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(Click for frequent words.) 64 pollutants emitted 63 gaseous pollutants 63 nitrous oxides 63 gases emitted 63 Carbon Dioxide CO2 62 Particulate Matter PM 62 tailpipe pollutants 62 Carbon dioxide CO2 62 harmful gasses 62 nitrogen oxide NOx emissions 61 NOX emissions 61 nitrogen oxides NOx emissions 61 Nitrogen dioxide 61 nitrogen oxides carbon monoxide 61 unburned hydrocarbons 61 particulate matter sulfur dioxide 61 hydrogen sulphide H2S 61 sulfur dioxides 61 particulate emissions 61 harmful particulates 60 Sulphur dioxide 60 diesel particulates 60 potent greenhouse gas 60 co2 60 nitrous oxide N2O 60 sulphate aerosols 60 biomass combustion 59 harmful byproducts 59 harmful tailpipe emissions 59 gasses emitted 59 nitrous oxide emissions 59 soot particulates 59 Greenhouse gasses 59 Sulfur compounds 59 combustion 59 greenhouse gasses 59 combustion byproducts 59 Nitrogen oxide 59 hydrocarbons carbon monoxide 59 N2O emissions 59 Co2 59 smog forming pollutants 58 Nitrogen oxides 58 Particulates 58 SOx emissions 58 co2 emissions 58 sooty particles 58 nitrogen oxides NOx 58 sulfur dioxide SO2 58 CO -2 emissions 58 ozone O3 58 particulate pollutants 58 hydrocarbons HC 58 atmospheric pollutants 58 particulate matter emitted 58 CO2 58 pollutant particles 58 fluorocarbons 58 carcinogenic polycyclic aromatic hydrocarbons 57 emmisions 57 cow burps 57 CO -2 57 ozone depleting gases 57 Volatile Organic Compounds 57 greenhouse gases GHGs 57 sulfate aerosols 57 emmissions 57 NOx nitrogen oxide 57 combustion gases 57 particulate emission 57 Sulphur Dioxide 57 Volatile organic compounds 57 Tailpipe emissions 57 methane emitted 57 carbon monoxide nitrogen oxides 57 GHGs 57 Carbon Monoxide CO 57 carbon monoxide particulate matter 57 exhaust emissions 57 NOx 56 polyaromatic hydrocarbons 56 CO ² 56 Nitrogen Oxides 56 VOCs 56 gaseous byproducts 56 CO ₂ 56 hydroxyl radical 56 sulfur oxide SOx 56 particulates 56 pollutant 56 hydrogen sulfide H2S 56 emissions 56 ozone precursors 56 hydrofluorocarbons HFCs perfluorocarbons PFCs 56 methane CH4 56 pollutants 56 emission 56 unburnt fuel 56 NOx emissions 56 nitrogen oxide NOX 56 carbondioxide 56 Volatile Organic Compounds VOCs 55 GHG emitted 55 Nitrogen Oxide 55 gasses 55 pollutant emissions 55 hydroxyl radicals 55 anthropogenic carbon dioxide 55 methane burps 55 Hydrogen Sulphide 55 pollutions 55 combustors 55 tailpipe exhaust 55 methyl chloroform 55 Global Warming Potential GWP 55 nitrogen oxides emitted 55 carcinogenic fumes 55 Sulfur Dioxide SO2 55 reduce NOx emissions 55 Particulate matter 55 greenhouse gases GHG 55 N2O 55 House Gases GHGs 55 aromatic hydrocarbons 55 carbon dioxide 55 particulate matter emissions 55 CO2 emmissions 55 diesel particulate 55 emit sulfur dioxide 55 air pollutants emitted 55 Polycyclic aromatic hydrocarbons 55 sulfur dioxide SO2 emissions 55 carbon dioxide sulfur dioxide 55 hydrocarbons nitrogen oxides 55 noxious gasses 55 ozone particulate matter 54 aerosol particles 54 particulate contaminants 54 #g CO2/km [001] 54 exhaust gasses 54 carbon dioxide CO2 54 carbon dioxides 54 NOx SOx 54 NOx emission 54 chlorinated compounds 54 tropospheric ozone 54 sulfur dioxide particulate matter 54 Particulate pollution 54 nitrous oxide emission 54 emmission 54 Nitrogen oxide emissions 54 petrodiesel 54 Particulate emissions 54 noxious