### A GENCY FOR 

### T OXIC 

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### D ISEASE 

### R EGI STRY 

### 2011 PRIORITY LIST O F HAZARDOUS SUBSTANC ES

1 2011 Rank Substance Name Total Points 2007

Rank CAS # 1 ARSENIC 1665.5 1 007440 - 38 - 2 2 LEAD 1529.1 2 007439 - 92 - 1 3 MERCURY 1460.9 3 007439 - 97 - 6 4 VINYL CHLORIDE 1361.1 4 000075 - 01 - 4 5 POLYCHLORINATED BIPHENYLS 1344.1 5 001336 - 36 - 3 6 BENZENE 1332.0 6 000071 - 43 - 2 7 CADMIUM 1318.7 7 007440 - 43 - 9 8 BENZO(A)PYRENE 1305.7 9 000050 - 32 - 8 9 POLYCYCLIC AROMATIC HYDROCARBONS 1282.3 8 130498 - 29 - 2 10 BENZO(B)FLUORANTHENE 1252.4 10 000205 - 99 - 2 11 CHLOROFORM 1207.5 11 000067 - 66 - 3 12 AROCLOR 1260 1190.0 14 01109 6 - 82 - 5 13 DDT, P,P' - 1183.0 12 000050 - 29 - 3 14 AROCLOR 1254 1171.7 13 011097 - 69 - 1 15 DIBENZO(A,H)ANTHRACENE 1155.2 15 000053 - 70 - 3 16 TRICHLOROETHYLENE 1151.1 16 000079 - 01 - 6 17 CHROMIUM, HEXAVALENT 1146.6 18 018540 - 29 - 9 18 DIELDRIN 1143.1 17 000060 - 57 - 1 19 PHOSPHORUS, WHITE 1141.9 19 007723 - 14 - 0 20 HEXACHLOROBUTADIENE 1128.5 22 000087 - 68 - 3 21 DDE, P,P' - 1127.2 21 000072 - 55 - 9 22 CHLORDANE 1126.4 20 000057 - 74 - 9 23 COAL TAR CREOSOTE 1124.8 23 008001 - 58 - 9 24 AROCLOR 1242 1123.8 29 053469 - 21 - 9 25 ALDR IN 1115.8 24 000309 - 00 - 2 26 DDD, P,P' - 1114.2 25 000072 - 54 - 8 27 AROCLOR 1248 1103.9 27 012672 - 29 - 6 28 HEPTACHLOR 1101.1 34 000076 - 44 - 8 29 AROCLOR 1099.4 30 012767 - 79 - 2 30 BENZIDINE 1090.6 26 000092 - 87 - 5 31 ACROLEIN 1088.5 37 000107 - 02 - 8 32 TOXAPHENE 1087.7 31 008001 - 35 - 2 33 TETRACHLOROETHYLENE 1077.4 33 000127 - 18 - 4 34 HEXACHLOROCYCLOHEXANE, GAMMA - 1074.7 32 000058 - 89 - 9 35 CYANIDE 1071.9 28 000057 - 12 - 5 36 HEXACHLOROCYCLOHEXANE, BETA - 1053.5 36 000319 - 85 - 7 37 BENZO(A)ANTHRACENE 1047.6 39 000056 - 55 - 3 38 DISULFOTON 1047.2 38 000298 - 04 - 4 39 1,2 - DIBROMOETHANE 1041.9 35 000106 - 93 - 4 40 ENDRIN 1038.3 41 000072 - 20 - 8 41 DIAZINON 1036.7 56 000333 - 41 - 5

