guideline derivation std setting II dec 15 compatibility mode

1
Environmental guidelines/standardsEnvironmental guidelines/standards
Dr Leonard RitterDr Leonard Ritter
University of Guelph
Environmental guidelines/standardsEnvironmental guidelines/standards
Dr Leonard RitterDr Leonard Ritter
University of Guelph
Dr Kersten Gutschmidt
World Health Organization
Protection of the Human Environment (PHE)
International Programme on Chemical Safety (IPCS)
Content
guideline versus standard
WHO Air Quality Guidelines
WHO Guidelines for Drinking
Water Quality
WHO Guidelines for Drinking
-
Water Quality
Codex Alimentarius Food Standards
Reliance
on cars
Pressures
Driving
forces
Dependency on chemicals to improve
quality of life; consumption patterns
Toxic emissions; waste generation; water
use, energy use
Environmental health causeEnvironmental health cause effect framework: Factors and action related to effect framework: Factors and action related to
chemicals use.chemicals use.

- promote changes of consumption.
- implement an integrated
product policy.
- set emission limits;
- establish safety procedures;
- prevent accidents.
-
set environmental quality and
Action
Factor
^
Action
Exposure
State
Effect
Chemicals in the environment, food, and
products; urban air quality; climate change
Exposure, intake, and dose of workers
and the public
Morbidity, mortality, and accidents in
workers and general public; poisonings
set

environmental

quality

and
food standards.
- classify and label chemicals ;

- evaluate uses and decide on use
restrictions;
- establish product registers.
- establish Poisons Centres;
- keep stocks of antidotes;
- prepare for responding to
accidents.
Guidelines:Guidelines:
recommendations recommendations
scientificscientific
health (risk) basedhealth (risk) based

g
uidance to
g
overn
g
uidance to
g
overn
Guidelines versus standardsGuidelines versus standards
gggg
ments for standard settingments for standard setting
Standards:Standards:
limit values fixed in lawlimit values fixed in law
considers socioconsiders socio
economic factorseconomic factors
2
Guideline values: Guideline values: threshold substancesthreshold substances
• Evaluate information on toxicity.

• Describe dose-response relationship.
– e.g. NOAEL or LOAEL for the critical effect in
the most relevant study.
• Apply an uncertainty factor.
•
Derive at a tolerable intake (TI)
Derive

at

a

tolerable

intake

(TI)
.
• Estimate exposure route proportions of TI.
• Allocate proportions of TI to media of exposure.
Ó GVs not necessarily represent national or local
exposure situations.
Ó GVs should be adapted to local circumstances.
Guideline values, Guideline values, example: chlorinated hydrocarbons (1)example: chlorinated hydrocarbons (1)
(according to EHC 170)(according to EHC 170)
•• media concentrationmedia concentration
– ambient air: < 0.10 μg/m
3
(indoor air levels are similar).
– drinking-water: 0.003 μg/L to < 0.02 μg/L.

–
food: 0.0018 μg/g (detected only in meat).
– soil: no data.
– consumer products: no data
•• estimates of exposure in estimates of exposure in μμg/kg body weight (bw) per day.g/kg body weight (bw) per day.
Ðambient air 0.034
(bw: 64 kg; breathing: 22 m
3
/day).
Ð
drinking
-
water 0.0007
-<
0.0004
(1.4 L water/day).
Guideline values, Guideline values, example: chlorinated hydrocarbons (2)example: chlorinated hydrocarbons (2)
(according to EHC 170)(according to EHC 170)
Ð
drinking
water

0.0007

0.0004

(1.4

L

water/day).
Ðfood 0.004 (125 g meat composite/day)
ÐTotal intake 0.03 μg/kg bw per day.
•• relative media contribution to total exposurerelative media contribution to total exposure
– outdoor/indoor air: < 0.03 = 85.92% (86%).
– drinking-water: 0.000235 = 0.78% (0.8%).
Guideline values, Guideline values, example: chlorinated hydrocarbons (3)example: chlorinated hydrocarbons (3)
(according to EHC 170)(according to EHC 170)
– food: 0.004 = 13.3 % (13%).
– soil: no data.
– consumer products: no data.
3
•• NOAELNOAEL
– available data on inhalation studies are inadequate.
– data shows that inhalation is the main exposure route for
adults, however, the principal route of intake of the most
exposed group (breast fed infants) is ingestion (of mothers
milk).
Guideline values, Guideline values, example: chlorinated hydrocarbons (4)example: chlorinated hydrocarbons (4)
(according to EHC 170)(according to EHC 170)
– NOAEL is 60 mg/kg bw per day from a long term ingestion
study with renal tubular degeneration observed at higher
doses; 5 days per week feeding study; rat.
Guideline values: Guideline values: nonnon threshold substancesthreshold substances
• Evaluate information on toxicity.
• Describe dose-response relationship.
– e.g. low-dose extrapolation (e.g. linear
extrapolation).
• Derive at a risk estimate.
– e.g. unit risks: cancer risk estimate for

