EWG's Tap Water Database


2,3,7,8-TCDD (Dioxin)

Beauregard Water Works District #3

Dioxins are contaminants released from chemical manufacturing, pulp and paper bleaching, and incineration of products that contain chlorine. 2,3,7,8-Tetrachlorodibenzodioxin (2,3,7,8-TCDD) is the most toxic chemical in the group of dioxins. Read More.

Dioxins are among the most toxic known environmental pollutants. As a class, dioxins are extremely toxic, persistent and bioaccumulative; these contaminants build up and are stored in fatty tissues and fluids, such as breast milk, and pass from the mother to the child. Most people are exposed to dioxins through the food they eat, primarily from meat, dairy, fish and eggs. In humans, dioxins are associated with cancer, birth defects, damage to the nervous and immune systems, altered metabolism, thyroid disruption, altered menstrual cycling and damage to the cardiovascular system.





Samples exceeding legal limit (MCL)


Samples exceeding
health guidelines

Testing results - average by year

YearAverage resultSamples takenDetectionsRange of results

ppt = parts per trillion.

State and national drinking water standards and health guidelines

Health Guideline 0.0002 ppt

The health guideline of 0.0002 ppt for 2,3,7,8-TCDD was defined by the Environmental Protection Agency as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

ppt = parts per trillion.

EPA Maximum Contaminant
Level (MCL) 0.03 ppt

The enforceable federal standard that defines the highest level of a contaminant allowed in drinking water.

ppt = parts per trillion.

EPA Maximum Contaminant
Level Goal (MCLG)0 ppt

A non-enforceable federal health guideline. For cancer-causing chemicals, these health goals are typically set to zero.

ppt = parts per trillion.

All test results

Date Lab ID Result