Contamination sources identification

Liu C, Ball WP (1999) Application of inverse methods to contaminant source identification from aquitard diffusion profiles at Dover AFB. Delaware Water Resour Res 35 1975-1985... 

Snodgrass MF, Kitanidis PK (1997) A geostatistical approach to contaminant source identification. Water Resour Res 33 537-546... 

A definition of the aseptic techniques and work practices of operative personnel, and a report of findings based upon videotaped observation of the actual work stream during prequalification runs for identification and elimination of personnel-generated contamination sources, identification of susceptible areas including critical sites and steps, and indicator sites ... 

Terrado M, Barcelo D, Tauler R (2006) Identification and distribution of contamination sources in the Ebro river basin by chemometrics modelling coupled to geographical information systems. Talanta 70 691-704... 

Fig. 5 Main contamination sources identified by PCA for sediments, fish, and suface water in the Ebro River basin, and explained variances for each principal component. Variable identification. Organic compounds in sediments 1, summatory of hexachlorocyclohexanes (HCHs) 2, summa-tory of DDTs (DDTs) 3, hexachlorobenzene (HCB) 4, hexachlorobutadiene (HCBu) 5, summatory of trichlorobenzenes (TCBs) 6, naphthalene 7, fluoranthene 8, benzo(a)pyrene 9, benzo(b) fluoranthene 10, benzo(g,h,i)perylene 11, benzo(k)fluoranthene 12, indene(l,2,3-cd)pyrene. Organic compounds in fish 1, hexachlorobenzene (HCB) 2, summatory of hexachlorocyclohexanes (HCHs) 3, o,p-DDD 4, o,p-DDE 5, o,p-DDT 6, p,p-DDD 7, />,/>DDE 8, />,/>DDT 9, summatory of DDTs (DDTs) 10, summatory of trichlorobenzenes (TCBs) 11, hexachlorobutadiene (HCBu) 12, fish length. Physico-chemical parameters in water 1, alkalinity 2, chlorides 3, cyanides 4, total coliforms 5, conductivity at 20°C 6, biological oxygen demand 7, chemical oxygen demand 8, fluorides 9, suspended matter 10, total ammonium 11, nitrates 12, dissolved oxygen 13, phosphates 14, sulfates 15, water temperature 16, air temperature...

Although Rs values of high Ks compounds derived from Eq. 3.68 may have been partly influenced by particle sampling, it is unlikely that the equation can accurately predict the summed vapor plus particulate phase concentrations, because transport rates through the boundary layer and through the membrane are different for the vapor-phase fraction and the particle-bound fraction, due to differences in effective diffusion coefficients between molecules and small particles. In addition, it will be difficult to define universally applicable calibration curves for the sampling rate of total (particle -I- vapor) atmospheric contaminants. At this stage of development, results obtained with SPMDs for particle-associated compounds provides valuable information on source identification and temporal... 

Eshete, D.W. and Chyi, L.L. (2003) Source identification and natural attenuation of arsenic contaminated groundwater in northeastern Ohio. Abstracts with Programs. The Geological Society of America, 35(6), 565. 

As PAHs are widespread contaminants produced as a result of natural cycles (e.g., forest fires, plant decomposition and petrogenesis), as well as industrial activities, identification of anthropogenic PAHs contaminant sources is a challenge, particularly as atmospheric emissions are subject to long-range atmospheric transportation processes (Lockhart et al., 1992 ... 

Aral MM, Guan J,Maslia ML (2001) Identification of contaminant source location and release history in aquifers. J Hydrol Engin 6 225-234... 

Sidauruk P, Cheng A, Ouazar D (1998) Ground water contaminant source and transport parameter identification by correlation coefficient optimization. Ground Water 36 208-214... 

Identification of Specific Labels in Potential Contamination Sources... 

Glass GE, Sorensen JA, Schmidt KW, et al. 1990. New source identification of mercury contamination in the Great Lakes. Environ Sci Technol 24(7) 1059-1069. 

The U.S. EPA is charged with addressing air pollution under the Clean Air Act. The poor air quality found in California has led the state of California to establish the California Air Resources Board (ARB), which also addresses this subject. EPA has established a list of hazardous air pollutants anci ARB has established a Toxic Air Contaminant (TAC) Identification List. 4 Numerous other literature references identify still other known air pollutants. Table 7.1, toxic chemicals in the air, which was compiled from these sources, shows the range of pervasive toxic chemicals that are found in the air we breathe. 

Three assessment phases are recognised widely. The first is hazard identification this is described as a Phase la investigation. In this, a conceptual model is developed for the site that identifies potential receptors, contaminant sources and pathways, by which contamination can reach receptors. The second phase (Phase lb) tests the conceptual model, by collecting and analysing quantitative information to support model validation. The final phase is risk assessment (Phase 2) in which the conceptual model is used to estimate and evaluate the actual or potential risks to receptors. 

The concentration values of some pesticides and heavy metals are not so high, but their presence indicates a high degree of pollution and permits the identification of the principal contamination sources. We have detected a high concentration of p HCH, Pb and Hg over maximal admitted limits which represent an alarm signal for human and environmental health. 

The initial problem before commencing identification is to obtain a bacterial isolate in pure culture, and before beginning any biochemical tests the purity of the cultures should be confirmed by plating out onto solid non-selective media. Selective media should not be used as many selective media only suppress the growth of unwanted organisms they do not kill them. In the case of highly contaminated sources, such as faeces, the isolation and purification procedures may take several days. Methods for doing this are discussed in Chapter 3. 

Source indicators-As source indicators, molecular markers are applied either qualitatively (source identification) or quantitatively (source apportionment). The requirements for quantitative source apportionment are considerably more stringent and the number of examples in the literature is fewer than for source identification (e.g. Schauer et al., 1996 Eganhouse and Sherblom, 2001 Takada et al., 1997). Specific biogenic markers have been used for chemotaxonomic purposes (Kates, 1997) and to characterize the composition of benthic and pelagic communities present in aquatic ecosystems (Findlay and Watling, 1997). Many fossil biomarkers have served as indicators of organic matter provenance (Peters and Moldowan, 1993) or for paleoclimate reconstruction (Brassel et al., 1986). Biomarkers are also used frequently to identify sources of fossil fuel contamination in the contemporary environment (Kaplan et al., 1997 Volkman et al., 1997). Finally, there are numerous studies in which molecular markers associated with municipal wastes, urban mnoff, or combustion of fossil fuels have been used to infer the effect of various point and non-point sources of contamination (see references in Takada and Eganhouse, 1998). 

Silva et al. [122] discuss the source identification of nitrate contamination in the urban environment utilizing nitrogen and oxygen stable isotopes in conjunction with hydrologic data and water chemistry. The authors reported that the isotopes of nitrate permitted differentiation between sewage nitrates and other sources of nitrate (e.g., fertilizers). 

Pond, K.L., Huang, Y., Wang, Y, Kulpa, C.F. (2002) Hydrogen isotopic composition of individual n-alkanes as an intrinsic tracer for bioremediation and source identification of petroleum contamination. Environ. Sci. Technol, 36,724-728. 

The priorities in this case are the prompt isolation and confinement of source of exposure (find the source) and significant contamination, the identification and control of potentially exposed individuals, and the decontamination of people and affected areas. 

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