Ecotoxicological effects

Svenson, A. and Zhang, L. (1995) Acute aquatic toxicity of protolyzing substances studied as the Microtox effect, Ecotoxicology and Environmental Safety 30 (3), 283-288. 

Mn Mssessment of the Occurrence and Effects of Tdialky I Ortho-Phthalates in the Environment, Technical Report No. 19, European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC), Bmssels, Belgium, 1985. 

The invertebrate phyla are often neglected in ecotoxicological testing protocols. A token invertebrate species such as the copepod Daphnia may be used to evaluate the effects on extremely diverse phyla. This neglects the diversity of biochemical and physiological functions that may render different phyla vulnerable to different classes of compound at different stages of their life cycles. 

ECOTOxicoLOGY The study of toxic effects of chemical and physical agents on living organisms as well as human beings, especially on populations and communities within defined ecosystems. 

The ECOTOXicology database is a source for locating single chemical toxicity data for aquatic life, terrestrial plants and wildlife. ECOTOX integrates three toxicology effects databases AQUIRE (aquatic life), PHYTOTOX (terrestrial plants), and TERRETOX (terrestrial wildlife). These databases were created by the U.S. EPA, Office of Research and Development (ORD), and the National Health and Environmental Effects Research Laborator) (NHEERL), Mid-Continent Ecology Division... 

Muller A, Heininger P, Wessels M, Pelzer J, Griinwald K, Pfitzner S, Berger M (2002) Contaminant levels and ecotoxicological effects in sediments of the river Odra. Acta Hydro-chim Hydrobiol 30 244—255... 

Numerous studies confirmed ubiquity of several antibiotics (i.e., ofloxacin, trimethoprim, roxythromycin, and sulfamethoxazole) in sewage influent, though at low ng level [8, 13, 14]. However, even at very low concentrations they can have significant ecotoxicological effects in the aquatic and terrestrial compartment [15, 16]. Indiscriminate or excessive use of antibiotics has been widely blamed for the appearance of so-called super-bugs that are antibiotic-resistant. It is of crucial importance to control their emissions into the environment through more cautious utilization and monitoring outbreaks of dmg-resistant infections. 

Hadjispyreu S, Kungeles A, Anagncstcpeules A (2001) Toxicity, bioaccumulation, and interactive effects ef organotin, cadmium, and chromium on Artemia franciscana. Ecotoxicology and Environmental Safety, 49 179-186. 

The mechanism of toxic action of some important organic pollutants is described and related, where possible, to ecotoxicological effects. 

Ecotoxicology deals with the study of the harmful effects of chemicals in ecosystems. This includes harmful effects upon individuals, although the ultimate concern is about how these are translated into changes at the levels of population, commnnity, and ecosystem. Thns, in the conclnding sections of the chapter, emphasis will move from the distribntion and environmental concentrations of pollutants to conseqnent effects at the levels of the individnal, population, community, and ecosystem. The relationship between environmental exposure (dose) and harmful effect (response) is fundamentally important here, and full consideration will be given to the concept of biomarkers, which is based on this relationship and which can provide the means of relating environmental levels of chemicals to consequent effects npon individuals, populations, communities, and ecosystems. 

In general, it can be stated that the population density of an animal depends on the balance between the rate of recruitment and the rate of mortality. In the context of ecotoxicology, the influence of pollutants upon either of these factors is of fundamental interest and importance. When a population is at or near its carrying capacity, these two factors are in balance, and the critical question about the effects of pollutants is whether they can adversely affect this balance and bring a population decline. 

Newman, M.C and Unger, M.A. (2003). Fundamentals of Ecotoxicology, 2nd edition—A valuable account of ecological effects of pollutants. 

The next eight chapters will be devoted to the ecotoxicology of groups of compounds that have caused concern on account of their real or perceived environmental effects and have been studied both in the laboratory and in the field. These are predominantly compounds produced by humans. However, a few of them, for example, methyl mercury, methyl arsenic, and polycyclic aromatic hydrocarbons (PAHs), are also naturally occurring. In this latter case, there can be difficulty in distinguishing between human and natural sources of harmful chemicals. 

From an ecotoxicological point of view, it has often been suspected that sublethal effects, such as those described here, can be more important than lethal ones. Both p,p -DDT and p,p -DDD are persistent neurotoxins, and may very well have caused behavioral effects in the field. This issue was not resolved when DDT was widely used, and remains a matter for speculation. More is known, however, about eggshell thinning caused by p,p -DDE and its effects upon reproduction, which will be discussed in Section 5.2.5.I. 

Shore, R.F. and Rattner, B.A. (2001). Ecotoxicology of Wild Mammals—A very detailed, well-structured, and well-referenced text in which organochlorine insecticides and their effects are fully represented. A standard reference work. 

Matthiessen, P. and Gibbs, PE. (1998). Critical Appraisal of the Evidence for TBT-Mediated Endocrine Disruption in Molluscs—A concise review of effects of TBT on molluscs. Scheuhammer, A.M and Sandheimich, M.B (Eds.) (2008). Special issue of the journal Ecotoxicology devoted to effects of methyl mercury on wildlife, which gives recent results of field studies conducted in North America. 

This third part of the book will be devoted mainly to the problem of addressing complex pollution problems and how they can be studied employing new biomarker assays that exploit new technologies of biomedical science. Chapter 13 will give a broad overview of this question. The following three chapters, The Ecotoxicological Effects of Herbicides, Endocrine Disrupters, and Neurotoxicity and Behavioral Effects, will all provide examples of the study of complex pollution problems. 

The following brief account identifies only major groups of herbicides not mentioned elsewhere in the text, and is far from comprehensive. Their mode of action is only dealt with in a superficial way. From an ecotoxicological point of view, there has not been as much concern about their sublethal effects upon plants as there has been in the case of mammals, and there has not been a strong interest in the development of biomarker assays to establish their effects. The major concern has been whether weeds, or nontarget plants, have been removed following herbicide application—a rather easy matter to establish as plants are fairly sedentary. For a more detailed account of herbicide chemistry and biochemistry, see Hassall (1990). 

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