pollutants 54 CO ² emissions 54 terrestrial biosphere 54 pollution 54 tailpipes smokestacks 54 biogases 54 CO2 SO2 54 greenhouse gas nitrous oxide 54 toxic gasses 54 perfluorocarbons PFCs 54 Volatile Organic Compounds VOC 54 volatilized 54 aldehydes 54 dimethyl sulphide 54 global warming gasses 54 unburned hydrocarbons carbon monoxide 54 particulate matter nitrogen oxides 54 siloxanes 54 cow farts 54 gases 54 methane oxidation 54 cow flatulence 54 CO2 emissions 54 methanol formaldehyde 54 NOx nitrogen oxides 54 furans 54 inorganic salts 54 polycyclic aromatic hydrocarbon 53 digestors 53 PM# particles 53 sulfate aerosol 53 Nitrogen Oxide NOx 53 reduces NOx emissions 53 carbon dioxide nitrous oxide 53 sequestering CO2 53 oxidiser 53 CO2 CH4 53 SO3 53 ammonia NH3 53 deplete ozone 53 unburnt hydrocarbons 53 Particulate Matter 53 air pollution 53 cow belches 53 methane 53 CFCs chlorofluorocarbons 53 smog forming pollution 53 sulfur gases 53 fine particulate pollution 53 soot emitted 53 greenhouse gases 53 peroxynitrite 53 vapors emitted 53 harmful gases 53 fatty acid esters 53 hydrofluorocarbon HFC 53 sulfur oxide 53 carcinogenic compounds 53 airborne pollutant 53 exothermic reaction 53 bovine flatulence 53 respirable particulate matter 53 mercury sulfur dioxide 53 particulate matter soot 53 sulphate particles 53 oxidizing agent 53 aerobic decomposition 53 sulfur dioxide pollutant 53 sulfur trioxide 53 obnoxious odors 53 flatulent cows 52 CFCs HCFCs 52 microscopic airborne particles 52 smog forming 52 sulfur hexafluoride SF6 52 heat trapping pollutants 52 Co2 emissions 52 oxidation catalysts 52 particulate matter PM 52 polution 52 Ozone Depleting 52 airborne particulate matter 52 thermal oxidizers 52 bioaerosols 52 nitrification 52 sulfur oxides 52 ozone depleting substance 52 particulate matter 52 particulate soot 52 fluorinated gases 52 nitrogen oxides 52 Ultrafine particles 52 bacterial decomposition 52 fluorinated greenhouse gases 52 airflows 52 refrigerant gases 52 Polybrominated 52 alkanes 52 Carbon Dioxide 52 rumen fermentation 52 condensable 52 diesel particulate emissions 52 carbon dioxide CO ² 52 respirable 52 odorous compounds 52 hydrogen sulfide ammonia 52 nitrogen dioxides 52 sulfate particles 52 biogenic emissions 52 particles emitted 52 Diesel exhaust 52 oxidizers 52 manmade CO2 emissions 52 polycyclic aromatic hydrocarbons PAH 52 catalytically 52 thermal oxidation 52 Exhaust fumes 52 carboxylic acids 52 incomplete combustion 52 methane nitrous oxide 52 exhaust gases 52 nitrogen oxide NOx 52 ozone pollutant 52 hydrogen H2 52 soot particles 52 toxic dioxins 52 enteric fermentation 52 sulfur dioxide SO2 nitrogen 52 monoxide 52 carbon monoxide nitrogen dioxide 52 flue gases 52 nitrogenous compounds 51 sequesters carbon dioxide 51 anaerobic decomposition 51 Lactic acid 51 smokestack scrubbers 51 biogenic 51 sulfuric acid mist 51 perfluorocarbons 51 carbon dioxide emissions 51 sulfuric compounds 51 regenerative thermal oxidizer 51 photosynthetic microorganisms 51 vaporisation 51 fine particulates 51 anaerobes 51 anaerobically digested 51 gases vapors 51 emitted 51 emit carbon monoxide 51 nitrogenous waste 51 nitrogen oxide burners 51 evaporative emissions 51 noxious chemicals 51 ammonia hydrogen sulfide 51 combustible gases 51 Diesel Particulate Filter DPF 51 water vapor 51 Soot particles 51 decomposing manure 51 