Post on 16-Feb-2021
Endocrine disruption of personal care products &
related mechanisms
Kyungho Choi
August 19, 2015
School of Public Health, Seoul National University
Contents
• Introducing
– SNU, School, Department
– My laboratory and research interests
• Endocrine disrupting chemicals (EDCs)
– Importance in public health
– EDCs
– Case introduction and future studies
To me and my Korean fellows
• Thailand – Thai smile
– King Rama 9
– Korean War of 1950-3
• Mahidol University – No 1 in medicine and public health
– Great international program
– Smart students
Seoul National University in Winter
SNU in wikipedia
• A national research university located in Seoul, Korea. Founded in 1946, SNU has served as a model for many national and public universities in Korea. Today SNU comprises sixteen colleges and six professional schools, and about 30,000 students.
• QS World University Rankings (2014/15) considered it 31st in the world and 3rd in Asia, whilst it was 4th in the independent regional QS Asian University Rankings (2013).The university was 4th in Asia and 50th in the world by the 2014-15 Times Higher Education World University Rankings when its World Reputation Rankings considered it to be 26th globally. In 2009, the Ecole des Mines de Paris - MINES Paris Tech reported that Seoul National is ranked 5th in the world in terms of the number of alumni holding CEO positions in Fortune 500 enterprises.
https://en.wikipedia.org/wiki/QS_World_University_Rankingshttps://en.wikipedia.org/wiki/QS_Asian_University_Rankingshttps://en.wikipedia.org/wiki/QS_Asian_University_Rankingshttps://en.wikipedia.org/wiki/Times_Higher_Education_World_University_Rankingshttps://en.wikipedia.org/wiki/Times_Higher_Education_World_University_Rankingshttps://en.wikipedia.org/wiki/World_Reputation_Rankingshttp://en.wikipedia.org/wiki/Fortune_500
School of Public Health
Small but strong school!
• Alumni
– Shin, Young-soo (Regional Director WPRO)
– Kim, Hwa-joong (former Minister Ministry of Health)
Environmental Health within SPH
Bioinformatics
Health
Statistics
Demography
Environ
Health
Nutrition
Epidemiology
Mol/Genetic
Epidemiology
Disease
Epidemiology
Biostatistics Epidemiology
Hlth Behavior
Public Hlth
Policy
Dept of Environmental Health
Environ Toxicology
Exposure Sci Indoor Environ Qual Occup
Hygiene
Environ/Occup Medicine
Environ Hlth Microbiology
Environ Chem & Monitoring
Air Pollution & Climate Change
Biomonitoring
Environ Hlth Engineering
Environmental Health within Dept
Envion Monit Exp Assessmt
Biomonitoring
Risk Assessmt
Toxicology
Epidemiology
Health effect
Chemicals and
Microbials
Environmental Toxicology Laboratory (ETL)
• 1 Research Prof, 1 postdoc
• 4 PhD students, 6 MPH students
• 1 Researcher
• 1 Administrative staff
Research interest
• Environmental toxicology – Fish and cell lines of human and animal origins
– Endocrine, genotoxicity, oxidative stress related mechanisms
– POPs, EDCs, pharmaceuticals
• Exposure and risk assessment, epidemiology – Endocrine disrupting chemicals
– Pharmaceuticals and personal care products
Current research interest
• Linking chemicals and adverse health effects using – Observational studies in human population
– Laboratory toxicological studies using cells and animals
Adding biological plausibility on the observed associations
EDCs and Environmental Health
Environmental impacts on health
• Environmental factors cause >25% of global burden of disease
• About 3 million children under 5 die due to environmentally linked diseases
15 Source Neira M, WHO
Environmental impacts on health
16 Source Neira M, WHO
Environmental burden of disease is highest in the poorest countries
Major global environ health risks
17 Source Neira M, WHO
• Poor hygiene and sanitation
• Household water insecurity
• Disease vectors
• Chemical hazards
• Injuries and accidents
• Air pollution indoor/outdoor
• Emerging issues Global climate change Ozone depletion Persistent organic pollutants Obesity Electrical and electronic wastes Endocrine disruption
Endocrine disrupting chemicals
• WHO/IPCS 202
• Exogenous substance or mixture that alters function(s) of the endocrine system and consequently causes adverse effects in an intact organism, or its progeny, or (sub)populations
EDCs are global concern
20
(WHO/UNEP, 2012)
Chapter 1. General aspects on endocrine disruption Chapter 2. Evidence for endocrine disruption in humans and wildlife
• Female/Male reproduction health • Sex ratio • Thyroid-related disorders • Neurodevelopmental disorders in children and wildlife • Hormone-related cancers • Adrenal disorders in humans and wildlife • Bone disorders • Metabolic disorders • Immune function and diseases in humans and wildlife • Population declines
Chapter 3. Human and wildlife exposures to EDCs
Concerns on endocrine disrupting effects of chemicals are of worldwide concern
Endocrine related diseases
• Sperm quality decrease in 40% male (several EU countries) -> infertility?
