Environmental protocol tests

Although cyclic environmental chamber test procedures may suffice for failure processes Involving, for example, mechanical stress, kinetic controlled processes dependent upon time and temperature such as oxidation and diffusion do not lend themselves to adequate Identification and analysis based solely on number of cycles. Thus Sandia National Laboratories developed an accelerated aging protocol for environmental testing which (1) identifies material incompatibilities and subsequent failure modes in Phase I and (2) proceeds with kinetic analysis of the Arrhenius type of failure mode processes which allow extrapolation necessary for lifetime prediction of components in Phase II. Thus two phases are necessary in a complete analysis to accurately predict system lifetimes. The accelerated aging protocol requires the Identification of the stresses that are most likely to damage the performance of the component under test. However, data is frequently not available on the performance of a system under a particular stress. When this is the case, it becomes necessary to make predictions of those stresses most likely to cause degradation and then test to see if the stresses selected are dominant. 

Chart showing hierarchical relationship among a technique, methods using that technique, and procedures and protocols for one method. (Abbreviations APHA = American Public Health Association, ASTM = American Society for Testing Materials, EPA = Environmental Protection Agency)... 

In the area of municipal and iadustrial wastewater treatment, the principal environmental issue is the toxicity of residual flocculating agents ia the effluent. Laboratory studies have shown that cationic polymers are toxic to fish because of the iateraction of these polymers with giU. membranes. Nonionic and anionic polymers show no toxicity (82,83). Other studies have shown that ia natural systems the suspended inorganic matter and humic substances substantially reduce the toxicity of added cationic polymer, and the polymers have been used successfully ia fish hatcheries (84—86). Based on these results, the EPA has added a protocol for testing these polymers for toxicity toward fish ia the presence of humic acids (87). The addition of anionic polymers to effluent streams containing cationic polymers to reduce their toxicity has been mentioned ia the patent Hterature (83). 

International agreement is close as of 1996 on what an acceptable environmentally degradable polymer should do ia the environment succiacdy put, it must not harm the environment. There has been much progress ia the early 1990s on this issue standard protocols are available to determine degradation ia the environment of disposal, and definitions are understood and accepted ia a broad sense, if not ia detail. Fate and effects issues for these new polymers are being addressed, and these will be resolved and appropriate tests developed. 

Another issue is the development and refinement of the testing protocols used in mesocosms. Mesocosms could have a more important role in environmental risk assessment if the data coming from them could be better interpreted. The use of biomarker assays to establish toxic effects and, where necessary, relate them to effects produced by chemicals in the field, might be a way forward. The issues raised in this section will be returned to in Chapter 17, after consideration of the individual examples given in Part 2. 

There is a continuing interest in the development of biomarker assays for use in environmental risk assessment. As discussed elsewhere (Section 16.6), there are both scientific and ethical reasons for seeking to introduce in vitro assays into protocols for the regulatory testing of chemicals. Animal welfare organizations would like to see the replacement of toxicity tests by more animal-friendly alternatives for all types of risk assessment—whether for environmental risks or for human health. 

To satisfy government agencies, instruments need to be adequately tested, calibrated, and/or standardized according to documented procedures. Current GLP standards state that equipment used in the generation, measurement, or assessment of data and equipment used for facility environmental control must be of appropriate design and capacity to function according to the protocol and shall be suitably located for operation, inspection, cleaning, and maintenance. 

The American Society for Testing and Materials (ASTM)119 has developed a standard protocol for evaluating environmental chemical-fate models, along with the definition of basic modeling terms, shown in Table 20.17. Predicting fate requires natural phenomena to be described mathematically. 

Chiou, C.T. Schmedding, D.W., "Test Protocols for Environmental Fate and Movement of Toxicants" Zweig, G. and Beroza, M. eds. Association of Official Analytical Chemists, Washington, D.C., 1981, Chapter 3. 

There has been a large number of field trials of transgenic crops that accumulate recombinant proteins, but the results of only a few have been reported so far. Of particular interest for the future are reports of detailed trial protocols that address confinement concerns multi-location, multi-year performance and stability data environmental impact and non-target impact studies and GLP production. The impact of production conditions on extraction efficiency and product quality are also significant issues that should be addressed through field-testing. 

The ISO protocol for the biochemical response EROD (ISO 23893-2/AWI) as a recent example of a bioanalytical (biomarker) [49,50] method standardised under ISO for fish needs harmonisation with the other test systems and between the laboratories (users) before implementation. Use of biomarkers (biochemical responses) in multi-arrays for environmental monitoring according to Hansen et al. [50] is complementary to chemical analysis since they can alert for the presence of ecotoxic compounds. Bringing into the WFD, the effect-related approaches concerning bioassays and biomarkers are only relevant in the context of the QN of environmental relevant substances and the good chemical status. But it is rather difficult to transfer the monitored biochemical responses or biomarkers into an operational effect-related standard. They serve as the basis for environmental protection against hazardous substances. In relation to... 

Proper facilities and care for test animals is not only a matter of regulatory compliance (and a legal requirement), but also essential for a scientifically sound and valid study. Husbandry requires clean cages of sufficient size and continuous availability of clean water and food (unless the protocol requires some restriction on their availability). Environmental conditions (temperature, humidity, and light-dark cycle) must be kept within specified limits. All of these must, in turn, be detailed in the protocols of studies. The limits for these conditions are set forth in relevant NIH and USDA publications. 

Wang YY, Marsden PJ, Flessel CP, et al. 1990. Evaluation and validation of protocols for measurement of the mutagenicity of environmental samples. In Friedman D, ed. Waste testing and quality assurance ... 

Foreign clinical results are acceptable except in areas where there are immunological and ethnic differences between Japanese and foreigners. The ethnic factors are divided into two components intrinsic factors such as racial factors and physiological differences and extrinsic factors, which include cultural and environmental issues. In these cases, the MHLW may require that some bridging comparative clinical trials be performed with dose ranging protocols. This will enable absorption, distribution, metabolism, and excretion studies to be carried out on Japanese individuals and provide better dosage and indication for the Japanese people. The MHLW also requires that application be accompanied by one year of real-time stability data and that sterility test results be included. 

This overview is an attempt to briefly cover the history and recent developments In environmentally degradable commodity and specialty polymers and plastics. Degradation pathways are mentioned, polymer types, including blends, are reported and the limitations of current testing protocols raised. The chapter concludes with generalizations on structural requirements for degradable polymers. 

SDI (1996). Mutatox Direct Test Protocol, Strategic Diagnostics Inc. (formerly Azur Environmental), Newark, DE. 

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