### A GENCY FOR 

### T OXIC 

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### D ISEASE 

### R EGI STRY 

### 2011 PRIORITY LIST O F HAZARDOUS SUBSTANC ES

2 2011 Rank Substance Name Total Points 2007

Rank CAS # 42 HEXACHLOROCYCLOHEXANE, DELTA - 1034.8 43 000319 - 86 - 8 43 BERYLLIUM 1032.7 42 007440 - 41 - 7 44 ENDOSULF AN 1028.0 54 000115 - 29 - 7 45 AROCLOR 1221 1027.1 48 011104 - 28 - 2 46 1,2 - DIBROMO - 3 - CHLOROPROPANE 1025.8 44 000096 - 12 - 8 47 HEPTACHLOR EPOXIDE 1021.4 46 001024 - 57 - 3 48 ENDOSULFAN, ALPHA 1018.4 57 000959 - 98 - 8 49 CIS - CHLORDANE 1016.1 59 005103 - 71 - 9 50 CARBO N TETRACHLORIDE 1015.5 47 000056 - 23 - 5 51 AROCLOR 1016 1011.9 51 012674 - 11 - 2 52 COBALT 1010.9 49 007440 - 48 - 4 53 PENTACHLOROPHENOL 1009.0 45 000087 - 86 - 5 54 DDT, O,P' - 1007.9 50 000789 - 02 - 6 55 METHOXYCHLOR 1006.3 61 000072 - 43 - 5 56 ENDOSULFAN SULFATE 100 3.9 55 001031 - 07 - 8 57 NICKEL 998.7 53 007440 - 02 - 0 58 DI - N - BUTYL PHTHALATE 997.3 52 000084 - 74 - 2 59 ENDRIN KETONE 992.0 63 053494 - 70 - 5 60 DIBROMOCHLOROPROPANE 983.0 60 067708 - 83 - 2 61 BENZO(K)FLUORANTHENE 972.2 62 000207 - 08 - 9 62 XYLENES, TOTAL 969.2 58 001330 - 20 - 7 63 TRANS - CHLORDANE 968.3 64 005103 - 74 - 2 64 ENDOSULFAN, BETA 967.6 67 033213 - 65 - 9 65 CHLORPYRIFOS 963.9 127 002921 - 88 - 2 66 CHROMIUM(VI) TRIOXIDE 960.0 65 001333 - 82 - 0 67 AROCLOR 1232 958.2 68 011141 - 16 - 5 68 ENDRIN ALDEHYDE 957.7 69 007421 - 9 3 - 4 69 METHANE 953.4 66 000074 - 82 - 8 70 2 - HEXANONE 941.4 72 000591 - 78 - 6 71 2,3,7,8 - TETRACHLORODIBENZO - P - DIOXIN 940.9 73 001746 - 01 - 6 72 3,3' - DICHLOROBENZIDINE 940.6 40 000091 - 94 - 1 73 BENZOFLUORANTHENE 935.7 70 056832 - 73 - 6 74 TOLUENE 924.1 71 000108 - 88 - 3 75 ZINC 919.1 74 007440 - 66 - 6 76 DI(2 - ETHYLHEXYL)PHTHALATE 908.0 76 000117 - 81 - 7 77 PENTACHLOROBENZENE 906.8 155 000608 - 93 - 5 78 CHROMIUM 897.5 77 007440 - 47 - 3 79 AROCLOR 1240 888.3 81 071328 - 89 - 7 80 NAPHTHALENE 881.4 78 000091 - 20 - 3 81 1,1 - DICHLOROETH ENE 879.5 79 000075 - 35 - 4 82 2,4,6 - TRINITROTOLUENE 877.5 82 000118 - 96 - 7

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### D ISEASE 

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### 2011 PRIORITY LIST O F HAZARDOUS SUBSTANC ES

