1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif 1212570_28446780.jpg logo_mu_cerne.gif trojlogo.gif Introduction to Ecotoxicology Ludek Blaha, Jakub Hofman, Klara Hilscherova & co. www.recetox.muni.cz 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Lecture objectives and aims Introduction to ecotoxicology outline - What is ecotoxicology - principles and hierarchy - - Subject of studies in ecotoxicology - Ecotoxicology vs. environmental chemistry - Ecotoxicology as a science - - Risk Assessment and the role of Ecotoxicology - - Practical applications of ecotoxicology – REACH EU 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif CHEMICAL ENTERS THE ENVIRONMENT Bioavailable fraction “EXPOSURE” acute chronic Toxikokinetics biotransformation bioactivation excretion / sequestration Target site “EFFECT” LEVELS, FATE, PROCESSES CHEMICAL ENTERS THE ORGANISM biomonitoring 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Chemicals in the environment Do you believe that chemicals in products sold to consumers have been proven safe? Think again Most chemicals in modern use have simply not been tested for their impacts on human, even very basic effects. … what about the effects in nature, then ? 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Chemicals in the environment •Rats exposed in the womb to a single low dose of a widespread brominated flame retardant become hyperactive and have decreased sperm counts… • •Experiments with dioxin and similar compounds provide support for the assumption that cancer risks mediated by the aryl hydrocarbon receptor are additive. Previously untested for cancer, this assumption underpins a standard way of estimating exposure risks to these compounds. The results reinforce the need to focus health standards on mixtures rather than single compounds. • •At exposure levels within the range experienced by the general public, the phthalate DBP reduces expression of genes necessary for testosterone synthesis in fetal rats… • •Eutrophication of frog ponds is linked to epidemics of frog deformities, because it creates conditions that lead to higher rates of parasitic infections of tadpoles. The parasitic infections in turn disrupt normal development of the tadpoles' limb buds during metamorphosis. • OSF%20Hardback%20Large 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif •…that studies now prove that compounds like DDT and PCBs are not risk factors for breast cancer. • •Reality • •Several recent studies indicate there is no association between PCBs and DDE (a persistent break-down product of DDT) levels in adult women and their risk of breast cancer. • •None overcome severe obstacles that epidemiology faces when confronting mixtures. • •None address the question of whether developmental exposure (fetal or pubertal) increases breast cancer risk. More... OSF%20Hardback%20Large Chemicals in the environment 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif INDIRECT effects of chemicals in the environment: EUTROPHICATION www.epa.gov 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif INDIRECT effects of chemicals in the environment: EUTROPHICATION www.wikipedia.com 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Environmental (chemical) problems 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Environmental (chemical) problems Mixing oceans -> functioning of the globe cooling down the atmosphere [Nature 447, p.522, May 31, 2007] Marine life supplies up to 50% of the mechanical energy required worldwide to mix cool waters from the surface to deep layers [Dewar, Marine Res 64:541 (2006)] 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif • • • • • • • • • • • ISO 14001 Ecotoxicology today ? > 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif •Aim: to maintain the natural structure and function of ecosystems • •Definitions: §ecotoxicology is concerned with the toxic effects of chemical and physical agents on living organisms, especially on populations and communities within defined ecosystems; it includes the transfer pathways and their interactions with the environment §science of contaminants in the biosphere and their effect on constituents of the biosphere, including humans’ (Newman & Unger, 2002) §science that provides critical information on effects of toxic compounds on living organisms which SERVE various practical aims (environmental protection) ECOTOXICOLOGY – aims … 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Cause – effect paradigm ... •‘What is there which is not a poison? • •All things are poison and nothing without poison. •Solely the dose determines that a thing is not a poison. • 2 Paracelsus (1493 - 1541) 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Ecology Substances & their mixtures Models ECOTOXICOLOGY – a synthetic science 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Ecotoxicology: ecological hierachy 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Ecotoxicology: approaches, hierarchy • – Local Global Value Other Sciences Other Technologies Other Laws and Regulations Other Social Needs 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Ecotoxicology: BASIC SCIENCE ? few examples … 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif 1962 © Patuxent Wildlife Refuge, MA, USA http://www2.ucsc.edu/scpbrg/ Možné negativní důsledky chemického znečištění pro organismy poprvé přinesla do širšího povědomí kniha S.S. 1962 - spojila zřejmý úbytek populací ptáků („charismatické druhy“) s používáním DDT - pesticid proti komárům (a přenášeným chorobám) - i přes celosvětový zákaz (tzv. Stockholmská úmluva OSN - obdoba Kjotského protokolu) je jeho výroba velmi levná: užití dodnes v Africe, Indii … od 40.let považován za zcela neškodný a zázračný („netoxický“) …. 