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Persistent organic pollutants in 9/11 World Trade Center rescue workers: Reduction following detoxification

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Exposure to toxins following the September 11, 2001 attack on and collapse of the World Trade Center (WTC) is of particular concern given the ultra fine particulate dust cloud, high temperature combustion, and months-long fire. Firefighters, paramedics, police and sanitation crews are among the approximately 40000 personnel who labored for weeks and months on rescue and cleanup efforts. Many of the rescue workers have subsequently developed symptoms that remain unresolved with time. This study characterizes body burdens of polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans (PCDFs), and polychlorinated dioxins (PCDDs) in rescue workers and citizens exposed following the WTC collapse. Our research includes a pilot evaluation of a detoxification method aimed at reducing toxic burden. Many congeners were found at elevated levels, in ranges associated with occupational exposures. Post-detoxification testing revealed reductions in these congeners and despite the small study size, some reductions were statistically significant. Health symptoms completely resolved or were satisfactorily improved on completion of treatment. These results argue for a larger treatment study of this method and an overall treatment approach to address toxic burden.
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Persistent organic pollutants in 9/11 world trade center rescue
workers: Reduction following detoxification
James Dahlgren
a,*
, Marie Cecchini
b,1
, Harpreet Takhar
c,2
, Olaf Paepke
d,3
a
UCLA School of Medicine, Occupational Medicine, 2811 Wilshire Blvd. Suite 510, Santa Monica, CA, USA
b
Foundation for Advancements in Science and Education, 4801 Wilshire Blvd. Suite 215 Los Angeles, 90010 CA, USA
c
James Dahlgren Medical, 2811 Wilshire Blvd. Suite 510, Santa Monica, CA, USA
d
ERGO Laboratory, 22305 Hamburg, Germany
Accepted 26 May 2006
Abstract
Exposure to toxins following the September 11, 2001 attack on and collapse of the World Trade Center (WTC) is of particular con-
cern given the ultra fine particulate dust cloud, high temperature combustion, and months-long fire. Firefighters, paramedics, police and
sanitation crews are among the approximately 40000 personnel who labored for weeks and months on rescue and cleanup efforts. Many
of the rescue workers have subsequently developed symptoms that remain unresolved with time. This study characterizes body burdens
of polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans (PCDFs), and polychlorinated dioxins (PCDDs) in rescue workers
and citizens exposed following the WTC collapse. Our research includes a pilot evaluation of a detoxification method aimed at reducing
toxic burden. Many congeners were found at elevated levels, in ranges associated with occupational exposures. Post-detoxification testing
revealed reductions in these congeners and despite the small study size, some reductions were statistically significant. Health symptoms
completely resolved or were satisfactorily improved on completion of treatment. These results argue for a larger treatment study of this
method and an overall treatment approach to address toxic burden.
Ó2006 Published by Elsevier Ltd.
Keywords: Environment; Exposure; Dioxin; Dibenzofuran; PCB; Treatment
1. Introduction
Rescue workers present at the World Trade Center
(WTC) following the September 11, 2001 terrorist attacks
were exposed to large quantities of dust, smoke and fumes
from the building’s collapse and subsequent fire. The fire at
the WTC site burned for months. Firefighters, paramedics,
police and sanitation crews were among the approximately
40000 personnel who labored for weeks and months in the
immediate vicinity of the WTC. Personal Protective Equip-
ment (PPE) use was inconsistent (Kipen and Gochfeld,
2002), and contaminant exposure occurred in a number
of ways including dermal absorption and inhalation.
Many of the rescue workers developed persistent
coughs, headaches, memory disturbances and other symp-
toms while working on the site. Two and a half years later,
these symptoms persisted (Prezant et al., 2002). USEPA
measured levels of benzene, dioxins and polychlorinated
biphenyls (PCBs) in air and found these levels were ele-
vated in the weeks after the collapse. (Litten et al., 2003)
Dioxins slowly returned to normal background levels after
three months. (Litten et al., 2003) The New York (NY)
Department of Environmental Conservation (DEC) ana-
lyzed dust/ash samples collected nearby the WTC site.
0045-6535/$ - see front matter Ó2006 Published by Elsevier Ltd.
doi:10.1016/j.chemosphere.2006.05.127
*
Corresponding author. Tel.: +1 310 449 5525; fax: +1 310 449 5526.
E-mail addresses: Dahlgren@envirotoxicology.com (J. Dahlgren),
macecchini@comcast.net (M. Cecchini), htakhar@envirotoxicology.com
(H. Takhar), olaf.paepke@web.de (O. Paepke).
1
Tel.: +1 323 937 991.
2
Tel.: +1 310 449 5525.
3
Tel.: +49 40 69 70 96 23.
www.elsevier.com/locate/chemosphere
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The purpose of this study was two-fold: 1. To character-
ize body burdens of polychlorinated biphenyls (PCBs),
polychlorinated dibenzofurans (PCDFs), and polychlori-
nated dioxins (PCDDs) in exposed rescue workers and cit-
izen. 2. A pilot evaluation of a treatment method aimed at
reducing toxic burden.
2. Methods and materials
Seven men who were present at the WTC collapse and
involved in the rescue and cleanup effort received treatment
at Downtown Medical PC in April 2004 and agreed to par-
ticipate in this study. Five were employed by the New York
Fire Department (FDNY), one was a volunteer rescue
worker and one worked at the nearby at the NY Stock
Exchange. All were at the site the day of and several weeks
after the collapse when exposure would have been the high-
est. The rescue workers used little or no protective respira-
tory gear during the WTC cleanup and all currently live or
work in New York. The average age was 44 (range is 37–53).
