Organic parameters

Secondary to the societal concerns around chemical-related endocrine disruption, the OECD407 subacute 28-day toxicity study protocol has been updated in 2007 with parameters relating to endocrine homeostasis. Specifically, circulating thyroid hormones and detailed assessment of reproductive organ parameters were added to the protocol. Reproductive hormones were suggested as additional parameters but they were deemed not informative in view of their large variability in untreated animals. 

Organic parameters are primarily for solvents. All-atom and united-atom versions exist. 

Understanding second order nonlinearities in terms of simple well known physical-organic parameters requires starting from the standard perturbation theory expressions and then deriving the more limited expressions which can be related to simple physical observables. It is best to approach perturbation theory from a phenomenological direction, since this can ultimately provide a more intuitive understanding of the physics. We start with the second harmonic generation process. 

Other Design Parameters Facility design parameters that support the process within the clean room should be established by the user organization. Parameters such as temperature, humidity, lighting requirements, sound level, and/or vibration may be process driven or comfort driven and therefore are selected to accommodate specific process or comfort requirements as determined by the end user. 

Annexes 5.1 and 12.1 give examples of reporting forms elaborated in BCR (Bureau Communautaire de Reference) for the certification of inorganic and organic parameters in environmental matrices. They may be used as a basis to prepare reporting forms for all type of interlaboratory studies. The elaborate questions listed in the forms are intended to remind the participant of important parameters, which affect the quality of the final result. They can also be used in the technical discussion with the other participants when differences in results are noticed. Finally, they form the basic information for the preparation of certification reports in case certification is considered (see chapter 5). 

Target organ/ parameter Disorders Therapeutic effect... 

The estimation of the main aggregated organic parameters for water and wastewater is one of the first applications of UV spectrophotometry. As a lot of organic compounds absorb in the UV region (see Chapter 3), the exploitation of UV spectrum for a quick... 

Figure 11. General procedure for aggregate organic parameter estimation (e.g. chemical oxygen demand) with a model of p reference spectra of mixture and q of specific compounds (r is the restitution error, which must be minimal see Chapter 2).

Several validation experiments have been carried out for water and wastewater quality monitoring. Tables 4 and 5 present the general conditions and the results of UV estimation of aggregated organic parameters. 

Table 4. Validation experiments for UV estimation of aggregate organic parameters (generalities)...

At the end of this chapter, it can be interesting to qualitatively compare the different parameters with the UV response of families of organic compounds. Figure 27 presents different domains (families of organic and mineral compounds) that are related to the aggregate organic parameters and to the UV samples response. 

Figure 27. Significance of aggregate organic parameters and UV response. Table 7. COD, BOD, TOC and UV responses of organic compounds...

Figure 28. Theoretical evolution of aggregate organic parameter and UV response with degradation time of urban wastewater (UV expressed, for example, as the area under spectrum for wavelength >230 nm).

One of the most important applications of UV spectrophotometry, particularly for industrial wastewater quality control, is the rapid estimation of the concentration of some substances or some parameter values, among which are aggregate organic parameters and N or P compounds (Table 3). 

It is generally agreed that an air-dried (30 5°C) sample is satisfactory for toxic metals and other non-labile parameters such as elemental sulfur. Foss or degradation of many organic parameters (e.g. phenols, VOCs, TPH, etc.) and other labile parameters, such as easily libera table cyanide, can occur on... 

Different laboratories have different routine protocols to overcome this problem but whatever the processes employed, initial sample handling must minimise the loss or chemical alteration of important analytical parameters (e.g. reduction of sulfates, biological breakdown of nitrates, volatilisation of As, Sb, Hg and volatile organic parameters). 

Normal blood, urine, milk and organ parameters... 

Whole body level parameters are determined by multiple organ parameters, which in turn are a reflection of multiple macromolecular parameters. Thus, in the case of a pair of enantiomers, the observed stereoselectivity for a particular parameter is dependent on the level of organization that the parameter represents and may be either amplified or attenuated [94]. For example, in the case of warfarin, the enantiomeric ratio (R/S 1.93) in half-life is determined primarily by differences in volume of distribution (R/S 1.83) rather than the modest difference in elearanee (R/S 1.05). In contrast, examination of the alternative metabolic routes generates marked differences in stereoselectivity, e.g., aromatic oxidation at the 6-, 7-, and 8-positions of the coumarin ring yields enantiomeric ratios of R/S 1.19, S/R 6.33, and R/S 5.2, respectively. These, together with the... 

CEN and ISO have already published a ntunber of standard methods suitable for the determination of most of contaminants for the control of the quality of water. For the determination of anions and elements several alternative single and multiple component methods have been approved. For the determination of organic parameters generally multiple-component procedrtres are available. 

Also listed are recommendations for the application of existing CEN and ISO methods, generally automated multiple-component procedures, suitable for routine analyses with high sample throughput, except for standard methods for the determination of organic parameters which could be time eonsuming. Nevertheless, any laboratory ean choose any alternative method of its ehoice as long as it is eapable of... 

The equations derived above form a complete representation of a simple generic phototrophic organism. Parameter values, which are typical for such processes, are chosen as given in Tables 1 and 2. 

---