while peak shortening velocity (Vpm) was
selectively more depressed by Freon and Freon combined with hypoxia
than by hypoxia alone. While hypoxia shortened the time to peak
force (TTP) and one-half relaxation time (RT1/2) markedly, Freon
12 with adequate oxygenation slightly shortened RT1/2 (P is less
than 0.001) but failed to shorten TTP significantly. In contrast,
Freon 12 administered during hypoxia shortened TTP and RT1/2 significantly
(P is less than 0.001), more than did hypoxia or Freon 12 alone.
Posthypoxic prolongation of TTP and RT1/2 was not seen during
recovery from Freon 12. This prolongation was depressed during
recovery from Freon 12 given either during hypoxia or during recovery
from hypoxia. The results indicate that Freon 12 and hypoxia act
synergically, although the mechanisms through which they mediate
their actions on myocardial tissue are not identical.
PMID: 7144
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1209645&dopt=Abstract
Toxicology. 1975
Nov;5(2):127-38.
Hemodynamic
effects of aerosol propellants. I. Cardiac depression in the dog.
Simaan
JA, Aviado DM.
The inhalation of fluorocarbons
caused a depression of myocardial contractility, aortic hypotension,
a decrease in cardiac output and an increase in pulmonary vascular
resistance. The minimal concentrations that elicited these changes
are as follows: 1% trichlorofluoromethane (FC11); 2.5% dichlorotetrafluoroethane
(FC114); and 10% dichlorodifluoromethane
(FC12). Inhalation of 20% octafluorocyclobutane (FC318)
and difluoroethane (FC152a) did not influence these hemodynamic
parameters. As in previous comparisons, the most widely used aerosol
propellants are potentially cardiotoxic in the anesthetized dog.
PMID: 1209645
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1133731&dopt=Abstract
J Pharm Sci. 1975
Jun;64(6):1052-4.
Fluorocarbon
aerosol propellants V: binding interaction with human albumin.
Chiou
WL, Hsiao JH.
Binding of trichloromonofluoromethane,
dichlorodifluoromethane, and dichlorotetrafluoroethane
was studied in aqueous 5% human albumin solution, using the partition
coefficient method in sealed serum bottles. The partition coefficient
and the fraction of fluorocarbons bound were highly dependent
on fluorocarbon concentrations. The average binding sites per
molecule of albumin were 2.17, 0.30, and 0.42 and the binding
association constants were 1.11 X10-3, 1.73 X10-3, and 5.06X10-3
M-minus 1, respectively. At the lowest concentration studied,
62.3, 25.5, and 65.6% were found bound to albumin, respectively.
This appears to represent the first extensive study on any gas-albumin
interaction.
PMID: 1133731
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1132863&dopt=Abstract
Forensic Sci. 1975
Feb;5(1):53-9.
Determination
of fluorocarbon 11 and fluorocarbon 12 in post-mortem tissues:
a case report.
Poklis
A.
This report describes
the death of a teenager due to inhalation of fluorocarbon aerosol
propellants and presents a method for the determination of trichlorofluoromethane
(fluorocarbon 11) and dichlorodifluoromethane (fluorocarbon 12)
in post-mortem samples. The post-mortem blood and tissue levels
of these fluorocarbons are also presented. The
distribution of fluorocarbon 11 and fluorocarbon 12 is similar
to that observed in chloroform deaths.
PMID: 1132863
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=235808&dopt=Abstract
Toxicology. 1975;3(2):213-24.
Toxicity
of aerosol propellants in the respiratory and circulatory systems.
VI. Influence of cardiac and pulmonary vascular lesions in the
rat.
Doherty
RE, Aviado DM.
Three propellants were
selected for investigation in rats because of their non-uniform
effect in mice and monkeys. Trichlorofluoromethane (FC 11) provoked
arrhythmia in all three animal species, dichlorodifluoromethane
(FC 12) in monkeys and rats but not
in mice, and difluoroethane (FC 152a) only in rats. In
rats the alterations in heart rate and electrocardiographic pattern
during inhalation of these propellants are largely brought about
by release of catecholamines from the adrenal gland, because adrenalectomy
or prior injection of beta-adrenergic blocking drugs decreased
the incidence of cardiac effects. Rats that have pulmonary vascular
thrombosis or cardiac necrosis become more sensitive to proarrhythmic
activity of these propellants.
PMID: 235808
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=5083543&dopt=Abstract
J Pharmacol Exp Ther.
1972 Nov;183(2):245-55.
No
Abstract available
Direct
depression of myocardial contractility by the aerosol propellant
gas, dichlorodifluoromethane.
Kilen
SM, Harris WS.
PMID:
5083543 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=5080672&dopt=Abstract
Am Ind Hyg Assoc J.
1972 Apr;33(4):207-16.
No
Abstract available
Experimental
human exposures to fluorocarbon 12 (dichlorodifluoromethane).
Azar
A, Reinhardt CF, Maxfield ME, Smith PE Jr, Mullin LS.
PMID: 5080672
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=5727091&dopt=Abstract
Am Ind Hyg Assoc J.
1968 Sep-Oct;29(5):513-6.
No
Abstract available
Community
air quality guides. Dichlorodifluoromethane. (Difluorodichloromethane,
Fluorocarbon No. 12). CCl-2F2.
[No
authors listed]
PMID:
5727091 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=5743565&dopt=Abstract
J Forensic Sci. 1968
Jul;13(3):407-10.
No
Abstract available
A fatal
case involving trichloromonofluoromethane and dichlorodifluoromethane.
Baselt
RC, Cravey RH.
PMID: 5743565
[PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4962252&dopt=Abstract
Toxicol Appl Pharmacol.
1967 Mar;10(2):270-89.
No
Abstract available
Effects
on experimental animals of long-term inhalation of trichloroethylene,
carbon
tetrachloride, 1,1,1-trichloroethane, dichlorodifluoromethane,
and 1,1-dichloroethylene.
Prendergast
JA, Jones RA, Jenkins LJ Jr, Siegel J.
PMID:
4962252 [PubMed - indexed for MEDLINE]
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