These individuals volunteered to have their blood drawn
to measure the levels of polychlorinated biphenyls (PCBs),
polychlorinated dibenzofurans (PCDFs), and polychlori-
nated dioxins (PCDDs). Fifty milliliters of whole blood
was drawn in chemically cleaned glass containers prepared
by the analytic laboratory with anticoagulant with Teflon
Ò
tops containing no paper products. Blood was frozen and
sent frozen on dry ice to Germany for polychlorinated
dioxin and furan analysis at ERGO Laboratory, a World
Health Organization certified dioxin laboratory. Analysis
was performed by gas chromatography/high-resolution
mass spectrometry by methods previously described (Pa
¨pke
et al., 1989). Measured levels were converted to dioxin
toxic equivalents (TEQ) using the 1998 WHO toxic equiv-
alency factors (TEFs) (Van den Berg et al., 1998).
These subjects also participated in a series of testing
including thorough medical examination, structured health
and symptom questionnaires, and neurophysiological
testing.
All tests, evaluations, and sample collections were
repeated approximately one month after initial testing in
order to provide a comparison. Following the second per-
iod baseline evaluation, the study subjects enrolled in a
detoxification treatment regimen, which included exercise,
sauna bathing and vitamin and mineral supplements devel-
oped to reduce the adverse effects of chemical exposures.
(Schnare et al., 1982; Tretjak et al., 1990) On completion
of treatment, all subjects had their blood drawn for post-
treatment evaluation.
3. Results
The measured dioxin, dibenzofuran, and PCB congener
levels and TEQ for each subject before and after detoxifica-
tion is presented in Table 1. Prior to detoxification treat-
ment, five rescue workers (HB50605, WB5005, WB8008,
WB9009, WB13013) had elevated levels of 2,3,30,4,40-PeCB
(105), 2,30,4,4 0,5-PeCB (118) and/or 2,3,30,4,40,5-HxCB
(156). Patient H 5-0605 was a firefighter who we initially
tested in May 2003. Pre treatment, total mono-ortho PCB
blood levels ranged from 19 ppb to 404 ppb (WHO-TEQ
8.2–133.3) with a geometric mean of 41 ppb (WHO-TEQ
of 29.3). Pre-treatment, total non-ortho PCB blood levels
ranged from 43 ppt to 328 ppt (WHO-TEQ 3.9–111.9), with
a geometric mean of 81.8 ppt (WHO-TEQ of 13.1).
Table 2 displays the mean and median difference for
each congener following detoxification. The p-value is cal-
culated using the Wilcoxon singed-rank test, which is a
non-parametric test that uses ranks of the data consisting
of matched pairs. By using ranks, this test takes the magni-
tudes of the differences into account. Due to the small
sample size, we cannot assume normality of the data. A
non-parametric test is the best test for our study. The
means and medians listed in Table 2 are for the differ-
ences between the congener before and after detoxification.
Therefore, a positive score reflects a mean/median where
the average levels of dioxin, dibenzofuran and PCBs
dropped, while a negative score reflects where the average
levels increased.
Following detoxification, calculated WHO-TEQs for
mono-ortho PCB blood levels decreased by an average
65%, as shown in Fig. 1. Measured levels ranged from
15 ppb to 302 ppb (WHO-TEQ 3.6–133.3) with a geometric
mean of 32 ppb (WHO-TEQ of 8). Non-ortho WHO-TEQs
averaged a 57% decrease as shown in Fig. 2. Measured lev-
els ranged from 33 ppt to 229 ppt (WHO-TEQ 1.6–17).
Mono-ortho and non-ortho PCB levels in rescue workers
were measured twice in one month prior to detoxification to
determine the change in levels, or the lack thereof, with the
absence of treatment. As shown in Fig. 3, during this one-
month period of no treatment, PCB mean concentration
levels had a 4% insignificant increase. In contrast, all rescue
workers had measurable decreases in these PCBs follow-
ing treatment. Brominated dioxins, brominated dibenzo-
furans, and polybrominated diphenyl ether congeners were
at low levels or below the limit of detection (data not
shown).
Subjects reported a similar pattern of health complaints
and manifested symptoms including respiratory impair-
ment, mental/emotional distress (two met PTSD criteria),
decreased sensory systems, chronic muscle and joint
pain, gastrointestinal disorders, and skin rashes. These
were symptoms completely resolved or were satisfactorily
improved on completion of treatment. The neurophysio-
logical test results also improved. Fig. 4 shows the change
in mean severity of self-reported symptoms as measured by
a questionnaire.
4. Discussion
In view of the documented persistence of adverse health
effects in individuals exposed during the collapse of the
WTC, it is important to not only document symptoms
and possible causes but to identify workable treatment
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Table 1
Measured dioxin, dibenzofuran, and polychlorinated biphenyl levels
a
before and after treatment of WTC-exposed individuals, NY 2004
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modalities. The purpose of characterizing the levels of these
compounds was to determine whether compounds of this
class could be detected in this population this long after
exposure. Additionally, assuming detection, we wanted to
know whether their levels could be reduced by detoxifica-
tion treatment. It is useful to have a marker compound
for use in future studies that plan to evaluate the use of this
treatment method.