VOC Volatile Organic Compounds 51 ruminant animals 51 SO2 emissions 51 emit toxic fumes 51 Carbon monoxide CO 51 levulinic acid 51 sulfur hexafluoride 51 sulfur dioxide pollution 51 biomasses 51 Volcanic gases 51 nitrogen oxide pollution 51 CO2 emission 51 volatile organic compounds 51 carbonyl compounds 51 carbon emmissions 51 greenhouse gas 51 airborne particulate 51 trihalomethanes THMs 51 #,# DCB 51 Fine particulates 51 Clogged filters 51 malodour 51 oxidising 51 aftertreatment systems 51 smog forming gases 51 ethoxylates 51 sulfurous gases 51 dioxide emissions 51 VOC volatile 51 chlorofluorocarbons CFC 51 ethanol butanol 51 bioaerosol 51 carbon emissions 51 soluble compounds 51 hydrocarbon vapors 51 nitrous oxides NOx 51 Hydrogen sulphide 51 Emissions 51 olfactory stimuli 51 smoldering coals 51 ethane propane butane 51 particulate contamination 51 NOx oxides 50 anthropogenic emissions 50 SOx NOx 50 dioxides 50 respired 50 VOCs Volatile Organic Compounds 50 C# emissions 50 emit fumes 50 diesel fumes 50 phosphine 50 nitrogen oxide emission 50 leachates 50 oxidized mercury 50 Reactive oxygen species 50 concentration gradient 50 nitrogen monoxide 50 carcinogenic pollutants 50 algal species 50 PAHs polycyclic aromatic hydrocarbons 50 Hydrogen sulfide 50 tiny airborne particles 50 VOC emissions 50 smog forming compounds 50 formaldehydes 50 SCR selective catalytic 50 automobile tailpipes 50 oxidant 50 respirable suspended particulates 50 elemental sulfur 50 bio diesels 50 carbons 50 containing soot dioxins 50 torsional vibrations 50 carbon monoxide nitrogen oxide 50 cyclohexane 50 thermal decomposition 50 hydrochloric acid HCl 50 photochemical smog 50 exhaust fumes 50 carbon disulfide 50 emit pollutants 50 sulfer 50 sulfur oxides nitrogen oxides 50 Sulfur dioxide 50 anthropogenic greenhouse gases 50 stoichiometric 50 nitrogen dioxide carbon monoxide 50 sulfur dioxide SOx 50 smog forming emissions 50 isoprene 50 depolymerization 50 hydrofluorocarbon 50 hydrogen peroxide H#O# 50 allergy inducing 50 greenhouse gas HFC 50 fossile fuels 50 carbonate globules 50 particulate 50 NO2 50 airborne irritants 50 ozone depleting compounds 50 atmospheric aerosols 50 byproduct HFC 50 atmospheric moisture 50 Burning fossil fuels 50 anerobic 50 disagreeable odor 50 smokestack pollutants 50 #yf 50 RenDiesel fuel 50 Halons 50 greenhouses gases 50 Formic acid 50 oxide hydrofluorocarbons perfluorocarbons 50 ethene 50 woodsmoke 50 fluorides 50 chlorine bleaches 50 fluorinated compounds 50 thermochemical processes 50 desulfurization gypsum 50 climate forcings 50 CO2 equivalents 50 photolysis 50 octane enhancer 50 Volatile Organic Compound 50 hydrofluorocarbons HFCs 50 volatilization 50 invisible odorless tasteless 50 acrylamide formation 50 Methane CH4 49 particulate pollution 49 GHG emission reductions 49 oxyhydrogen 49 HFC# 49 Pyrolysis 49 photochemical reactions 49 magnesium silicate 49 emissons 49 formaldehyde benzene 49 carbonyl sulfide 49 cerium oxide nanoparticles 49 exhaust backpressure 49 flatus 49 pollutive 49 Carbon dioxide emitted 49 EtO 49 halocarbons 49 emitting fossil fuels 49 putrescible 49 humidified air 49 nitrogen trifluoride 49 CO2 emitted 49 harmful toxins 49 exhaled carbon dioxide 49 atmospheric CO2 levels 49 endothermic 49 SCR catalytic converter 49 nitric oxides 49 carbon monoxide hydrocarbons 49 microscopic bubbles 49 