• Malformation of male genitals – Cryptorchidism, hypospadias
• Pregnancy and delivery
• Endocrine cancers
• Precocious puberty
• Obesity and T2 diabetes
EDCs
• Phenols-APs, BPA • Phthalates • POPs
– DDTs, OCPs, PCBs – PFCs, PBDEs
• Metals – Pb, Hg, Cd, As
• Pharmaceuticals – NSAIDs
• and more
Regulating sex hormone balances
Modes of action - nuclear receptor mediated
effect
- hormone regulation
Regulating thyroid hormone balances
2015-08-24 24
(1) DDT, PCBs (2) PCBs,FRs (3) PBDEs,chlordane (4) PCBs, HCB, FRs (5) (6) PCBs
(1) Synthesis of THs
(2) Transport proteins
(3) Cellular uptake
(4) The TH receptor
(5) Iodothyronine deiodinases
(6) Metabolism in the liver
(Lyn et al., 2009; Boas et al., 2012)
Case studies on consumer chemicals
• Sex hormone – disruption and reproduction effects of
benzophenone 3
• Thyroid hormone – disruption by alternative flame retardants
• Epidemiological observations – of thyroid hormone disruption by consumer
chemicals
Sex hormone disruptions by environmental chemicals and their
mechanisms Benzophenone-3
(Kim et al., Aquat Toxicol, 2014)
Benzophenone-3 (BP-3)
• Widely used UV filter - Employed in sunscreens and various cosmetic products
- To protect products or human skins from the deleterious effects of UV
light
Benzopheone-3 (BP-3)
BP-3 in aquatic environment
• Surface waters - Both direct (recreational activities) and indirect (via WWTPs) inputs
- Up to 125 ng/L in a recreational lake in Switzerland (Poiger et al., 2004)
• Wastewater influent and effluent
• Sediments and soil
• Biota like fish
(Diaz-Cruz et al. Trends Anal Chem. 2008)
Direct input and indirect input of UV filters such as BP-3
BP-3 in human samples
• Frequently detected in urines worldwidebreastmilk, and
cord blood
(Kim et al. Environ Int, in revision)
Endocrine disrupting potential of BP-3
• in vitro - MCF-7 cell proliferation
- YES assay: weak estrogenic, strong anti-
estrogenic and anti-androgenic activities
(Schlumpf et al. Environ Health Perspect. 2001) (Coronado et al. Aquat Toxicol. 2008) (Fent et al. Chimia. 2008)
• In fish - VTG induction: varies among species
- Damage on reproduction and hatchability in Japanese medaka following
21 d exposure
Metabolism of BP-3
• Mainly metabolized into benzophenone-1 (BP-1)
- In rat, fish, and human (Bluthgen et al., 2012; Okereke et al., 1993; Wang and Kannan, 2013)
• BP-1 has greater estrogenic receptor binding activity than BP-3 in vitro (Kunz et al., 2006; Molina-Molina et al., 2008)
2-hydroxy-4-methoxybenzophenone (BP-3) 2,4-dihydroxybenzophenone (BP-1)
-50.00
0.00
50.00
100.00
150.00
-3.00 -1.00 1.00
% E
2-m
ax
Log μM
BP3
BP1
E2
(BP-3 and BP-1 in MVLN assay, preliminary data)
Research Gap
• Ecotoxicological information of long-term exposure to BP-3 and its metabolites is limited
• Underlying mechanism of the effects is still unclear - Currently available mostly on endocrine disrupting potential of BP-3
based on the receptor binding affinities
•
•
Study design
• Test organism: Japanese medaka - 28 d exposure of adult fish pairs
- F1 early life stage (ELS) fish exposure until 30 dph
• Observation/Endpoints
14 d adult fish exposure
study
- plasma vitellogenin (VTG) and sex hormones (E2, T)
- liver and gonadal mRNA expression
14 d mating study - # of eggs/female/day
F1 ELS toxicity study - hatchability
- weight, length, and condition factor
Measured concentrations
• Low recovery of BP-3 (17 ~ 36% nominal conc) • low solubility (0.005% DMSO); metabolism
• Metabolism to BP-1 • both adult and juvenile fish can biotransform BP-3 to BP-1
Nominal
conc.
Adult Japanese medaka exposure F1 early life stage exposure
BP-3 BP-1 BP-3 BP-1
0 h 48 h Median 0 h 48 h Median 0 h 48 h Median 0 h 48 h Median
Water ctrl
14 d adult fish exposure (Day 0-14)
• Plasma E2 • Decreasing trend but no
significance
• Plasma T • Significant increase in
males
• E2/T ratio • Significant decrease in
both male and female
0 4.7 8.4 26 90
Te
sto
ste
ron
e
(co
ntr
ol=
1)
0
1
2
3
4
5
6
7
Male
0 4.7 8.4 26 90
17e
str
ad
iol
(co
ntr
ol=
1)
0.0
0.5
1.0
1.5
2.0
2.5
Female
0 4.7 8.4 26 90
0 4.7 8.4 26 90
0 4.7 8.4 26 90
E2
/T r
atio
(co
ntr
ol=
1)
0.0
0.5
1.0
1.5
2.0
2.5
0 4.7 8.4 26 90
*
= -0.005p = 0.191
= -0.009p = 0.075
= 0.033p = 0.019
= 0.006p = 0.120
= -0.008p = 0.014
= -0.011p = 0.027
*
(A)
(B)
(C)
Nominal conc. 0 15 50 150 500 0 15 50 150 500
Measured conc. g/L
g/L
g/L
14 d adult fish exposure (Day 0-14)
• gonadal mRNA expression • overall down-regulations of several steroidogenic genes
• including cyp19a (E2 → T) and hsd17b3 (sex hormone production) genes
0 4.7 8.4 26 90
cyp17 m
RN
A fold
change
0.0
0.5
1.0
1.5
2.0
2.5
Male
0 4.7 8.4 26 90
sta
r m
RN
A fold
change
0.0
0.5
1.0
1.5
2.0Female
0 4.7 8.4 26 90
0 4.7 8.4 26 90
0 4.7 8.4 26 90
hsd17b3
mR
NA
fold
change
0.0
0.5
1.0
1.5
2.0
0 4.7 8.4 26 90
= -0.004p = 0.122
= -0.010p = 0.000
= -0.008p = 0.014
= -0.005p = 0.004
= -0.003p = 0.190
= -0.006p = 0.001
*
g/L
0 4.7 8.4 26 90
hsd3b m
RN
A fold
change
0.0
0.5
1.0
1.5
2.0
Male
0 4.7 8.4 26 90
cyp11a m
RN
A fold
change
0.0
0.5
1.0
1.5
2.0
Female
0 4.7 8.4 26 90
0 4.7 8.4 26 90
0 4.7 8.4 26 90
cyp19a
mR
NA
fold
change
0.0
0.5
1.0
1.5
2.0
0 4.7 8.4 26 90
= -0.007p = 0.032
= -0.005p = 0.029
= -0.006p = 0.007
= -0.009p = 0.004
= -0.005p = 0.034
= -0.007p = 0.001
g/L
*
*
g/L
g/L g/L
g/L
***
*
*******
(A) (B)
(C) (D)
(E) (F)
Nominal conc. 0 15 50 150 500 0 15 50 150 500
Measured conc.
Nominal conc. 0 15 50 150 500 0 15 50 150 500
Measured conc.
