Environmental analysis degradation products

Environment. Detection of environmental degradation products of nerve agents directly from the surface of plant leaves using static secondary ion mass spectrometry (sims) has been demonstrated (97). Pinacolylmethylphosphonic acid (PMPA), isopropylmethylphosphonic acid (IMPA), and ethylmethylphosphonic acid (EMPA) were spiked from aqueous samples onto philodendron leaves prior to analysis by static sims. The minimum detection limits on philodendron leaves were estimated to be between 40 and 0.4 ng/mm for PMPA and IMPA and between 40 and 4 ng/mm for EMPA. Sims analyses of IMPA adsorbed on 10 different crop leaves were also performed in order to investigate general apphcabiflty of static sims for... 

For organic toxic chemicals and their degradation products the number of possibilities is very high. The environmental samples composition usually is very complicated. Unambiguous identification needs serial-pai allel strategy of analysis with many-stage crosschecking of data. 

Reliable analysis of endosulfan residue concentrations in environmental samples usually involves detection of the a- and p-isomers plus endosulfan sulfate (a degradation product of endosulfan). 

An enzyme immunoassay technique has been employed for measuring endosulfan and its degradation products (i.e., endosulfan diol, endosulfan sulfate, endosulfan ether, and endosulfan lactone) in water at 3 ppb (Chau and Terry 1972 Musial et al. 1976). However, this technique is not currently in use in environmental residue analysis. Further research into this technique could produce a rapid, rehable, and sensitive method for identifying contaminated areas posing a risk to human health. No additional methods for detecting endosulfan in environmental media appear to be necessary at this time. However, methods for the determination of endosulfan degradation products are needed. 

Methods for determining acrylonitrile in environmental samples are quite good. It may be assumed that the normal incentives for both research and the development of commercial methods of analysis will result in new analytical methods for acrylonitrile that have improved sensitivity and selectivity. Degradation products of acrylonitrile in environmental media are difficult to determine. This difficulty is not as much an analytical problem as it is a problem of knowing the fundamental environmental chemistry of these compounds in water, soil, air and biological systems. 

The PRISTINE project, and thus the content of the present book, provides policy makers and industry with detailed information on analysis and concentrations of surfactants and their degradation products in the environment. Furthermore, the book provides relevant information to all groups working in the field of surfactants in environmental laboratories, environmental agencies, the surfactant industry, water industry and sewage treatment facilities. 

Although a substantial body of data is available on the levels of linear alkylbenzene sulfonates (LASs) in rivers and estuaries, fewer studies have been conducted on their environmental behaviour, with reference to the mechanisms involved in their transport and to the reactivity they undergo. Studies of LAS in subterranean water and in the marine medium are scarce and have mainly been conducted in the last decade [2-6], coinciding with the development of new techniques of concentration/separation and analysis of LAS at ppb levels or less. Data on concentrations of sulfophenyl carboxylates (SPCs) are very scarce and the behaviour of these intermediates has hardly received any study. This chapter provides an overview of the current knowledge on behaviour of LAS and their degradation products in coastal environments. 

In the environmental field, the applications include analysis of explosives and their degradation products in soil and water. These analyses are important because of the toxicity of most explosives and the fact that many areas in the vicinity of explosives and munitions manufacturing plants are contaminated. 

Methods for Determining Parent Compound and Degradation Products in Environmental Media. While analytical methods appear to be available for the analysis of 1,2-diphenylhydrazine, no methods were found for the preservation of 1,2-diphenylhydrazine in ambient air, water, or soil samples. Such methods would allow the development and analysis of a monitoring program designed to better assess the concentrations of 1,2-diphenylhydrazine in and around hazardous waste sites. 

Methods for Determining Parent Compounds and Degradation Products in Environmental Media. Methods have been described for the determination of 3,3 -dichlorobenzidine in air, with reported limits of detection of 0.5 g/m (NIOSH 1994) and 3 g/m (Morales et al.l981). Methods for the analysis of 3,3 -dichlorobenzidine in water and waste water have also been described, with reported detection limits of 16.5 g/L (ppb) (EPA 1982b Greenberg et al. 1992), 50 g/L (ppb)... 

No adequate methods appear to be available for the analysis of isophorone degradation products in environmental media. In cases where a degradation product of a chemical is toxic, it is important that its concentration in the environment be known. In certain instances, monitoring the level of a degradation product may be used as an indirect measurement of the parent compound in the environment. 

It would be helpful to develop data determining the accuracy of PBDE determinations (e.g., percent recovery) in environmental samples. Methods for determining degradation products and metabolites of PBDE are needed. There is no information in the literature of detectable biodegradation of PBDEs in the environment under aerobic or anaerobic conditions. The analysis of PBDE pyrolysis degradation products, such as polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), is often disturbed by the presence of PBDEs. Ebert et al. (1999) demonstrated that by using a Florisil column ina sample clean-up process, almost complete separation of PBDEs and PBDD/Fs is achieved before analysis by GC-MS. 

One advantage of HPLC is that the analysis of unstable pesticides may be performed directly in aqueous medium without the extraction step or following extraction and concentration. Although the direct approach is quite useful for formulations or for kinetic studies to monitor the parent compounds in the presence of degradation products, its usefulness is limited in the case of environmental samples, where the concentration is usually in the parts-per-billion range (31). 

Methods for Determining Parent Compound and Degradation Products in Environmental Media. Air is the only environmental medium susceptibleto significant contamination by BCME and methods for the determination of this compound in air are straightforward. The greatest need for improvement in the analysis of BCME is the development of methodologies... 

In the case of degradation products and metabolites, the situation is different. Generally, these compounds were not analysed because in most cases they are not regulated and no effective analytical methods exist for their determination. This means that a correct diagnosis of the environmental situation cannot be made and, as a consequence, no appropriate action can be taken. Therefore, in order to improve the risk assessment of a hazardous waste site for example, as many compounds as possible should be analysed at the beginning of the investigations (non-target analysis). 

From the selectivity point of view, LC-NMR coupling is especially suited to the analysis of compound classes such as nitroaromatics, phenols, aromatic amines, aromatic carboxylic acids, polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and azo- and anthraquinone dyes. Another advantage of LC-NMR coupling for the investigation of aromatic compounds in environmental samples is that the position of substituents on the aromatic ring, e.g. in unknown metabolites or degradation products, can best be determined by NMR spectroscopy. 

Abian, J. and G.D. Barceld (1993). Analysis of chloro-triazines and their degradation products in environmental samples by selecting various operating modes in thermospray HPLC/MS/MS. J. Agri. Food Chem., 41 1264-1273. 

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