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Bitman et al. Science 1970, 168(3931): 594 Biochemistry bird carbonate dehydratase In vivo: shell thinning In situ: bioaccumulation -> bird population decline Možný mechanismus byl navržen až po řadě let - inhibice ptačí karbonátdehydratázy v žláze tvořící skořápku vajíčka (BTW - enzym, který v našich krvinkách zajišťuje přeměnu CO2 na HCO3z tkání - in vivo -> in situ Proč tento obrázek? - 1) až za 30 let od uvedení na trh se poznalo co vlastně DDT dělá …, 2) ukázka jak se malá změna na biochemické úrovni promítne až na úroveň ekosystémů … 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Kidd, K.A. et al. 2007. Collapse of a fish population following exposure to a synthetic estrogen. Proceedings of the National Academy of Sciences 104(21):8897-8901 Controls +Ethinylestradiol 5 ng/L (!) 7 years 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif •ECOLOGY vs ECOTOXICOLOGY • •Key / Keystone species •dramatic changes in all community – example: FISH ! nature03962-f1 Knight et al., NATURE (2005) 437: 880 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Knight et al., NATURE (2005) 437: 880 nature03962-f2 No. of dragonflies 3 size categories (small/med/large) nature03962-f5 „Plant reproduction“ (pollination activities of bees) 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Ecotoxicology WHAT IS IT GOOD FOR ? SOLVING PRACTICAL PROBLEMS 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Starting point: Prevention and reduction of environmental load Source-directed measures Limits Source-directed policy Starting point: Prevention of adverse effects Effect-directed policy Effect-directed measures EQS (Env. Quality Standards) Environmental policy: Limitations of sources and effects 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Atmospheric Deposition Erosion & Runoff Untreated discharges Predicted Environmental Concentration (PEC) bosmina FISH Laboratory (and field) studies Ecotoxicity tests sample56 lab2 faCTORY1 WWTP j0173962 … to derive effective concentrations Exposure (resulting from load) Effects (what exposures cause effects ?) Cause – effect & Risk assessment 2 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Exposure assessment •Purpose: assessment or prediction of the environmental concentration of a chemical •Method: –monitoring and/or prediction (models) –accounting for emissions, pathways and rates of movement of the substance, its transformation and degradation –point sources and diffuse sources •Result: –Environment: Predicted Environmental Concentration - PEC (or MEASURED Environmental concentration) –Human: Estimated Daily Intake - EDI CRA4 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif EFFECTS ASSESSMENT = Ecotoxicology 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif RETROSPECTIVE PROSPECTIVE DISASTERS PREDICTIONS for future MIXTURES OF CHEMICALS / CONTAMINATED ENVIRONMENT INDIVIDUAL TOXICANTS Time: NOW ! Ecotoxicology: problems and approaches 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif RETROSPECTIVE PROSPECTIVE Bioassessment Field assessment Monitoring Bioassessment Field assessment Monitoring Lab studies Lab studies Simulated small ecosystems DISASTERS PREDICTIONS for future Time: NOW ! Ecotoxicology: problems and approaches Most common in practice 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif 1 Bioassays - single / multiple species - acute / chronic effects - standardized (practical) vs. experimental (research) Simulation of the ecosystem - major trophic levels - producers - consumers - destruents figure4 Eisenia_fetida scenedesmus_quadricauda_upr Ecotoxicology – methods 1: Laboratory studies 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif auto0 AcuteToxScheme_RM HaF-adult arenic~4 Daphnia Dania pict Cu addition Effect concentrations expressed in total/dissolved Cu Extrapolation = PNECs or EQCs expressed in total / dissolved Cu Ecotoxicology – laboratory studies – experimental design 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif 50 100 LC50 [concentration] in mg/L or % effluent Threshold: No Observed Effect Concentration (NOEC) Laboratory ecotoxicology – data and results 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Expensive & time consuming (e.g. Pesticide testing) Variable results (natural variability …) Higher ecological relevancy 1 1 figure4 Ecotoxicology – methods 2: Micro & Mesocosms 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif … fairly complex issue (geology, climate, chemistry, biology ..) Ecotoxicology mixes with Ecology figure4 figure4 figure4 figure4 Ecotoxicology – methods 3: Field assessment / biomonitoring 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Notes on practical testing •Testing chemicals –Traditional / bioassays developed to assess chemicals –Standardized approaches –Limited ecological relevance •often