Related by context. All words. (Click for frequent words.) 59 organochlorine 59 toxaphene 58 endrin 58 Chlordane 58 organochlorines 57 organophosphate insecticides 56 pfiesteria 56 DDT PCBs 56 Polychlorinated biphenyls 56 PCBs dioxins 56 chlordane 56 chlordecone 56 Chromium VI 55 endocrine disrupters 55 endocrine disrupting chemical 55 benzene arsenic 55 Methyl mercury 55 heptachlor 55 synthetic musks 55 naturally occurring bacterium 55 estrogen mimicking 55 Anabaena 55 estrogenic compounds 55 piperonyl butoxide 54 mirex 54 polychlorinated biphenyl 54 trichloroethene TCE 54 dioxins PCBs 54 tetrachloroethene 54 aldrin 54 estrogenic chemicals 54 PCBs polychlorinated biphenyls 54 diphacinone 54 organo phosphate 54 toxicants 54 naturally occurring toxin 54 hormone disrupter 54 cancer causer 53 Dieldrin 53 dieldrin 53 PCBs dioxin 53 toxicant 53 mimics estrogen 53 polynuclear aromatic hydrocarbons 53 Paraquat 53 tributyltin TBT 53 e coli bacteria 53 toxicosis 53 endocrine disrupter 53 Microcystis 53 pesticides chlorpyrifos 53 sumithrin 53 amphibole asbestos 53 Pyrethroids 53 microcystins 53 benzo pyrene 53 dioxin PCBs 52 banned pesticide DDT 52 Endocrine disruptors 52 trichloroethane 52 PAHs polycyclic aromatic hydrocarbons 52 PCBs DDT 52 diphenyl ethers 52 Carcinogen 52 endocrine disrupting chemicals 52 Prenatal exposure 52 carbamate insecticides 52 tetrachlorethylene PCE 52 polychlorinated biphenyl PCB 52 chlorinated hydrocarbon 52 triclocarban 52 algal toxins 52 organochlorine pesticides 52 nonylphenol 52 potent carcinogen 52 endocrine disruptors 52 vinclozolin 52 suspected carcinogen 52 carcinogenic dioxins 52 endocrine disrupting 52 THMs 51 Methomyl 51 Organophosphate 51 sodium hydrochloride 51 polyaromatic hydrocarbons 51 solvents pesticides 51 simazine 51 Carbofuran 51 perfluorinated chemicals 51 TCE trichlorethylene 51 Lyngbya 51 organophosphorus 51 hormone disrupters 51 organophosphate pesticide 51 formaldehyde benzene 51 biphenyls PCBs 51 Methylmercury 51 organophosphate 51 Polychlorinated Biphenyls 51 Water hyacinth 51 PCBs pesticides 51 bacterium Clostridium 51 neonicotinoid 51 endocrine disruptor 51 genotoxic substance 51 microcystis 51 hexachlorobenzene 51 herbicide Atrazine 51 Malachite green 51 Carbaryl 50 sublethal 50 mercury dioxins 50 dioxins furans 50 Acrolein 50 bioaccumulation 50 azinphos methyl 50 cyanide arsenic 50 Ciguatera 50 Caulerpa 50 pesticides herbicides fungicides 50 brodifacoum 50 eggshell thinning 50 pentachlorophenol 50 chemical C8 50 Hydrogen cyanide 50 Organophosphates 50 nitrates phosphates 50 Shiranui Sea 50 polybrominated diphenyl ether 50 e.coli bacteria 50 PBDEs polybrominated diphenyl ethers 50 flame retardants PBDEs 50 diazinon 50 Vinyl chloride 50 organophosphorus pesticides 50 chlorinated hydrocarbons 50 fungus Aspergillus 50 perfluorooctanoic acid PFOA 50 reproductive abnormalities 50 Chlorpyrifos 50 bioaccumulative 49 chlorinated compounds 49 endocrine disruption 49 unlined ponds 49 arsenic selenium 49 Contaminant 49 chemicals 49 Inert ingredients 49 Palos Verdes Shelf 49 Polychlorinated biphenyls PCBs 49 biphenyls 49 polychlorinated PCBs 49 Pseudo nitzschia 49 Nitrosamines 49 contaminant 49 CheckMate LBAM F 49 organochlorine pesticide 49 synthetic pyrethroids 49 2 butoxyethanol 49 