This was a complex exposure involving many different
compounds and under many different circumstances. Vari-
ous reports suggest that PCBs, PCDDs, PCDFs and bro-
minated flame retardants were not above background in
the dust at the WTC site when tested 5–6 days after the
attack. However the large volume of polybrominated
biphenyls and brominated diphenyl ethers could have led
to significant ambient exposure during the first few days
after the colapse (Lioy et al., 2002). These compounds have
Table 2
Mean and median differences for PCDDs, PCDFs and PCBs following
detoxification
Congener Mean
difference
Median
difference
(p-value)
2.3.7.8-Tetra-CDD 0.57 0.60 0.06
1.2.3.7.8-Penta-CDD 0.02 0.10 0.94
1.2.3.4.7.8-Hexa-CDD 0.14 0.51 0.56
1.2.3.6.7.8-Hexa-CDD 1.65 2.57 0.38
1.2.3.7.8.9-Hexa-CDD 0.37 0.61 0.44
1.2.3.4.6.7.8-Hepta-CDD 2.70 1.38 0.38
OCDD 10.48 0.99 0.69
2.3.7.8-Tetra-CDF 0.03 0.00 0.5
1.2.3.7.8-Penta-CDF 0.001 0.00 0.99
2.3.4.7.8-Penta-CDF .23 0.24 0.58
1.2.3.4.7.8-Hexa-CDF 0.32 0.37 0.47
1.2.3.6.7.8-Hexa-CDF 0.32 0.37 0.47
1.2.3.7.8.9-Hexa-CDF * * *
2.3.4.6.7.8-Hexa-CDF 0.15 0.75 0.44
1.2.3.4.6.7.8-Hepta-CDF 0.62 0.70 0.22
1.2.3.4.7.8.9-Hepta-CDF * *
OCDF * * *
3,30,4,40-TCB (77) 9.71 0.00 0.99
3,4,40,5-TCB (81) 1.66 2.19 0.16
3,30,4,40,5-PeCB (126) 4.39 1.31 0.69
3,30,4,40,5,50-HxCB (169) 2.76 0.73 0.47
2,3,30,4,40-PeCB (105) 2041.47 423.78 0.05
2,3,4,40,5-PeCB (114) 706.42 253.28 0.03
2,30,4,40,5-PeCB (118) 10568.20 3391.45 0.02
20,3,4,40,5-PeCB (123) 175.35 63.00 0.08
2,3,30,4,40,5-HxCB (156) 5644.41 2388.82 0.02
2,3,30,4,40,50-HxCB (157) 581.48 310.29 0.03
2,30,4,40,5,50-HxCB (167) 280.59 51.00 0.58
2,3,30,4,40,5,50-HpCB
(189)
6.55 2.96 0.99
Total PCDDs/PCDFs 12.86 3.03 0.94
Total non-ortho-PCBs 9.61 4.00 0.81
Total mono-ortho-PCBs 19640.66 4963.62 0.02
Wilcoxon Rank Test.
0
20
40
60
80
100
120
140
WTC002 WT C005 WTC006 WTC009 WT C011 WTC013 H50605
Patient ID
Total TEQ (WHO)
Pre-detox
Post-detox
Fig. 1. Changes in Blood Total WHO-TEQ Mono-Ortho PCB Levels
with Detoxification.
0
20
40
60
80
100
120
WTC002 WTC005 WTC006 WT C009 WTC011 WTC013 H50605
Patient ID
Total TEQ (WHO)
Pre-detox
Post-detox
Fig. 2. Changes in Total WHO-TEQ Non Ortho PCB Levels with
Detoxification.
-40
-30
-20
-10
0
10
20
30
40
WTC002 WTC005 WTC006 WT C009 WTC011 WTC013 H50605 Mean
Net Change in PCBs pg/g lipid based
Change Before Treatment
Change Following Treatment
Fig. 3. Change in Mono-Ortho PCB Levels with Treatment Compared
with One Month of No Treatment.
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long half-lives. (Schecter et al., 2002a; Schecter et al.,
2002b) It is unclear why PCBs but not PCDDs, PCDFs
or brominated flame retardant levels were elevated, despite
previous positive findings in chemical workers decades
after exposure. (Sullivan and Krieger, 1991) We can only
measure elevated levels of PCBs and dioxins in the human
body if uptake increases body burden significantly. For
comparison: the intake via food ranges between 50 and
100 pg TEQ/day. A typical air concentration may be at
0.05 pg TEQ/m
3
. Even at a 1000 times elevated air concen-
tration, 24 h inhalation (20 m
3
) adds ‘‘only’’ 1000 pg to the
body burden (equivalent to about 10 days additional
uptake from food).
The elevated concentrations of the PCB congeners
found in some rescue workers appear to be consistent with
the several dozen firefighters tested by FDNY and noted to
have elevated PCB levels above 12 PPB (as reported by
Medilabs, Valley Cottage NY – under contract with the
New York City Fire Department Medical Department.).
This level was found by using the Webb and McCall tech-
nique, which averages 6 ppb in the general population.
These levels are considerably higher than would be
expected in the general population, and consistent with lev-
els seen in occupational exposure to PCBs. (Edelman et al.,
2003) A particular firefighter (Patient HB50605) provided
us with results of two prior FDNY-ordered PCB tests
(based on Arochlor 1260, Webb and McCall technique).
