Dinoseb in drinking water
1,146 active public water systems in 36 states had a Dinoseb violation in the past three years, and 55 have one that is still unresolved.
You are on Tapcensus, an independent guide to the EPA compliance records of every public water system in the United States. This page explains Dinoseb and lists the water systems whose records include a related violation. It does not show measured levels.
Is Dinoseb in the records for your water system?
Enter a ZIP code, town, or street address to see the water systems that serve your area, their status, and which rules and contaminants appear in their violations.
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What it is and where it comes from
Dinoseb is a dinitrophenol herbicide and pesticide formerly used on crops including soybeans, cereals, and vegetables. Its US pesticide registrations were voluntarily canceled in 1986 after it was found to cause severe reproductive and developmental toxicity. It persists in soil and can leach into groundwater from historically treated agricultural fields.
Health effects
Dinoseb uncouples oxidative phosphorylation, disrupting cellular energy production. Chronic exposure causes reproductive toxicity: impaired sperm production in males and developmental harm, including birth defects, in developing fetuses. EPA has not established a formal carcinogenicity classification. Reproductive-age adults and pregnant women face the greatest risk.
The standard and what a violation means
EPA limit: 0.007 mg/L (7 ppb).
Water systems with a Dinoseb violation, by state
Active public water systems that reported at least one related violation to EPA in the past three years. Each state links to the list of its affected systems.
| State | Systems with violations, 3 yr | Share of active systems | Unresolved |
|---|---|---|---|
| Pennsylvania | 209 | 3% | 7 |
| New York | 119 | 1% | 1 |
| Oklahoma | 96 | 7% | 0 |
| Texas | 84 | 1% | 0 |
| Oregon | 72 | 3% | 3 |
| Illinois | 47 | 1% | 10 |
| Washington | 44 | 1% | 9 |
| Colorado | 37 | 2% | 4 |
| Idaho | 37 | 2% | 3 |
| Montana | 37 | 2% | 1 |
| Connecticut | 30 | 1% | 1 |
| Utah | 29 | 3% | 1 |
| California | 28 | 0% | 1 |
| Indiana | 27 | 1% | 2 |
| Alabama | 26 | 5% | 0 |
| Michigan | 26 | 0% | 0 |
| Alaska | 25 | 2% | 0 |
| Wyoming | 24 | 3% | 1 |
| Vermont | 22 | 2% | 3 |
| Missouri | 19 | 1% | 1 |
| Wisconsin | 19 | 0% | 0 |
| Nevada | 16 | 3% | 0 |
| Arizona | 13 | 1% | 1 |
| Massachusetts | 12 | 1% | 1 |
| North Carolina | 8 | 0% | 1 |
| Rhode Island | 8 | 2% | 0 |
| New Jersey | 7 | 0% | 2 |
| Maine | 6 | 0% | 0 |
| Minnesota | 6 | 0% | 2 |
| South Dakota | 3 | 0% | 0 |
| Virginia | 3 | 0% | 0 |
| North Dakota | 2 | 1% | 0 |
| New Mexico | 2 | 0% | 0 |
| Florida | 1 | 0% | 0 |
| Kentucky | 1 | 0% | 0 |
| New Hampshire | 1 | 0% | 0 |
Largest water systems with a Dinoseb violation
The ten biggest systems, by people served, whose records include a related violation in the past three years.
| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Chicago Cook County |
2,721,308 | 4 | 0 | |
|
Denver Water Board Denver County |
1,287,000 | 3 | 0 | |
|
Pittsburgh Water & Sewer Auth Allegheny County |
520,000 | 3 | 0 | |
|
Gilbert, Town of Gilbert · Maricopa County |
247,600 | 9 | 1 | |
|
Corona, City of Corona · Riverside County |
169,380 | 6 | 0 | |
|
City of Sunnyvale Sunnyvale · Santa Clara County |
157,566 | 5 | 0 | |
|
Rockford Rockford · Winnebago County |
147,051 | 3 | 0 | |
|
Epcor Agua Fria Surprise · Maricopa County |
128,040 | 5 | 0 | |
|
Pasco Water Department Franklin County |
115,102 | 2 | 0 | |
|
Inima USA / Aquaria LLC Dighton · Bristol County |
105,643 | 1 | 0 |
About this data
A system is counted once if any of its violations in the past three years involved Dinoseb, including monitoring and reporting lapses. Rules violated and status in the systems table are for the whole system, not Dinoseb alone. Counts cover active systems in all 50 states and the District of Columbia.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet.