DIOXINS

DIOXINS
Pollution,, public
p
health and risk management:
g
examples from dioxins historical events
Hervé BOILEAU
Associate professor in process engineering
Polytech Annecy Chambéry
Faculty of Engineering, University of Savoie, France
DIOXINS
• Dioxins, not dioxin : a family of molecules
– organics,
i
polycyclics,halogenated
l
li h l
t d:
two phenol cores
two oxigen bridges
hydrogen substituted by chlorine
Complete name : polychlorodibenzo-para-dioxins
PCDD
PCD Furans
1
The most dangerous :
2 3,
2,
3 7,
7 8 TCDD
Why : the more symetric
Symetry = stability = accumulation = danger
Short History
• 1872 :
ortochlorodioxin
Merz & Weith
• 1957 :
tetrabromodioxin
Gilman & Dietrich
• tetrachlorodioxin
Sandermann
2
Ways of toxicity
* High lipophilicity
* Bioaccumulation in the food chain
Health consequences
• Skin manifestations :
• Neurological effects :
– sexual dysfunction,
– chloracne, hyperkeratosis,
headache, neuropathy, loss
hyperpigmentation, hirsutism
of hearing taste and smell,
• Systemic effects :
sight disturbance
– hypercholesterolemia,
h pertrigl ceridemia loss of• Psychiatric effects :
hypertriglyceridemia,
– sleep disturbance,
appetite, weight loss,
depression, loss of energy,
digestive disorders,
anxiety, apathy, emotional
cardiovascular, urinary,
instability, anorexia,
respiratory and pancreatic
learning disability...
disorders...
Health consequences
• The most famous victim of chloracne due to dioxins is the
P id t off Uk
President
Ukraine
i Vikt
Viktor IOUCHTCHENKO.
IOUCHTCHENKO
• See below,
– Before and after
being poisoned
by the FSB
– 1 g has been
estimated in
his body
3
Tolerable daily Intake
• W.H.O.: 10 pg/d/kgBW
• Europe: 1 pg/d/kg BW
-6
• USA: 10 during 70 years
6.4 fg/d/kgBW
Pico : 10 –12 Femto : 10 -15
Tolerable daily Intake;
any significance ?
• In fact NO,, because there is no threshold
effect: even ONE molecule of dioxin may
have consequences on the expression of a
gene.
• The only limit based on physical effects is
th U
the
Us'' one: 160 tto 1600 times
ti
lless th
than
EU levels
4
24 D and 245 T herbicides
• First agricultural use : 1941
• 1950 : 16 000 T used
• 1960 : 60 000 T used
• 20 times more toxic than sodium cyanide
• But 30 000 less than botulism toxin
Spraying herbicides...
Remember Carry
y GRANT
pursued by a spraying biplane,
in the Alfred HITCHKOCK ’s
thriller
North by Northwest
5
Vietnam war and the Agent
Orange controversy
6
Use of herbicides
• Fall 1961: first tests of 18 mixtures
• 9 January 1962: first shipment of agent Purple
• agent Orange appears in 1965
Agent orange ?
7
Herbicides sprayed over
Vietnam :
• April ’70
70 : Pres.
Pres NIXON asks to stop using
Agent Orange, because of the toxicity of the
dioxins included
– US Army has massive stocks :
d id tto d
decides
destroy
t
th
them…
8
Agent Orange controversy still alive
30 years later
In France, Talc Morhange scandal
• March 1972 : use of hexachlorophene
as bactericide in talc : efficient against
gram + bacteria and fungi
• 36 death
• 145 birth defect
9
Talc Morhange Scandal
• Responsability of the talc demonstrated
– 600 kilograms of talc infected
– 3 000 boxes with 6.35 % of hexachlorophene
• The company DELIBERATELY hid the toxic
potential
– This scandal led to a hug e change in the
g
from
legislation
a negative to a positive list of products
(from prohibited to authorized)
Toxicity of hexachlorophene
• US DHS and NIEH :
– groups of 24 rats, dose from 17, 50 to 150 ppm,
105 weeks
– no tumours in a “statistically significant evidence”
– higher dose : 200 to 600 ppm neural necrosis
– In the conditions of the bioassay :
"no level of evidence of carcinogenicity"
10
Talc Morhange Scandal
• The company was prosecuted…
prosecuted
• amnestied in '80
• '88 : survey of 56 contaminated children :
– "low educational ability was demonstrated"
SEVESO
11
Before SEVESO,
many other
industrial
accidents
SEVESO
• Friday 9 July 1976, 4 pm, reactor filled in
• Saturday,
S t d
5 am : stirring
ti i d
device
i stops
t
• 12 h 30 : rupture disk burst, a part of the reactor
content spread out over the surroundings.