Test results were 32 ppb on January 9th, 2002 and 13 ppb
on September 9th, 2002. He had his blood drawn and it
was analyzed for dioxin, dibenzofuran and PCB at ERGO
laboratory on May 2003 (Table 2). Using a more reliable
and sensitive technique, his levels measured 416 ppb
(WHO-TEQ 133.3). This firefighter (Patient H 5-0605)
had also worked on the day of and several days following
the collapse.
A study by Edelman et al, reports an unantici-
pated increase in heptachlorodibenzodioxin and hepta-
chlorodibenzofuran, associated with exposure from the
WTC collapse (Edelman et al., 2003). However, the authors
do not presume the exposure to be from the WTC collapse
alone.
The symptoms presented by the seven men in this group
matched the pattern seen in studies of WTC-exposed pop-
ulations. (Levin et al., 2004) A 2003 Mt. Sinai/NIOSH/
CDC analysis of 250 WTC screening program participants
document that approximately half of the sample had per-
sistent WTC-related pulmonary, ENT and/or mental
health symptoms that persisted a year following exposure
(Grandjean, 2003). The persistent symptomatology and
its successive improvements with detoxification is consis-
tent with medical records from the nearly 400 WTC-
exposed men and women who completed detoxification
treatment.
This pilot study is limited by its small sample size. No
relationships can be inferred between the PCB contamina-
tion found and the observed symptoms, or between reduc-
tion in these levels and the improvements following
treatment. However, it is interesting that studies evaluating
the adverse effects of high levels of PCB exposure commonly
list neurologic, (Chen et al., 1985; Chia and Chu, 1984)
immune and neuroendocrine effects (Carpenter, 1998), neu-
robehavioral effects, (Brown and Nixon, 1979; Schantz
et al., 2001) rashes and acne, nausea and other gastrointes-
tinal problems (Agency for Toxic Substances and Disease
Registry (ATSDR, 2000)). Occupational studies suggest
that exposure to PCBs may also cause irritation to the nose
and lungs, blood and liver changes, fatigue, and depression.
Furthermore, previous studies of PCB-exposed firefighters
have demonstrated neurologic symptom improvement on
completion of this treatment. (Kilburn et al., 1989) Prior
studies using this method of detoxification showed reduced
body burden of PCBs, PBBs and chlorinated pesticides
(Schnare et al., 1984). The data presented here will be used
for a larger subsequent study where correlations may be fur-
ther tested. Even three years after the WTC attacks, thou-
sands of exposure victims continue to have persistent
illness. New approaches to this public health predicament
are urgently needed.
Acknowledgements
We thank Toby Robinson for her technical and admin-
istrative support. We also thank Moon Young Oh, Alyssa
Tashiro, and Elaine Nitta for their help in revising the
manuscript.
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... One process investigated for detoxification in humans is the exploitation of the body's natural excretion through perspiration, with an assortment of toxicants shown to be excreted in this manner, such as metals (222), phthalates (223) and bisphenol A (224). Studies have reported that induced perspiration treatment in individuals with toxicant accumulation, specifically polychlorinated biphenyls (PCBs) compounds, results in a statistically significant reduction in body burden (225,226). Although promising, based on the limited available evidence, it seems that PFAS may not be readily excreted through sweat (227). ...
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Per-fluoroalkyl and polyfluoroalkyl substances (PFAS) are a diverse group of synthetic fluorinated chemicals used widely in industry and consumer products. Due to their extensive use and chemical stability, PFAS are ubiquitous environmental contaminants and as such, form an emerging risk factor for male reproductive health. The long half-lives of PFAS is of particular concern as the propensity to accumulate in biological systems prolong the time taken for excretion, taking years in many cases. Accordingly, there is mounting evidence supporting a negative association between PFAS exposure and an array of human health conditions. However, inconsistencies among epidemiological and experimental findings have hindered the ability to definitively link negative reproductive outcomes to specific PFAS exposure. This situation highlights the requirement for further investigation and the identification of reliable biological models that can inform health risks, allowing sensitive assessment of the spectrum of effects of PFAS exposure on humans. Here, we review the literature on the biological effects of PFAS exposure, with a specific focus on male reproduction, owing to its utility as a sentinel marker of general health. Indeed, male infertility has increasingly been shown to serve as an early indicator of a range of co-morbidities such as coronary, inflammatory, and metabolic diseases. It follows that adverse associations have been established between PFAS exposure and the incidence of testicular dysfunction, including pathologies such as testicular cancer and a reduction in semen quality. We also give consideration to the mechanisms that render the male reproductive tract vulnerable to PFAS mediated damage, and discuss novel remediation strategies to mitigate the negative impact of PFAS contamination and/or to ameliorate the PFAS load of exposed individuals.
... Surviving office employees, area residents, responders and volunteers who engaged in search and recovery and clean-up operations (all hereafter referred to as "WTC-affected individuals"), were exposed to severe psychological stressors, smoke, dust and debris. The thousands of individuals who remained on-site for search and recovery efforts as well as during the clean-up and rebuilding operations that followed were exposed to a toxic mix of contaminants and aerosolized particulate matter (PM) that was expelled from the burning buildings 4 . ...