Squalene 49 carcinogenic chemicals 49 pyrethroids 49 hormone mimicking 49 aromatic amines 49 endocrine disrupting chemicals EDCs 49 stachybotrys 49 cadmium arsenic 49 ethyl mesilate 49 naturally occurring fungus 49 parathion 49 hormone disruptor 49 hydrogen cyanide HCN 49 scorpion toxin 49 contain tetrodotoxin 49 toxin 49 Dichloro Diphenyl Trichloroethane DDT 49 brevetoxin 49 organophosphate OP 49 ethyl acrylate 49 cyromazine 49 phthalate esters 49 Sulphur dioxide 49 hormone disrupting 49 DDT dieldrin 49 pesticides flame retardants 49 DuPont DeLisle plant 49 aquatic toxicologist 49 mutagens 49 Carcinogenic 49 pyrethrins 49 perfluorinated compounds 48 Sodium cyanide 48 Sodium Hydroxide 48 insecticide malathion 48 Hexavalent chromium 48 Acrylamide 48 carbon tetrachloride 48 drywall emits 48 toxins 48 enteric bacteria 48 Nitrate contamination 48 pesticides 48 propyl mercaptan 48 Chlorinated 48 Lindane 48 PCBs mercury 48 potent neurotoxin 48 ethyl benzene 48 Benzyl 48 contaminants 48 PFCAs 48 dioxin laced 48 Cladosporium 48 carcinogenic substance 48 fecal chloroform 48 Fecal coliform bacteria 48 solvent toluene 48 clostridium botulinum 48 DDT pesticide 48 Insecticidal 48 chlorinated pesticides 48 antimycin 48 antibiotic chloramphenicol 48 algal species 48 Tittabawassee River floodplain 48 algal toxin 48 maneb 48 chemical defoliant Agent Orange 48 Parthenium 48 polybrominated 48 DDVP 48 Chinese mitten crabs 48 contaminate shellfish 48 Rhodamine B 48 organophosphate insecticide 48 organophosphorous 48 neurotoxin 48 Malathion 48 Jimson weed 48 degreasing solvent 48 roxarsone 48 Dursban 48 pesticide contamination 48 Avitrol 48 carbamate 48 Pyrethrins 48 hormone disruptors 48 intersex fish 47 aerially sprayed 47 pesticides aldrin 47 ecotoxicology 47 insecticidal properties 47 powerful neurotoxin 47 perfluorooctane sulfonate PFOS 47 chlorinated solvents 47 PAH compounds 47 naturally occurring algae 47 brevetoxins 47 toxin microcystin 47 Inorganic arsenic 47 dichloroethene 47 Corrosive 47 Amyl 47 polychlorinated biphenyls PCBs 47 E. Coli bacteria 47 Tetrachloroethylene 47 fungal toxins 47 arsenic cyanide 47 Polybrominated 47 trichloroethene 47 acute toxicity 47 ecotoxicologist 47 #,#,# trichloroethane 47 fungus Batrachochytrium dendrobatidis 47 alachlor 47 tebuthiuron 47 PDBEs 47 prenatal exposures 47 plastics detergents 47 phosphates nitrates 47 colorless flammable 47 chlortetracycline 47 pesticide aldicarb 47 organochlorine compounds 47 inorganic mercury 47 chemical malachite green 47 dichlorobenzene 47 methomyl 47 Prussic acid 47 oestrogens 47 Triclosan 47 glycol ethers 47 waterborne pathogens 47 sodium lauryl sulphate 47 Eurasian Milfoil 47 C. ariakensis 47 Trichloroethylene TCE 47 Batrachochytrium dendrobatidis 47 carcinogen dioxin 47 algaes 47 pollen ragweed 47 parasites fungi 47 mold fungi 47 decaying algae 47 tetrachloroethene PCE 47 potent carcinogens 47 n butyl 47 Residues 47 Halogenated 47 organophosphates 47 alkylphenols 47 chemical 47 aromatic amine 47 ammonium chloride 47 pyrethroid pesticides 47 nitrate contamination 47 arsenic chromium 46 spore forming bacteria 46 diuron 46 pathogenic micro organisms 46 Pfiesteria 46 beryllium dust 46 biphenyl 46 Excess nitrogen 46 Stachybotrys 46 Trichloroethylene 46 arsenic cadmium copper 