12
SEVESO
• July 26
26, 557 people
evacuated from zone A
• All animals killed in zone
A, B & R
• 600 p
persons with skin
lesions, but only 34 from
chloracne
• Results of
the survey
Conclusion of the International Steering Committee ( Feb. ’84)
"nearly eight years after the accident in Seveso
it has become obvious that besides chloracne
in a very small group of cases, no adverse health effects
related to the chemical produced by the accident have been
observed".
13
Other sources of dioxins
• incinerators ? Now, in western countries all
incinerators are monitored, results published
on the net.
• Industries
PCBs
14
What are PCBs ?
• Polychlorinated
y
biphenyls, close to
PCDD and PCDF
– 209 different forms
– Commercial names :
• Askarel
Askarel, Chlophene
Chlophene,
Arochlor, Pyralène
Characteristics of PCBs
•
•
•
•
•
•
•
Consistency : from light oil to wax
colourless or yellow, characteristic smell
insoluble in water, slightly soluble in organic
remarkable thermal stability
highly chemically inert to acids and bases
no reaction with common metals
high dielectric strength
15
Use of PCBs
• Because of their properties PCBs have
b
been
used
d ffor :
– mastics, paints, varnishes, adhesives, inks,
lubricants…and chewing gum !
– Dielectric fluids (capacitors and transformers),
heat transfer fluids, hydraulic fluids...
• Wide use : capacitors and transformers
– before '76 : any may contain
– from '76 to '86 : may be present
• Consequences and risks ?
16
Health consequences
• Knowledge
g on consequences
q
comes from
survey on workers
– long term exposure : harmful effects to the skin as
chloracne…damages to eyes (irritation, redness…)
• higher doses have been studied on animal
survey :
– large exposure on skin causes death, smaller
amounts causes liver, stomach and thyroid glands
injuries
Health recommendations
• '91 : US DHHS
• "PCBs may reasonably be anticipated to be carcinogens,
but studies on workers do not provide enough
information"
• US EPA
-3
– 10 ppb in lakes and rivers
– drinking water : 4 mg/L for adults, 1 for kids
• US FDA
– 0,2 ppb in food
17
Health recommendations
• US NIOSH
-3
3
– workers should breathe air < 10 mg/M
• US OSHA
3
– workplace exposure limit 0.5 mg/M for 8 hours
Second aspect of public
health related with PCBs
18
PCBs burning
• After Seveso,
Seveso awareness of people
• when PCBs burn, they produce dioxins and
furans or polychlorodiphenylene (PCDP)
• All transformers have to be destroyed in
specific
spec
c furnaces
u aces
PCBs transformers destruction
Specialists in France : TREDI, near Lyon,
a company specialised in hazard waste destruction
19
General scheme of the
treatment plant
Belgian chicken scandal
20
“Dioxin's chicken”
• 15th Januaryy '99 : an egg
gg p
producer asks
his insurance company to elucidate the
decrease of egg production in his plant
• 24th of March : the guilty company is
identified.
– Mix together oils from restaurants, frying
fat…but also industrial oils from engines
and transformers
– mix sold to animal flour producers
Consequences ?
• A huge scandal
• and two ministers led to
resignation...
21
Waste incineration and PCDD
• Incinerators are known to produce dioxins
dioxins…as
as
iron and steel factories or wood burning !
• Last scandal in France…close to Chambéry
Waste incineration
• Anthropogenic source of TCDD :
– proven in '77 by OLIE, VERMEULEN &
HUTZINGER
– Mechanism : in '85, SHAUB & TSANG proposed
an heterogeneous fly ash catalysed reaction
• fl
flue gas + ash
h + ttemperature
t
< 900°C
• The reaction occurs in the post combustion chamber
22
Waste Incineration
RTD : 1 to 3 hours for solid waste,
Some seconds for generated gas
So, post combustion chamber
is needed to "achieve" the
combustion
Waste incineration
• Strange consequence :
– gas treatment and particularly ash
collection on electrostatic precipitators
INCREASE the production of dioxins !