Article
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On 11 September 2001 the World Trade Center (WTC) in New York was attacked by terrorists, causing the collapse of multiple buildings including the iconic 110-story ‘Twin Towers’. Thousands of people died that day from the collapse of the buildings, fires, falling from the buildings, falling debris, or other related accidents. Survivors of the attacks, those who worked in search and rescue during and after the buildings collapsed, and those working in recovery and clean-up operations were exposed to severe psychological stressors. Concurrently, these ‘WTC-affected’ individuals breathed and ingested a mixture of organic and particulate neurotoxins and pro-inflammogens generated as a result of the attack and building collapse. Twenty years later, researchers have documented neurocognitive and motor dysfunctions that resemble the typical features of neurodegenerative disease in some WTC responders at midlife. Cortical atrophy, which usually manifests later in life, has also been observed in this population. Evidence indicates that neurocognitive symptoms and corresponding brain atrophy are associated with both physical exposures at the WTC and chronic post-traumatic stress disorder, including regularly re-experiencing traumatic memories of the events while awake or during sleep. Despite these findings, little is understood about the long-term effects of these physical and mental exposures on the brain health of WTC-affected individuals, and the potential for neurocognitive disorders. Here, we review the existing evidence concerning neurological outcomes in WTC-affected individuals, with the aim of contextualizing this research for policymakers, researchers and clinicians and educating WTC-affected individuals and their friends and families. We conclude by providing a rationale and recommendations for monitoring the neurological health of WTC-affected individuals.
... 33 A study of seven World Trade Center rescue workers evaluated the effects of the Hubbard sauna detoxification method, including multiple hours of sauna a day for at least a month, vitamin and mineral supplements and a balanced lifestyle. 34 The study found a reduction of polychlorinated biphenyls (PCBs) in the blood of the participants while other contaminants like polychlorinated dibenzodioxins and polychlorinated dibenzofurans remained unchanged. Another study found urinary excretion of tetracycline decreased immediately after heat exposure, although the total amount of tetracycline in the 24-hour postexposure composite urine was similar to the control group, 35 demonstrating the need for analysis of extended composite or multiple time periods of urine analysis following sauna treatment to fully measure effectiveness. ...
Article
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Objective: Evaluate the effectiveness of firefighter exposure reduction interventions. Methods: Fireground interventions included use of self-contained breathing apparatus (SCBA) by engineers, entry team wash down, contaminated equipment isolation, and personnel showering and washing of gear upon return to station. Urinary polycyclic aromatic hydrocarbon metabolites (PAH-OHs) were measured after structural fire responses before and after intervention implementation. Separately, infrared sauna use following live-fire training was compared to standard post-fire care in a randomized trial. Results: The fireground interventions significantly reduced mean total urinary post-fire PAH-OHs in engineers (-40.4%, 95%CI -63.9%, -2.3%) and firefighters (-36.2%, 95%CI -56.7%, -6.0%) but not captains (-11.3% 95%CI -39.4%, 29.9%). Sauna treatment non-significantly reduced total mean PAH-OHs by -43.5% (95%CI -68.8%, 2.2%). Conclusions: The selected fireground interventions reduced urinary PAH-OHs in engineers and firefighters. Further evaluation of infrared sauna treatment is needed.
... Ideally, a future study would include biomarkers of GWI case status, such as serum autoantibodies [38], or other objective measures such as longer term follow-up changes in hippocampal microstructure [132]. Additionally, biomarkers should be obtained that would represent, in real time, the enhanced detoxification process such as changes in adipose, serum or skin lipids xenobiotic burden [51,52,[133][134][135]. Another potential tool is measurement of concentrations of small molecular weight compounds in both serum and sweat before, during and after the regimen [136][137][138]. ...
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Approximately 30% of the 700,000 US veterans of the 1990–1991 Persian Gulf War developed multiple persistent symptoms called Gulf War illness. While the etiology is uncertain, several toxic exposures including pesticides and chemical warfare agents have shown associations. There is no effective medical treatment. An intervention to enhance detoxification developed by Hubbard has improved quality of life and/or reduced body burdens in other cohorts. We evaluated its feasibility and efficacy in ill Gulf War (GW) veterans in a randomized, waitlist-controlled, pilot study at a community-based rehabilitation facility in the United States. Eligible participants (n = 32) were randomly assigned to the intervention (n = 22) or a four-week waitlist control (n = 10). The daily 4–6 week intervention consisted of exercise, sauna-induced sweating, crystalline nicotinic acid and other supplements. Primary outcomes included recruitment, retention and safety; and efficacy was measured via Veteran’s Short Form-36 (SF-36) quality of life, McGill pain, multidimensional fatigue inventory questionnaires and neuropsychological batteries. Scoring of outcomes was blinded. All 32 completed the trial and 21 completed 3-month follow-up. Mean SF-36 physical component summary score after the intervention was 6.9 (95% CI; −0.3, 14.2) points higher compared to waitlist control and 11 of 16 quality of life, pain and fatigue measures improved, with no serious adverse events. Most improvements were retained after 3 months. The Hubbard regimen was feasible, safe and might offer relief for symptoms of GW illness.
... 20 After the protocol's release in 1979, Schnare 21 described the regimen's safety and ability to reduce symptoms and improve mental functioning among individuals with a variety of chemical or illicit drug exposures. In nearly 40 years of application of this regimen to occupational or environmental exposures, studies have shown statistically significant reductions in human chemical pollutants, including polychlorinated biphenyls (PCBs) and dioxins, 22,23 and subsequent improvements in health. 24,25 Kilburn et al. 26 measured improvements in long-term memory, cognitive dysfunction and peripheral neuropathy among firefighters who completed sauna detoxification 6 months after PCB exposure from burning transformers. ...
