USGS-NWQL: I-1472-95: Aluminum and Boron, dissolved, in water by ICP-AES

Summary
Analytes
Revision
Data and Sites

Official Method Name

Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory-Determination of Dissolved Aluminum and Boron in Water by Inductively Coupled Plasma - Atomic Emission Spectrometry

Current Revision

1995

Media

WATER

Instrumentation

Inductively Coupled Plasma - Atomic Emission Spectroscopy

Method Subcategory

Inorganic

Method Source

USGS-NWQL

Citation

Struzeski, T.M., DeGiacomo, W.J., and Zayhowski, E.J., 1996, Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory -- Determination of dissloved aluminum and boron in water by inductively compled plasma-atomic emission spectrometry: U.S. Geological Survey Open-File Report 96-149.

Brief Method Summary

Dissolved aluminum and boron are determined simultaneously on a single sample by using an inductively coupled plasma emission spectrometer. Sample solution is pumped into a crossflow pneumatic nebulizer that produces a liquid aerosol. This aerosol is subsequently transported by argon gas through a spray chamber and torch assembly into an inductively coupled plasma source where the aerosol is desolvated and atomized, and the resultant atoms or ions are excited. The emission, which results as excited state atoms or excited state ions relax to their ground state, is measured and the signal integrated. Each result is determined on the basis of the mean of three replicate integrations. The results then are converted to concentration.

NOTE: This method is a supplement to I-1472-87.

Scope and Application

This method is suitable for the single-element or multielement determination of dissolved aluminum and boron in precipitation samples and surface-, ground-, and drinking-water samples that have a measured specific conductance of less than 2,000 uS/cm at 25 deg. C. Samples that have a measured specific conductance greater than or equal to 2,000 uS/cm may be diluted by the minimum factor possible to adjust the sample to the specified limit; however, the method reporting limit (MRL) of all reported analytes will increase by the factor of dilution.

Applicable Concentration Range

Al: 5.0-100,000; B: 4.0-10,000

Interferences

Iron concentrations at 100,000 ug/L or above cause false positive readings of approximately 243 ug/L for Al and 36 ug/L for B. Samples containing high dissolved solids can exhibit unidentified interference effects. These effects can be minimized by analyzing only samples that have a measured specific conductance less than 2,000 uS/cm at 25 deg. C (Fishman, 1993).

Quality Control Requirements

Method blanks, reagent spikes, surrogate spikes, certified reference material samples, continuing calibration verification standards, field blanks, field replicates, matrix spikes and matrix spike duplicates, quarterly control samples and Branch of Quality Assurance samples are analyzed. Data from these are compiled to continually monitor the QA/QC of the analysis. Each analyst must undergo technical and ethics training, perform an initial demonstration of capability, and annually demonstrate continuing capability on an analysis. Additional QA/QC practices may be added.

Sample Handling

Description: 250 mL Polyethylene bottle, acid-rinsed.
Treatment and Preservation: Filter through 0.45-um filter, use filtered sample to rinse containers and acidify sample with nitric acid (HNO3) to pH < 2.

Maximum Holding Time

180 days from sampling

Relative Cost

Less than $50

Sample Preparation Methods

This method has 2 analytes associated with it.

Analyte	Detection Level	Bias	Precision	Pct False Positive	Pct False Negative	Spiking Level
Aluminum(7429-90-5) Al Aluminium Aluminum Aluminum (fume or dust) Aluminum powder	5.000 ug/L	N/A	N/A			54.10 ug/L
Boron(7440-42-8) B Boron Boron (Boron and Borates only)	4.000 ug/L	N/A	N/A			54.10 ug/L

Precision Descriptor Notes:	The accuracy and precision of the ICP?AES method were determined in two studies using USGS Standard Reference Water Samples (SRWS's). First, in a short-term study, SRWS's were analyzed for aluminum and boron on seven different days using the same instrument and operator. Second, long-term accuracy and precision were determined from historical on-line quality-control data. Multiple SRWS's at various concentrations of analyte were analyzed over a 9-month period by a single operator (except for boron in SRWS T-113, which was analyzed over a 4-month period). The number of replicates used in this study varies from 150 to 550. Results show that dissolved aluminum determinations by the proposed method were in agreement with the interlaboratory most probable values (MPV's) for the SRWS's. The study also indicated that not only is the precision of the ICP?AES method well within the limits established using the interlaboratory F-pseudosigma, but it is also generally superior to that of the present direct current plasma?atomic emission spectrometry (DCP?AES) method in Fishman (1993).
Detection Level Note:	The National Water Quality Laboratory (NWQL) has addressed the limitations of the USEPA Method Detection Limit (MDL) procedure outlined in 40 CFR 136, App. B. The NWQL recommends an alternative for determining MDL?s and reporting limits. It?s called the Long-Term Method Detection Limit (LT-MDL). The LT-MDL is designed to catch greater method variability because it requires a larger number of replicate spike samples ? at least 24 per year, data be gathered over a longer period of time ? 6 to 12 months, and incorporates more measurement variability inherent in routine sample analysis such as multiple instruments, operators, calibrations, blank contributions and sample preparation events. The LT-MDL is based upon key assumptions underlying the USEPA procedure. These are a normal frequency distribution, constant standard deviation, and best-case detection. LT-MDL?s like MDL?s are determined using spikes in a clean matrix. See USGS Open File Report 99-193 regarding the LT-MDL.

Precision Descriptor Notes:

The accuracy and precision of the ICP?AES method were determined in two studies using USGS Standard Reference Water Samples (SRWS's). First, in a short-term study, SRWS's were analyzed for aluminum and boron on seven different days using the same instrument and operator. Second, long-term accuracy and precision were determined from historical on-line quality-control data. Multiple SRWS's at various concentrations of analyte were analyzed over a 9-month period by a single operator (except for boron in SRWS T-113, which was analyzed over a 4-month period). The number of replicates used in this study varies from 150 to 550. Results show that dissolved aluminum determinations by the proposed method were in agreement with the interlaboratory most probable values (MPV's) for the SRWS's. The study also indicated that not only is the precision of the ICP?AES method well within the limits established using the interlaboratory F-pseudosigma, but it is also generally superior to that of the present direct current plasma?atomic emission spectrometry (DCP?AES) method in Fishman (1993).

Detection Level Note:

The National Water Quality Laboratory (NWQL) has addressed the limitations of the USEPA Method Detection Limit (MDL) procedure outlined in 40 CFR 136, App. B. The NWQL recommends an alternative for determining MDL?s and reporting limits. It?s called the Long-Term Method Detection Limit (LT-MDL). The LT-MDL is designed to catch greater method variability because it requires a larger number of replicate spike samples ? at least 24 per year, data be gathered over a longer period of time ? 6 to 12 months, and incorporates more measurement variability inherent in routine sample analysis such as multiple instruments, operators, calibrations, blank contributions and sample preparation events. The LT-MDL is based upon key assumptions underlying the USEPA procedure. These are a normal frequency distribution, constant standard deviation, and best-case detection. LT-MDL?s like MDL?s are determined using spikes in a clean matrix. See USGS Open File Report 99-193 regarding the LT-MDL.

Revision	PDF/Link
1995

The Water Quality Portal contains sample results from sites that use this method.

Download WQP data

Select data:

Sites only
Sample results only

File format:

Comma-separated
Tab-separated
MS Excel 2007+

Sites where this method was used

Loading Sites ...

USGS-NWQL: I-1472-95: Aluminum and Boron, dissolved, in water by ICP-AES

WHO WE ARE

LEGAL