• Flue gas cooled
• long residence time of ashes
23
Waste Incineration
Heat exchanger
g =g
gas cooling
g
Fly ash collection
by electro
precipitators
=
higher ash
residence time
Waste incineration
Two main mechanisms
–carbon : reduction in CO2
• 1 % reduced into chlorinated benzene core
• 0.01 to 0.04 % into PCDD or PCDF
–Small
Small organic Molecules
• Many different mechanisms :
–Propene (C3H6) to PCDF ??
–Chlorophenol condensed into PCDD...
24
Dioxins reduction from incinerators
• Ban PVC
– in France we were used to
pack water in PVC bottles
– Now, PVC is avoided,
water is packed in PET
– …and beer too !
Dioxins reduction from
incinerators
• But 0% of chlorine source is an
unreachable target, there still remain
some sources :
– PVC from building waste (pipes, windows,
gutter, drainpipes…)
– solvents in households
– Organics containing chlorine…
25
Dioxins reduction from
incinerators
• Technological
g
way
y:
– high temperature ash recovery
• Pb: filters material
– THEN, flue gas cooling
– or a second burning of
with flue gas
treatment
gas
chemical
Dioxins reduction from
incinerators
• More developed now:
– Chemical and
adsorption
• Li
Lime and
d active
ti carbon
b iin
fluidized bed
26
Dioxins reduction from incinerators
• Or adsorption on
supported AC
– Ex : ADIOX from
Götaverken Miljö
company
2378 TCCD
molecules
adsorbed
on AC
27
Dioxins reduction from
incinerators
• Mass transfer problems :
– always the same :
a surface problem
• Increasing contact
surface while reducing
volume, and keep void
for gas expansion…
Dioxins reduction
from incinerators
28
Dioxins reduction
from incinerators
Dioxins reduction from
incinerators
29
Dioxin episode near Chambéry
• Household waste incinerator of Gilly
– 50 km from Chambéry, in the valley of
Albertville
• Capacity : 27 000 T/y, 50 villages or small towns
collected, 64 000 inhabitants concerned
• October 2001 : red alert for milk and dairy
produce :
– dioxin concentration is over the 5 picograms per
gram of fatty content authorised
Dioxin episode near Chambéry
• An inquiry is ordered :
– flue gas sometimes exceed 700 times the
European authorised level !
– European record of the most contaminated cow :
70 picograms/gram of fatty content
• Consequences :
– of course, incinerator immediately closed
– huge worry of the concerned population
30
Farmers and dairy producers are worried
The lack of information is denounced
31
People are worried
Consequences
• 246 farms affected, 2 500 cows, sheep,
ewes goats
ewes,
goats…killed
killed
• 16 000 litres of milk a day to be destroyed
• hundreds of tons of hay to be buried
• …and a huge psychosis :
– one citizen noticed in the same village 72 cancer
events…amongst these, 25 in the same street !!
• Of course, it's a small village, 2 or 3 streets at all…and
no proof of the origins of these cancers
32
What's going on in Europe?
• Legal point of view :
– EU directive 94/67/EG
• Max level in exhaust gas : 0.1 ng I-TEQ/m3
– Translated into French laws
• For incinerators : difference upon scale :
– Under and over 6 T/h
• Exhaust Dioxine in g/y, • Exhaust Dioxine in g/y,
municipal waste
municipal waste
incinerators UNDER 6 T/h incinerators OVER 6 T/h
9
/2.5
9
/6 : scale effect
33
• Classical conclusion :
– small plants should be closed down:
– because of the high cost of treatment and
survey, large plants should be developped…
– But this lead to another episode of NIMBY
syndroma, linked to a large "dangerous" plant !
• Then larger plants also put on the
question of the Carbon print:
– The bigger it is, the more you treat waste;
– In low density regions, the longer the
distance is to bring waste, the more you
consume fuels to transport such waste, thus
you degrade the incinerator’s carbon print
34
Second question :
• At this so low level (0,1 ng/Nm3, collected
d i 6 or 8 h) iis th
during
there any reliable
li bl
sampling technology ?
• 0,1 ng/Nm3=10-18, can we be sure that the
sampling network is at least 100x cleaner
cleaner,
10-20 …
• Classical incinerator in France ; At least 2 furnaces,
6T/h, 8000 h/Y = 100 000 T/y
This incinerator produces :
120 T of nitrogen oxydes (15 Kg/h)
20 T of sulfur oxydes (3,75
(3 75 Kg/h)
5 T of CO (0,62 Kg/h)
6 T of HCl and VOC (0,75 Kg/h)
1 T of dust and PAH (0,125 Kg/h)
300 Kg of heavy metals, including 60 Kg of mercury and cadmium
100 Kg of hexafluorhydric acid
60 mg of dioxins
And 95 000 T of CO2 : 5.300
5 300 km by 1 million of mid size cars (180g/km)
While RESPECTING the legislation, and supposed to reject
only…water vapor
Could people accept these data ?
