Development and Testing of Environmental Instrumentation

NSF EPSCoR COSS Research Center

 

 

COSS (the Center for Optical Sensors and Spectroscopies, http://www.coss.phy.uab.edu/) is a multi-institutional research center located in the Physics Department at the University of Alabama at Birmingham and is supported by NSF EPSCoR. COSS is a group of researchers and facilities from UAB, UA, and UAH. It has two major groups: a) the environmental group headed by Robert Pitt of the Department of Civil, Construction, and Environmental Engineering at UA; b) the laser, sensor, and spectroscopy group headed by Chris Lawson (UAB) and Sergey Mirov (UAB) and Richard Fork (UAH).  The mission of COSS is to promote optical sensing and spectroscopy research on environmental, biomedical, and national security issues among the member universities, government and industrial laboratories. One of the primary objectives of COSS is to develop novel optical sensing techniques for detection of hazardous agents, as well as techniques to protect sensors from terrorism-related threats.

 

The main objectives of the environmental research group at UA are:

- to identify toxic and hazardous materials and their sampling and measurement methods. with emphasis on heavy metals and organic toxicants,

- to use predictive methods to identify the needed measurement levels for extremely hazardous materials for a variety of typical release conditions,

- to quantify performance levels for newly developed instruments for different applications,

- to verify the performance of new instrumentation and supply quality assurance and quality control, and

- to conduct field investigations to quantify fate mechanisms of released toxic and hazardous materials. 

 

After reviewing several hundred case histories involving accidental losses of toxic and hazardous materials and other sources, the research team has identified herbicides, pesticides, and PAHs (polycyclic aromatic hydrocarbons) of interest in relationship to environmental monitoring needs, transportation accident hazardous material releases, Water Sentinel water system safety monitoring, and losses during large-scale natural disasters. In order to determine the forms of these compounds that should be monitored, the research team modeled the fate of these compounds to identify the environmental characteristics and chemical factors that may affect their fate when they released into the environment. As part of this study, the team used fugacity calculations to quantify the amount of contaminates partitioned into air, water and solid components of the environment. Factorial design calculations were used to estimate the effects of different factors namely, concentration of contaminant, volume of solids, and organic fraction of solid components on the partitioning of the contaminants. Factorial calculations were used to find the effects of the factors, both individually and their interactions, on their fates. Results clearly showed that the factors of most significance influencing the partitioning of the contaminants onto suspended solids were the concentration of the contaminant, the concentration of suspended solids, and their interaction.

 

The majority of many of these compounds are strongly associated with the particulate matter in the water. Traditional extraction methods needed before sample analysis [solid-phase extraction (SPE) (EPA method 3535, SW-846); continuous extraction of liquid samples (EPA method 3520);  Soxhlet (EPA method 3540); automatic Soxhlet method (EPA method 3550, SW-848)] are all problematic in that some have great interferences with the solids in the water, take long times, and require large quantities of dangerous solvents. New procedures that can directly measure these organic compounds at low concentrations would be a great help in rapid response to accidental releases of these compounds. The laser methods being developed by COSS are intended to overcome these problems.

 

After reviewing the different procedures for contaminant preparation and analyses, and based on estimation calculations performed by the research team, the team decided to modify and test a newly developed extraction procedure for the QA/QC analyses. In selecting, modifying, and testing this procedure, importance was given to factors which produce the most reliable results considering the wide range of dissolved and particulate concentrations of the contaminants and relatively rapid methods that use minimal solvents. The selected analytical steps are as follows: filtration of sample to separate the particulates from the dissolved fraction, Solid Phase Extraction of the dissolved fraction, and thermal desorption for the extraction of the solids materials captured on the filter.. 