lifetime exposure to a concentration of
lifetime

exposure

to

a

concentration

of

e.g. 1 μg/m
3
(e.g. WHO AQG);
– exposure associated with risks to
develop the disease in question such as
10
-3
, 10
-4
(e.g. WHO Drinking Water
Guidelines).
Ó no GVs for non-threshold substances by
WHO.
A
IR
A
IR

WHO Air Quality Guideline: Substances consideredWHO Air Quality Guideline: Substances considered
Organic air pollutants:
Acrylonitrile, Benzene, Carbon disulfide, 1,2-
Dichloroethane, Dichloromethane, Formaldehyde,
Polynuclear aromatic hydrocarbons (carcinogenic
fraction), Styrene, Tetrachloroethylene, Tolouene,
Trichloroethylene, Vinyl chloride
Inorganic air pollutants:
Arsenic, Asbestos, Cadmium, Carbon monoxide,
Chromium, Hydrogen sulfide, Lead, Manganese,
Mercury, Nickel, Nitrogen oxides,
Ozone/photochemical oxidants, Particulate matter,
Radon, Sulfur oxides, Vanadium. extrapolation).
4
WHO Air Quality Guideline: criteria for inclusion of substancesWHO Air Quality Guideline: criteria for inclusion of substances
• sources, levels, and routes of exposure.
• kinetics and metabolism
• LOAELs and/or NOAELs for humans, animals,
and plants.
• Uncertainty factors.
IARC l ifi ti f i
•
IARC
c
l
ass
ifi
ca
ti
on o

f
carc
i
nogens.
• Quantitative assessment of carcinogenic
potency from animal studies.
• Unit lifetime risk from human epidemiological
data.
• Ecological effects
WHO Air Quality Guideline: Classical Air PollutantsWHO Air Quality Guideline: Classical Air Pollutants
CompoundCompound Guideline valueGuideline value Averaging timeAveraging time
CO 100 mg/m
3
15 min
60 mg/m
3
30 min
30 mg/m
3
1 h
10 mg/m
3
8 h
Ozone 120
μ
g/m
3
8h
NO
2

200
μ
g
/m
3
1h
2
μ
g
40-50
μ
g/m
3
annual
SO
2
500
μ
g/m
3
10 min
125
μ
g/m
3
24 h
50
μ
g/m
3

annual
Particles no GV (dose-response curve)
0.5 to 1.0
μ
g/m
3
annual
Comparison of WHO Air Quality Guidelines with national Comparison of WHO Air Quality Guidelines with national
ambient air quality standards:ambient air quality standards:
Country 1 hr 24 hrs Annual 1 hr 24 hrs Annual 1 hr 8 hrs 1 hr 8 hrs 24 hrs annual 24 hrs Annual
WHO -0.130.050.20-0.0430.010.0-0.12
USA - 0.37 0.08 - - 0.10 40.0 10.0 0.24 - - - 0.15 0.05
Japan0.260.11 0.06 22.80.12
Netherland
s
0.760.23-0.18 40.06.00.12
Australia
0.44
0.16
-
0.30
0.12
-
34.3
11.4
0.24
0.10

TSP PM10SO2 NO2 CO O3
Australia

0.44
0.16
0.30
0.12
34.3
11.4
0.24
0.10
Mexico 0.40 15.0
Taiwan0.780.26 0.10-22.9
Canada0.820.27-0.400.20-15.06.00.10
Germany 0.14 0.0830.0
Thailand 0.78 0.30 0.14 0.32 - - 34.2 10.3 0.20 - 0.33 0.10 0.12 0.05
5
DRINKINGDRINKING WATERWATER
DrinkingDrinking waterwater
An established goal of WHO and its Member states
is that:
all people, whatever their stage of
development and their social and economic
development

and

their

social

and

economic

conditions, have the right to have access to
an adequate supply of safe drinking-water.
What does ‘safe’ mean in this context?What does ‘safe’ mean in this context?
‘Safe’ refers to a water supply that is:
• of a quality which does not represent a
significant health risk;
• is of sufficient quantity to meet the domestic
needs;
iilblti l
•
i
s ava
il
a
bl
e con
ti
nuous
l
y,
• is available to all the population; and
• is affordable.
6
WHO Guidelines for DrinkingWHO Guidelines for Drinking Water QualityWater Quality
Volume 1- recommendations:
• criteria used in selecting microbiological, chemical and
radiological contaminants.
• approaches used to derive the GVs.