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Objective: Protracted drug withdrawal symptoms can last months or years after drug cessation, often precipitating a return to substance misuse. We evaluated the safety and preliminary health benefits of a unique chemical exposure regimen based on exercise, sauna and therapeutic nutrients. Methods: This was a prospective evaluation of 109 individuals sequentially enrolled into a sauna detoxification component of a multi-modal, long-term residential substance abuse treatment centre. Results: Data from medical charts, client self-reports and Short Form Health Survey (SF-36) responses indicated that the Hubbard sauna detoxification method was well tolerated, with a 99% completion rate, including one human immunodeficiency virus and nine hepatitis C positive clients. There were no cases of dehydration, overhydration or heat illness. Statistically significant improvements were seen in both mental and physical SF-36 scores at regimen completion, as well as in Addiction Severity Index and Global Appraisal of Individual Needs Short Screener change scores at rehabilitation program discharge, compared with enrolment. Conclusions: The regimen lacked serious adverse events, had a very low discontinuation rate and high client-reported satisfaction. The SF-36 data indicated improved physical and emotional symptoms. Therefore, broader investigation of this sauna-based treatment regimen is warranted.
... A detailed treatment of firefighter exposure to fire emissions, including 9 scenarios, is given in [104]. Rescue and cleanup personnel working in the vicinity of the World Trade Center were exposed to elevated levels of benzene, PCDDs/PCDFs, and PCBs during the months after the building collapsed [13,105]. Ruokojärvi, et al.. have found similar compounds in simulated house fires [15]. ...
Technical Report
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Fire effluent is typically comprised of many compounds and particulates that are known to be harmful to people and the environment. The extent of contamination depends on the fire conditions, the fuel, the surrounding environment, and time. There are many stakeholder groups interested in understanding the effects of fire on the environment for a variety of reasons. This report and the accompanying spreadsheet can be used as a tool by a wide range of stakeholders as guidance toward the information necessary to plan activities related to assessment of damage before (pre-planning, life cycle assessment), during (response), and after (clean-up, research, lessons learned) a fire event. This report is essentially a literature review of the harmful effects of unwanted fire on the environment. The types of fires included are: structure fires (residential, commercial, industrial), vehicle fires (automobiles, lorries, trains), and wildland fires. Each of these types of fires may produce characteristic effluent and/or have specific traits that warrant individual consideration. Likewise, the actions of the emergency responders during a fire incident may affect the impact of the fire on the environment. Methodologies for determining the extent (both breadth and depth) of environmental contamination are presented. These methodologies include predictive models and physical measurements. A spreadsheet accompanies this report and is designed to allow data relating to expected eco-toxicants resulting from the fire types listed above to be searched by species, formula, chemical abstract service number, or environmental phase. The spreadsheet indicates which predictive or measurement method might be appropriate to use and includes discussion, when available, of the uncertainty of the results and any limitations to its use. This information is also included in the appendices of this report for completeness, however, the strength of the spreadsheet format is that it allows sorting of the data, which greatly enhances its usefulness but is not possible to do in the static tabular format of this report. The reader is therefore strongly encouraged to use the spreadsheet to search for and cross reference the most appropriate model(s) or measurement technique(s), or the eco-toxicants that may be present for the application of interest. A general discussion of life cycle assessment (LCA) as it applies to fire is also included in this report. Typical LCA does not consider fire as an end of life scenario, however, it is possible to use LCA thinking to compare the environmental effects of options such as the use of flame retardant chemicals, fire suppressant media or firefighting tactics. Finally, a gap analysis is presented wherein the completeness of the data collected from literature and fire testing reports is evaluated and areas that could benefit from additional research are identified.
Chapter
The building industry lacks a holistic and integrated method for assessing the possible human health risks attendant to using materials that have been verified as toxic. In particular, it lacks an open-source, interactive interface for measuring the health risks associated with sourcing, manufacturing, selecting, installing, using, maintaining, and disposing of building-based polymers. Because of their high degree of chemical synthesis, polymers are typically more toxic than wood, glass, or concrete; yet architects, engineers, builders, clients, and the general public remain poorly informed about the deadly accumulation of synthetic polymers that originate in the building industry and that pervade our air, water, and bodies. This question should be central to the very definition and practice of life-cycle assessment, and this chapter outlines a process for developing an industry-based life-cycle index of human health in building (LCI-HHB). After all, traditional LCAs are of little help to anyone not healthy enough to enjoy them.
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The worldwide prevalence of obesity has near tripled between 1975 and 2016. Diabetes was the direct cause of an estimated 1.6 million deaths in 2015. Diabetogens, otherwise known as toxicants that cause insulin resistance in animal models and humans as a result of pancreatic β-cell damage include the persistent organochlorine pesticides trans-nonachlor, oxychlordane, and DDE -the main metabolite of DDT, as well as another class of persistent organic pollutants, polychlorinated biphenyls (PCBs). Other toxicants that are now considered diabetogens: BPA, arsenic, phthalates, perfluorinates (PFOS), diethyl hexyl phthalate (DEHP), and dioxin (TCDD) are commonly found in the blood and urine in the CDC NHANES populations and presumed to also be commonly found in the U.S. population as a whole. A review of the literature on the risk for diabetes in epidemiologic studies considering these toxicants, challenges for clinicians using lab testing for these diabetogens, and the necessary interventions for lowering body burden of persistent toxicants are discussed.
