The cure for anything is salt water: sweat, tears or the sea.

-Isak Dinesen

For environmental remediation and monitoring projects that require the determination of various trace metals at ambient levels in seawater or brackish water, acquiring reliable measurements can be challenging. The inherently elevated concentrations of dissolved salts can lead to severe physical and chemical interferences during analysis. Therefore, significant dilutions are typically required to analyze these samples by routine methods, which can easily result in detection limits that far exceed the concentrations of target analytes or the ambient water quality criteria.

EPA Method 1640 was developed specifically to provide reliable measurements of metals at ambient levels in seawater. This method provides for a number of preconcentration techniques, combined with analysis by inductively coupled plasma-mass spectrometry (ICP-MS), to overcome the physical and chemical interferences presented by elevated concentrations of salts and other interfering components of seawater. Consequently, ultra-low detection limits can be achieved and the most subtle differences in metals concentrations can be determined.

Nationally-certified per NELAP and internally-certified per ISO 17025 to perform EPA Method 1640, Brooks Applied Labs offers our clients a distinct level of experience performing this highly complex method. We can determine the following metals using Method 1640:

  • Antimony
  • Arsenic
  • Berillium
  • Cadmium
  • Cobalt
  • Copper
  • Chromium
  • Nickel
  • Lead
  • Selenium
  • Silver
  • Thallium
  • Vanadium
  • Zinc

In addition to the metals specified by the method, we have further developed the technique to include many more of the analytes often targeted in seawater projects. While the method was originally developed for ambient levels of metals in seawater, it has been increasingly used for monitoring metals concentrations in estuaries, effluent mixing zones, and for wastewater discharges from desalinization plants.

The sample collection, preservation, and handling requirements for EPA Method 1640 are very specific and consultation with one of our representatives is highly recommended prior to beginning a project.

Brooks Applied Labs has some of the lowest detection limits commercially available to our clients. View our MDL & MRL Table.