14 d adult fish exposure (Day 0-14)
• steroidogenesis pathway
Cholesterol
Pregnenolone
17α-OH-pregenolone
DHEA
Progesterone
17α-OH-Progesterone
Androstendeione
11-Deoxy-
corticosterone
11-Deoxycortisol
Testosterone (T)
Estreone
Corticosterone
Cortisol 17β-estradiol (E2)
Aldosterone
STAR,
CYP11A
CYP17
CYP17
CYP17
HSD17B
CYP19A
CYP17
CYP17
HSD3B
CYP11B
CYP11B
HSD17B
CYP21 CYP21
HSD3B
CYP11B
HSD3B
CYP19A
14 d adult fish exposure (Day 0-14)
• plasma vitellogenin (VTG) level - significant VTG induction
in male fish
- VTG : an estrogen dependent protein
- same results in transcripts in liver of male fish (data not shown)
• increase of VTG conc? - vs E2/T ratios significantly decreased
- biotransformation of BP-1 being responsible? BP-1 with greater ER binding affinity
Male
0 4.7 8.4 26 90
pla
sm
a V
TG
(conto
l=1)
0
3000
4000
5000
Female
0 4.7 8.4 26 90
= 34.22p = 0.000
= 0.007p = 0.132*
g/L
Nominal conc. 0 15 50 150 500 0 15 50 150 500
Measured conc.
Mating study (Day 15-28)
• Egg production per female during Day 22-28 - significantly reduced at 26 BP-3 μg/L (day 22 to 28 d)
- 20 fold lower than those reported in Coronado et al. (620 μg/L, 2008)
• Cumulative number of eggs during Day 22-28 - significant decreases at 26 μg/L observed from Day 26
22 23 24 25 26 27 28
Cu
mu
lative
eg
g n
um
be
r
0
10
20
30
40
50
60 solvent ctrl
4.7 mg/L BP-3
8.4 mg/L BP-3
26 mg/L BP-3
0 4.7 8.4 26 90
No
. o
f e
gg
s/f
em
ale
/da
y
0
2
4
6
8
10= -0.087p = 0.011
g/L
**
day
***
*
(A) (B)
†
Nominal conc. 0 15 50 150 500
Measured conc.
At 90 μg/L, serious mortality was observed in both sex fish and no eggs were produced.
4.7 ug/L BP-3
8.4 ug/L BP-3
26 ug/L BP-3
F1 ELS toxicity study
• Hatching of F1 eggs - At 30 μg/L (nominal 150 μg/L) BP-3, relatively lesser hatchability
(88.3 %)
• Growth following subsequent 30 d exposure of F1 fish - Condition factor in significant decreasing trend
- Later life stage effects?
†
Measured
Conc.
Nominal
Conc. n
Hatchability
(%)
Solvent ctrl 5 96.7± 2.0
5.4 µg/L 15 7 96.4 ± 1.7
12 µg/L 50 7 98.8 ± 1.2
30 µg/L 150 5 88.3 ± 5.7
n Number of replicates; n=12 eggs per each replicate
Hatchability = Number of hatched eggs/total eggs x 100
condition factor, K=100ⅹ[total weight (g)]/total length (cm3)]
0 5 12 30
9
10
11
12
13
14
g/L
Juvenile
fis
h length
(m
m)
Juvenile
fis
h d
ry w
eig
ht
(mg)
0 5 12 30
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
0 5 12 30
0.14
0.16
0.18
0.20
0.22
0.24
0.26
Conditio
n F
acto
r
= 0.037
r2 = 0.216
p for trend = 0.216
= 0.001
r2 = 0.000
p for trend = 0.982
= -0.002
r2 = 0.292
p for trend = 0.014
(A) (B) (C)
Nominal conc. 0 15 50 150
Measured conc.
0 15 50 150 0 15 50 150
Length Dry weight Condition Factora
Summary of BP-3 study
• Biotransformation to BP-1 in both adult and fry fish • BP-3 is transformed into BP-1 in both adult and fry Japanese medaka
• Sex hormone and reproduction effects • BP-3 (and its metabolite BP-1) affects sex endocrinology (in both
transcripts and hormones) and reproduction of fish at as low as 26
μg/L
• Lowered condition factor of F1 juveniles • Two generation exposure led to lowered condition factors of F1
juvenile fish
• Future studies • Implication in other organisms including humans
• Longer term exposure in later life stages of F1 fish including
reproduction and growth performances
Thyroid hormone disruptions by environmental chemicals
Alternative flame retardants
Alternative chemicals replacing PBDEs, flame retardants
• After phaseout of commercial mixture of PBDEs, organophosphate (OP) flame retardants, and other chemicals (FireMaster 550, Dechlorane plus etc) have replaced
Experimental models
in vivo organism
Zebrafish embryo/larva
0 hpf embryo 168 hpf larva 48-72 hpf
(hpf, hours post-fertilization)
- Developmental toxicity - Hormone and gene analysis
Pituitary gland GH3 cell (Rat) Central regulation
Thyroid gland FRTL-5 cell (Rat) Thyroid hormone Synthesis/Regulation
TSH
T3, T4
in vitro cell lines
- Gene analysis
Triphenyl phosphate (Kim et al., Aquat Toxicol, 2015)
• Triphenyl phosphate (TPP)
– Flame retardants added to carpets, furniture, and electronics
– Thyroid hormone disrupting potentials
• similar compounds : PBDEs, TDCPP
• In vitro experimental studies – Gene expression changes in GH3 and FRTL-5 cells
45
tshβ trα trβ dio1 dio2 nis tg tpo tshr pax8 nkx2.1
GH3 cells FRTL-5 cells
Zebrafish larvae after TPP exposure
46
• TH synthesis increased; genes for hormone synthesis are upregulated
• Malformation rate was increased T4 T3
TBB and TBPH (Jung JE., MPH Thesis, 2015)
• Alternative flame retardants replacing PBDEs
– Wire, cable insulation, carpet, furniture foam, wall coverings, coated fabrics, and adhesive
• Endocrine disruption potentials – TBPH structurally similar to phthalates
– House dust TBPH is positively associated with
human plasma T3 (Johnson et al., 2013)
– Sex and thyroid hormone disruption by TBB or
TBPH in experimental studies (Patisaul et al., 2012, Saunders et al., 2013, Mankidy et al., 2014)
47
– Endocrine disruption potential (Johnson et al., 2013; Saunders et al., 2013)
GH3 and FRTL5 cells after TBB and TBPH exposure
• TBB and TBPH act like T3 or TSH in both cell lines
48
tshβ trα trβ dio1 dio2
Fold
ch
an
ge
0.0
0.5
1.0
1.5
2.08.0
8.5
9.0
9.5
10.0 T3
Solvent control
0.05 mg/L
0.5 mg/L
5 mg/L
50 mg/L
*
*
*
**
*
*
tshβ trα trβ dio1 dio2
Fold
ch
an
ge
0.0
0.5
1.0
1.5
2.08.0
8.5
9.0
9.5
10.0T3
Solvent control
0.1 mg/L
1 mg/L
10 mg/L
100 mg/L
*
*
*
*
*
*
*
*
*
*
nis tg tpo pax8 nkx2.1
Fold
ch
an
ge
0
1
2
3
4
20
22
24
26
28TSH
Solvent control
0.5 mg/L
5 mg/L
50 mg/L*
*
*
**
* * * **
nis tg tpo pax8 nkx2.1
Fold
ch
an
ge
0
1
2
28
TSH
Solvent control
0.01 mg/L
0.1 mg/L
1 mg/L TBPH
*
*
* **
**
*
TBB TBPH
GH3
FRTL-5
Zebrafish larvae after TBB and TBPH exposure
• Different response – TBB increases T3 concentrations
– TBPH decreases both T4 and T3 concentrations
• Mechanisms involving targets other than pituitary and thyroid gland? Or metabolites?