3 2011 Rank Substance Name Total Points 2007

Rank CAS # 83 2,4,6 - TRICHLOROPHENOL 866.4 86 000088 - 06 - 2 84 BIS(2 - CHLOROETHYL) ETHER 866.3 88 000111 - 44 - 4 85 BROMODICHLOROETHANE 866.2 83 000683 - 53 - 4 86 METHYLENE CHLORIDE 865.6 80 000075 - 09 - 2 87 DDD, O,P' - 865.6 151 000053 - 19 - 0 88 HYDRAZINE 860.8 84 000302 - 01 - 2 89 2,4 - DINITROPHENOL 858.4 87 000051 - 28 - 5 90 4,4' - METHYLENEBIS(2 - CHLOROANILINE) 857.2 152 000101 - 14 - 4 91 1,2 - DICHLOROETHANE 853.6 85 000107 - 06 - 2 92 THIOCYANATE 845.8 89 000302 - 04 - 5 93 HEXACHLOROBENZENE 844.3 93 000118 - 74 - 1 94 ASBESTOS 841.4 90 001332 - 21 - 4 95 RADIUM - 226 833.3 95 013982 - 63 - 3 96 RDX (CYCLOTRIMETHYLENETRINITRAMINE) 831.8 92 000121 - 82 - 4 97 URANIUM 831.8 98 007440 - 61 - 1 98 2,4 - DINITROTOLUENE 831.2 94 000121 - 14 - 2 9 9 ETHION 829.9 96 000563 - 12 - 2 100 RADIUM 827.7 100 007440 - 14 - 4 101 4,6 - DINITRO - O - CRESOL 827.3 102 000534 - 52 - 1 102 THORIUM 823.4 101 007440 - 29 - 1 103 DIMETHYLARSINIC ACID 821.2 75 000075 - 60 - 5 104 CHLORINE 820.6 91 007782 - 50 - 5 105 RADON 818.6 105 010043 - 92 - 2 106 1,3,5 - TRINITROBENZENE 818.6 103 000099 - 35 - 4 107 HEXACHLOROCYCLOHEXANE, ALPHA - 817.3 115 000319 - 84 - 6 108 RADIUM - 228 815.3 106 015262 - 20 - 1 109 THORIUM - 230 813.7 107 014269 - 63 - 7 110 1,1,1 - TRICHLOROETHANE 812.4 97 000071 - 55 - 6 111 URANIUM - 235 81 2.1 107 015117 - 96 - 1 112 URANIUM - 234 809.6 111 013966 - 29 - 5 113 THORIUM - 228 809.5 113 014274 - 82 - 9 114 RADON - 222 809.3 114 014859 - 67 - 7 115 COAL TARS 808.2 118 008007 - 45 - 2 116 ETHYLBENZENE 807.7 99 000100 - 41 - 4 117 CHLOROBENZENE 807.0 104 000108 - 90 - 7 118 N - NITROSODI - N - PROPYLAMINE 806.9 112 000621 - 64 - 7 119 CHRYSOTILE ASBESTOS 806.2 119 012001 - 29 - 5 120 METHYLMERCURY 806.0 123 022967 - 92 - 6 120 PLUTONIUM - 239 806.0 121 015117 - 48 - 3 122 POLONIUM - 210 805.6 122 013981 - 52 - 7 123 PLUTONIUM - 238 805.2 124 013981 - 16 - 3