• brief information supporting GVs recommended or why
no GV has been given.
Volume 2 - health criteria and other supporting
information:
information:
• Elaborates greatly on the health risk assessment of
microbial and chemical contaminants presented in
Volume 1.
Volume 3 - Surveillance and control of community
supplies:
• deals specifically with small communities in developing
countries.
Guideline value for chemicalsGuideline value for chemicals
• Represents the concentration of a chemical constituent that
does not result in any significant risk to health of the
consumer over a lifetime of consumption.
• Short-term deviations above the guideline values does not
necessarily mean that the water is of unsuitable
consumption.
• GVs should not be regarded as implying the quality of
drinking water may be degraded.
• When a GV is exceeded, the authority responsible for public
health should be consulted for suitable action.
• When developing national standards based on the GVs, it
will be necessary to take into account geographical, socio-
economic, dietary and other conditions affecting potential
exposure.
Guideline value for chemicals (cont’d)Guideline value for chemicals (cont’d)
•• GVs must be practical and feasible to implement.GVs must be practical and feasible to implement.
– GVs are not lower than limit of detection under routine

laboratory operating conditions.
– GVs are recommended only when control techniques are
available to remove or reduce contaminants to the
desired level.
•• No GVs for the aesthetic acceptability of the water.No GVs for the aesthetic acceptability of the water.
•• Some of the agents evaluated are essential for life. No Some of the agents evaluated are essential for life. No
attempt was made to define minimum desirable attempt was made to define minimum desirable
concentrations.concentrations.
•• GVs are set at a level to protect human health; they may GVs are set at a level to protect human health; they may
not be suitable for the protection of aquatic life.not be suitable for the protection of aquatic life.
•• GVs apply to bottled water and ice but do not apply for GVs apply to bottled water and ice but do not apply for
mineral waters, which are regarded as beverage .mineral waters, which are regarded as beverage .
7
WHO Guidelines for DrinkingWHO Guidelines for Drinking Water QualityWater Quality
• acute problems are rare
• chronic/cumulative problems are more common
• GV in concentrations in mg/litre for:
–
inorganic substances
–
inorganic

substances
– organic substances
– pesticides
– disinfectant and disinfectant by-products
WHO Guidelines for DrinkingWHO Guidelines for Drinking Water Quality:Water Quality:
derivation of GVs: threshold substancesderivation of GVs: threshold substances
• review of scientific database
• estimation of tolerable daily intake (TDI)

for exposure from all sources
• adjustment to body weight
• adjustment for daily drinking-water
consumption
• allocation of percentage of TDI (default
value is 10%) to drinking water intake.
WHO Guidelines for DrinkingWHO Guidelines for Drinking Water Quality:Water Quality:
derivation of GVs: nonderivation of GVs: non threshold substancesthreshold substances
• 60 kg adult drinking 2 litres of water per day for
70 years
• use of linearized multistage model
• calculation of drinking water concentrations
associated with an excess cancer risk of:
4
–
10
-
4
(additional cancer cases per 10 000 of
the population)
–10
-5
(additional cancer cases per 100 000 of
the population)
–10
-6
(additional cancer cases per 1 000 000
of the population)
Ð WHO does not define “acceptable risk”. This is
a national, societal matter.

WHO Guidelines for DrinkingWHO Guidelines for Drinking Water Quality:Water Quality:
provisional guideline valuesprovisional guideline values
A provisional guideline value is recommended
where:
• there is evidence of a potential hazard but
data is limited and the UF is larger than
1000.
• the calculated GV is below the anal
y
tical
y
quantification limit.
• the calculated GV is below the level that
can be achieved by water treatment.
• the calculated guideline will be exceeded
as a result of water disinfection.
• for carcinogens where a guideline value
equivalent to 10
-5
lifetime excess cancer
risk is not feasible.
8
FOODFOOD
9
The Codex Alimentarius CommissionThe Codex Alimentarius Commission
The Codex Alimentarius Commission was created in
1963 by FAO and WHO to develop food standards,
guidelines and related texts such as codes of practice
under the Joint FAO/WHO Food Standards Programme.
Codex Alimentarius CommissionCodex Alimentarius Commission

