Field studies tools

To increase the usefulness of bioremediation as an effective field remedial tool, significant investments have been made towards the development of means to remove sorbed PAHs, attack sources of NAPL, and subsequently increase the aqueous solubility/bioavailability, and thus the biodegradability, of targeted compounds. To date, one of the most effective ways to accomplish these tasks involves the use of surface active agents (i.e., surfactants). A variety of synthetic surfactants have been shown effective in increasing the bioavailability of PAHs and other hydrophobic contaminants (Kile Chiou, 1989, 1990 Edwards et al., 1991 Liu et al., 1991). Although the solubilization process is not completely understood, these studies showed that a variety of ionic and nonionic surfactants could significantly increase the water solubility of monitored chemicals. 

I think by now it should be clear that compliance with the GLP regulations in the conduct of field studies or residue studies is actually a simple extension of what we have been doing for a decade in animal studies. The requirements for the residue laboratory parallel those for the diet analysis laboratory and should present no serious problems to you. GLPs are a management tool and have nothing to do with science. 

Laboratory toxicity tests have been developed and conducted over the past decades to demonstrate adverse effects that chemicals can have on biological systems. Along with other complementary tools of ecotoxicology available to measure (potential or real) effects on aquatic biota (e.g., microcosm, mesocosm and field study approaches with assessment of a variety of structural and/or functional parameters), they have been, and continue to be, useful to indicate exposure-effect relationships of toxicants under defined, controlled and reproducible conditions (Adams, 2003). 

The further refinement of direct probes and remote sensing tools based on exquisitely sensitive spectroscopic techniques will play an important role in the continued development of stratospheric chemistry and physics. In this regard, it should be noted that most field studies to date have been conducted in relatively narrow geographical regions. Observation of substantial three-dimensional structure (and fine structure) in the stratosphere calls for more extensive geographical coverage in future experiments. 

Roig, B., Valat, C., Allan, I.J., et al., 2007. The use of field studies to establish the performance of a range of tools for monitoring water quality TrAC Trends in Analytical Chemistry, 26(4) 274-82. 

Adding alternative electron acceptors may be a useful tool in the context of ENA. Nitrate, for example, has been used as an especially cost efficient and easy to handle alternative to oxygen. Although MTBE degradation with alternative electron acceptors has been measured in lab-scale experiments, the degradation rates are commonly low and there exists to date no field study using alternative electron acceptors for an ENA approach. 

Chlorinated ethenes are subject to a variety of microbial degradation processes that include reductive dechlorination (Vogel et al., 1987 Maymo-Gatell et al., 1997), aerobic oxidation, anaerobic oxidation (Bradley and Chapelle, 1996), and anaerobic cometabolism (McCarty and Semprini, 1994). Both, laboratory studies (Bradley and Chapelle, 1998), and field studies (Chapelle and Bradley, 2000) show that the efficiency of chlorinated ethene biodegradation depends on ambient redox conditions. Therefore, reliable tools to measure the redox conditions are crucial to imderstand and even predict chlorinated ethene degradation. 

From a hydrogeochemical perspective, there are two major conclusions that can be drawn from this literature review. First, data protocols need to be consistent and complete with respect to redox-sensitive species in order to understand the dynamic behaviour of chlorinated ethenes in the underground and compare it between different sites. Second, the use of the steady-state approach to evaluate field data provided results, which appeared to be more meaningful than those obtained using classical redox chemical parameters. After careful calibration in several field studies, the steady-state approach may allow prediction of in-situ degradation rates and therefore turn out to be a powerful tool for the study of natural attenuation processes. 

Patches are essentially spot or grab samples (typically 25 cm ) of the skin, whereby dermal exposure is assessed by extrapolating the patch loading level to the surface of the entire body. Given that only a small area of exposed skin is covered by the patches used, the uncertainties in calculating true exposure are likely to be high. Furthermore, the exposure pattern may vary with time, with activities, and both within and between individuals, days and shifts. However, several field studies have shown that this technique is a useful tool in the identification and evaluation of dermal exposures to a range of workplace contaminants and in the assessment of the effectiveness of personal protective equipment (Fenske et al. 1990). 

Woods, F. W., and D. O Neal. 1965. Tritiated water as a tool for ecological field studies. Science 147(3654) 148-149. 

Karapanagioti, H.K., Ogata, Y. and Takada, H. (2010) Eroded Plastic Pellets as Monitoring Tools for Polycyclic Aromatic Hydrocarbons (PAH) Laboratory and Field Studies , Global Nest Journal 12 327-34. 

Abstract. Snip is a tool that allows a user to constrict the view onto any window. We report on a controlled study of the snip tool in the context of a multiple-monitor environment. The study was designed based on observed user behavior in a field study of multiple-monitor users snipping habits. Analysis provided results that indicate that users can expect to reference information approximately 15% to 30% faster from snipped windows than from non-snipped windows. Further, users need to pay only a small overhead cost to perform the snip operation. The result extends to other recently presented region-based interface tools that aim to assist multiple-monitor users interact effectively and employ additional monitor space for information-referencing activities. 

Since proposing the idea of a region-based interface to control displayed information in windows [11, 12], we have developed a tool that implements the operation for everyday use in the Microsoft Windows XP system. We have also deployed the tool to a group of multiple-monitor participants in a field study of their window management practices with snip and without it [9]. The key finding from that study is that as compared to periods of time when the snip tool was not available, participants used snip to create space for more visible windows. In other words, multiple-monitor participants actually did use snip to simultaneously show more pieces of information, which can be described as a space-efficiency gain. 

Having reached this point, only field studies using traditional tools can lead to rational explanations and positive results. 

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