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As an analytical chemistry professor with extensive background and contribution to the field of environmental, clinical and forensic sciences, I will be pleased to accept prospective students into my research group, where one may tackle one of the challenging questions listed below:

I. Development and application of analytical methods for environmental essays.

After the definition of a specific (micro-) ecosystem of interest, the identification and quantification of its chemistry, particularly its anthropogenic substances are quite essential. This in many instances is the pre-requisite toward better understanding, monitoring and characterizing such ecosystem. Efforts will be made to adhere to EPA prescribed methods, namely EPA 500 and 600 series. Specifically, volatile, semi-volatile and chlorinated organic substances in a matrix of interest will be separated, identified and quantified.

There are, however, occasions where the analysis of a sample of interest may not be routine in nature; for example, extracts from living organisms. In such cases, one must devise a careful method by which the sample constituents could be identified.


Even though biosensors are not yet employed as the standard EPA prescribed methods, one could nonetheless, envisage the promising potential for their application as state-of-the art tools for real-time monitoring of environmentally important substances and metabolites. There are also other promising applications in fields like Forensics and QA/QC monitoring. A biosensor is defined as a molecular recognition component coupled with a transducer.

The bio-molecular component may include :

  • Enzyme
  • Antibody
  • Cellular component
  • Tissues
  • Micro-Organism

The transducer component may include:

  • Optical
    (An optical fiber connected to a spectroscope)
  • Termistor
    (For measuring heat exchanges associated with a (bio-) chemical reaction)
  • Piezo-electric
    (Microbalances to measure mass (ex-) changes associated with a selective reactions)
  • Electrochemical
    (To measure electron exchanges associated with a redox reaction)

Generally speaking, the specificity of a biological element when coupled with the molecular selectivity of a membrane will provide a highly sensitive optimum condition where sample pre-treatment or separation is not necessary. Our previous track record in the exciting field of biosensors will enable us to continue devising new sensors for novel applications. One could mention ease of operation, sensitivity, selectivity, stability, real-time capability, and cost effectiveness of biosensors as some of those advantages over classical methods.

III. Persistence, Bioaccumulation and Toxicity
        By David N. Rahni and John Morelli

According to Chemical Abstract Service, published by the American Chemical Society (ACS), there are currently over 17 million registered substances. That compares to over a million words in the entire English Language! This vast library of chemicals includes both naturally occurring and synthetically manufactured materials (1). The number of chemicals, produced in the US since the mid 70's, is over 70,000. Of these, 15,000 were manufactured in quantities with potential environmental impact (2). This resulted in 306 million tons of hazardous waste and 3.2 billion pounds of toxic chemicals (3,4). In light of such vast number of potential chemicals with future anthropogenic toxic output, a systematic method of ranking chemicals on their environmental impact and health risk is essential. The U.S. Environmental Protection Agency (EPA) is currently reviewing a software package to assist such a ranking.

Chemical Manufacturers Association has prioritized this challenge in a report entitled How Persistence, Toxicity, and Bioaccumulation (PTB) are Defined and Used in Chemical ranking System (CMA Report on PTB, March 24, 1995).

The EPA is committed to making pollution prevention the guiding principle of the Agency’s environmental efforts. The 1984 Amendments to the Resource Conservation and Recovery Act and the 1990 Pollution Prevention Act set in policy the preference for source reduction over waste management. The EPA administrator, Carol M. Browner, reaffirmed this commitment with the release of the "Waste Minimization National Plan" on November 18, 1994, which outlined the EPA’s major goals, objectives, and action items to pave the way toward national reductions in the generation of hazardous waste. Of importance here, is the goal to reduce, as a nation, the presence of the most persistent, bioaccumulative, and toxic constituents by 25 percent by the year 2000 and by 50 percent by the year 2005. While the EPA does not expect that each and every generator reduce PTB substances in hazardous waste to this degree, it is, nevertheless, likely that at some future juncture the pressure to reduce will be inevitable. This pressure will most likely take the form of international, national, and local legislation, monitoring, and compliance. An example of the complexity of issues and challenges facing the global business community was the extensive deliberation on limiting Green House gases at the Conference on Global Warming in Kyoto, Japan in December 1997.