46 C. parvum 46 Acetaldehyde 46 benzene toluene xylene 46 household detergents 46 dichlorodiphenyltrichloroethane 46 Serratia marcescens 46 Polybrominated diphenyl ethers PBDEs 46 phosphine gas 46 carcinogens mutagens 46 dioxin TCDD 46 weevil infestation 46 invasive zebra mussels 46 Vesivirus 46 potent toxin 46 persistent bio accumulative 46 trichlorethylene TCE 46 lindane 46 ammonium nitrogen 46 Ecoli 46 aflatoxins 46 another Parkinson's triggering 46 coli bacteria 46 volatilized 46 chartarum 46 barium chloride 46 organotins 46 cone snails 46 Groundwater contamination 46 contaminating waterways 46 dimethyl sulfide 46 Nitric acid 46 neurotoxins 46 Mytilus 46 disinfection byproducts 46 Dioxane 46 pesticide atrazine 46 bacterium Bordetella pertussis 46 furan 46 Rotenone 46 Pesticides 46 metolachlor 46 hormonally active 46 pseudomonas 46 dimethoate 46 hypoglycin 46 deltamethrin 46 poly aromatic hydrocarbons 46 bioaccumulates 46 p DDE 46 phytoplasma 46 spider venom 46 Hypochlorite 46 azo dyes 46 herbicide atrazine 46 Formalin 46 methyl mercury 46 #,# dichloroethane 46 K. brevis 46 respiratory tract irritation 46 toxicity 46 toxins leaching 46 Contaminants 46 jimson weed 46 Clostridium Botulinum 46 arsenic 46 nerve toxin 46 Cryptococcus neoformans 46 Anopheles stephensi 46 acaricide 46 industrial solvent trichlorethylene 46 citri 46 nitrate nitrogen 46 imazapyr 46 chemical fertilizers herbicides 46 Chloramines 46 chlorpyrifos 46 vaccine preservative thimerosal 46 Seveso Italy 46 butanone 46 toxins secreted 46 haloacetic acids 46 chemical perfluorooctanoic acid 46 pesticide 46 polycyclic aromatic hydrocarbon 46 Propyl mercaptan 46 PFOAs 46 benzyl 46 Cry1Ab 46 cyanobacteria blooms 46 Atrazine 46 myrtle rust 46 tributyl tin 46 toxic 46 Rynaxypyr TM 46 pungent smelling 46 carbaryl 46 cladophora 46 fluorides 45 hexavalent 45 phosphorus pollution 45 sulfated chondroitin sulfate 45 monocytogenes 45 Airplanes sprayed 45 Cladophora 45 radiological contaminants 45 naturally occurring bacteria 45 malachite green 45 ramorum 45 arsenic benzene 45 Athabasca watershed 45 Limonene 45 endocrine disrupting compounds 45 cyanogenic glycosides 45 Nitrate 45 E Coli bacteria 45 Enterococci 45 coal tars 45 protozoan parasite 45 phyto oestrogens 45 Dechlorane Plus 45 diquat 45 fecal coliform contamination 45 Erwinia 45 Dimension Data plc LSE 45 methyl parathion 45 bacterium Bacillus thuringiensis 45 inorganic contaminants 45 juglone 45 toxic algal bloom 45 microcystin 45 insect repellent DEET 45 #,# Dioxane 45 para dichlorobenzene 45 dioxin 45 Mercaptan 45 toxicologist 45 disinfection byproducts DBPs 45 vibrio parahaemolyticus bacteria 45 gypsy moth larvae 45 microbial degradation 45 cypermethrin 45 enterococcus bacteria 45 pyrethroid 45 polychlorinated 45 Zebra Mussel 45 chlorinated solvent 45 leopard frog tadpoles 45 Toxic 45 hydrogen sulfide gases 45 gambiae 45 paradichlorobenzene 45 diethyl 45 dioxides 45 Candidatus 45 Polycyclic Aromatic Hydrocarbons 45 BMSB 45 Mycotoxins 45 perfluorochemicals 45 superantigen 45 aquatic biota 45 tobacco budworm 45 PAH concentrations 45 perfluorooctane sulfonate 45 Domoic acid neurotoxin 45 toxic polychlorinated biphenyls 45 microscopic parasites 45 Sumithrin 45 microbial pathogens 45 ciguatera 45 aspergillus 45 