49
T4 c
on
ten
t (n
g/g
)
0
10
20
30
40
T3 c
on
ten
t (n
g/g
)
0
1
2
39
10
11
12
*
0
*
= -0.017
r2 = 0.185p = 0.066
0.05 0.5 5 50 0.05 0.5 5 50
= -0.241
r2 = 0.188p = 0.058
0
T4 c
on
ten
t (n
g/g
)
0
10
20
30
40
T3 c
on
ten
t (n
g/g
)
0
2
4
6
8
10
12= 0.071
r2 = 0.170p = 0.079
0 0.05 0.5 5 50 0.05 0.5 5 500
TBB exposure TBPH exposure
Dechlorane Plus (DP) (Kang et al. in review)
• Replacement for usage of decaBDE
– Electric devices, textile, building, and construction
• Previous information on toxicity of DP
– Oxidative stress and oxidative DNA damage in liver (Li et al., 2013; Wu et al., 2012)
– Evidence of thyroid hormone disruption from an epidemiology study (Ben et al., 2014)
50
Exposure design
• Male adult zebrafish
– Low water solubility of DP (4.4x10-8 mg/L)
→ oral gavage feeding
51
oral gavage feeding Corn oil, 0.3, 1, or
3 μg/g of DP-25
0 day
6 day
sampling
2 day
Blood (serum) Hormone concentration (T4, T3)
Brain, liver, and testis
mRNA: thyroid and sex steroid hormone related gene
Results of PO exposure to DP
• Increase of T4 – Increase of plasma T4
– Genes stimulating thyroid hormone synthesis were upregulated
52
DP-25 (g/g zebrafish wet weight)
0 0.3 1 3
rela
tiv
e g
en
e e
xp
ress
ion
0.0
0.5
1.0
1.5
2.0
0 0.3 1 3n=3 n=3 n=3 n=3 n=3 n=3 n=3 n=3
T4 T3
(H. Kang et al. in preparation)
DP-25 (g/g zebrafish wet weight)
0 0.3 1 3
rela
tive g
ene e
xpre
ssio
n
0
1
2
3
4
5
0 0.3 1 3n=5 n=5 n=5 n=5 n=5 n=5 n=5 n=5
crh tsh
*
*
Summary
• Many alternative flame retardants are thyroid disrupting chemicals
• Using both in vitro and in vivo approaches, thyroid disrupting potential of alternative chemicals can be effectively screened
• Further observations in human population to follow
53
– Confirmation in long term low dose exposure should follow
Thyroid hormone disruptions by environmental chemicals among
general population Epidemiological observations
Previous studies
• Environmental phenols and thyroid in NHANES 2007-2008
55
BP-3 and thyroid hormones
• Statistical analysis
– Multiple regression model
– Covariates : age, sex, race and ethnicity, BMI, urinary cotinine, iodine, and creatinine
56
ln-Free T3 ln-Free T4 ln-TSH
β (95% CI) p-
value
β (95% CI) p-
value
β (95% CI) p-
value
-0.0011
(-0.0036 to 0.0013)
0.37 -0.0044
(-0.0083 to -0.00053)
0.026 0.014
(-0.0010 to 0.030)
0.067
Total T3 Total T4 ln-Tg
β (95% CI) p-
value
β (95% CI) p-
value
β (95% CI) p-
value
-0.36872
(-0.89 to 0.16)
0.17 -0.070
(-0.11 to -0.033)
0.0002 0.00022
(-0.024 to 0.024)
0.99
ln-BP-3*ln-Free T3 ln-BP-3*ln-Free T4 ln-BP-3*ln-TSH
NHANES 2007-2008
Our cohort
• Children’s Health and Environmental Chemicals in Korea Cohort
• to construct an exposure profile for newborns and their mothers through time. • to assess the adverse effects on birth outcome and onward Participants
57
• 352 pairs of pregnant women and fetuses
• Seoul, Anyang, Ansan, and Jeju (2011-2013)
– Study team
• ~20 professors from 3 universities and 6 university hospitals
Phthalates and thyroid hormone levels in CHECK panel mothers
• Individual model – adjusted for maternal age, BMI, gestational
age, delivery mode, parity
58
Thyroid hormone
Phthalates β p
Free T3 MEHP -0.033
Phthalates and thyroid
• Cross-sectional study
59
In children who had phthalate-tainted food, TSH were inversely associated with intake amount (Wu et al. 2013)
MEHP, MEP, and MBP was negatively associated with total T3 and free T3 in children (Boas et al. 2010)
Total T3 and free T4 were negatively associated with DEHP metabolites, but no relationships with TSH, total T4 and free T3 (Meeker et al. 2007)
• Possible mechanism in Zebrafish study
- Dio (Deiodinases) gene induction - UGT (conjugation and excretion) induction
(Zhai et al., 2014)
(MEHP exposure)
POPs and thyroid hormones
60
Matrix n POPs Thyroid hormone measurement Reference fT3 TT3 fT4 TT4 TSH matrix
Cord serum 104 PCBs - ↑ - - - / ↓s Cord serum & bloodspot
This study
PBDEs - - - - ↑ / ↑s OCPs - ↓ - ↓ - / ↑s Cord serum 108 PBDEs - - Cord serum Kim et al. (2009b) Cord serum 297 PBDEs - ↓ / -s - Cord serum &
bloodspot
Herbstman et al. (2008b)
PCBs ↓ / -s - / ↓s -
Cord serum 39 DDTs - ↓ - Cord serum Asawasinsopon et al. (2006) Cord serum 92 PCBs - - - Cord blood Takser et al. (2005)
Cord serum 70 HCB, PCBs, p,p’-DDE
-s bloodspot
Ribas-Fito et al. (2003)
β-HCH ↑ Cord plasma 410, 260 PCBs - - - Cord serum
Dallaire et al. (2008) HCB - ↑ - Cord plasma 198 PCBs, HCB ↓ ↓ -
Cord plasma Maervoet et al. (2007)
p,p’-DDE ↓ - Cord blood 90 PBDEs - - ↓ - - Cord blood Kim et al. (2011) Cord blood 50 PCBs - ↓ -
Cord blood Zhang et al. (2010)
PBDEs - - - Cord blood 54 PBDEs ↓ ↓ - - - Cord blood Lin et al. (2010) Maternal serum
104 PCBs - - - - - / -s Cord serum & bloodspot This study PBDEs - - - - - / ↑s
OCPs ↓ ↓ ↓ - - / ↑s (Kim et al., 2015)
Possible topics for study
• Identifying important chemicals of concern – Sensitive human populations: Pregnant women or
young children
– Susceptible population: E-waste workers