Beyond the legislative and regulatory pressure, there are market driven factors to induce voluntary compliance with adopted standards. An example of recent voluntary compliance with adopted standards is the recent worldwide success and acceptance of ISO 9000 series that deal with quality assurance, and quality control systems management since 1987. Correspondingly, a new series of environmentally related standards for industry are the ISO 14,000 series. In October of 1996, the International Standard Organization released a set of international standards for environmental management called ISO 14000. These standards are deemed to revolutionize the way both corporations and government approach environmental issues and natural resources consummations (e.g., energy and raw materials). Furthermore, such standards will provide a common language for environmental and natural resource management, thereby establishing a framework for third party regulation of environmental management systems, and helping industry satisfy the demands of consumers and regulatory agencies for corporate environmental accountability. ISO 14000 series can only be applied in a truly integrated multi-disciplinary team approach comprised of scientists, engineers, plant managers, legal, regulatory safety and accounting staff to name a few.


EPA outlines the objectives of the Waste Minimization National Plan (5) as follows:

To reduce, as a nation, the presence of the most persistent, bioaccumulative, and toxic constituents by 25% by the year 2000 and by 50% by the year 2005.

To avoid transferring these constituents across environmental media.

To ensure that these constituents are reduced at their source whenever possible, or, when not possible, that they are re-cycled in an environmentally sound manner

Such targets are national in nature, in that each corporation would define its own baseline, and demonstrate improving trends to contribute toward national targets on a voluntary basis at this time. The EPA guidelines set objectives as follows:
Develop a framework for setting national priorities; develop a flexible screening tool for identifying priorities at individual facilities; identify constituents of concern.

EPA currently offers a beta-test version of a software package which will prioritize chemicals according to their persistence, bioaccumulation, toxicity, and quantity. We will evaluate this package for those classes of chemicals that are of the highest priority by the Grantor for specific purpose (6).

The chemical stability of PCBs is paralleled by their environmental stability and potential for environmental transport and it is evident from analytical surveys that PCBs are the most ubiquitous chemical pollutant in the global ecosystem (7). Several reports suggest that the toxicity of PCBs is structure dependent (8). A global model to track the distribution of PTBs (9) using chlorophenolic compounds were chosen to illustrate the transport of PTBs . The model is applicable to any other similar substituents. It is generally accepted that there are three basic components of a hazard assessment of organic compounds discharged into aquatic environment persistence to both abiotic and biotic degradation; partition from the aquatic phase into the sediment phase and into biota, and toxicity to biota (10).

The currently practiced regulation is that a newly manufactured substance can be marketed and released without any initial approval. In the United States, for instance, if the EPA can not determine an industrial chemical’s suitability for the market within 90 days of submission, that chemical is automatically approved under the Toxic Substance Control Act. There is no minimum data requirement. Given the half a million dollars expense, at a minimum, and the two to five years required to test a single chemical for long-term effects, such testing is inevitably limited (10). We however, predict that with rapid advances in computer modeling, more versatile testing methodology, and the public pressure, that such exhaustive testing may be required soon as a pre-requisite toward approval.

This does not even take into consideration the synergistic effect of chemicals on human health and ecological status. For instance, John MacLachlan of Tulane-Xavier Center for Biomedical Research and his colleagues recently showed that two weakly estrogenic chemicals, when used in combination, were up to 1,600 times more potent than when each was used alone. And pesticides such as malathion and other organophosphates, when administered simultaneously are up to 50 times more toxic. In light of the rather large number of chemicals used in society today, it is almost impossible to test all of the combinations to which we are routinely exposed. To test the 1,000 new chemicals released each year just in the possible combination of three, would require more than 166 million tests, each for a two year study, to assess the long-term effects such as cancer and endocrine disruption. Yet, in the US only 500 tests are undertaken each year, thereby leaving more than166 million tests left for the following year! Automated Combinatorial techniques may revolutionize this lag time (11)


A model for screening, ranking and scoring chemicals by potential human and environmental impacts have been reported (12). Among all substances, perhaps, PCBs, Dioxins, and organophaosphates are the most extensively studied ones in terms of toxicokinetics, and PTBs (13, 14)

Currently, bioaccumulation is screened as a measure of the lipophilicity of a compound.
Lipophilicity is the tendency of a substance to be attracted primarily by a non-polar, usually
organic solvents, in contrast to hydrophilic substances, which are attracted by polar solvents such as water. As a measurement unit of lipophilicity, most often the partition coefficient between water and n-octanol is taken and designated as Pow or Kow (or Ko/w). The relationship between the steady state bioconcentration factor (BCFs) and Kow has been found many times to follow a logarithmic regression of the form:

