Arsenic Contamination

Arsenic in Missouri Drinking Water

Ranked by arsenic violation count · Data from EPA SDWIS & UCMR

Cities Tested

Has Violations

100%

% Has Violations

5.6 violations

State Avg

▼ 0% vs national

vs National

426

Health Violations

Analysis

Arsenic in Missouri: what the data shows

Missouri has 98 cities with arsenic-related violations on record. Arsenic contamination is a federal MCL violation at levels above 10 µg/L (10 ppb). The state has 98 cities with at least one arsenic violation. Arsenic enters drinking water primarily through erosion of natural deposits, particularly in western states with arsenite-bearing geology. Industrial sources include mining runoff, glass manufacturing, and semiconductor production. Groundwater systems are significantly more likely to have arsenic issues than surface water systems. Long-term arsenic exposure above the MCL increases the risk of bladder, lung, and skin cancer, as well as cardiovascular disease and diabetes. Reverse osmosis and specialized arsenic-removal media are the most effective point-of-use treatment options.

Comparison

Cities exceeding 10 µg/L EPA MCL

Missouri

100%

98 of 98 cities

← = Exactly at national rate

National avg

100%

5489 of 5489 cities

City Map

Arsenic data across Missouri

Each dot is a city with arsenic violation data. Cities with at least one arsenic-related violation are highlighted. Size reflects population served.

Worst Offenders

Top 10 cities by arsenic level in Missouri

Highest Arsenic levels (violations)