Main objectives are:
• to protect the health of consumers and ensuring
fair practices in food trade;
• to promote coordination of food standards work
undertaken by IGOs and NGOs.
•
to determine priorities initiate and guide the
•
to

determine

priorities
,
initiate

and

guide

the

preparation of draft standards;
• to finalize standards and, after acceptance by
governments, publish them.
• to amend published standards, after appropriate
survey in the light of developments.
Subsidiary bodies of the Codex Alimentarius CommissionSubsidiary bodies of the Codex Alimentarius Commission
 Coordinating Committees
– (sub) regions coordinate food standards activities, including the

development of regional standards.
 Codex Committees
– prepare draft standards for submission to the Codex Alimentarius
Commission.
Commodity Committees
–
Commodity

Committees
• responsible for developing standards for specific foods or food
classes. (‘vertical committees’).
– General Subject Committees
• are so called because their work has relevance for all Commodity
Committees, since this work applies across the board to all
commodity standards (‘horizontal committees’).
Codex General Subject CommitteesCodex General Subject Committees
Food Additives
and Contaminants
Pesticide
Residues
Residues of
Veterinary Drugs
Others, including
General Principles
Codex
general subject
committees
and

Contaminants

(CCFAC)
Residues
(CCPR)
Veterinary

Drugs
in Foods (CCRVDF)
General

Principles
,
Food Labelling, &
Food Hygiene
Among other things, Codex Committees review draft standards
provided based on advice of independent scientific expert bodies to be
submitted to the Codex Alimentarius Commission.
10
Risk analysisRisk analysis
• Risk assessment – primarily the responsibility of
scientific committees
• Risk management – primarily the responsibility of
Codex committees
Codex committees
• Risk communication – between risk assessors and
managers, and with the public
• Established in 1955, JECFA considers mainly chemical
and toxicological aspects of additives, contaminants and
residues of veterinary drugs in food.
• JECFA members are experts appointed in their own right
and not as government representatives.

• JECFA is independent from the Codex Alimentarius
Commission
Joint FAO/WHO Expert Committee on Food Additives (JECFA)Joint FAO/WHO Expert Committee on Food Additives (JECFA)
Commission
.
• CCFAC and CCRVDF identify food additives,
contaminants and veterinary drug residues that should
receive priority evaluation and refer them to JECFA.
• Reports of toxicological evaluations are published
• JECFA also provides scientific advice directly to FAO
and WHO Member States.
• Established in 1955, JECFA considers chemical,
toxicological and other aspects of contaminants and
residues of veterinary drugs in food.
• JECFA members are experts appointed in their own right
and not as government representatives.
Joint FAO/WHO Expert Committee on Food Additives (JECFA)Joint FAO/WHO Expert Committee on Food Additives (JECFA)
• Scientific evaluation of:
– chemical additives in food
– residues of veterinary drugs in food
– food contaminants
• JECFA establishes Acceptable Daily Intakes (ADIs).
• JECFA recommends MRLs for veterinary drugs.
• NOAEL divided by uncertainty factor
• most appropriate study; most sensitive species
• mg/kg of human body weight that can be ingested
daily over a lifetime without appreciable health risk
Ð
The ADI is used b
y

Codex Alimentarius to set
Joint FAO/WHO Expert Committee on Food Additives (JECFA)Joint FAO/WHO Expert Committee on Food Additives (JECFA)
y
permissible levels in food.
Ð food additives that have been ‘toxicologically cleared’
by JECFA
11
• Established in 1963, JMPR should recommend maximum residue
limits (MRLs) for pesticides in food as well as methods of
sampling and analysis.
• JMPR members are experts appointed in their own right and not
as government representatives.
• JMPR is independent from the Codex Alimentarius Commission.
Joint FAO/WHO Meeting on Pesticide Residues (JMPR)Joint FAO/WHO Meeting on Pesticide Residues (JMPR)
• FAO appointees draft MRLs.
• WHO appointees conduct toxicological evaluations.
• Reports and evaluations are published.
• CCPR identifies those pesticides requiring priority evaluation.
After JMPR evaluation, CCPR discusses recommended MRLs
and, if acceptable forward them to the Codex Alimentarius
Commission for adoption as Codex MRLs.
Scientific committeesScientific committees
• Provide recommendations that serve as the basis
for Codex standards
• Administered by the World Health Organization
(WHO), headquartered in Geneva, and the Food
and A
g
riculture Or
g