 

 

 

 

Schematic of packed desorption tube (Source: SIS product manual)

 

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Model Predicted PAH partition values

PAH

% Partition into

Water

Suspended Solids

Sediment

Naphthalene

93

0

7

Anthracene

59

1

40

Fluorene

74

1

26

Fluoranthene

35

2

63

Pyrene

35

2

63

Chrysene

9

3

88

Benzo(a)anthracene

5

3

92

Benzo(b)fluoranthene

4

3

94

Dibenzo(a,h)anthracene

1

3

96

Indeno(1,2,3-cd)pyrene

1

3

96

Benzo(ghi)perylene

1

3

96

 

 

24 factorial design (Box, et al 1978)

 

 

 

 

 

 

 

 

 

 

 

 

Probability plot to identify important factors affecting anthracene partition into water and suspended sediment phases respectively

 

 

Desorption time versus peak areas for pyrene and benzo(ghi)perylene respectively

 

 

SIS AutoDesorbTM unit

 

 

Stainless steel Thermal Desorption tubes used for loading samples

 

 

Tubes and needles conditioning oven

 

 

Schematic of organic analysis using GC

 

 

Sampling at Lake Tuscaloosa

 

Sampling point on concrete channel along Cribb’s Mill Creek, Tuscaloosa

 

Sediment sampling along the Carroll’s Creek, Northport

 

 

Mr. Jejal Bathi operating TD/GC/MS in the laboratory

 

 

Publications related to this research work:

 

“Associations of Polycyclic Aromatic Hydrocarbons (PAHs) with Particulates in the Environment”, Dissertation proposal of Jejal  Reddy Bathi.

 

Bathi, J.R., Pitt. R., Findlay. R., Clark, S. E., Mirov. S. “Distribution of Polycyclic  Aromatic Hydrocarbons among Sediment Size Fractions Determined by Thermal Desorption Gas Chromatography Mass Spectrometry.” An abstract has been submitted for WEFTEC, October 2008, Chicago, IL.

 

Bathi, J.R., Pitt. R., Findlay. R., Clark, S. E., Mirov. S. “Associations of PAHs with Size  Fractionated Sediment Particles.” An abstract has been submitted for WEFTEC, October 2008, Chicago, IL.  

 

Bathi, J. R., Pitt. R.  “Analyses of PAHs in Urban Stormwater Particulates.” An abstract has been accepted for 11th International Conference on Urban Drainage, 11ICUD. Edinburgh, Scotland, UK, August, September 2008.

 

Bathi, J. R., Pitt. R., Mirov. S. “Understanding the Fates of PAHs using Thermal Desorption as an Analytical Tool.” Poster presented at NSF EPSCoR National Conference, Hawaii, November 6-9, 2007.

 

Clark, S. E., Siu, C. Y. S., Roenning, C. D., Treese, D. P., Pitt. R., Bathi, J. R. “Automatic Sampler Efficiency for Stormwater Solids”. Presented at the 2007 Pennsylvania Stormwater Management Symposium. Villanova, PA. October 17-18, 2007.

 

Pitt, R., Bathi. J, C. Greer, K. Boykin, R. Rogers, "Multi-Disciplinary Collaborative Sustainable Environmental Land-Related Research at the University of Alabama".  Presented at the 2007 Gulf Coast Forum: "Gulf States Alliance: Network Science and Recovery", Biloxi, Mississippi, August 20-23, 2007.

 

Bathi, J. R., Pitt. R. “Fates of Polycyclic Aromatic Hydrocarbons (PAHs) Affect Treatability.”  World Environmental & Water Resources Congress 2007. ASCE - EWRI. Tampa, FL. May 15 – 19, 2007.

 

Bathi, J. R., Pitt. R. “Fates of Emerging Contaminants in Stormwater: A case Study of Polycyclic Aromatic Hydrocarbons (PAHs).” Alabama’s Water Environment Association 2007 Technical Conference. Orange Beach, AL, April 15 – 18, 2007.

 

Bathi, J.R., Pitt. R., Findlay. R. “Standardization of Thermal Desorption GC/MS Analysis for Polycyclic Aromatic Hydrocarbons and Comparison of Recoveries for Two Different Sample Matrices.” Annual Mississippi Water Resources Conference Jackson, Mississippi, April 2007.

 

Bathi, J.R., Pitt,R., “Sample Preparation for GC/MS Analysis; To Study the   Partition of Organic Contaminants in Water.” A poster was presented at NSF EPSCoR Annual meeting, February 2006, University of Tuskegee, Tuskegee.