Testing the Waters for Contaminants
Mon, 11/01/2010 - 12:18pm
In other areas, “the presence of pharmaceutical and personal care products (PPCPs) and persistent organic pollutants (POPs) in drinking water have become an area of immense public concern and research by water suppliers, regulatory agencies, and engineering firms,” says Dom Testa, Agilent’s Worldwide Market Development Manager, Santa Clara, Calif. “Some examples of PPCPs are acetaminophen and codeine. Examples of POPs are mercury, fire retardants (polybrominated diphenyl ether or PBDE), and poly-chlorinated biphenyl (PCB). While these compounds have helped to protect the personal health and safety of humans, they create risks and concerns to the environment that are constantly being researched.”
An investigative study by the Associated Press in 2008 discovered that a vast array of pharmaceuticals were detected in the drinking water supplies of 24 major metropolitan areas—from Southern California to Northern New Jersey and from Detroit to Louisville, Ky. Most of the drug sources were found to be in the treated waste water streams where treatment plants were unable to remove all of the drug residue from the waste stream. The drugs got into the waste stream in the first place because of drugs sloughed off from consumers.
PerkinElmer’s NexION ICP-MS offers the simplicity and convenience of a collision cell and the detection limits of a true reaction cell.
“Endocrine disrupter effects are certainly smaller than chronic exposure effects over time,” says Grosser. However, we don’t know the real long-term effects of EDCs, such as their susceptibility to cancer.
To be sure, the effects of the BP Gulf oil spill are just beginning to be monitored and tested. Scientists at the Univ. of North Carolina, Chapel Hill, recently worked with researchers at Aanderaa Data Instruments in Bergen, Norway, to develop, test, and deploy two multisensor arrays designed to detect light hydrocarbons and oxygen depletion associated with oil and gas releases in the Gulf of Mexico. These multisensor arrays can operate in a water column survey mode from a submersible or as a deployed observatory in a site monitoring mode. The sensor array includes advanced conductivity, turbidity, pressure (depth) and current. Aanderaa, a division of ITT Analytics, has a long history of ocean monitoring systems around the globe. The company, for example, recently modernized hydrological measurement stations along the German coast. Seven data buoys and 10 river pile stations were installed along the river Elbe estuary. Each of the data buoys were fitted with a series of sensors to monitor water speed and direction, temperature, pressure, salinity, turbidity and oxygen. Both floating and sea bottom data buoys were installed with data transmitted in real time to the German Waterway and Shipping Administration. The data collected is being used to determine the basic transport processes of sediments, suspended materials, and the morphological behavior of the bottom zone of the tidal river Elbe and their natural and anthropogenic behavior.
Agilent’s 6490 Triple Quad LCMS has the sensitivity to find pharmaceutical and personal care product compounds in drinking water supplies.
Urban water testing
Testing of urban water supplies is relatively well defined. GC-MS and ICP-MS (inductively coupled plasma mass spectroscopy) are the workhorse instruments for water monitoring studies. “However, if you don’t know what you’re looking for, triple quad LC-MS systems are becoming more popular,” says PerkinElmer’s Grosser.
PerkinElmer’s new NexION 300 ICP-MS is a significant advancement in the state-of-the-art ICP-MS. With its unique universal cell technology, users can choose the most important technique for a specific sample or application. There are no restrictions of the gases used or mass range. The instrument can operate in a standard mode, collision mode (with kinetic energy discrimination) or reaction mode (with a scanning quadrupole). The ICP-MS can be used to analyze drinking water, natural water, and waste water per EPA Method 200.8.
Thermo Fisher Scientific’s Spectronic 200 spectrophotometer provides full-wavelength scan data and multi-standard quantitative analyses for wastewater samples.
Similarly, atomic absorbtion instruments can be used to test for lead and arsenic in water per EPA method 200.9. And ICP-OES can be used to test for trace elements in water per EPA Method 200.7.
“The technology, sensitivity, features, and reliability of these instruments (triple quad LC-MS) provide accurate confirmation of these chemical compounds at very low detection levels that meet or exceed regulatory limits,” says Agilent’s Testa. “Agilent Technologies has developed analytical methods in collaboration with leading researchers using our ICP, GC, and LC mass spectrometers. These methods have been developed for more than 30 of the most recognized PPCP compounds.”
While the resolution of these instruments is certainly adequate (especially with triple quad LC-MS systems), there are still limitations and issues in the analyses. “Sample prep is one of the big issues,” says Grosser. “The chromatography systems don’t always separate everything out and the time it takes to actually do the separation or extraction is always too long. More research is needed to improve both of these areas.”
Compounds of Concern in Water. Click to Enlarge.
In situ monitoring with sensors providing the data that’s transmitted online and tied into a control software system has become very efficient, says Grosser.
The instrumentation and technologies used to monitor and test water supplies in the U.S. are basically similar to those used in Europe, Japan and Asia. Globalization has been this aspect of water quality a uniform playing field. What the specific regulatory bodies do with the collected data, however varies from country to country and region to region.
Europe and the U.S. have similar regulations of water quality, however European enforcement is much more stringent than that in the U.S. The U.S. is improving in this area, but it still is behind Europe. Asian countries, not including Japan, have similar regulations as well, but there is basically no enforcement. Industrial growth strategies have preempted the enforcement of regulations that actually could restrict some of that industrial growth. The trend in China may be changing slightly to encourage more enforcement, but they’re still distant from the enforcement seen in the U.S. and Europe. Regulations and enforcement in Japan are equal to that in Europe—the government is and has always been a strong supporter of environmental protection.