Episode 1 of The Lab Report: Water Contamination Analysis Using ICP-OES (US EPA Method 200.7)

Summary

In this lab report, Paul Krampitz explores the analysis of water using an ICP plasma spectrometer, revealing the presence of various elements. The process involves heating water with an argon plasma to convert it into a gaseous mixture, which is then analyzed for elemental composition. The ICP system's high resolution and multicomponent spectral fitting technique address complex spectral interferences and background corrections. The technology is highlighted for its efficiency in environmental laboratories, offering a significant productivity boost and adherence to EPA standards for water and wastewater analysis.

Takeaways

• 🔬 The video discusses the analysis of water using an ICP plasma spectrometer to determine the presence of different elements.
• 🔥 A heat source is required for water analysis, with the script mentioning butane lighters and commercial flames like welding torches, but emphasizing the need for even hotter sources like argon plasma.
• 🌌 Argon plasma is used in the Optima ICP system, which is a hot, ionized gas with electrons, maintained by an induced magnetic field, capable of reaching temperatures hotter than the Sun's surface.
• 💧 When water is introduced into the plasma, it quickly converts from liquid to gas, releasing a gaseous mixture of elements originally in the water sample.
• 🌌 The electrons in the elements' orbitals get excited by the plasma and emit photons when they return to lower energy levels, which are then separated by wavelength in the ICP spectrometer.
• 📊 The ICP system correlates the signal from the emitted photons to a known calibration standard to quantify the metals present in the water.
• 🔄 The script mentions the importance of rinsing out tubing between samples to avoid contamination, and the use of a fast valve to reduce the rinse time significantly.
• ⏱️ The ESI fast system mentioned in the script can halve the sample-to-sample time, which is beneficial for environmental laboratories that bill per sample.
• 🧬 The complexity of the spectrum when analyzing multiple elements is highlighted, with the potential for emission lines to overlap and interfere with the analytes of interest.
• 🛠️ The Optima system is noted for having the best resolution for a simultaneous ICP system and employs a technique called multicomponent spectral fitting (MSF) to handle complex backgrounds and spectral interferences.
• 🏥 MSF is an EPA-approved method that models noise components and increases detection limits, making ICP an excellent technique for analyzing water and wastewater according to EPA 200.71222 standards.

Q & A

What causes the characteristic blue color when copper is in solution?

Copper in solution has a characteristic blue color because it absorbs most of the red portion of the spectrum, leaving the blue portion to be seen.

What is an ICP plasma spectrometer and how is it used in water analysis?

An ICP plasma spectrometer is an analytical instrument that uses a hot ionized Argon plasma to convert liquid water samples into a gaseous mixture of elements. It then measures the wavelengths of light emitted by these elements to determine their concentrations in the water.

Why is a heat source needed for the analysis of water using an ICP plasma spectrometer?

A heat source is needed to create a plasma, which is a hot ionized gas that can break down water into its constituent elements. This process allows for the analysis of these elements' concentrations in the water sample.

What is the temperature of the plasma used in the Optima ICP system?

The plasma used in the Optima ICP system reaches temperatures of 10,000 degrees Kelvin or hotter, which is hotter than the surface temperature of the Sun.

How does the ICP system handle the complex spectrum of elements in water samples?

The ICP system uses a technique called multicomponent spectral fitting (MSF), which is a deconvolution technique combined with CMAN filtering to handle complex backgrounds and spectral interferences.

What is the significance of the fast valve system used in the ICP auto sampler?

The fast valve system in the ICP auto sampler reduces the rinse time for the tubing from about 90 seconds to 7 to 10 seconds, which significantly improves productivity, especially for environmental laboratories.

How does the ICP system separate the emitted photons from the elements in the plasma?

The ICP system separates the emitted photons by their wavelength using optics inside the instrument, which then correlates the signal to a known calibration standard or concentration.

What is the EPA approved method for analyzing complex matrices in water samples?

The EPA approved method for analyzing complex matrices in water samples is multicomponent spectral fitting (MSF), which is used to handle complex backgrounds and spectral interferences.

What are the benefits of using an ICP system for water and wastewater analysis?

ICP systems offer excellent resolution, handle complex spectra, and provide lower detection limits. They are also in full compliance with EPA 200.71222, making them an excellent choice for water and wastewater analysis.

How does the ICP system improve the analysis of drinking water and waste?

The ICP system simplifies the analysis of drinking water and waste by conforming to EPA 200.71222, which includes all necessary lines, QC checks, and calibration standards.