PFAS Detections in Maryland ZIP Codes — 2026

Out of 210 ZIP codes with data in Maryland, these are the highest-ranked areas for pfas status. See also: National ZIP Codes with PFAS Detections in Water | All Maryland Rankings

Statistic	Value
ZIP codes ranked	210
Highest value	0.1 ppt
Median value	0.0 ppt
State	Maryland

Top 100 Worst ZIP Codes

Rank	ZIP Code	City	State	PFAS Status	Safety Score
1	21157	Westminster	MD	0.1 ppt	64/100
2	21788	Thurmont	MD	0.0 ppt	65/100
3	21703	Frederick	MD	0.0 ppt	64/100
4	21921	Elkton	MD	0.0 ppt	66/100
5	21771	Mount Airy	MD	0.0 ppt	69/100
6	21042	Ellicott City	MD	0.0 ppt	59/100
7	21801	Salisbury	MD	0.0 ppt	59/100
8	21804	Salisbury	MD	0.0 ppt	59/100
9	21074	Hampstead	MD	0.0 ppt	65/100
10	21102	Manchester	MD	0.0 ppt	70/100
11	20837	Poolesville	MD	0.0 ppt	68/100
12	21787	Taneytown	MD	0.0 ppt	65/100
13	21901	North East	MD	0.0 ppt	59/100
14	21914	Charlestown	MD	0.0 ppt	55/100
15	21014	Bel Air	MD	0.0 ppt	57/100
16	21015	Bel Air	MD	0.0 ppt	62/100
17	21047	Fallston	MD	0.0 ppt	55/100
18	21050	Forest Hill	MD	0.0 ppt	55/100
19	21001	Aberdeen	MD	0.0 ppt	60/100
20	21005	Aberdeen Proving Ground	MD	0.0 ppt	40/100
21	21769	Middletown	MD	0.0 ppt	61/100
22	21713	Boonsboro	MD	0.0 ppt	69/100
23	21756	Keedysville	MD	0.0 ppt	53/100
24	21811	Berlin	MD	0.0 ppt	78/100
25	20601	Waldorf	MD	0.0 ppt	72/100
26	20607	Accokeek	MD	0.0 ppt	78/100
27	20613	Brandywine	MD	0.0 ppt	78/100
28	20623	Cheltenham	MD	0.0 ppt	63/100
29	20705	Beltsville	MD	0.0 ppt	45/100
30	20706	Lanham	MD	0.0 ppt	50/100
31	20707	Laurel	MD	0.0 ppt	78/100
32	20708	Laurel	MD	0.0 ppt	78/100
33	20710	Bladensburg	MD	0.0 ppt	53/100
34	20712	Mount Rainier	MD	0.0 ppt	53/100
35	20715	Bowie	MD	0.0 ppt	77/100
36	20716	Bowie	MD	0.0 ppt	82/100
37	20720	Bowie	MD	0.0 ppt	77/100
38	20721	Bowie	MD	0.0 ppt	77/100
39	20722	Brentwood	MD	0.0 ppt	45/100
40	20723	Laurel	MD	0.0 ppt	65/100
41	20735	Clinton	MD	0.0 ppt	50/100
42	20737	Riverdale	MD	0.0 ppt	40/100
43	20738	Riverdale	MD	0.0 ppt	53/100
44	20740	College Park	MD	0.0 ppt	45/100
45	20742	College Park	MD	0.0 ppt	40/100
46	20743	Capitol Heights	MD	0.0 ppt	55/100
47	20744	Fort Washington	MD	0.0 ppt	50/100
48	20745	Oxon Hill	MD	0.0 ppt	55/100
49	20746	Suitland	MD	0.0 ppt	55/100
50	20747	District Heights	MD	0.0 ppt	55/100
51	20748	Temple Hills	MD	0.0 ppt	50/100
52	20769	Glenn Dale	MD	0.0 ppt	63/100
53	20770	Greenbelt	MD	0.0 ppt	53/100
54	20771	Greenbelt	MD	0.0 ppt	40/100
55	20772	Upper Marlboro	MD	0.0 ppt	50/100
56	20773	Upper Marlboro	MD	0.0 ppt	53/100
57	20774	Upper Marlboro	MD	0.0 ppt	55/100
58	20781	Hyattsville	MD	0.0 ppt	45/100
59	20782	Hyattsville	MD	0.0 ppt	40/100
60	20783	Hyattsville	MD	0.0 ppt	45/100