• Associating health effects – Hormones, birth outcomes, diseases
• Tracing exposure sources
Promising topics of study: Alternatives
• Bisphenol A vs S
• PBDEs vs TDCPP
• DEHP vs DEHT
ขอบคุณ
Acknowledgement ETL, SPH, SNU (SM Kim, SW Lee, SJ Kim, JE Jung, H-B Kang) CHECK Study Team (Prof SK Kim, H-B Moon, J Park) CHECK participants KFDA, NRF
Department of Environmental Health Sciences and Collaborations
Environmental Monitoring
Environ Hlth Microbiology
Biomonitoring
Environ Chem & Monitoring
Air Pollution & Climate Change
Occup Hygiene
Exposure Sci Indoor Environ Qual
Environ/Occup Medicine
Environ Hlth Engineering
Environ Toxicology
Environmental Monitoring
• Fate and transport of chemicals
– Hg, pharmaceuticals and personal care products, perfluorinated compounds, etc
• Exposure modelling of pollutants in air and water
Exposure assessment/Biomonitoring
Environ Hlth Microbiology
Biomonitoring
Environ Chem & Monitoring
Air Pollution & Climate Change
Occup Hygiene
Exposure Sci Indoor Environ Qual
Environ/Occup Medicine
Environ Hlth Engineering
Environ Toxicology
Exposure assessment
• Exposure assessment in indoor
– PM2.5, SHS, VOC, nano, HAPs
– dust mite, bioaerosol in home
• Workplace exposure assessment
– welding fume, nano, asbestos, EDCs, PBDEs
• Exposure assessment in humans
– BDEs, PCBs, POPs/EDCs
Biomonitoring
• Designing National Environmental Health Biomonitoring Program
• Biomarkers of exposure and effect
• Construction and validation of PBPK and reverse dosimetry
Toxicology and risk assessment
Environ Hlth Microbiology
Biomonitoring
Environ Chem & Monitoring
Air Pollution & Climate Change
Occup Hygiene
Exposure Sci Indoor Environ Qual
Environ/Occup Medicine
Environ Hlth Engineering
Environ Toxicology
Toxicology and risk assessment
• Environmental toxicology of POPs, EDCs, pharmaceuticals
– Endocrine disruption potentials of EDC alternative chemicals
• Exposure and risk assessment of chemicals among susceptible humans
– Risks of phthalate exposure through breastfeeding
Microbiology and health effects
Environ Hlth Microbiology
Biomonitoring
Environ Chem & Monitoring
Air Pollution & Climate Change
Occup Hygiene
Exposure Sci Indoor Environ Qual
Environ/Occup Medicine
Environ Hlth Engineering
Environ Toxicology
Microbiology and health effects
• Microbiome in twins and health implications
• Norovirus and public health
• Exposure assessment of dust mite, bioaerosol in home
Health effect and epidemiology
Environ Hlth Microbiology
Biomonitoring
Environ Chem & Monitoring
Air Pollution & Climate Change
Occup Hygiene
Exposure Sci Indoor Environ Qual
Environ/Occup Medicine
Environ Hlth Engineering
Environ Toxicology
Health effects and epidemiology
• Health effect assessment
– Community Health Survey Near Industrial Complex Study on Reproductive Health Problems among Hospital Workers
– Health Risk Assessment on Semiconductor (Fab) Workers
– Laboratory health issues
• Cohort studies
– EDCs and health effects among mother-baby pairs
Hormones Hormones are molecules produced by
specialized cells in a large variety of glands and tissues
These molecules travel through the blood to produce effects at sometimes distant target tissues
송과선
부갑상선
시상하부
뇌하수체
갑상선
흉선
부신
생식선
Experimental measures
• Thyroid hormone disruption In vitro In vivo
Thyroid gland FRTL5 (Rat)
Thyroid hormone Synthesis/Regulation
Pituitary gland GH3 (Rat)
Central regulation
(hpf, hours post-fertilization)
0 hpf embryo 120 hpf larva 48-72 hpf 1
Development - Hatchability - Malformation rate - Larval survival
Sampling
T3, T4 Gene transcription
Early life stage of zebrafish
Thyroid hormones (THs)
• Functions – Increase basal metabolic rate – Essential to proper development and
differentiation of all cells – Regulate protein, fat, and carbohydrate
metabolism
– Changes of THs even within normal range may cause significant effects on development of cognitive function of fetus (Berbel et al., 2009; Haddow et al., 1999; Pop et al., 2003; Porterfield, 1994)
• Regulated by TSH secreted from
pituitary gland Thyroid hormones: Triiodothyronine (T3) and its prohormone, thyroxine (T4)
wikipedia
2015-08-24 79
– Growing body of evidence on chemicals and thyroid toxicity, but still limited direct evidence in human populations (WHO/UNEP, 2012)
(Laurberg, 2009)
Chemicals on thyroid hormone homeostasis
Materials and methods
2015-08-24 80
• Subjects and sampling – IRB of SPH SNU – 105 pregnant women participating CHECK Panel study – Questionnaire and blood sampling just before delivery
• Target POPs with > 60% detection – OCPs 19: dichlorodiphenyl trichloroethanes (DDTs), chlordanes (CHDs), hexachlorocyclohexanes (HCHs),
hexachlorobenzene (HCB), heptachlor, heptachlor epoxide, mirex – PCBs 19: PCB18, 28, 33, 44, 52, 70, 101, 105, 118, 128, 138, 153, 170, 180, 187, 194, 195, 199 and 206 – PBDEs 19: BDE17, 28, 47, 49, 66, 71, 77, 85, 99, 100, 119, 126, 138, 153, 154, 156, 183, 184 and 191
• Thyroid related hormones – tT3, fT3, tT4, fT4, TSH
Seoul
Ansan
Anyang
