Deborah A. Grimm

Pharmaceuticals and personal care products (PPCPs) in surface and treated waters of Louisiana, USA and Ontario, Canada

A newly developed analytical method was used to measure concentrations of nine pharmaceuticals and personal care products (PPCPs) in samples from two surface water bodies, a sewage treatment plant effluent and various stages of a drinking water treatment plant in Louisiana, USA, and from one surface water body, a drinking water treatment plant and a pilot plant in Ontario, Canada. The analytical method provides for simultaneous extraction and quantification of the following broad range of PPCPs and endocrine-disrupting chemicals: naproxen; ibuprofen; estrone; 17beta-estradiol; bisphenol A; clorophene; triclosan; fluoxetine; and clofibric acid. Naproxen was detected in Louisiana sewage treatment plant effluent at 81-106 ng/l and Louisiana and Ontario surface waters at 22-107 ng/l. Triclosan was detected in Louisiana sewage treatment plant effluent at 10-21 ng/l. Of the three surface waters sampled, clofibric acid was detected in Detroit River water at 103 ng/l, but not in Mississippi River or Lake Pontchartrain waters. None of the other target analytes were detected above their method detection limits. Based on results at various stages of treatment, conventional drinking-water treatment processes (coagulation, flocculation and sedimentation) plus continuous addition of powdered activated carbon at a dosage of 2 mg/l did not remove naproxen from Mississippi River waters. However, chlorination, ozonation and dual media filtration processes reduced the concentration of naproxen below detection in Mississippi River and Detroit River waters and reduced clofibric acid in Detroit River waters. Results of this study demonstrate that existing water treatment technologies can effectively remove certain PPCPs. In addition, our study demonstrates the importance of obtaining data on removal mechanisms and byproducts associated with PPCPs and other endocrine-disrupting chemicals in drinking water and sewage treatment processes.

Occurrence of Pharmaceutical Contaminants and Screening of Treatment Alternatives for Southeastern Louisiana

Abstract: Recent studies conducted in Germany, Switzerland, Denmark, Brazil, Canada, the United States, and elsewhere indicate that low‐level concentrations of pharmaceuticals and personal‐care products (PPCPs) and their metabolites may be widespread contaminants in our aquatic environment. The persistence of pharmaceutical contaminants has been attributed to (1) human consumption of drugs and subsequent discharges from sewage treatment plants, and (2) veterinary use of drugs and nonpoint discharges from agricultural runoff. Contamination of water resources by these compounds, particularly endocrine disrupting chemicals (EDCs), is emerging as an international environmental concern. The long‐term effects of continuous, low‐level exposure to PPCPs is not well understood. Preliminary data for raw water samples collected from the Mississippi River and Lake Pontchartrain, Louisiana, are summarized. Three PPCP compounds (clofibric acid, naproxen, and estrone) were analyzed using solid‐phase extraction, derivatization, and GC/MS. Batch experiments also were conducted to determine equilibrium capacity of activated carbon for clofibric acid. Preliminary results indicate the occurrence of the selected PPCP contaminants in raw water samples at or near method‐detection limits. For batch equilibrium experiments, preliminary results indicate that activated carbon potentially can be used to remove clofibric acid from water. More research is needed to develop rapid and reliable methods for PPCP analysis and to determine the effectiveness of treatment processes for removal of PPCP contaminants in water.

Identification of the bright-greenish-yellow-fluorescence (BGY-F) compound on cotton lint associated with aflatoxin contamination in cottonseed

In order to characterize the structure of the bright-greenish-yellow-fluorescence (BGY-F) compound on cotton lint associated with aflatoxin contamination in cotton seed, various in vitro and in vivo natural BGY-F reaction products were prepared. Under similar high pressure liquid chromatography separation with variable wavelength and programmable fluorescence detection (HPLC-UV/FL), combined with atmospheric pressure ionization and mass spectral determinations it was found that the BGY-F reaction products prepared from three preparations: (a) kojic acid (KA) + peroxidase (soybean peroxide or horseradish type VI and type II) + H2O2, or (b) detached fresh cotton locules + KA + H2O2, or (c) attached field cotton locules that were treated with a spore suspension of aflatoxigenic Aspergillus flavus, all resulted in identical chromatographic characteristics, and all exhibited a molecular weight of 282. Further characterization of the BGY-F reaction product with 1H- and 13C-NMR spectroscopic analysis revealed that it was a dehydrogenator dimer of 2 KA, linked through the C-6 positions.

A combined chemical-enzymatic method to remove selected aromatics from aqueous streams

Aromatics are major pollutants found in aqueous environments and in sediments. Although there are many chemical and biochemical processes to remove and/or treat these contaminants, they have to be considered in light of the economcs and the time scales for treatment. We describe our initial work on a hybrid chemical-enzymatic technique to remove aromatics from aqueous streams. The aromatic is first converted to the corresponding phenol through classical Fentontype chemistry involving catalysis by Fe(II). The phenol is subsequently polymerized through an enzymatic mechanism, using horseradish peroxidase as the oxidative enzyme. The polymer is insoluble in water and can be easily recovered. In addition, such phenolic polymers are useful products with varied applications in coatings and resins technologies. Thus, the pollutants can be eventually converted to useful products.

Colloidal Preparation of γ-Fe 2 O 3 @Au [core@shell] Nanoparticles

γ-Fe 2 O 3 @Au core-shell nanoparticles were prepared through a combined route, in which high temperature organic solution synthesis and colloidal microemulsion techniques were successively applied. High magnification of TEM reveals the core-shell structure. The presence of Au on the surface of as-prepared particles is also confirmed by UV-Vis absorption. The magnetic core-shell nanoparticles offer a promising application in bio- and medical systems.