35
Where local authorities
only speak in %
• Ex: Chambéry ; 100,000 T/y
– 2 600 000 m3/d
•
•
•
•
•
•
•
N2 : 74%
C02 : 10%
02 : 10%
H2 0 : 6%
CO : 0.004%
Dioxins : 0,00000000002%
0 00000000002%
Less than 0.0017 ng/m3, 0,014 ng/y
• In fact, it is true that it is very few: 7 times less than the
legal level
Finally…
• 8 h of control 2x a year, scheduled, no
surprised
i d controls
t l
• The law authorizes 15 x 4h a year of exhaust
gas WITHOUT treatments (to cope with
filtration problems)
36
But get to that point !…
• Are incinerators the only Dioxin
contributors ?
NO !
OK, almost half of the dioxins rejected come from MWI
37
Are the dioxins only present in
the flue gas ?
• NO !!
As we fight and concentrate on the gas phase, now,
almost 3/4 of the emitted dioxins come
from the solid waste from the bottom of the furnace
Are the dioxins only present in the flue gas ?
5.6%
72.6%
18.6%
> 98%
38
• To cope with the future level, we will have
t treat
to
t t the
th solid
lid phase,
h
solid
lid residues
id
and
d
fly ash; not only the gas phase…
• Or avoid any incineration !
But who else ?
•
•
•
•
•
•
•
•
MWI : 255
Home wood combustion : 92
Cables burning (forbidden !) : 40
Iron ore agglomeration industry : 36
Electric steel process : 10
Recycling aluminum fusion : 8
Wastewater treatment plant sludge incineration : 6
Industrial waste incineration : 3
Chemistry,
y, paper
p p industry,
y,
cement industry and biogas from
landfill incineration : less than 1
each
39
PCDD-PCDF production per country, g/y
3981
2744
22 29
S
A
290 334
150 181
39 42 112
DK
SK
HUN
AUS
CH
CAN
D
486 569
NL
UK
661
B
873
F
USA
JPN
Rem 1 : no figures available for China, India, Russia, Brazil…
Rem 2 : considered per capita, positions would change a lot…and
Belgium should appear as the contributor #1
• Except for some countries* one may see that the
main
i contributors
t ib t
are coall resourced
d electric
l t i power
plant countries
* France, as Sweden, Lithuania, Slovenia…mainly
produces electricity from nuclear power plants
plants, with
no greenhouse gas effect, and no dioxins too…
And so, relatively, MWI contribute more
40
People awareness
• ADEME, the French authorityy for environment
and renewable energies says :
• "there is definitely NO place where the exposure
level may be considered as null"
– In rural regions, levels in the soil are commonly 1
ng/kg of dry matter, while it can reach 10 in urban
regions
People awareness
• Water contents : very low as dioxins are
li
lipophilic
hili : usually
ll undetectable,
d t t bl (l
(less th
than
1 pg/l), except OCDD (100 pg/l).
• But they accumulate in the sediments, of
course in the food chain
chain, but they also can
be ‟respread ” in the atmosphere by wind
and waves…
41
• As those molecules are resistant, they
accumulate in the environment so the
concentration WILL increase…
• What
at has
as to be considered
co s de ed as tthe
e security
secu ty
Threshold ?
• Long term impacts on people's health remain
very unknown
• Never forget the levels : BBQ are presented as
without danger because they are supposed to
produce only some pg/y : remember that there is
no threshold !
• Applying a simple security principle
should lead any government to avoid
incineration…
• But
But, are the people really ready to
change their consumer's behaviour ?
42
CONCLUSION
• Science, medicine, epidemiology, laws…
progress at each accident
• But human and social costs are so high...
Bibliography,
iconography,musical credits
– "Agent orange and its associated dioxins : assessment of a
controversy"
t
" ed.
d by
b A
A.L.YOUNG
L YOUNG & G.M.REGGIANI,
G M REGGIANI
elsevier, 1988
– "Mechanisms of formation and destruction of
polychlorinated dibenzo-p-dioxins and dibenzofurans in
heterogeneous systems", critical review, R. ADDINK, K.
OLIE, Env. Sc. & Technol. Vol 29 nr. 6, 1425-1435, 1995
– French, Belgium and Swiss governemental and NGOs’
web sites
43