Chapter
The building industry lacks a holistic and integrated method for assessing the possible human health risks attendant to using materials that have been verified as toxic. In particular, it lacks an open-source, interactive interface for measuring the health risks associated with sourcing, manufacturing, selecting, installing, using, maintaining, and disposing of building-based polymers. Because of their high degree of chemical synthesis, polymers are typically more toxic than wood, glass, or concrete; yet architects, engineers, builders, clients, and the general public remain poorly informed about the deadly accumulation of synthetic polymers that originate in the building industry and that pervade our air, water, and bodies. This question should be central to the very definition and practice of life-cycle assessment, and this chapter outlines a process for developing an industry-based life-cycle index of human health in building (LCI-HHB). After all, traditional LCAs are of little help to anyone not healthy enough to enjoy them.
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An expert meeting was organized by the World Health Organization (WHO) and held in Stockholm on 15-18 June 1997. The objective of this meeting was to derive consensus toxic equivalency factors (TEFs) for polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and dioxinlike polychlorinated biphenyls (PCBs) for both human, fish, and wildlife risk assessment. Based on existing literature data, TEFs were (re)evaluated and either revised (mammals) or established (fish and birds). A few mammalian WHO-TEFs were revised, including 1,2,3,7,8-pentachlorinated DD, octachlorinated DD, octachlorinated DF, and PCB 77. These mammalian TEFs are also considered applicable for humans and wild mammalian species. Furthermore, it was concluded that there was insufficient in viva evidence to continue the use of TEFs for some di-ortho PCBs, as suggested earlier by Ahlborg et al. [Chemosphere 28:1049-1067 (1994)]. In addition, TEFs for fish and birds were determined. The WHO working group attempted to harmonize TEFs across different taxa to the extent possible. However, total synchronization of TEFs was not feasible, as there were orders of a magnitude difference in TEFs between taxa for some compounds. In this respect, the absent or very low response of fish to mono-ortho PCBs is most noticeable compared to mammals and birds. Uncertainties that could compromise the TEF concept were also reviewed, including nonadditive interactions, differences in shape of the dose-response curve, and species responsiveness. In spite of these uncertainties, it was concluded that the TEF concept is still the most plausible and feasible approach for risk assessment of halogenated aromatic hydrocarbons with dioxinlike properties. VA:IBN
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With human exposure to environmental contaminants inevitable despite the best application of environmental laws and protection technologies, interest has grown in the potential to reduce the levels of contamination carried in the human host. This study demonstrates the promise of a comprehensive treatment for reduction of body burdens of polychlorinat ed and polybrominated biphenyis (PCB and PBB) and chlorinated pesticides. Adipose tissue concentrations were determined for seven individuals accidentally exposed to PBB. These patients underwent the detoxification treatment developed by Hubbard to eliminate fat-stored foreign compounds. Of the 16 organohalides examined, 13 were present in lower concentrations at post-treatmen t sampling. Seven of the 13 reductions were statistically significant; reductions ranged from 3.5 to 47.2 percent, with a mean reduction among the 16 chemicals of 21.3 percent (s.d. 17.1 percent). To determine whether reductions reflected movement to other body compartments or actual burden reduction, a post-treatment follow-up sample was taken four months later. Follow-up analysis showed a reduction in all 16 chemicals averaging 42.4 percent (s.d. 17.1 percent) and ranging from 10.1 to 65.9 percent. Ten of the 16 reductions were statistically significant. Future research stemming from this study should include further investigation of mobilization and excretion of xenobiotics in humans.
Article
Introduction Although polychlorinated biphenyls (PCBs) have been in use for 75 years and dioxin / furan contamination has been known for several decades, current knowledge on their adverse impacts on human health is limited. For example, the U.S. EPA's risk assessment for noncarcinogenic effects of PCBs is based on animal studies carried out with industrial Aroclor products. Their congener compositions substantially differ from the weathered mixture that humans are exposed to. A recent critique has focused on the validity of epidemiological findings. Thus, the American Council on Science and Health concluded: 1 '…there is no conclusive evidence that background PCB levels in the general population, or even the very high levels to which some occupational groups were exposed, have resulted in acute effects, increased cancer risk, "endocrine disruption", or widespread intellectual deterioration in children exposed to PCBs in utero.' Such controversy should inspire an assessment of the weaknesses associated with observational studies of PCB-exposed populations. Interpretation should take into account what can be reasonably demonstrated by such studies. These considerations may lead to improved study designs, and prudent decisions on preventive efforts should involve a cautious evaluation of the epidemiological data. This paper addresses some key issues in regard to exposure assessment, the temporal association between exposure and suspected outcomes, the possible impact of concomitant exposures, and the choice of appropriate outcome variables. Exposure Assessment Ideally, the exposure estimate should reflect the concentration of toxic agents at the vulnerable target. The main concern of the analytical chemist is to optimize the analytical quality, i.e., both precision and accuracy. While this issue is crucial, the validity of the results when applied in an epidemiological study must also consider specimen characteristics, e.g., whether a blood sample was taken from fasting subjects, or whether the sample reflects the maternal or the fetal circulation. Fortunately, when the result is expressed on a lipid basis, PCB concentrations are similar in maternal and cord serum (Figure 1, left). However, the correlation shows more scatter when one sample is assessed on a wet-weight basis (Figure 1, right).