formamide 49 dioxins furans 49 nitrogen oxides particulate matter 49 dioxide 49 vacuum distillation 49 ozone nitrogen dioxide 49 Sulfur Dioxide 49 exhaust emission 49 silicic acid 49 helium nuclei 49 microbial decomposition 49 phenanthrene 49 Purifier TM 49 mold dust mites 49 sludges 49 emit GHGs 49 fishy odor 49 tailpipe gases 49 SO2 49 allergenic pollen 49 greenhouse gasses emitted 49 forcings 49 electromagnetic radiation EMR 49 mercury emitted 49 sulfur oxides SOx 49 anaerobic oxidation 49 reactive nitrogen 49 chlorinated solvent 49 Odours 49 GHG emissions 49 electromagnetic radiations 49 particulate filter 49 thermal gradients 49 carbon emission 49 Activated carbon 49 anaerobic bacteria 49 methyl chloride 49 bacterial fermentation 49 prussic acid 49 Exhaled 49 Water softeners 49 microbial degradation 49 flue gasses 49 Ionic liquids 49 sulfur dioxide nitrogen dioxide 49 superoxides 49 nitrogen oxide 49 NOx trap 49 Pollutants 49 nitrous oxide NOx 49 Ketones 49 hazardous vapors 49 Ozone O3 49 AdBlue injection 49 singlet oxygen 49 thermally induced 49 chlorofluorocarbon CFC 49 anthropogenic CO2 49 mercaptans 49 toxic pollutant 49 anaerobic environments 49 carbon dioxide nitrogen oxide 49 absorbs carbon dioxide 49 GHG emission 49 airborne pollutants 49 emitting 49 nitrogen oxides NOX 49 phosphoric acids 49 thin stillage 49 Hydrogen Sulfide H2S 49 R#a 49 CFC refrigerants 49 Volatile Organic Compound VOC 49 nicotine vapor 49 gasification pyrolysis 49 Sulfates 49 Particle pollution 49 emittance 49 Nitrous Oxide 49 nitric 49 global warming gases emitted 49 solvent vapors 49 sidestream 49 SO2 emission 49 anthropogenic aerosols 49 chlorofluorocarbon 49 epoxides 48 nitrogen dioxide sulfur dioxide 48 chlorine peroxide 48 Nitrogen Oxides NOx 48 bioaccumulative 48 diesel particulate matter 48 Carbon monoxide byproduct 48 VOC volatile organic 48 Acetaldehyde 48 gasified coal 48 CO2e emissions 48 harmful vapors 48 manmade greenhouse gas 48 carbonic 48 monoterpenes 48 Gaseous 48 respirable particles 48 particulate filters 48 vapor mist 48 gaseous fuels 48 absorption chillers 48 de ionized 48 heterocyclic amines HCAs 48 activated carbons 48 byproducts 48 carbon monoxide colorless odorless 48 stratospheric ozone depletion 48 halon 48 carcinogenic toxins 48 furan 48 odorless vapor 48 photosynthetically 48 Polychlorinated biphenyls PCBs 48 Nitrogen Dioxide 48 HCCI engine 48 electrolyzed 48 PAH concentrations 48 emitting methane 48 superoxide anion 48 Oxidative stress occurs 48 VOC emission 48 outgas 48 hydrogen chloride 48 inert nitrogen 48 nonroad engines 48 alkalis 48 particle filters 48 benzoates 48 oxidisation 48 formaldehyde carcinogen 48 aliphatic hydrocarbons 48 Electromagnetic radiation 48 fumes emanating 48 exothermic 48 nitrogen excretion 48 Selective Catalytic Reduction 48 particulate matter PM#.# 48 atmospheric nitrogen 48 Ozone disinfection produces 48 colorless flammable 48 bile acids 48 organophosphorous 48 corona discharge 48 volatilize 48 sulfur dioxide emission 48 greenhouse gas emissions 48 aerosol propellants 48 emit #g/km 48 flatulence 48 sulpher 48 microbially 48 poisonous hydrogen sulphide 48 carbon dioxide equivalent CO2e 48 Chlorofluorocarbons CFCs 48 dust mites pollen 48 carbon dioxide emission 48 GhG emissions 48 nitrogen NOx emissions 48 oxidizer 48 HCFC #b 48 Ozone depleting 48 polycyclic aromatic 48 VOCs volatile 