acute tests only •„too standardized…“ •does not assess bioavailability •no consideration of mixture effects •no consideration of specific modes of action • •Testing toxicity of natural matrices –Rather new in ecotoxicology – many open challenges –More complex and more complicated •„cause-effects“ often not clear (natural variability …) – 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Reminder …. effect assessment: results = effective concentrations for few representatives 50 100 LC50 [concentration] in mg/L or % effluent Threshold: No Observed Effect Concentration (NOEC) 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif How to extrapolate ecotox data to real ecosystems ? Me in sediment: ºS-OMe MeS Me in porewater MeZ+ MeLx Me in sediment: ºS-OMe MeS Water birds Planktivore Piscivore Air Water 1 2 3 3 3 3 4 4 4 4 5 5 5 5 3 Grazer 5 Phytoplankton 4 4 Filter feeders 4 3 6 Benthos 8 8 4 5 Phytoplankton Zooplankton Benthic feeder 7 4 4 Insectivore Insect 9 4 4 MeZ+ MeLx MeZ+ 6 6 6 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Effects assessment Data Assessment factor L(E)C50 short-term toxicity tests NOEC for 1 long-term toxicity test NOEC for additional long-term toxicity tests of 2 trophic levels NOEC for additional long-term toxicity tests of 3 species of 3 trophic levels 1000 100 50 10 Protection level: 95% Ecotoxicological data Species sensitivity distribution (SSD) HC5 = 95% protection level [C] Assessment / Extrapolation factors PNEC 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Environmental quality criteria Risk assessment: scientific basis for establising EQC ‘Hazard’ identification Data compilation Exposure assessment PEC Effect assessment PNEC Risk characterisation PEC/PNEC < 1 > 1 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif Practical example for ecotoxicologist European strategy how to deal with chemicals 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif EU and risk assessment EU%2520Flag •± 40 Directives or Regulations concerning the evaluation and management of the dangers/risks associated with chemical substances –Regulation EEC 793/93 –Existing substances –Dir. 67/548/EEC – New substances –Dir. 98/8/EC – Biocides / Plant Protection Products –Further Directives – E.R.A. of new pharmaceuticals 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif •Existing substances – –100196 substances in EINECS –2747 HPVCs (High Production Volume Chemicals) •14% minimum data-set (base-set) •65% less than base-set •21% no toxicity data –Various priority lists •Aquatic hazard (EU Water framework directive) •Endocrine disruptors •…. EU and risk assessment 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif •REACH Registration, Evaluation and Authorisation •of Chemicals –27-2-2001: White Paper on the Strategy for Future Chemicals Policy –23-10-2003: Commission’s proposal REACH –December 2008: Pre-registration mandatory (all chemicals in EU must be registered at ECHA European Chemicals Agency (http://echa.europa.eu) 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif EU toekomst: REACH EU%2520Flag Chemicals 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif REACH: aims & timing EU%2520Flag •Major goals –Protection of man and the environment –Increase competiveness of EU chemical industry –Increase transparency –Avoid fragmentation of market –Integration with international policies –Reduction use of test animals • •Approach –Industry is responsible – provides data • •30000 existing substances •0-3 year (2010): all HPVC and CMR substances (~ 3000) •4-6 year (2013): all 100-1000 t/y substances •7-11 year (2018´): all 10-100 and 1-10 t/y substances 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif REACH: data type? EU%2520Flag •Physico-chemical properties, e.g.: –Vapour pressure, boiling point, Kow,… • •Human toxicology, e.g.: –Acute and chronic toxicity, skin irritation, carcinogenity,… • •Environment/ Ecotoxicological information, e.g.: –Acute and/or chronic toxicity for aquatic organisms, biodegradation, … • • 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif REACH: situation 2010 EU%2520Flag •Original plan (2007-2010) –R.A. for ~ 3000 HPVC and CMRs – –Situation 2010 •~ 200 substances RA status •~ 150 draft RA reports •~ 50 final RA reports – • 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif REACH: how many substances EU%2520Flag 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif REACH: costs EU%2520Flag 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif REACH: testing costs EU%2520Flag 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif REACH: test and cost reduction? EU%2520Flag chemicals1 MoneyCalcul%2520EURO%2520100%2520A MoneyCalcul%2520EURO%2520100%2520A MoneyCalcul%2520EURO%2520100%2520A MoneyCalcul%2520EURO%2520100%2520A MoneyCalcul%2520EURO%2520100%2520A MoneyCalcul%2520EURO%2520100%2520A MoneyCalcul%2520EURO%2520100%2520A MoneyCalcul%2520EURO%2520100%2520A MODELS, QSAR 1212569_21823227.jpg logo_mu_cerne.gif trojlogo.gif REACH: implications EU%2520Flag •Total: 2,8 to 5,6 billion € • •Industry pays •Test costs (50-60% of total cost): •86% for HH tests •14% for environment tests •0% for analyses •Manpower and expertise? •Tests •Risk assessments •Evaluations – •Financial and time pressure: danger for ‘hazard-based’ instead of ‘risk-based’ conclusions