anization of the United
gg
Nations (FAO), headquartered in Rome
• Composed of scientists who are invited on the
basis of their scientific expertise
WHO participantsWHO participants
• Experts employed by universities and governments
• Evaluate toxicological and related data
• Establish “acceptable” or “tolerable” intakes for
the chemicals bein
g
evaluated
,
ex
p
ressed as a
g,p
“dose” in terms of mg (or μg)/kg body weight per
day
Committee relationshipsCommittee relationships
• JECFA advises CCFAC on food additives and
contaminants and CCRVDF on residues of
veterinary drugs
• JMPR advises CCPR on pesticide residues
JECFA – Joint FAO/WHO Expert Committee on Food Additives
JMPR – Joint FAO/WHO Meeting on Pesticide Residues
CCFAC – Codex Committee on Food Additives and Contaminants
CCRVDF – Codex Committee on Residues of Veterinary Drugs in
Foods
CCPR – Codex Committee on Pesticide Residues

12
MRLs are based on:MRLs are based on:
• Good agricultural practice.
• Average consumption of the commodities.
•
Food processing
Maximum Residue Levels (MRLs)Maximum Residue Levels (MRLs)
•
Food

processing
.
• Variation of residue levels with time.
• The percentage of a given commodity that
is treated.
MRLs for pesticides in foodMRLs for pesticides in food
MRLs for veterinary drugs in foodMRLs for veterinary drugs in food
13
ADIsADIs
‘First’ health risk assessment for pesticides‘First’ health risk assessment for pesticides
• RA framework: Hazard identification, dose-response
relationship, exposure assessment, risk characterisation.
• Calculate the Theoretical Maximum Daily Intake (TMDI)
base on ‘cultural’ or ‘regional’ diets by summing-up MRLs
of all commodities treated
•
Compare the TMDI with the ADI
Compare

the

TMDI

with

the

ADI
.
• At the international level, the TMDI and the resulting risk
estimates are a convenient screening tool to identify
residues which might be of health concern under current
modes of application.
• If available, better information should be used to obtain a
better estimate of dietary exposure.
• Huge increase in international trade of food
commodities in recent years, raising concerns
about safety.
• To reduce barriers to trade.
• Need for risk assessment advice by governments.
The need for international food standardsThe need for international food standards
• To harmonize risk assessments, reducing
duplication of effort.
14
The Agreement on the Application of Sanitary and The Agreement on the Application of Sanitary and
Phytosanitary Measures (SPS)Phytosanitary Measures (SPS)
• SPS acknowledges that governments have the right
to take sanitary and phytosanitary measures
necessary for the protection of human health.
• However, the SPS Agreement requires them to apply

those measures only to the extent required to protect
hhlth
h
uman
h
ea
lth
.
• The SPS doses not permit Member Governments to
discriminate by applying different requirement to
different countries, unless there is sufficient scientific
justification for doing so.
The Agreement on Technical Barriers on Trade (TBT)The Agreement on Technical Barriers on Trade (TBT)
• TBT seeks to ensure that technical regulations and
standards do not create unnecessary obstacles of trade.
• The Codex Alimentarius Commission is recognised as the
source of international food standards.
•
Countries can establish stricter standards but must
Countries

can

establish

stricter

standards
,
but

must

scientifically justify them.
SPS and TBT (cont’d)SPS and TBT (cont’d)
• SPS and TBT require internationally harmonized
standards in order to eliminate food quality
standards becoming obstacles of trade.
• Codex is recognized as the source of international
food standards for food additives, veterinary drugs,
pesticide residues and contaminants
pesticide

residues

and

contaminants
.
• Codex standards are considered scientifically
justified and are accepted as the benchmarks
against which national measures and regulations
are evaluated.
WHO Air Quality Guidelines for Europe
– />WHO Global Air Quality Guidelines
– />WHO Guidelines for Drinking Water Quality
– />gdwq/index.html
JECFA and JMPR at WHO
–
http://www who int/pcs/jecfa/jecfa htm

Environmental guidelines/standards: additional linksEnvironmental guidelines/standards: additional links
http://www
.
who
.
int/pcs/jecfa/jecfa
.
htm
– />JECFA and WHO at FAO
– />– />pm_jmor.htm
Food Safety at WHO
– />Environmental Health Criteria Documents
and many others
–
15
SummarySummary
• a guideline is not necessarily a standard.
• international guidelines are available for
various media, chemicals, and commodities to
assist countries in the process of standard
setting
setting
.
• all information is available on the www.