nitrates nitrites 45 gentian violet 45 sulfur trioxide 45 green alga 45 groundwater contaminant 45 Dimilin 45 organochlorine insecticide 45 Penicillium 45 mercury chromium 45 toxic dioxins 45 organophosphate pesticides 45 Toxin 45 pyrethroid insecticide 45 #,#,# trichloroanisole 45 hatchery raceways 45 dioxins 45 pesticide malathion 45 chlorobenzene 45 formaldehyde resin 45 fungicides herbicides 45 C. botulinum 45 naturally occuring 45 dioxane 45 C. perfringens 45 E coli bacteria 45 malathion 45 Diacetyl 45 chromium mercury 45 bacillus cereus 45 Hydrogen sulfide 45 benzene formaldehyde 45 neonicotinoids 45 stalk borer 45 spore forming bacterium 45 benzoates 45 EDCs 45 Algae bloom 45 hydrocyanic acid 45 cleaners disinfectants 45 acid sulphate 45 Fecal Coliform 45 carcinogenic PCBs 45 Sulfates 45 cyanogenic 45 polybrominated diphenyl ethers PBDEs 45 aminopterin rat poison 45 deadly nightshade 45 clostridium 45 Domoic acid 45 nitric acids 45 bacteria listeria monocytogenes 45 cyclamates 45 methyl tert butyl ether 45 pesticides fungicides 45 fluridone 45 anthrax Bacillus anthracis 45 fecal indicator 45 mercury PCBs 45 Varroa mites 45 synthetic estrogen 45 dichloroethane 45 amphibian chytrid fungus 45 pediatric toxicologist 45 B. cepacia 45 chemical diethylene glycol 45 engineers AIChE SmartBrief 45 contaminents 45 Hydrochloric 44 reproductive toxins 44 wastewater effluent 44 dichloroethylene 44 polyphenyl isocyanate 44 human carcinogen 44 sulfur gases 44 polycyclic aromatic hydrocarbons PAHs 44 Dr Landos 44 salmonella listeria 44 Phenol 44 vibrio bacteria 44 coli salmonella 44 mercury contamination 44 sea lampreys 44 developmental neurotoxicity 44 Dibrom 44 nontarget species 44 farms atrazine metolachlor 44 TTHMs 44 aromatic hydrocarbons 44 Diethyl 44 carcinogenic byproducts 44 Bt# corn 44 Aspergillus flavus 44 cyanazine 44 bio accumulative 44 polychlorinated vinyls 44 cyst nematode 44 Imidacloprid 44 tributyltin 44 thimerosal mercury containing 44 soils sediments 44 Aeromonas 44 Ingestion 44 Fipronil 44 furans 44 herbicide residues 44 PCBs 44 Coliform 44 toxic pollutant 44 ethylene dibromide 44 synthetic estrogens 44 carcinogenic polycyclic aromatic hydrocarbons 44 pentachlorophenol PCP 44 bacteria Clostridium botulinum 44 pyrene 44 synthetic stimulant 44 perchlorethylene toxic 44 bifenthrin 44 sodium bisulfate 44 Salicylate 44 prussic acid 44 Cotinine 44 neuro toxin 44 Phosphoric acid 44 Toxicity 44 fragrances dyes 44 rat poisons 44 Sewage sludge 44 carcinogenic pollutants 44 chitinase 44 monocrotophos 44 PFBA 44 odorless tasteless 44 arsenic cadmium chromium 44 Cryptosporidium parasite 44 toxic chemicals 44 Intersex fish 44 Foray #B 44 Household cleaners 44 Escherichia Coli 44 insecticide chlorpyrifos 44 bacteria fungi viruses 44 microbial biofilms 44 bacterium Pseudomonas aeruginosa 44 Hexane 44 protozoan parasites 44 DBPs 44 PBDE flame retardants 44 Neurotoxicity 44 Clostridium perfringens 44 trihalomethanes THMs 44 organochlorine insecticides 44 Glyphosate resistant 44 staphylococcus bacteria 44 toxic algae blooms 44 P. ramorum 44 endophyte 44 harmful algae blooms 44 benzopyrene 44 inorganic salts 44 carcinogenic benzene 44 hydrogen sulphide H2S 44 pollutants 44 vom Saal 44 fumonisins 44 oomycetes 44 aquatic toxicity 44 Phragmites 