Log BCFs=aX log Kow+ b

Work by Bronson et al. in 1994 outline two step strategy for assessing the ecotoxicological aspects of complex wastewater from a chemical-pharmaceutical plant. All substances were classified on the basis of environmental effects using acute toxicity, biodegradation, and bioaccumulation criteria. The first step is to utilize a chemical-oriented strategy. This strategy utilizes data on discharged amounts of material from the plant and ecotoxicological data for each compound. Discharge amounts can be estimated using mass balance calculations or through actual analytical measurements of water phase effluents. In this phase, ecotoxicological data for each compound is available. For water phase effluents with less defined chemical characterization or ecotoxicological data, an extensive characterization program, including chemical analyses, acute toxicity testing, and ecotoxicological parameterization, is required to assess environmental risk. Bronson et al. showed that while toxicity and bioaccumulating organic compounds were very low, and easily degraded by activated sludge, the presence of individual chemicals with high toxicity at low concentrations had measurable unfavorable effects. The end result is that standard bulk chemical (AOX, EOX, DOC, TOC, etc.) and biological testing alone cannot accurately predict bioaccumulation, toxicity, and persistence of plant effluents. A screening of water effluents for bioactivity/toxicity with these bulk tests followed by a characterization program using mainly available ecotoxicological data for chemicals discharged to wastewater when available or a limited set of ecotoxicological test when such data is absent is necessary.

The foundation of the persistence, toxicity, bioaccumulation data is analytical measurements. Myriad methods for determining specific levels of compounds in a variety of media including soil, animal and plant tissues must be applied. Much of this might be presented in the literature; therefore, a thorough literature search will be conducted to identify such methods. For materials and matrices that are not represented in the literature model methodology would be developed or proposed. For one system of Grantor’s choice this methodology would be demonstrated.

Chemical Project

a. Persistence & Bioaccumulation Issues

b. Analytical Chemistry and Method Improvements

c. Review of current data on specific manufactured Chemicals of interest

Biology Causation Section

A review on Human data, Animal Data, and Ecosystem Data
On those specific class of up to four chemicals specified by the grantor, and with emphases on aquatic and microbial ecology will be prepared.


EPA in concert with other Federal and State Agencies have enacted a series of Legislation
On National Waste Minimization Strategies, with Persistence, Bioaccumulation and Toxicity as their main objects.

Certain steps to standardize chemical sale internationally have already been taken. Prior Informed Consent (PIC) Treaty, a proposed Convention that would require exporting countries and corporations to provide information on whether the chemical that they are exporting is restricted or banned nationally, is expected to be considered by early 1998(11).

Pace University’s LL.M. Environmental Law program is consistently recognized by external peers such as US News &World Report as being among the top three in the nation.

One of the Principal Investigator of this proposal, David N. Rahni has taught in this program, he is currently serving students from this program, and he has a close on-going collaborative relationship with several colleagues from the Environmental Law Faculty.

Law School Dean, Richard Ottinger, a past eight times US Congressman who was instrumental in drafting and legislating most of the Federal laws on the environment in the 60’s and the 70’s has been a close colleague. Dive Sie, the Guru of environmentalism is a Professor-in-Residence at the Law School as well. One of our Law colleagues was representing Texaco in the Valdez, Alaska oil accident.

Professor Nicholas Robinson is an internationally renowned Environmental Law expert who is currently leading many activities in the former Soviet Union and East European Countries. Such efforts will ultimately lead to environmental legislation and regulation in these countries.

We will draw upon such intellectual resources, in particular that of Professor Robinson to research, investigate, and prepare an annual report on EPA National Waste Minimization Act, its trends, and its pertinent regulations and requirements. Particular emphasis will be placed on those up to four specific classes of compounds of interest to the Grantor.


1. Chemical &Engineering News, October 5, 1997.

2. U.S. Congress. 1995. Screening and testing chemicals in commerce. OTA-BP-ENV-166. Background Paper. Office of Technology Assessment, Washington, DC.

3. 1991 Biennial Report Data, US EPA

4. 1992 Toxic Release Inventory; Public Data Release," US EPA, EPA 745-R-94-001, April 1994.

