The Environmental Protection Agency has urged the nation’s water utilities to develop monitoring and sampling programs for Hexavalent Chromium, in the wake of a study that found the toxic chemical in most of the water supplies tested.
The study, by the nonprofit Environmental Working Group, found Hexavalent Chromium in concentrations that average three times the safety goal being proposed by the state of California. One sample was more than 200 times the proposed California threshold.
On Tuesday (Dec. 21), EPA Administrator Lisa Jackson met with 10 U.S. senators regarding the study. Afterward, she announced a series of actions to address Hexavalent Chromium (also known as Chromium VI, Chromium 6 or CrVI) in drinking water.
Jackson noted, as EWG had, that the study provided only a “snapshot” of the situation but said the results merited more information.
‘Significant Technical Assistance’
“It is clear that the first step is to understand the prevalence of this problem,” Jackson said.
To that end, she said, “EPA will work with local and state officials to get a better picture of exactly how widespread this problem is. In the meantime, EPA will issue guidance to all water systems in the country to help them develop monitoring and sampling programs specifically for Chromium 6.
“We will also offer significant technical assistance to the communities cited in the EWG report with the highest levels of Chromium 6 to help ensure they quickly develop an effective Chromium 6 specific monitoring program.
Applications and Exposures
Hexavalent Chromium has many industrial applications, including chromate pigments in dyes and paints; chromates added as anticorrosive agents to paints, primers and other surface coatings; and chromic acid electroplated onto metal parts to provide a decorative or protective coating.
Chromium 6 exposures are addressed in specific—and increasing—standards for general industry, rules concerning OSHA access to employee medical reports, shipyard employment, marine terminals, and the construction industry.
The EWG report said the chemical was commonly discharged from steel and pulp mills, metal–plating plants and leather–tanning facilities.
In her meeting with the senators, Jackson described EPA’s current Chromium 6 risk assessment, which began in 2008 in response to new evidence of a link between Chromium 6 ingestion and cancer. The risk assessment, which would be the first step to updating the drinking water regulations, will be finalized after an independent scientific peer review in 2011.
Based on the draft risk assessment, EPA will likely revise drinking water regulations, Jackson said. However, she added, any revisions would take place only after an independent science panel had verified the science.
“The science behind Chromium 6 is evolving,” Jackson said. “…Strong science and the law will continue to be the backbone of our decision-making at EPA. EPA takes this matter seriously and we will continue to do all that we can, using good science and the law, to protect people’s health and our environment.”
EPA currently requires testing for total chromium, Jackson said. The testing does not distinguish what percentage of the total chromium is Chromium 6 versus Chromium-3, so EPA’s regulation assumes that the sample is 100% Chromium 6.
According to the most recent data, all public water facilities are in compliance with the existing total chromium standards, Jackson said, but she agreed that Chromium 6 was a contaminant of concern.
Meanwhile, U.S. Sens. Barbara Boxer and Dianne Feinstein say they will introduce legislation that would set a deadline for the EPA to establish an enforceable standard for the chemical. In a letter Tuesday obtained by the Associated Press, Boxer said the Senate environment and public works committee, which she chairs, would hold a hearing on the issue in February.
The Erin Brockovich Case
Chromium 6 gained the public spotlight in 2000, with the hit movie Erin Brockovich.
The movie followed the years-long case by residents of Hinkley, CA, against Pacific Gas & Electric Corp. PG&E used Chromium 6 from 1952 to 1966 to fight corrosion in a cooling tower at the Hinkley Compressor Station. Wastewater eventually dissolved the chemical into unlined ponds.
The utility subsequently agreed to a $333 million settlement with hundreds of residents who blamed the contamination for a variety of health problems including cancer. Recent testing has found that the toxic plume is spreading in the groundwater, and cleanup in the case continues.