44 ecotoxicological 44 environmental toxicants 44 toxoplasma gondii 44 Enterococcus 44 Foliar 44 defoliants 44 microbiological organisms 44 reproductive toxicants 44 Bacillus cereus 44 pesticide chlorpyrifos 44 Polysorbate 44 shigella bacteria 44 rBGH milk 44 chromic acid 44 Phosgene 44 algal bloom 44 mimic estrogen 44 Calicivirus 44 metabolize dispersant 44 Codling moth 44 Stachybotrys chartarum 44 Spinosad 44 insecticides fungicides 44 ethinylestradiol 44 naphthalene 44 Toxoplasmosis 44 Fecal contamination 44 Insect Control 44 salvinia 44 domoic acid naturally occurring 44 Serum phosphorus 44 Aldicarb 44 contamination 44 Tetrodotoxin 44 Dehalococcoides 44 Dioxin 44 Aflatoxin corn 44 benzenes 44 budworm 44 Didymo 44 Toxicologists 44 TCE PCE 44 viral bacterial 44 coumarin 44 carcinogenic 44 hydrochloric acid HCl 44 Estrogenic 44 Aflatoxins 44 Sodium hydroxide 44 Septoria leaf spot 44 allergens irritants 44 arsenic contaminated 44 hydrogen chloride HCl 44 aflatoxin B1 44 artificial sweetener saccharin 44 Fumigants 44 duckweed 44 fusarium fungus 44 rodent poisons 44 potentially carcinogenic 44 degreasing agent 44 nitrofuran 44 E.Coli bacteria 44 perfluorochemicals PFCs 44 allelopathic 44 Sodium Chloride 44 pyrethroid insecticides 44 HBCD 44 Pseudomonas aeruginosa bacteria 43 Scott Mabury 43 Klebsiella bacteria 43 fecal material 43 Toxins 43 benzene xylene 43 Campylobacter bacteria 43 spore forming 43 eucalyptol 43 radioactive thorium 43 biogenic amines occur 43 anticarcinogenic 43 Chemical Hazards 43 toxigenic 43 anti androgenic 43 honeybees bumblebees 43 Chloramine 43 pesticides herbicides fertilizers 43 metal degreasing 43 insecticides pesticides 43 excitotoxins 43 fumonisin 43 molds fungi 43 nootkatone 43 Bacillus thuringiensis var 43 putrid odors 43 polycyclic aromatic hydrocarbons PAH 43 nauseating odors 43 lampricide 43 bacterial decomposition 43 atrazine herbicide 43 occupationally exposed 43 bacillus thuringiensis 43 E. Coli O# H7 43 cyanides 43 thirdhand smoke 43 jimsonweed 43 trihalomethane 43 chemical perfluorooctanoic acid PFOA 43 pseudomonas aeruginosa 43 kills mosquito larvae 43 fungicides insecticides 43 stain repellents 43 veterinary epidemiologist 43 synthetic pyrethroid 43 Perfluorinated chemicals 43 dichlorodiphenyltrichloroethane DDT 43 anthrax ricin 43 Pesticide residues 43 Environmental Toxicology 43 sicken humans 43 clopyralid 43 cadmium chromium 43 Gwen Gilson 43 tetrahydrofuran 43 Tussock Moth 43 glucoside 43 Shigella bacteria 43 leaking septic tanks 43 Deleterious 43 dust mites pollen 43 reproductive toxicity 43 Fecal coliform 43 DecaBDE 43 amyl nitrite 43 Duckweed 43 Sulforaphane 43 sodium hydrosulfite 43 PBDE contamination 43 Smeyne 43 benzene ethylbenzene 43 Cancer Causing 43 acuminata 43 phytoplankton zooplankton 43 metam sodium 43 Mycotoxin 43 microbiological contaminants 43 cyanobacterial toxins 43 cadmium poisoning 43 Clostridium bacteria 43 naturally occurring toxins 43 deicing fluids propylene glycol 43 bacterium Pseudomonas 43 Escherichia coli bacteria 43 weed infestation 43 toxic cyanobacteria 43 carcinogen 43 Ingested 43 Lewisite 43 smooth cordgrass 43 teratogens 43 Cryptococcus gattii 43 polybrominated diphenyl ether PBDE 43 Cryptosporidium parvum 43 toxic algae 43 barium arsenic 43 