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### T OXIC 

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### D ISEASE 

### R EGI STRY 

### 2011 PRIORITY LIST O F HAZARDOUS SUBSTANC ES

4 2011 Rank Substance Name Total Points 2007

Rank CAS # 124 LEAD - 210 805.1 125 014255 - 04 - 0 125 COPPER 804.7 128 007440 - 50 - 8 126 BARIUM 804.7 109 007440 - 39 - 3 127 AMOSITE ASBESTOS 804.3 131 012172 - 73 - 5 127 PLUTONIUM 804.3 126 007440 - 07 - 5 127 STRONTIUM - 90 804.3 119 010098 - 97 - 2 130 RADON - 220 804.2 130 022 481 - 48 - 7 131 AMERICIUM - 241 803.8 129 086954 - 36 - 1 132 TRIBUTYLTIN 802.9 134 000688 - 73 - 3 133 FLUORANTHENE 802.6 110 000206 - 44 - 0 134 AZINPHOS - METHYL 802.6 135 000086 - 50 - 0 135 CHLORDECONE 802.1 138 000143 - 50 - 0 136 NEPTUNIUM - 237 801.9 136 013994 - 20 - 2 137 HYDROGEN CYANIDE 801.5 133 000074 - 90 - 8 138 PLUTONIUM - 240 801.4 138 014119 - 33 - 6 139 1,2,3 - TRICHLOROBENZENE 800.3 116 000087 - 61 - 6 140 MANGANESE 799.4 117 007439 - 96 - 5 141 S,S,S - TRIBUTYL PHOSPHOROTRITHIOATE 797.6 141 000078 - 48 - 8 142 CHRYSENE 793.4 137 00 0218 - 01 - 9 143 2,4,5 - TRICHLOROPHENOL 790.4 222 000095 - 95 - 4 144 POLYBROMINATED BIPHENYLS 784.3 143 067774 - 32 - 7 145 DICOFOL 783.8 144 000115 - 32 - 2 146 SELENIUM 778.3 147 007782 - 49 - 2 147 1,1,2,2 - TETRACHLOROETHANE 777.5 146 000079 - 34 - 5 148 HEPTACHLORODIBEN ZO - P - DIOXIN 773.8 154 037871 - 00 - 4 149 PARATHION 773.5 145 000056 - 38 - 2 150 HEXACHLOROCYCLOHEXANE, TECHNICAL GRADE 773.2 148 000608 - 73 - 1 151 TRICHLOROFLUOROETHANE 772.4 149 027154 - 33 - 2 152 BROMINE 770.1 142 007726 - 95 - 6 153 HEPTACHLORODIBENZOFURAN 755.5 166 038998 - 75 - 3 154 TRIFLURALIN 754.3 150 001582 - 09 - 8 155 1,3 - BUTADIENE 750.4 156 000106 - 99 - 0 156 1,2,3,4,6,7,8,9 - OCTACHLORODIBENZOFURAN 742.9 162 039001 - 02 - 0 157 AMMONIA 741.8 157 007664 - 41 - 7 158 2 - METHYLNAPHTHALENE 728.9 158 000091 - 57 - 6 159 1,4 - DIC HLOROBENZENE 725.5 159 000106 - 46 - 7 160 1,1 - DICHLOROETHANE 725.0 160 000075 - 34 - 3 161 2,3,4,7,8 - PENTACHLORODIBENZOFURAN 723.6 168 057117 - 31 - 4 162 NALED 720.6 235 000300 - 76 - 5 163 HEXACHLOROCYCLOPENTADIENE 718.1 165 000077 - 47 - 4 164 1,2 - DIPHENYLHYDRAZINE 7 17.9 167 000122 - 66 - 7

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### D ISEASE 

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### 2011 PRIORITY LIST O F HAZARDOUS SUBSTANC ES