5. The Waste Minimization National Plan, EPA, November 16, 1994.

6.   http://www.epa.gov/epaoswer/hazwaste/minimize

FTP: ftp.epa.gov
Login: anonymous
Password: Your Internet address

7. S. Safe, L. Safe, M. Mullin Polychlorinated Biphenyls: Congener-Specific Analysis of a Commercial Mixture and a Human Milk Extract. J. Agr. Food Chem. 1985, 33, 24-29.

8. Poland and Knutson, et al 1977-85)

9. F. Wania and D. Mackay, Tracking the Distribution of Persistent Organic Pollutants Env. Sci and Tech., Vol 30, No. 9, 390A-396A,1996

10. Neilson, A.S. Allard, P-A. Hyanning, M. Reberger Env. Sci. Technol. Vol. 28, No. 6, 278A-287A,1994

11. J. D. Mitchell, Nowhere to hide: The global spread of high-risk synthetic chemicals, World Watch Institute (1997)

12. M.B. Swanson, G.A. Davis, L.E.Kincaid, Environmental Toxicology and Chemistry, Vol. 16, No. 2, pp. 372-383, 1997

13. M. Van den Berg, J. de Jongh, H. Poiger, J. R. Olson Critical Reviews in Toxicology, 24(1):1-74 (1994)

14. V. McFarland, J.U. Clarke, A. B. Gibson Changing Concept and Improved Methods for Evaluating the importance of PCBs and Dredged sediments contaminants, Report D-86-5, US Dept. Army, US Corp of Engineer, 1986

IV.ISO 14,000

In response to above Plan, the Chemical Manufacturers Association (CMA) is in the process of developing a comprehensive strategy of programs and tools that define a risk based approach for the quntitation of persistence, toxicity and bioaccumulation of chemicals manufactured. The current accepted method of extraction followed by spectroscopic method is inadequate at best. We plan to understand the current methodology. We then plan to devise chromatographic based mass spectrometric methods to assess PTB. Such methods when fully developed must replace the current insensitive methods.

This is an interdisciplinary approach to manufacturing, where environmental and natural resource conservation objectives will be met while economic development considerations are still satisfied. Even though based on scientific and technological breakthroughs of the 21st century, it involves environmental accounting and reporting, environmental law, regulation, monitoring and compliance, environmental policy, etc.

V.  Sustainable Development, Intergenerational Equity and Internationalization as a vehicle for moving the concept forward.

VI. Other Scholarly Activities

  • Synthesis and Conformation of Chiral Seven- and Eight-Membered Germanium, Phosphorous Heterocyclics;
  • Nano-Engineering and Electrodeposition of Compositionally Modulated Alloys;
  • Process Analytical Chemistry and Manufacturing Engineering.
  • Environmental and clinical forensics
Mathieu Orfila (1787-1853), the Founder of Modern Forensic Toxicology

Paul L. Kirk (1902-1970), the American Founder of Forensic Science



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By David N. Rahni

The science of analytical chemistry has undergone through tremendous growth within the past decade. However, advanced instrumentation and detection technologies have not been fully integrated into the forensic science. In particular, portable detection technologies applicable to environmental forensics, will be a major focus in the next decade.


  • Documentation
  • Sampling and its stabilization
  • Transportation
  • Storage
  • Sample reconstitution
  • Statistical and Probability tools


  • Calibration (Instrument, methodology)
  • Method development, validation, and verification
  • Parallel, independent analysis and correlation (e.g., RFLP, STR)
  • Computation, calculation, biometrics, chemometric, statistically and probabilistically based error analysis,  and data interpolation
  • Exploration, Recognition, and Promotion of the Latest Methodologies and Technologies
  • Report
  • Proficiency
  • Standardization (e.g., ISO 9000 and 14,000 series, ASTM, etc.)
  • Accreditation (Am. Soc. Crime Lab. Dir./Lab. Accred. Board)


  • Appropriate pedagogical approach to training professionals with and, or without science backgrounds
  • Lab and field methods inauguration
  • State and local lab assistance implementation
  • 23+ International lab installations
  • DNA typing
  • Collection of evidence
  • On site field assessment
  • Modes of training: on-site, off-site, CD-ROM, Distance learning technology (e.g., Internet as a medium,) synchronous and, or asynchronous video interactive technology, simulations, tutorials.
  • LEGAL: Expert witness training at the interface of science and law; Educating judges, prosecutors, attorneys, jurors, and the public at-large.