All Cities

All Missouri cities ranked by arsenic level

#	City	Level	Violations?	Violations	Grade
1	Yuma	89 violations	Yes	99	F
2	Des Peres	74 violations	Yes	2149	F
3	Clifton	65 violations	Yes	35	D
4	Flagstaff	61 violations	Yes	18	D
5	White Hills	38 violations	Yes	29	D
6	White Hills	38 violations	Yes	21	D
7	Cornville	15 violations	Yes	1	B-
8	Ocala	8 violations	Yes	9	F
9	Aurora	7 violations	Yes	90	D
10	Sullivan	6 violations	Yes	40	D
11	Bunn	6 violations	Yes	38	F
12	Salome	6 violations	Yes	11	D+
13	Carthage	5 violations	Yes	21	D+
14	House Springs	5 violations	Yes	7	B+
15	Kimberling City	5 violations	Yes	110	D
16	Summerfield	5 violations	Yes	7	C
17	Mountain Grove	4 violations	Yes	20	C+
18	Reeds Spring	4 violations	Yes	54	D
19	Bourbon	4 violations	Yes	14	B+
20	Festus	3 violations	Yes	20	C
21	Rogersville	3 violations	Yes	47	D
22	Forsyth	3 violations	Yes	27	D
23	Branson West	3 violations	Yes	47	D
24	Salome	3 violations	Yes	2	B-
25	Wappapello	3 violations	Yes	12	D+
26	Hornersville	3 violations	Yes	6	B+
27	Rolla	2 violations	Yes	32	D
28	Farmington	2 violations	Yes	251	D
29	Sedalia	2 violations	Yes	60	F
30	Platte City	2 violations	Yes	9	B
31	Neosho	2 violations	Yes	21	C-
32	Imperial	2 violations	Yes	1	B+
33	De Soto	2 violations	Yes	22	B-
34	Bunn	2 violations	Yes	17	C+
35	St. Robert	2 violations	Yes	19	D
36	Chaffee	2 violations	Yes	9	B+
37	Blue Eye	2 violations	Yes	43	D
38	Ocklawaha	2 violations	Yes	0	B
39	Galena	2 violations	Yes	31	C-
40	Bertrand	2 violations	Yes	10	C
41	Kansas City	1 violations	Yes	1	B
42	Springfield	1 violations	Yes	59	F
43	Columbia	1 violations	Yes	52	C
44	O Fallon	1 violations	Yes	10	F
45	Joplin	1 violations	Yes	53	F
46	Cape Girardeau	1 violations	Yes	127	D
47	Branson	1 violations	Yes	70	D
48	Ozark	1 violations	Yes	65	F
49	Waynesville	1 violations	Yes	6	C+
50	Union	1 violations	Yes	56	D
51	Hillsboro	1 violations	Yes	37	D+
52	Lake Ozark	1 violations	Yes	14	D
53	Beverly Hills	1 violations	Yes	4	B-
54	Beverly Hills	1 violations	Yes	3	B+
55	Boonville	1 violations	Yes	46	C
56	Camdenton	1 violations	Yes	73	F
57	Osage Beach	1 violations	Yes	30	D
58	Willard	1 violations	Yes	16	A-
59	Pacific	1 violations	Yes	47	D
60	Hollister	1 violations	Yes	46	D
61	Mount Vernon	1 violations	Yes	15	D
62	Senath	1 violations	Yes	11	D
63	Ava	1 violations	Yes	16	C
64	Stockton	1 violations	Yes	49	D
65	Catalina	1 violations	Yes	0	A-
66	Crocker	1 violations	Yes	14	B+
67	Shell Knob	1 violations	Yes	60	D
68	Merriam Woods	1 violations	Yes	0	B+
69	Fordland	1 violations	Yes	10	B-
70	Ocklawaha	1 violations	Yes	0	A-
71	Crane	1 violations	Yes	7	C
72	Ash Grove	1 violations	Yes	7	B+
73	Sweet Springs	1 violations	Yes	14	B+
74	Lilbourn	1 violations	Yes	8	D+
75	Belleview	1 violations	Yes	16	C+
76	Loose Creek	1 violations	Yes	0	B
77	Dixon	1 violations	Yes	9	B+
78	Loose Creek	1 violations	Yes	0	B
79	Wellsville	1 violations	Yes	70	B
80	Pierce City	1 violations	Yes	8	B
81	Summerfield	1 violations	Yes	0	A
82	Jacksonville	1 violations	Yes	5	A-
83	Ormond Beach	1 violations	Yes	1	B+
84	Benton	1 violations	Yes	11	F
85	Jasper	1 violations	Yes	4	A
86	Peeples Valley	1 violations	Yes	11	C
87	Melbourne Beach	1 violations	Yes	8	B
88	Umatilla	1 violations	Yes	1	A
89	Heber	1 violations	Yes	0	B-
90	Walnut Grove	1 violations	Yes	7	B-
91	Martinsburg	1 violations	Yes	2	C
92	Alba	1 violations	Yes	10	A-
93	Gadsden	1 violations	Yes	3	B-
94	Gadsden	1 violations	Yes	3	B-
95	Cardwell	1 violations	Yes	0	C-
96	Tonto Village	1 violations	Yes	2	C-
97	Tonto Village	1 violations	Yes	2	C-
98	Otterville	1 violations	Yes	22	B+

FAQ

Frequently asked questions about arsenic in Missouri

Is arsenic in Missouri tap water a concern?

Yes — 98 cities in Missouri have arsenic-related violations on record. The EPA MCL for arsenic is 10 µg/L. Even at levels below the MCL, long-term arsenic exposure has been linked to cancer and cardiovascular disease.

How can I remove arsenic from my drinking water in Missouri?

Reverse osmosis (RO) systems are the most effective at removing arsenic, typically reducing it by 90% or more. Specialized arsenic-removal media (such as iron-based adsorption filters) are also highly effective. Standard carbon filters and pitcher filters do NOT effectively remove arsenic. If your water comes from a private well, have it tested for arsenic.

Where does arsenic in Missouri water come from?

Arsenic enters drinking water primarily through natural erosion of arsenic-bearing rock formations. It is most common in groundwater systems in the western United States, parts of the Midwest, and New England. Industrial sources include mining, smelting, and agricultural pesticide residues. Groundwater sources are far more likely to contain arsenic than surface water.

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