48 GHGs emitted 48 thermodynamically 48 droplet sizes 48 inorganic minerals 48 ultra violet radiation 48 marketable byproducts 48 renewably 48 bisulfite 48 boiler flue 48 attracting vermin 48 allyl alcohol 48 acetaldehyde 48 polycyclic aromatic hydrocarbons PAHs 48 sugars starches 48 flammable solvents 48 halogenated hydrocarbons 48 Sodium cyanide 48 cellulose hemicellulose 48 cavitations 48 estrogenic chemicals 48 HAAs 48 Carbon Dioxide CO2 emissions 48 thermochemical processing 48 aqueous urea solution 48 microemboli 48 Lengai 48 aromatic compounds 48 nitrogen oxides sulfur oxides 48 GHG concentrations 48 poisonous gasses 48 boron trifluoride 48 allergenic proteins 48 hydrochlorofluorocarbon 48 vapor 48 harmful pollutants 48 HFC refrigerants 48 microbials 48 photosynthetic machinery 48 refrigerant leakage 48 diesel particulate filter DPF 48 bacterias 48 farting cows 48 respirable suspended 48 sulfur diesel fuel 48 tributyltin TBT 48 unpleasant odors 48 Mercaptan 48 hepatic glucose production 48 ultrafine particles 48 cow enteric 48 hydrogen chloride HCl 48 acid alkali 48 compound VOC 48 noble gases 48 methanogenic bacteria 48 GHG 48 humic acids 48 absorbs CO2 48 osmotic pressure 48 toxic hydrogen sulfide 48 odor neutralizer 48 offgas 48 cavitation 48 Excess nitrogen 47 gasified 47 halogenated 47 spoilage bacteria 47 Electrostatic precipitators 47 carbon tetrachloride 47 nauseating odor 47 synthetic nitrogen fertilizer 47 Chlorine bleach 47 inorganic fertilizers 47 botanical insecticide 47 effluents 47 CO2emissions 47 EGR cooler 47 lignocellulose 47 aerosols 47 dissolved salts 47 photoionization 47 harmless nitrogen 47 oxidise 47 #,# butadiene 47 linoleic acids 47 isotope fractionation 47 unpleasant smells 47 Diesel fumes 47 conventional combustion engines 47 thiourea 47 Ozone depletion 47 halogenated compounds 47 ghg emissions 47 sulfur compounds 47 Hydrazine 47 gypsum byproduct 47 nitrates phosphates 47 sulfur dioxide 47 degreasing agent 47 Elemental mercury 47 airborne particulates 47 carbon sequestered 47 harmful contaminants 47 gasifying coal 47 oxidants 47 nonrenewable fossil fuels 47 coarse particles 47 EGR Exhaust Gas Recirculation 47 benzene toluene 47 Enviro Log firelogs 47 Nitric acid 47 nitrification inhibitors 47 sulphates 47 spontaneously ignite 47 Carbon dioxide emissions 47 trans palmitoleate 47 microbial enzymes 47 aerosol spray cans 47 Nitrogen NOx 47 CO ₂ emissions 47 hazardous solvents 47 sulfur fumes 47 emis sions 47 insufflation 47 carbon emitted 47 noxious vapors 47 coproduct 47 aggravates asthma 47 chrysotile fibers 47 pentaBDE 47 thermal hydrolysis 47 dissolver 47 waste decomposes 47 emits #g/km [001] 47 hydrogen sulphide 47 nanoclays 47 coagulation proteins 47 cetane 47 rumen bacteria 47 carbon dioxide methane 47 crop residues 47 benzenes 47 neuro toxin 47 Breathing ozone 47 H#O# 47 carcinogenic chemicals 47 Endocrine disruptors 47 Hydrochloric 47 GDi 47 ketone bodies 47 carbonic acid 47 aromatic amines 47 lung irritant 47 particulate traps 47 Sugarcane ethanol 47 bio degradable waste 47 methane ethane 47 evaporative 47 crystalline silica dust 47 trichloroethane 47 carbon dioxide emitted 47 diesel particulate filter 47 cyanogen 47 Cow burps 47 inorganic ions 47 autotrophic 47 nitrous acid 47 carbon dioxide emission reductions 47 trapping gases 47 Prussic acid 47 VOCs volatile organic compounds 