Jeju
Materials and methods
• Subjects and sampling – Pregnant women and matching fetuses pair participating in CHECK Panel (n=104) – Questionnaire, blood sample collection from mother before delivery and from cord during
delivery
• Thyroid hormones
– tT3, fT3, tT4, fT4, TSH from mother and her infant – TSH in bloodspot at day 2-3 after birth
• Target POPs with > 60% detection
– Use of proxy values with the same method as that for maternal blood measurement
• Statistical analysis
– Natural regression model – Covariates: maternal age, prepregnancy BMI,
gestation, number of pregnancy, mode of delivery
• Maternal thyroid hormone levels were also added in the regression model
2015-08-24 81
Interaction between thyroid hormones and sex hormones
• Regulation of hormone dynamics
– Hypothalamic-pituitary-thyroid (HPT) axes : thyroid system
– Hypothalamic-pituitary-gonad (HPG) axes : reproductive system
– Hypothalamic-pituitary-adrenal (HPA) axes : adrenal system
82
● T ○ E2
○ T4 ● T3
Reported interaction between thyroid and sex hormone in fish
• THs may inhibit the production or secretion of sex hormones – T4 treatment in female catfish decreased both tissue or serum E2 level (Supriya et al.,
2005)
– In female zebrafish, concentrations of FSH and LH were negatively correlated with concentrations of T4 and T3 (Liu et al., 2011)
• THs also seem to directly act on fish oocytes – T4 treatment in female catfish increased vitellogenic/post-vitellogenic follicles,
suggesting rapid oocyte growth (Supriya et al., 2005) – T3 administered along with gonadotrophin (GTH) increased E2 production in
ovarian follicles isolated from adult Japanese medaka (Soyano et al. 1993)
• THs play an important role in testicular development and function (Wagner et al.,
2008)
83
• E2 can suppress T3 production in fish
– E2 treatment reduced plasma T3 levels in immature rainbow trout (Letherland, 1985; Mercure et al., 2001) and in salmon (Yamada et al., 1993)
– In female fish when plasma E2 levels are high, thyroid hormones tend to be low (Cyr et al., 1988; Norberg et al., 1989)
Sex hormone and thyroid hormone changes by TDCPP or
TPP • In adult male and female zebrafish
84
Related underlying mechanisms
• Cross-talk : central hormone regulation 변화 – E2 decrease by prochloraz (PCZ) down-regulated the CRH gene expression and T4 decreased by
PTU up-regulated the FSH and LH gene expression in adult female zebrafish (Liu et al., 2011)
• E2 증가에 의한 deiodination activity 변화 – E2 decreased T4-ORD activity and rT3-ORD activity in liver, but increased kidney T3-IRD activity
in both sexes (Wiens and Eales, 2005) ; hepatic T3 감소 또는 renal T3 degradation 증가
• 갑상선 호르몬 변화와 steroidogenesis 간의 연관성 – PTU, an antithyroid medicine, decreased T4 cyp11a and star gene expression and production of
testosterone in rat leydig cells (Chiao et al., 2002)
85
PCZ exposure PTU exposure
Atrazine disrupts sex of frogs
• An atrazine-induced female frog (a genetic male) is shown (bottom) copulating with an unexposed male sibling. This union produced viable eggs and larvae that survived to metamorphosis and adulthood. Yet, because both animals were genetic males, the offspring were all males. (Tyrone Hayes photo)
PNAS 2010 107, 4613
Japanese medaka (Oryzias latipes)
• A suitable model for evaluating the estrogenicity of EDCs and reproductive effects
• Recommended for testing of chemicals - OECD TG 203 (Fish, Acute Toxicity Test)
- OECD TG 204 (Fish, Prolonged Toxicity Test: 14-day Study)
- OECD TG 210 (Fish, Early-life Stage Toxicity Test)
- easy to control the spawning
- good to obtain a number of eggs
Regulating thyroid hormone balances
Human observations- POPs and thyroid hormones in serum
(Kim et al., 2013)
Human observations- POPs and thyroid hormones in serum
2015-08-24 90
Matrix n POPs Thyroid hormone measurement Reference fT3 TT3 fT4 TT4 TSH matrix
Cord serum 108 PBDEs - - Cord serum Kim et al. (2009b) Cord serum 297 PBDEs - ↓ / -s - Cord serum &
bloodspot
Herbstman et al. (2008b)
PCBs ↓ / -s - / ↓s -
Cord serum 39 DDTs - ↓ - Cord serum Asawasinsopon et al. (2006)
Cord serum 92 PCBs - - - Cord blood Takser et al. (2005)
Cord serum 70 HCB, PCBs, p,p’-DDE
-s bloodspot
Ribas-Fito et al. (2003)
β-HCH ↑ Cord plasma
410, 260
PCBs - - - Cord serum Dallaire et al. (2008)
HCB - ↑ - Cord plasma
198 PCBs, HCB ↓ ↓ - Cord plasma
Maervoet et al. (2007)
p,p’-DDE ↓ - Cord blood 90 PBDEs - - ↓ - - Cord blood Kim et al. (2011) Cord blood 50 PCBs - ↓ -
Cord blood Zhang et al. (2010)
PBDEs - - - Cord blood 54 PBDEs ↓ ↓ - - - Cord blood Lin et al. (2010)
(Kim et al., 2015)
Questions
• EDCs and thyroid hormones among sensitive human
populations
– Pregnant women and newborn infants
• Experimental approach to screen thyroid disruption of
substituting chemicals
– Flame retardants- TPP, Firemaster, Dechlorane Plus
91
Study population
• Children’s Health and Environmental Chemicals in Korea Panal
• to construct an exposure profile for newborns and their mothers through time.