61	20784	Hyattsville	MD	0.0 ppt	55/100
62	20785	Hyattsville	MD	0.0 ppt	55/100
63	20787	Hyattsville	MD	0.0 ppt	40/100
64	20790	Capitol Heights	MD	0.0 ppt	53/100
65	20812	Glen Echo	MD	0.0 ppt	53/100
66	20814	Bethesda	MD	0.0 ppt	65/100
67	20815	Chevy Chase	MD	0.0 ppt	45/100
68	20816	Bethesda	MD	0.0 ppt	65/100
69	20817	Bethesda	MD	0.0 ppt	60/100
70	20818	Cabin John	MD	0.0 ppt	45/100
71	20830	Olney	MD	0.0 ppt	40/100
72	20832	Olney	MD	0.0 ppt	53/100
73	20833	Brookeville	MD	0.0 ppt	53/100
74	20841	Boyds	MD	0.0 ppt	73/100
75	20850	Rockville	MD	0.0 ppt	53/100
76	20851	Rockville	MD	0.0 ppt	53/100
77	20852	Rockville	MD	0.0 ppt	45/100
78	20853	Rockville	MD	0.0 ppt	45/100
79	20854	Potomac	MD	0.0 ppt	35/100
80	20855	Derwood	MD	0.0 ppt	53/100
81	20857	Rockville	MD	0.0 ppt	40/100
82	20859	Potomac	MD	0.0 ppt	33/100
83	20860	Sandy Spring	MD	0.0 ppt	53/100
84	20861	Ashton	MD	0.0 ppt	53/100
85	20866	Burtonsville	MD	0.0 ppt	53/100
86	20868	Spencerville	MD	0.0 ppt	40/100
87	20871	Clarksburg	MD	0.0 ppt	64/100
88	20872	Damascus	MD	0.0 ppt	73/100
89	20874	Germantown	MD	0.0 ppt	45/100
90	20875	Germantown	MD	0.0 ppt	40/100
91	20876	Germantown	MD	0.0 ppt	53/100
92	20877	Gaithersburg	MD	0.0 ppt	53/100
93	20878	Gaithersburg	MD	0.0 ppt	45/100
94	20879	Gaithersburg	MD	0.0 ppt	53/100
95	20880	Washington Grove	MD	0.0 ppt	40/100
96	20882	Gaithersburg	MD	0.0 ppt	53/100
97	20884	Gaithersburg	MD	0.0 ppt	40/100
98	20885	Gaithersburg	MD	0.0 ppt	40/100
99	20886	Montgomery Village	MD	0.0 ppt	53/100
100	20892	Bethesda	MD	0.0 ppt	66/100

Methodology

PFAS detection data comes from EPA UCMR5 monitoring, state-level testing programs, and Consumer Confidence Reports. ZIP codes are ranked by maximum PFAS concentration detected. The EPA has set MCLs of 4 ppt for PFOA and PFOS individually. PFAS are persistent chemicals that do not break down in the environment.

Data sources: EPA Safe Drinking Water Information System (SDWIS), FEMA National Flood Insurance Program, EPA radon zone maps, EIA electricity rates, and Consumer Confidence Reports. Last updated: 2026-06-04.

Frequently Asked Questions

What are PFAS?

PFAS (per- and polyfluoroalkyl substances) are synthetic chemicals used in non-stick coatings, firefighting foam, and food packaging since the 1940s. They are called "forever chemicals" because they do not break down naturally. PFAS are linked to cancer, liver damage, thyroid disease, and immune system suppression.

How can I remove PFAS from my water?

Reverse osmosis (RO) and granular activated carbon (GAC) filters are effective at removing most PFAS from drinking water. NSF/ANSI 53 or 58 certified filters are recommended. Boiling water does NOT remove PFAS.