5 2011 Rank Substance Name Total Points 2007

Rank CAS # 165 1,1,2 - TRICHLOROETHANE 717.0 163 000079 - 00 - 5 166 PHORATE 715.2 225 000298 - 02 - 2 167 TRICHLOROETHANE 713.8 164 025323 - 89 - 1 168 ACENAPHTHENE 711.8 161 000083 - 32 - 9 169 TETRACHLOROBIPHENYL 709.2 169 026914 - 33 - 0 170 OXYCHLORDANE 705 .5 171 027304 - 13 - 8 171 PALLADIUM 705.4 180 007440 - 05 - 3 172 CRESOL, PARA - 704.8 170 000106 - 44 - 5 173 INDENO(1,2,3 - CD)PYRENE 702.6 174 000193 - 39 - 5 174 GAMMA - CHLORDENE 701.9 175 056641 - 38 - 4 175 1,2 - DICHLOROBENZENE 698.0 172 000095 - 50 - 1 176 TETRACHLOROPHE NOL 697.0 177 025167 - 83 - 3 177 1,2 - DICHLOROETHENE, TRANS - 695.5 173 000156 - 60 - 5 178 CHLOROETHANE 688.9 183 000075 - 00 - 3 179 PHENOL 688.4 182 000108 - 95 - 2 180 P - XYLENE 686.6 185 000106 - 42 - 3 181 ALUMINUM 684.7 187 007429 - 90 - 5 182 CARBON DISULFIDE 683.0 17 6 000075 - 15 - 0 183 CARBON MONOXIDE 682.2 189 000630 - 08 - 0 184 2,4 - DIMETHYLPHENOL 680.5 188 000105 - 67 - 9 185 DIBENZOFURAN 677.3 186 000132 - 64 - 9 186 ACETONE 676.5 184 000067 - 64 - 1 187 HEXACHLOROETHANE 669.4 197 000067 - 72 - 1 188 BUTYL METHYL PHTHALATE 667.4 194 034006 - 76 - 3 189 CHLOROMETHANE 666.3 193 000074 - 87 - 3 190 HEXACHLORODIBENZOFURAN 660.1 181 055684 - 94 - 1 191 BUTYL BENZYL PHTHALATE 659.1 195 000085 - 68 - 7 192 HYDROGEN SULFIDE 656.3 191 007783 - 06 - 4 193 DICHLORVOS 655.5 240 000062 - 73 - 7 194 CRESOL, ORTH O - 653.4 196 000095 - 48 - 7 195 DIBENZOFURANS, CHLORINATED 653.0 236 042934 - 53 - 2 196 HEXACHLORODIBENZO - P - DIOXIN 651.7 153 034465 - 46 - 8 197 VANADIUM 649.9 198 007440 - 62 - 2 198 N - NITROSODIMETHYLAMINE 648.3 199 000062 - 75 - 9 199 1,2,4 - TRICHLOROBENZENE 647.4 200 000120 - 82 - 1 200 ETHOPROP 643.7 236 013194 - 48 - 4 201 TETRACHLORODIBENZO - P - DIOXIN 641.5 202 041903 - 57 - 5 202 BROMOFORM 635.1 201 000075 - 25 - 2 203 PENTACHLORODIBENZOFURAN 631.7 192 030402 - 15 - 4 204 1,3 - DICHLOROBENZENE 628.6 203 000541 - 73 - 1 205 PENTACHLOROD IBENZO - P - DIOXIN 625.9 204 036088 - 22 - 9

### A GENCY FOR 

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### D ISEASE 

### R EGI STRY 

### 2011 PRIORITY LIST O F HAZARDOUS SUBSTANC ES

6 2011 Rank Substance Name Total Points 2007

Rank CAS # 206 N - NITROSODIPHENYLAMINE 625.8 205 000086 - 30 - 6 207 2,3,7,8 - TETRACHLORODIBENZOFURAN 618.9 207 051207 - 31 - 9 208 2,4 - DICHLOROPHENOL 618.5 209 000120 - 83 - 2 209 2,3 - DIMETHYLNAPHTHALENE 617.5 New 000581 - 40 - 8 210 1,4 - DIO XANE 613.5 210 000123 - 91 - 1 211 FLUORINE 613.3 211 007782 - 41 - 4 212 2 - BUTANONE 611.1 208 000078 - 93 - 3 213 1,2 - DICHLOROETHYLENE 610.4 206 000540 - 59 - 0 214 CESIUM - 137 610.0 213 010045 - 97 - 3 214 CHROMIC ACID 610.0 215 007738 - 94 - 5 216 NITRITE 609.0 212 014797 - 65 - 0 217 SILVER 608.1 214 007440 - 22 - 4 218 POTASSIUM - 40 607.6 217 013966 - 00 - 2 219 DINITROTOLUENE 607.3 218 025321 - 14 - 6 220 NITRATE 606.0 216 014797 - 55 - 8 221 COAL TAR PITCH 605.2 220 065996 - 93 - 2 222 THORIUM - 227 605.0 221 015623 - 47 - 9 223 ARSENIC ACID 604.3 223 007778 - 39 - 4 224 ARSENIC TRIOXIDE 603.8 224 001327 - 53 - 3 225 BENZOPYRENE 602.9 226 073467 - 76 - 2 226 CHLORDANE, TECHNICAL 602.5 228 012789 - 03 - 6 227 STROBANE 602.5 230 008001 - 50 - 1 228 4 - AMINOBIPHENYL 602.4 232 000092 - 67 - 1 228 PYRETHRUM 602.4 232 008003 - 34 - 7 230 ARSINE 602.4 234 007784 - 42 - 1 230 DIMETHOATE 602.4 229 000060 - 51 - 5 232 ANTIMONY 602.2 219 007440 - 36 - 0 233 CARBOPHENOTHION 601.9 238 000786 - 19 - 6 234 ALPHA - CHLORDENE 601.4 238 056534 - 02 - 2 234 IODINE - 131 601.4 132 010043 - 66 - 0 234 MERCUR IC CHLORIDE 601.4 241 007487 - 94 - 7 234 SODIUM ARSENITE 601.4 241 007784 - 46 - 5 234 URANIUM - 233 601.4 178 013968 - 55 - 3 239 DIBROMOCHLOROMETHANE 600.5 249 000124 - 48 - 1 240 CRESOLS 597.1 227 001319 - 77 - 3 241 FORMALDEHYDE 596.0 244 000050 - 00 - 0 242 DICHLOROBENZ ENE 595.4 254 025321 - 22 - 6 243 2,4 - D ACID 594.5 248 000094 - 75 - 7 244 2 - CHLOROPHENOL 591.1 245 000095 - 57 - 8 245 BUTYLATE 589.9 251 002008 - 41 - 5 246 PHENANTHRENE 588.3 246 000085 - 01 - 8

