Tapcensus

1,2,4-Trichlorobenzene violations in Maryland

2 active public water systems in Maryland had a 1,2,4-Trichlorobenzene violation in the past three years. What 1,2,4-Trichlorobenzene is and why it matters.

Health effects: Chronic exposure to 1,2,4-trichlorobenzene is associated with changes in adrenal gland function and liver and kidney effects in animal studies. EPA classifies it as a possible human carcinogen (Group C). Long-term exposure above the MCL is the primary concern for public water system violations.

Systems with a 1,2,4-Trichlorobenzene violation

Unresolved first, then largest first
SystemServesStatusRules violated, 3 yrUnresolved
ST Johns Lutheran Church and School
Baltimore County 		140 4 0
Powrmatic Inc.
Carroll County 		35 4 1
About this data

A system is counted once if any of its violations in the past three years involved 1,2,4-Trichlorobenzene, including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not 1,2,4-Trichlorobenzene alone.

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 Maryland 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. Retrieved from ECHO on Oct 11, 2026.