Revision of the Carcinogens and Mutagens Directive – Why do we need it?
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Transcript of Revision of the Carcinogens and Mutagens Directive – Why do we need it?
wien.arbeiterkammer.at
Revision of the Carcinogens and Mutagens Directive – Why do we need it?
Christoph Streissler
Arbeiterkammer Wien (Chamber of Labour, Vienna, Austria)
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Overview
hazard – exposure – risk
starting point: a high level of protection
dose-response-relationship
threshold non-threshold effects
health based limit values risk based limit values
revision of the carcinogens directive (CMD): what lies ahead
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Terms
chemical agent: any chemical element or compound, on its own or admixed […], used or released […] by any work activity, whether or not produced intentionally and whether or not placed on the market;
hazard: intrinsic property of a chemical agent with the potential to cause harm;
risk: likelihood that the potential for harm will be attained under the conditions of use and/or exposure.
exposure: concentration of an agent with which a person or population comes into contact (chemical agents: inhalation and dermal exposure)
risk = hazard × exposure
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
High level of protection
“A high level of human health protection shall be ensured in the definition and implementation of all Union policies and activities.” (TFEU, Article 168)
A high level of protection – in the context of chemicals – means to:
“ … ensure that, under reasonably foreseeable conditions, human health and the environment are not adversely affected.” (REACH Regulation, recital 16)
“… the objective in establishing OELs is to set limits for exposure via the airborne route such that exposure, even when repeated on a regular basis throughout a working life, will not lead to adverse effects on the health of exposed persons and/or their progeny at any time (as far as can be predicted from the contemporary state of knowledge).” (SCOEL: Methodology for the Derivation of Occupational Exposure Limits, v.6)
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Can zero risk be achieved?
“… although in some cases scientific knowledge may not be such that a level of exposure to a chemical agent can be established below which risks to health cease to exist, a reduction in exposure to these chemical agents will nonetheless reduce these risks.” (CAD, recital 20)
“… the risk to humans and the environment can be considered to be adequately controlled if the estimated exposure levels do not exceed the appropriate DNEL. For those human effects for which it was not possible to determine a DNEL, a qualitative assessment of the likelihood that effects are avoided when implementing the exposure scenario shall be carried out.” (REACH regulation, Annex I, para 6.4 and 6.5, abridged)
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Dose response relationship
Source: Factsheet Grenzwerte am Arbeitsplatz – Grundlagen und Anwendung. SUVA 2012, modified
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Threshold versus non-threshold effects of chemical agents
Chemicals which exhibit adverse effects only if their uptake exceeds a certain amount are said to have a threshold.This threshold value may be high (e.g. Acetone) or low (e.g. Chlorine), but in any case, exposure below the threshold value does not lead to adverse effects.(typically: acutely toxic or corrosive chemicals)
Chemicals which damage the genetic material of cells do not exhibit such a threshold. Already one single molecule can lead to a damage that develops into a cancer. However the potential to cause cancer may be stronger or weaker.(typically: carcinogenic and mutagenic chemicals)
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Chemicals exhibiting a threshold effect
dose effect relationship based on experimental values
LOAEL: Lowest Observed Adverse Effect Level – lowest dose at which some adverse effect could be detected.
NOAEL: No Observed Adverse Effect Level
Source: as above
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Chemicals exhibiting no threshold effect
dose effect relationship based on experimental values, but only at comparatively high risks
POD: Point Of Departure
extrapolation to dose 0 (linear by default)
Source: as above
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Mode of action of carcinogenesis
Experimentally, only risks above about 10% can be observed; hence extrapolation to lower doses and lower risks is necessary
Some carcinogens exhibit threshold behaviour. In order to decide if this is the case for a given carcinogen, the mode of action (mechanism of carcinogenesis) has to be known
genotoxic action: no safe level
other modes (e.g. via chronic inflammation) may exhibit a threshold and hence a safe level
If mode of action is not well established, genotoxic carcinogenesis and hence no existence of a threshold should be assumed by default
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Threshold versus non-threshold effects: OSH directives
OSH directives do not explicitly distinguish between threshold and non-threshold effects but between carcinogens and mutagens on the one hand and “other” chemical agents on the other hand.
CAD (Chemical Agents Directive): indicative occupational exposure limit values for the protection of workers from chemical risks, based on scientific data (health based values)
CAD: Binding Occupational Exposure Limit Values (BOELV): in addition reflect feasibility factors: only lead and its inorganic compounds.
CMD (Carcinogens and Mutagens Directive): binding occupational exposure limit values – BOELV (irrespective of mode of action)
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Threshold versus non-threshold effects: REACH regulation
in theory: REACH regulation makes a more precise distinction
if a threshold value exists: the risk to humans and the environment can be considered to be adequately controlled if the estimated exposure levels do not exceed the appropriate DNEL:health based limit value = zero risk
If it was not possible to determine a DNEL [= no threshold value exists], a qualitative assessment of the likelihood that effects are avoided when implementing the exposure scenario [= applying the risk management measures appropriately] shall be carried out:risk based approach, but obscure
German and Dutch risk based concepts are more precise
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Risk based OELVs
Source: Henning Wriedt, modified
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
CMD in a nutshell
Directive 2004/37/EC on the protection of workers from the risks related to exposure to carcinogens or mutagens at work (= CMD)
covers carcinogens and mutagens (category 1 and 2 = categoryCLP 1A
and 1B) and substances or processes listed in annex I
obligations of employer: determination and assessment of risks; replacement (“substitution”) of substances or reduction; prevention of exposure following a hierarchy of steps; information and training for workers
health surveillance, keeping of records
annex I: additional substances or processes covered
annex III: binding occupational exposure limit values: 3 substances
wien.arbeiterkammer.atChristoph Streissler: Revision of the Carcinogens and Mutagens Directive. Stockholm, 27-28 June 2013
Revision of the CMD: what lies ahead
current situation:
three BOELVs that take into consideration feasibility as of 25 years ago;
benzene: BOELV of 3,25 mg/m3: risk approx. 5 in 1000
vinyl chloride monomer: BOELV of 7,77 mg/m3: risk approx. 3 in 1000
what lies ahead:
methodology for deriving limit values (NOT based on cost benefit analysis)
more BOELVs, risk based
better monitoring in order to reduce discrepancies between MS
inclusion of reprotoxic substances (workers’ demand)