Article
The direct and protracted nature of the rescue and recovery workers and volunteers’ exposure to the aftermath of the 9/11 attacks differentiates these persons from the general population.⁷ These responders are unlike previous populations of rescue workers⁸ because of the heterogeneity of their occupations (e.g., construction trades, utilities and sanitation workers, and first responders) and the documented health effects of their WTC work. The proportion of those meeting PCL threshold scores² for posttraumatic stress in the predominantly male sample is approximately four times the 5% reported lifetime prevalence of PTSD in the general male population.⁶ The point prevalences of approximately 6%, respectively, for panic and generalized anxiety symptoms represent a two- to fourfold increase, compared with the 12-month prevalences of 2% and 3%, respectively, reported in the general population.⁹ However, depression was detected at a prevalence of 6%, nearly half the 12-month prevalence of 10% reported in the general population.⁹ The point prevalence of alcohol abuse and dependence of nearly 10% documented by CAGE suggests rates at least as high as the 12-month prevalence of 9.7% reported in the general population.⁹
Article
Results of determination of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) in blood of a group of 10 persons with no declared exposure are presented. Each of the collected 40-ml blood samples was diluted with water, partitioned on Chem-Elut (modified Silicagel) and eluted with hexane / isopropanol. After evaporation and weight determination, the residue was subjected to a multicolumn system clean-up involving carbon on glass fibre. The final extract was dissolved in 10 μl toluene and analysed with HRGC/MS. The detection limit for 2.3.7.8-Tetra-CDD was normally 1 - 2 pg/g blood lipid. The levels measured are discussed and compared with the results of similar investigations in Germany.
Article
Twenty-one persons exposed to polybrominated biphenyls (PBB) were compared with hospital volunteers on a battery of tests measuring memory, motor strength and coordination, cortical-sensory perception, personality, and higher cognitive functioning. Patients exposed to PBB were selected for this study only if they had persistent medical complaints. The PBB adipose levels did not correlate with performance on any test in the battery. The two groups did differ on the Minnesota Multiphasic Personality Inventory, suggesting an adjustment reaction with depressive symptoms and somatizing defenses. Persons exposed to PBB were also impaired relative to control subjects on tests of prose recall, short-term memory, concentration, and cognitive flexibility. However, these differences vanished when group differences on education and personality were statistically held constant. The selective admission criteria for this study limit the generalizability of these findings. (JAMA 242:523-527, 1979)
Article
1. A detoxification trial was administered to a female worker from a capacitor factory who had been exposed to polychlorinated biphenyls (PCBs) and other lipophilic industrial chemicals. 2. The patient presented with severe abdominal complaints, chloracne, liver abnormalities, and a spontaneous nipple discharge of approximately 50 ml d ⁻¹ . 3. PCB levels were high in adipose tissue (102 mg kg ⁻¹ ), serum, (512 μg 1-1), skin lipids (66.3 mg kg ⁻¹ ), and in the nipple discharge (712 μg I ⁻¹ ). 4. The patient's history, the medical evaluation and prior unsuccessful symptomatic treatments were indicative of consequences elicited by occupational exposure to chemicals. 5. Detoxification treatment reduced the PCB levels in adipose tissue to 37.4 mg kg ⁻¹ and in serum to 261 μg 1-1, a 63% and 49% reduction, respectively. 6. The nipple discharge ceased and the symptoms improved. 7. Excretion of intact PCBs in sebum was appreciable before treatment and was enhanced by up to five-fold during detoxification. 8. This therapeutic approach appears promising for cases involving occupational exposure to lipophilic chemicals.
Article
Fourteen firemen exposed to polychlorinated biphenyls (PCBs) and their byproducts generated in a transformer fire and explosion had neurophysiological and neuropsychological tests 6 mo after the fire. They were re-studied 6 wk later after undergoing 2-3 wk of an experimental detoxification program consisting of medically supervised diet, exercise, and sauna. A case-control comparison with firemen matched from the same department, but who did not participate in controlling the transformer fire, had shown significant impairment of memory for stories, visual images, and digits backwards. Cognitive function was impaired for block design, identifying embedded figures, and design association and recognition using Culture Fair. Making of trails and choice reaction time, which measured cognitive function and perceptual motor speed, were also impaired. These signs of protracted neurobehavioral impairment were attributed to PCBs and heat-produced byproducts. No relationship, however, was found between the firemen's serum or fat levels of PCBs as Arochlor 1248 and their type or degree of neurobehavioral impairment. Retesting following the detoxification program showed significantly improved scores on: three memory tests, block design, trails B, and embedded figures. Thus, there was significant reversibility of impairment after the detoxification interval. However self-appraisal scores for depression, anger, and fatigue--which were initially elevated--and for vigor--which was reduced--did not change across this interval.
Article
In 1979 in Taiwan, more than 2000 people were poisoned with rice cooking oil contaminated with polychlorinated biphenyls (PCB). One hundred ten patients were studied within one year of the exposure. The blood PCB levels were 39.3 +/- 16.6 ppb. The blood levels of the PCB derivatives, polychlorinated quaterphenyls (PCQ) and polychlorinated dibenzofurans (PCDF), were 8.6 +/- 4.8 and 0.076 +/- 0.038 ppb, respectively. Both the sensory and motor nerve conduction velocities (NCV) of the patients were significantly lower than the control. Abnormal slowing of sensory NCV was found in 43.6% and abnormal slowing of motor NCV was seen in 21.8%. Patients who had higher PCQ blood levels had significantly slower median nerve sensory NCV than those with lower PCQ levels. Patients with higher PCB blood levels had significantly slower peroneal nerve motor NCV than those with lower PCB levels.