• to assess the adverse effects on birth outcome and onward
– Participants
2015-08-24 92
• 352 pairs of pregnant women and fetuses
• Seoul, Anyang, Ansan, and Jeju (2011-2013)
– Study team
• ~20 professors from 3 universities and 6 university hospitals
Association between several persistent organic pollutants and thyroid hormone
levels in serum among the pregnant women of Korea
(Kim SM et al., Environ Int 2013)
POPs
versus
T3, T4, TSH
Maternal Blood
Materials and methods
• Statistical analysis
– Use of proxy values for nondetects
• LOQ ( limit of quantification) / √2 for chemicals >75% detection
• Only detected values were used for statistical analysis for chemicals 60-75% detection
– Effects of maternal blood serum POPs on thyroid hormones
• Multiple linear regression
• Natural log transform measured POPs data
• Covariates: maternal age, pre-pregnancy BMI, gestation period, number of pregnancies, mode of delivery
2015-08-24 94
Association between POPs and THs in maternal serum
2015-08-24 95
Free T3 Total T3 Free T4 Total T4 TSH
β 95% CI β 95% CI β 95% CI β 95% CI β 95% CI
PCB
ΣPCB -0.053^ -0.108, 0.002 -0.117* -0.198, -0.036 -0.029 -0.084, 0.027 -0.056* -0.109, -0.002
0.195 -0.167, 0.556
PCB28+ -0.015 -0.057, 0.027 -0.025 -0.100, 0.050 -0.068* -0.117, -0.019 -0.030 -0.081, 0.020 0.172 -0.165, 0.510
PCB52+ -0.092* -0.159, -0.026
-0.113* -0.223, -0.003 -0.011 -0.067, 0.044 -0.023 -0.081, 0.035 0.192 -0.146, 0.530
PCB118+ -0.020 -0.091, 0.051 -0.114* -0.223, -0.005 -0.049 -0.136, 0.038 -0.047 -0.134, 0.040 0.389 -0.183, 0.960
PBDE
ΣPBDE -0.049* -0.088, -0.009
-0.112* -0.170, -0.054 0.058* 0.016, 0.100 0.007 -0.032, 0.046 -0.055 -0.318, 0.209
BDE47 -0.021 -0.049, 0.007 -0.042* -0.084, -0.000 0.028 -0.001, 0.057 0.006 -0.021, 0.033 0.024 -0.154, 0.203
OCP
tNCHD -0.033 -0.095, 0.029 -0.085 -0.188, 0.018 -0.049 -0.118, 0.021 -0.059^ -0.128, 0.010 0.225 -0.160, 0.609
ΣDDT -0.052^ -0.104, 0.000 -0.096* -0.179, -0.013 -0.045 -0.106, 0.016 -0.035 -0.093, 0.022 0.299 -0.072, 0.670
p,p’-DDT 0.002 -0.035, 0.039 0.004 -0.053, 0.061 -0.045* -0.083, -0.008 -0.015 -0.051, 0.021 0.145 -0.090, 0.380
HCB+ -0.012 -0.061, 0.037 -0.035 -0.108, 0.038 -0.047* -0.095, -0.000 -0.023 -0.071, 0.026 0.091 -0.183, 0.365 Signs * and ^ indicate statistical significance at p=0.05, and 0.1, respectively. All POPs concentrations are in ng/g lipid and were natural log –transformed. Results of association were adjusted for age, gestation period, mode of delivery, parity, and pre-pregnancy BMI. Chemicals that were detected >=75% of the population at concentrations greater than the limit of quantification, a proxy value of ‘limit of quantification divided by square root 2’ was used. For chemicals that were detected in =60%, statistical analysis was conducted with detected values only. Such chemicals are indicated by ‘+’.
(n=105)
Significant association with TH remains for PCBs
2015-08-24 96
• Are effects of PBDEs real? – Significance correlation in
Spearman analysis
• between PCB52 and BDE47, and
• among BDE47, PCB52, and PCB118
– When all were entered in the model, only the effect of PCB52 remains
• DDTs, HCB, CHDs were generally associated with decrease of T3 or T4
Variables free T3
β 95% CI
BDE47 -0.039^ -0.081, 0.003
PCB52 -0.072* -0.141. -0.004
total T3
β 95% CI
BDE47 -0.006 -0.076, 0.063
PCB52 -0.114 -0.305, 0.076
PCB118 -0.078 -0.259, 0.104
Adjusted associations with significant PCBs as covariates between serum PBDEs and free or total T3 in pregnant women
Significant results from multiple regression analysis using each individual congener (Table 3) were reanalyzed by adding PCB52 for testing relationship between BDE47 and free T3, and PCB52 and 118 in model for testing relationship between BDE47 and total T3 as covariates.
Association between POPs exposure and thyroid hormones among newborn infants
(Kim SM et al., PlosOne 2015)
POPs
versus
T3, T4, TSH
Cord Blood
Challenges in studying thyroid hormones in newborns
• Cord thyroid hormones fluctuate significantly
2015-08-24 98
– Especially around delivery due to many causes (Herbstman et al., 2008)
– On average 30-60% of cord blood serum T4 is from mother (Thorpe-Beeston et al., 1991; Vulsma et al., 1989)
Vein (to baby)
Artery (to mother)
• Not feasible to sample blood from newborns • Bloodspot collected at days 2 and 18 after birth to measure T4
(Herbstman et al. 2008)
• May better reflect stable thyroid hormone levels of newborn
-> Measure thyroid hormones in bloodspot of newborn
-> Correct cord blood serum data with maternal serum TH levels
Association between POPs and THs in newborn infant serum
2015-08-24 99
Signs * and ^ indicate statistical significance of regression parameter at p=0.05, and 0.1, respectively. # indicates no significance of model in F test (p for ANOVA). For chemicals that were detected in =60%, statistical analysis was conducted with detected values only. Such chemicals are indicated by ‘+’.
