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 [...]... Environmental Health Criteria Documents and many others – http://www.inchem.org 14 Summary • 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 15 ... scientifically justified and are accepted as the benchmarks against which national measures and regulations are evaluated – http://www.who.nl/index1.htm WHO Global Air Quality Guidelines – http://www.who.int/peh/air/airqualitygd.htm WHO Guidelines for Drinking Water Quality – http://www.who.int/water_sanitation_health/ gdwq/index.html JECFA and JMPR at WHO – http://www who int/pcs/jecfa/jecfa htm http://www.who.int/pcs/jecfa/jecfa.htm... to discriminate by applying different requirement to different countries, unless there is sufficient scientific justification for doing so SPS and TBT (cont’d) Environmental guidelines/standards: additional links WHO Air Quality Guidelines for Europe • SPS and TBT require internationally harmonized standards in order to eliminate food quality standards becoming obstacles of trade • Codex is recognized... Compare the TMDI with the ADI 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 • The need for international food standards • Huge increase in international trade of food commodities in recent years, raising concerns about safety • To reduce barriers to trade . 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. societal matter. WHO Guidelines for DrinkingWHO Guidelines for Drinking Water Quality:Water Quality: provisional guideline valuesprovisional guideline values A provisional guideline value is recommended. 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