  • Pro-active and pre-emptive detection and deterrence R&D
  • Portable instrumentation technologies for Environmental Forensics
  • MSDNA (4,000-20,000m/z)
  • Field detection Sensor technology, and new instrumentation and methodology
  • Cell separation, DNA processing and hybridization, based on dielectric variations on a chip.
  • Chip-based degenerate oligonucleotide primed polymerase chair reaction (DOP-PCR) for 250 bp.
  • Standardization of Forensic Science Assays, analyses, and reporting
  • DNA typing library databank (e.g., CODIS, DRUGFIRE)
  • Thermal cycler DNA preparation and other methods (e.g., PCR amplification, HPLC-Fluorescence, HPLC-Electrospray-MS/MS used for drugs in hair)
  • Combinatorial chemistry and analytical automation (100,000 assays per day soon)
  • High Performance Iso-electric Focusing Capillary Electrophoresis, & capillary electro-chromatography (CEC).
  • Mass Spectrometry (e.g. MALDI-TOF-MS, or Electrospray-MS)
  • Refining and streamlining DNA profiling
  • Imaging and Surface Characterization Technology (SEM, STM, TEM, X-ray Fluorescence, Optical and Fluorescence Microscopy, SFM)
  • Capillary Electrophoresis with laser induced fluorescence down to attomole, i.e. single cell detection.
  • Identification and adoption of the latest instrumentation for forensic science applications.
  • The April 29 signature by the US on Chemical Weapon Convention, will lead to tremendous need in development of chemical and biological arms detection and assessment technologies.
  • Environmental Forensics.


  • Prepared to serve as a liaison on public issues at the pleasure of the Lab. & Training (TBD) Divisional Directors.
  • Communication with other government agencies (NSF, NIH, DOD, DOE, ATF, NIST, DEA, Armed Forces, etc) to define and prioritize Forensic Science R&D through grants and other incentives to academia, government labs, and corporate world.
  • Communication with corporate world in promoting the development and offering of instrumentation and methodology to the field of forensic science, an integral support component of crime prevention and law enforcement.


  • Attaining the plateau of learning curve in context in a reasonable time frame
  • Utilizing human relations principle with mutual respect, interpersonal skills, communicative skills, multi-tasking abilities, meeting deadlines, responsibility and accountability concept, professional integrity to further enhance the fulfillment of the Mission.
  • Recognizing the best talents and potentials in colleagues and peers, and then support them best in realizing the team’s goals.
  • Utilizing one’s interdisciplinary academic, teaching, and research track records in a wide array of natural, physical, and engineering fields.
  • Build further on one’s administrative and service leadership track records.
  • Promoting of, and providing leadership to Professional Societies of Forensic Chemistry and Science.
  • Contributing on Public Relations, image, standardization, certifications, and continuing education.
  • Articulating and facilitating extramural R&D and technology transfer as applied to forensic science.
  • Contributing toward accreditation, and methods and protocol standardization.
  • Contributing toward physical plant construction, renovation, and procurement and maintenance of analytical instrumentation.
  • Providing leadership in further enhancing Symposia proceedings in forensic science, particularly environmental forensics.
  • Contributing scholarly manuscripts, reviews and communications internally and when appropriately authorized to professional journals and the scientific communities.

Restriction Fragment Length Polymerization (RFLP)

Technical Working Group for DNA Analysis Methods (TWGDAM)
The basic analytical procedure involves the following steps:

  1. Digestion of extracted DNA with restriction enzyme endonuclease HaeIII.
  2. Amplification of DNA
  3. Electrophoretic separation of the resulting bands with agarose slab gel.
  4. Southern blot immobilization of separate fragments onto nylon mesh.
  5. Hybridization with radiolabeled specific sequences of DNA (probes).
  6. Autoradiographic visualization of labeled DNA fragments hybridized to their specific complements (foci).
  7. Determination of relative position of calibration, i.e., sizing ladder.
  8. Sample bands on the autoradiogram.
  9. Calculation of the apparent molecular weights as expressed as number of base pairs (bp).

Source: JAMES L. MUDD et al Anal Chem. 1997, 69, 1882-1892, and references therein.

The content of this website is accurate to the best of our knowledge,and will be updated periodically. Materials herein may be reproduced with prior authorization from D.N.Rahni.