47 H2S 47 sulfur gasses 47 volcanic aerosols 47 combustor 47 pyrene 47 nitric acids 47 bio accumulative 47 nitrate nitrite 47 Nitrogen trifluoride 47 chlorine atoms 47 removes impurities 47 frequency harmonics 47 pelletization 47 ionise 47 emit CO2 47 calorific values 47 methyl hydrate 47 Haber Bosch process 47 Adequate ventilation 47 C#H# 47 thermogenesis 47 PCBs dioxins 47 carcinogenic byproducts 47 Karen Schkolnick spokeswoman 47 fecal pellets 47 carbonization 47 thiocyanate 47 HCCI mode 47 carbon 47 TSNA 47 contrast chlorine disinfection 47 pesticides herbicides fertilizers 47 ATP hydrolysis 47 Co2 emission 47 methylamine 47 nitrogen oxides NO 47 carcinogenic substances 47 VOC abatement 47 Air fresheners 47 Underinflated tires 47 nuclides 47 n butanol 47 diesel particulate filters DPF 47 Emitting 47 halons 47 Plasma gasification 47 sonication 47 degumming 47 pyrophoric 47 putrid odors 47 toxic alkaloids 47 soluble carbohydrates 47 seawater pH 47 toxaphene 47 demineralized water 47 heme iron 47 HumiFilters 47 forest thinnings 47 irritate lungs 47 CO2/km 47 gassification 47 detergents solvents 47 PM#s 47 carcinogenic dioxins 47 fluid shear 47 metallic salts 47 smog forming chemicals 47 nitrous oxide NOx emissions 47 washwater 47 repel pests 47 pentane 47 Diesel Particulate Filters 46 nitrogen NOx 46 viscosity liquids 46 Kharecha 46 nitrate fertilizers 46 tailpipe emission 46 carbon monoxide sulfur dioxide 46 microwave popcorn bags 46 sulphite 46 airborne particles 46 acid hydrolysis 46 swim bladders 46 ethanols 46 preg robbing 46 composite airframes 46 #g/km CO2 [002] 46 biowaste 46 shredder residue 46 microbial organisms 46 Hydrogen Sulfide 46 oxidized cholesterol 46 SF6 46 TiO2 nanoparticles 46 ODSs 46 toxicants 46 methyl ethyl 46 exhale carbon dioxide 46 reactant 46 nitrite nitrate 46 ionize 46 equimolar 46 CO2 eq 46 ozone layer depletion 46 anthropogenically 46 fat globules 46 sugar cane bagasse 46 noxious gases 46 Nitric oxide NO 46 produced Friedlingstein 46 DPFs 46 charcoal canister 46 biodegradable recyclable 46 atmospheric deposition 46 colorless odorless poisonous 46 cow rumen 46 fluorinated chemicals 46 biosequestration 46 centrifugal blower 46 methanogenesis 46 autoclaving 46 hydroxyl ions 46 chemically reactive 46 Boric acid 46 metabolic byproducts 46 Chlorine dioxide 46 ruminant livestock 46 Golf Bluemotion 46 Nitrosamines 46 toxic pollutants 46 heterogeneous catalysts 46 ultraviolet sunlight 46 sidestream smoke 46 Asbestos fibers 46 soluble salts 46 soot 46 heterocyclic amines 46 infrared photons 46 respiratory irritant 46 electromagnetic frequencies 46 dewpoint temperature 46 fungal toxins 46 halogenated gases 46 sulfur dioxide SO 46 electrochemical oxidation 46 hydroxide ions 46 Diesel Particulate Filter 46 paints sealants 46 ozone particulates 46 liquid oxygen LOX 46 electromagnetic flux 46 fluidized 46 flux residues 46 absorption spectra 46 Benzo pyrene 46 thermoelectric cooling 46 Demand BOD 46 respiring 46 Limonene 46 uric acids 46 biofiltration 46 microcystins 46 animal manures 46 acidifies 46 mercury Hg 46 pollen spores 46 vaporiser 46 NOX SOX 46 feebates 46 iso octane 46 Bio SPK 46 diesel exhaust 46 radioactive iodide 46 enzymatic hydrolysis 46 urea injection 46 pollen mold spores 46 harmful dioxins 46 cellulases 46 barium chloride 46 benzopyrene 46 toxins 46 interparticle 46 airway constriction