### A GENCY FOR 

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### D ISEASE 

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### 2011 PRIORITY LIST O F HAZARDOUS SUBSTANC ES

7 2011 Rank Substance Name Total Points 2007

Rank CAS # 247 DIMETHYL FORMAMIDE 585.3 252 000068 - 12 - 2 248 4 - NITROPHENOL 580.0 257 000100 - 02 - 7 249 DIURON 578.7 250 000330 - 54 - 1 250 TETRACHLOROETHANE 576.7 190 025322 - 20 - 7 251 DICHLOROETHANE 567.8 256 001300 - 21 - 6 252 ETHYL ETHER 565.2 255 000060 - 29 - 7 253 PYRENE 564.1 253 000129 - 00 - 0 254 DIMETHYLANILINE 561.8 New 000121 - 69 - 7 255 1 ,3 - DICHLOROPROPENE, CIS - 561.0 258 010061 - 01 - 5 256 1,2,3,4,6,7,8 - HEPTACHLORODIBENZO - P - DIOXIN 558.9 263 035822 - 46 - 9 257 PHOSPHINE 555.2 259 007803 - 51 - 2 258 TRICHLOROBENZENE 555.1 260 012002 - 48 - 1 259 2,6 - DINITROTOLUENE 554.4 261 000606 - 20 - 2 260 FLUORIDE ION 549.9 262 016984 - 48 - 8 261 1,2,3,4,6,7,8 - HEPTACHLORODIBENZOFURAN 548.8 273 067562 - 39 - 4 262 PENTAERYTHRITOL TETRANITRATE 548.2 265 000078 - 11 - 5 263 1,3 - DICHLOROPROPENE, TRANS - 548.0 266 010061 - 02 - 6 264 ACRYLONITRILE 543.2 274 000107 - 13 - 1 265 BIS(2 - E THYLHEXYL)ADIPATE 542.4 267 000103 - 23 - 1 266 CARBAZOLE 538.6 268 000086 - 74 - 8 267 METOLACHLOR 538.2 New 051218 - 45 - 2 268 2 - CHLOROANILINE 537.9 New 000095 - 51 - 2 269 1,2,3 - TRICHLOROPROPANE 536.1 New 000096 - 18 - 4 270 CARBARYL 535.5 272 000063 - 25 - 2 271 1,2 - DI CHLOROETHENE, CIS - 533.8 270 000156 - 59 - 2 272 METHYL ISOBUTYL KETONE 529.6 269 000108 - 10 - 1 273 STYRENE 529.4 271 000100 - 42 - 5 274 THALLIUM 525.3 New 007440 - 28 - 0 275 1,2,3,7,8,9 - HEXACHLORODIBENZOFURAN 524.3 New 072918 - 21 - 9 

### Substances were assigned the s ame rank when two (or more) substances received equivalent total point scores. CAS #= Chemical Ab stracts Service Registry Number www.atsdr.cdc.gov/SPL