Indicator Profile of Disinfection By Products in Community Drinking Water Systems

Why Is This Important?

Disinfection by products (DBPs) are formed when disinfectants (such as chlorine chemicals) used during water treatment to destroy harmful bacteria and viruses, react with natural organic matter in water. Trihalomethanes (THMs) and haloacetic acids (HAAs) are produced in the largest amounts. The level of DBPs formed after disinfection depends on the source water, type of treatment, and amount of disinfectant used.

Health risks from exposure to low levels of DBPs are not well understood. Some studies suggest that DBP exposure may increase the risk of bladder and colorectal cancers and reproductive and developmental health effects.

Drinking Water Disinfection By-Products, Number of Community Water Systems with MCL Violations, 1999-2007

::chart - missing::

Data Notes

New or more stringent MCLS for DBPs were phased in between 2003 and 2005. The MCL for total trihalomethanes was lowered from 100 micrograms per liter to 80 micrograms per liter, and a new MCL for haloacetic acids was established at 60 micrograms per liter. Data are presented for community water systems that reported test results for the specified time interval.  There are over 600 community water systems in New Jersey.

Data Sources

New Jersey Department of Environmental Protection, Bureau of Safe Drinking Water; 

Other Graphical Views


The distribution of disinfection by products (total trihalomethane and haloacetic acid) in drinking water by community water system, population served, and year

How We Calculated the Rates

Numerator: Number of community water systems or estimated count of population served, by disinfection by-product concentration in drinking water.
Denominator: Not Applicable

Page Content Updated On 02/04/13, Published on 02/04/13
Environmental Public Health Tracking Project, New Jersey Department of Health, PO Box 369, Trenton, NJ 08625-0369, Phone: 609-826-4984, e-mail: nj.epht@doh.state.nj.us, Web: www.nj.gov/health/epht
The information provided above is from the New Jersey Department of Health's NJSHAD Web site (http://nj.gov/health/shad). The information published on this website may be reproduced without permission. Please use the following citation: "Retrieved Thu, 23 October 2014 1:09:20 from New Jersey Department of Health, Center for Health Statistics, State Health Assessment Data Web site: http://nj.gov/health/shad".

Content updated: Sat, 20 Sep 2014 04:00:46 EDT