Constituents of Emerging Concern

Water quality regulations have traditionally focused on pollutants from industry and a small number of naturally occurring contaminants. Recently, a diverse group of relatively unmonitored chemicals such as pharmaceuticals, personal care products and other trace organic chemicals has emerged as a new issue for regulators to address.

The State Water Resources Control Board adopted a Recycled Water Policy in 2009 that attempts to incorporate the most current science on constituents of emerging concern (CECs) into regulatory policies for use by various state agencies. As part of this policy, the Southern California Coastal Water Resources Project has convened a panel of six experts to provide recommendations to the State Board.

ACWA serves in an advisory capacity to panel, which is expected to issue final recommendations in May 2010.

This "blue ribbon" panel is addressing the following questions:

1. What are the appropriate constituents to be monitored in recycled water, and what are the applicable monitoring methods and detection limits?
2. What toxicological information is available for these constituents?
3. Would the constituent list change based on level of treatment? If so, how?
4. What are the possible indicators (i.e. surrogates) that represent a suite of CECs?
5. What levels of CECs should trigger enhanced monitoring in recycled, ground or surface waters?

The panel released a draft report in April 2010 that included a conceptual framework for determining which CECs should be monitored and recommended a phased approach to implementing CEC monitoring programs for recycled water. The report is available here.

ACWA submitted joint comments on the draft report on May 14, 2010. The comments, submitted by ACWA, WateReuse California, the National Water Research Institute and the California Association of Sanitation Agencies, identifies questions and recommendations for consideration by an expert panel established by the State Water Resources Control Board. The comments can be read here.

A PowerPoint presentation on the panel's draft recommendations from a May 21 public meeting can be viewed here.

A second, related panel has also been formed to address CECs in coastal and marine ecosystems.

• More on the panels is available here

Background on CECs and Endocrine Disruptors

Scientists say there is some evidence that pharmaceuticals and personal care products in the water supply may act as endocrine disruptors in humans and wildlife. A variety of laboratory studies indicate these compounds interfere with the endocrine systems of animals, and there is strong evidence that chemical exposure has been associated with adverse developmental and reproductive effects in fish and wildlife.

Since wastewater treatment plants are not designed to remove them, pharmaceuticals and personal care products mostly enter the environment through wastewater discharges. New sampling data shows that endocrine disruptors are commonly found downstream of intensely urbanized areas and animal production facilities.

Over the past 30 years, water quality regulations have focused on "traditional" pollutants from industry and a small number of naturally occurring contaminants. However, the emergence of endocrine disrupting chemicals is triggering a shift in the way water quality officials view and address pollution sources. While these chemicals have likely been present in our water supply sources for as long as such consumer products have been in use, they have gone virtually undetected until recently as better technology has improved our ability to detect them.

While technology allows detection of consumer products in waterways, there is currently no frame of reference to determine what risks may or may not exist.  ACWA believes that more scientific data is needed to understand the risks posed by endocrine disruptors and supports federal funding for research to ascertain their public health threat.