calcium hypochlorite 43 hydrocarbon vapors 43 glyphosate resistant weed 43 avian botulism 43 contrast chlorine disinfection 43 Bilharzia 43 parasite Cryptosporidium 43 Pollutants 43 sensitizers 43 degrease parts 43 3 methylbenzamide 43 Bruce Lanphear 43 nitrofurans 43 Bromate 43 spider mite 43 nonylphenol ethoxylates 43 Pesticide 43 Turbidity 43 methylparaben 43 ammonium perfluorooctanoate 43 Dimension Data LSE 43 naturally occurring 43 herbicide paraquat 43 pollutant 43 accidentally ingesting 43 xenoestrogens 43 allergenic reactions 43 carcinogenic toxins 43 barium cadmium 43 milky latex 43 Aflatoxin 43 acrylamides 43 aluminum phosphide 43 heterotrophic bacteria 43 elevated atmospheric CO2 43 HAAs 43 toxic byproducts 43 Brackish water 43 anthrax bacillus 43 THC tetrahydrocannabinol 43 arsenic barium 43 trigger allergic reactions 43 Pyrethrin 43 contaminate groundwater 43 atmospheric deposition 43 bleach ammonia 43 #,# dichlorobenzene 43 respiratory irritant 43 quaternary ammonium compounds 43 protozoans 43 Melioidosis 43 Contamination 43 hexachlorobenzene HCB 43 Xylene 43 contain aflatoxin 43 herbicide sprays 43 Jernejcic 43 cottonmouth snake 43 Arsenic 43 insecticides herbicides fungicides 43 kanamycin 43 allyl alcohol 43 creatures slithered 43 Bioremediation 43 dental amalgams 43 Bite Blocker 43 cyanidin 43 nitrogenous compounds 43 unpermitted discharge 43 BSE prions 43 terpenoids 43 terpenes 43 pea aphids 43 Chlorine bleach 43 PCB contamination 43 carcinogenic substances 43 polybrominated biphenyls 43 canthaxanthin 43 pyrethroid resistant 43 neurotoxic 43 acrolein 43 Sterols 43 calcium hydroxide 43 flammable corrosive 43 e coli contamination 43 zearalenone 43 pthalates 42 bactericide 42 Pathogenic 42 Methyl 42 Aspergillus niger 42 psoralen 42 benzyl alcohol 42 mercury arsenic 42 Ivon Watkins Dow 42 tetrachlorethylene 42 biotoxin 42 sunlight ultraviolet rays 42 Dimethyl 42 Legionella pneumophila 42 bacteria mold mildew 42 dioxin contaminated 42 oleuropein 42 inhaling vapors 42 poison sumac 42 cone snail 42 monensin 42 systemic insecticides 42 Contaminates 42 mercury concentrations 42 diacetyl vapors 42 carbamates 42 Disease Registry ATSDR 42 methyl naphthalene 42 biomagnification 42 sulfated 42 selenium concentrations 42 methylene chloride 42 opportunistic pathogens 42 Soy isoflavones 42 phosphorous nitrogen 42 insecticides herbicides 42 DDT 42 carcinogenic compounds 42 contaminants leach 42 Glycerol 42 degreasing solvents 42 Muriatic acid 42 root weevil 42 polluting groundwater 42 butyl acetate 42 aminopyralid 42 ethylmercury 42 vinyl chloride 42 Thimerosal mercury 42 Polybrominated diphenyl ethers 42 fipronil 42 Nitrates 42 bacteria Bacillus 42 paints solvents pesticides 42 bactericides 42 Hydrochloric acid 42 organotin 42 pollen dust mites 42 Bonide 42 botulism spores 42 Brominated 42 carcinogenic chemical 42 Flame retardants 42 Toxic chemicals 42 phosphorus runoff 42 Carbon tetrachloride 42 frog deformities 42 Noxious 42 bromine compounds 42 methyl ethyl ketone 42 thiourea 42 V. parahaemolyticus 42 ecotoxicity 42 neurotoxic effects 42 crystalline silica 42 insecticide DDT 42 Nicknamed andro 42 lambda cyhalothrin 42 parthenium 42 Algal 42 mercuric 42 acid PFOA 42 Escherichia coli E. coli 42 Benzo pyrene 42 haloacetic acid