Cord serum POPs (ng/g lipid)
Cord blood Bloodspot
Free T3 (pg/mL) Total T3 (ng/mL) Free T4 (ng/dL) Total T4 (μg/dL) TSH (μlU/mL) TSH (μlU/mL)
β 95% CI β 95% CI β 95% CI β 95% CI β 95% CI β 95% CI
PCB ΣPCB 0.012 (-0.03, 0.05) 0.034^ (0.00, 0.07) -0.002 (-0.02, 0.02) 0.004 (-0.03, 0.04) 0.012 (-0.10, 0.13) -0.160^ (-0.33, 0.01)
PBDE BDE-47+ -0.016 (-0.09, 0.06) -0.017 (-0.09, 0.06) -0.015 (-0.06, 0.03) -0.002 (-0.07, 0.06) 0.077 (-0.15, 0.31) 0.327* (0.03, 0.62)
BDE-99+ 0.008 (-0.06, 0.07) 0.013 (-0.05, 0.08) 0.002 (-0.04, 0.04) 0.013 (-0.05, 0.07) 0.210* (0.00, 0.42) 0.037 (-0.24, 0.32)
OCP β-HCH+ -0.023 (-0.11, 0.06) -0.002 (-0.09, 0.08) -0.019 (-0.07, 0.03) -0.016 (-0.10, 0.07) 0.106 (-0.16, 0.37) -0.270^ (-0.57, 0.03)
ΣCHD 0.018 (-0.04, 0.07) 0.029 (-0.02, 0.08) 0.005 (-0.02, 0.03) 0.021 (-0.03, 0.07) 0.149^ (0.00, 0.30) 0.197 (-0.05, 0.45)
p,p’-DDE -0.033 (-0.07, 0.01) -0.038^ (-0.08, 0.00) -0.002 (-0.02, 0.02) -0.016 (-0.05, 0.02) 0.082 (-0.04, 0.21) 0.208* (0.03, 0.39)
HCB+ -0.019 (-0.05, 0.01) -0.016 (-0.05, 0.02) -0.004 (-0.02, 0.01) -0.029* (-0.06, 0.00) 0.059 (-0.04, 0.16) -0.109 (-0.28, 0.06)
Maternal serum POPs (ng/g lipid)
Free T3 (pg/mL) Total T3 (ng/mL) Free T4 (ng/dL) Total T4 (μg/dL) TSH (μlU/mL) TSH (μlU/mL)
β 95% CI β 95% CI β 95% CI β 95% CI β 95% CI
β 95% CI
PBDE BDE-47 -0.006 (-0.04, 0.03) -0.010 (-0.04, 0.02) 0.004 (-0.01, 0.02) -0.008 (-0.03, 0.02) -0.028 (-0.13, 0.07) 0.130^ (-0.04, 0.29)
OCP β-HCH -
0.044* (-0.08, -0.01)
-
0.039* (-0.08, 0.00) -0.017 (-0.04, 0.00) -0.028 (-0.06, 0.01) 0.066 (-0.06, 0.19)
0.041 (-0.12, 0.26)
ΣCHD
-0.005 (-0.08, 0.07) -0.013 (-0.08, 0.05) -
0.038* (-0.08, -0.01)
-
0.056^ (-0.12, 0.00) 0.009 (-0.21, 0.23)
-0.221 (-0.41, 0.16)
ΣDDT -0.027 (-0.10, 0.05) -0.023 (-0.10, 0.05) -0.017 (-0.06, 0.02) 0.004 (-0.06, 0.07) -0.013 (-0.25, 0.22) 0.345* (0.06, 0.81)
p,p’-DDE -
0.036^ (-0.08, 0.01) -0.028 (-0.07, 0.01)
-
0.020^ (-0.04, 0.00)
-
0.034^ (-0.07, 0.01) 0.001 (-0.13, 0.13)
0.264* (0.11, 0.50)
HCB -0.005 (-0.04, 0.03) -0.015 (-0.05, 0.02) 0.001 (-0.02, 0.02) -0.011 (-0.04, 0.02) 0.089^ (-0.02, 0.19) -0.095 (-0.26, 0.09)
30% ↑ per BDE47 IQR ↑
5, 4% ↓ per β-HCH IQR ↑
25, 19% ↑ per DDT and p,p’-DDE IQR ↑
17% ↑ per p,p’-DDE IQR ↑
With all chemicals with strong correlation with each other, effects of PBDEs and OCPs remain
significant in the model
2015-08-24 100
Cord POPs Cord or bloodspot Thyroid hormones
β (95% CI) n
ΣPCB TT3 0.02 (-0.02, 0.06) 89
p,p’-DDE TT3 -0.04^ (-0.09, 0.00)
BDE-99 Cord TSH 0.22* (0.00, 0.42) 57
ΣCHD Cord TSH 0.13 (-0.06, 0.33)
ΣPCB bloodspot TSH 0.07 (-0.13, 0.27) 64
BDE-47 bloodspot TSH 0.38* (0.08, 0.67)
ΣCHD bloodspot TSH 0.04 (-0.20, 0.28) 72
p,p’-DDE bloodspot TSH 0.54* (0.25, 0.82)
Maternal POPs Cord or bloodspot Thyroid hormones
β (95% CI) n
β-HCH fT3 -0.04^ (-0.08, 0.01) 94
p,p’-DDE fT3 -0.02 (-0.07, 0.03)
ΣCHD fT4 -0.03 (-0.07, 0.01) 87
p,p’-DDE fT4 -0.01 (-0.05, 0.02)
BDE-47 bloodspot TSH 0.02 (-0.13, 0.18)
88 ΣDDT bloodspot TSH -0.13 (-0.58, 0.32)
p,p’-DDE bloodspot TSH 0.45* (0.14, 0.76)
Newborn infants
• POPs associated with thyroid hormones – BDE47, BDE99, p,p’-DDE, ΣDDT, β-HCH,
ΣCHD, HCB
• More reliable measurement of association – Adjusting cord blood serum hormones with
those of mother’s
– Employing bloodspot TSH measurements
2015-08-24 101
BP-3 and thyroid hormones
• 1,852 subjects in NHANES 2007-2008
– 971 males and 881 females
– Ages from 12 to 80 yrs
• Urinary environmental phenol conc. (ng/mL)
– 4-tert-octyl phenol, BP-3, BPA, TCS
– Parabens (MP, EP, PP, and BP)
• Serum thyroid measures
– TSH (μIU/mL)
– Free T3 (pg/mL) and T4 (ng/dL)
– Total T3 (ng/dL) and T4 (μg/dL)
– TPO antibody (IU/mL)
102 NHANES 2007-2008