Hw2:5099

From Environmental Technology

Current revision as of 19:18, 5 February 2006

endocrine disrupters?

What are endocrine disrupters? (www.eu.int/comm/environment/endocrine/index_en.htm)

"An endocrine disrupter is an exogenous substance or mixture that alters function(s) of the endocrine system and consequently causes adverse health effects in an intact organism, or its progeny, or (sub)populations" 'Community strategy for endocrine disrupters'

ecotoxicology

Description Ecotoxicology and Environmental Safety is focused on the integrated mechanistic research on short- and long-term pathways and interactions of substances and chemical mixtures in the environmental compartments; on bioavailability; circulation and assimilation in the target organisms, their biological response and damage mechanisms (endocrine disruption, genotoxicity), as well as on a further fate in the food chain including humans. Novel technologies, techniques and methods such as the biomedical photonic technologies, biomarkers, biosensors and bioanalytical systems, QSARs and QSPRs, advanced high-performance computational methods, models and storage systems, and their applications in the obtaining and processing of interdisciplinary ecotoxicological information, are also addressed in the journal. We welcome the applied outcome of the complex ecotoxicological research such as developing the science-based Environmental Quality Criteria (EQC), standard toxicity tests, techniques and methods for ecotoxicological evaluation of the environment, as well as developing ecotoxicologically proven methods and technologies for prevention, interception and remediation of human-induced damage to ecosystems. The above scope of the Journal is aimed on providing science-based tools for sustainable managing the environment: risk assessment, risk characterization, risk prediction and risk management. Progress in the Ecotoxicology and Environmental Safety is reflected in the review section presenting, summarizing and analyzing state-of-the-art within the scope and aims of the Journal. Short solicited book reviews, advertisements and announcements of events (symposia, conferences, workshops) of general interest to researchers involved in ecotoxicology are also welcome.

ecological risk assessment

This site contains information and resources on a variety of topics related to the growing field of ecological risk analysis. This is an updated and expanded version of the original ORNL site by this name. Whereas the previous version focused on ecological risk assessments for hazardous waste sites (i.e., chemicals), this site now contains information on the expanded role of ecological risk analysis in environmental decision making. All of the tools that made this site popular with risk assessors in the 1990s are still available. However, ORNL has been applying the principles and practices of ecological risk analysis to non-chemical stressors and to environmental management issues other than those typically associated with CERCLA remedial investigations, e.g., military training and testing activities. Information, tools, and other resources are provided for each of these areas below.

bioaccumulation

Bioaccumulation Bioaccumulation is a general term for the accumulation of substances, such as pesticides (DDT is an example), methylmercury, or other organic chemicals in an organism or part of an organism. The accumulation process involves the biological sequestering of substances that enter the organism through respiration, food intake, epidermal (skin) contact with the substance, and/or other means. The sequestering results in the organism having a higher concentration of the substance than the concentration in the organism’s surrounding environment. The level at which a given substance is bioaccumulated depends on the rate of uptake, the mode of uptake (through the gills of a fish, ingested along with food, contact with epidermis (skin), …), how quickly the substance is eliminated from the organism, transformation of the substance by metabolic processes, the lipid (fat) content of the organism, the hydrophobicity of the substance, environmental factors, and other biological and physical factors. As a general rule the more hydrophobic a substance is the more likely it is to bioaccumulate in organisms, such as fish. Another way of saying this is that bioaccumulation of a substance is correlated to the octanol-water partition coefficient (KOW) of the substance. Increasing hydrophobicity (lipophilicity) leads to an increasing propensity to bioaccumulate. Some substances do not conform to this relationship, such as methlymercury. Methlymercury accumulates in fish to a much greater degree than methlymercury’s KOW would indicate.

emerging disease

Introduction Despite remarkable advances in medical research and treatments during the 20th century, infectious diseases remain among the leading causes of death worldwide for three reasons: (1) emergence of new infectious diseases; (2) re-emergence of old infectious diseases; and (3) persistence of intractable infectious diseases. Emerging diseases include outbreaks of previously unknown diseases or known diseases whose incidence in humans has significantly increased in the past two decades. Re-emerging diseases are known diseases that have reappeared after a significant decline in incidence. Within the past two decades, innovative research and improved diagnostic and detection methods have revealed a number of previously unknown human pathogens. For example, within the last decade chronic gastric ulcers, that were formerly thought to be caused by stress or diet, were found to be the result of infection by the bacterium Helicobacter pylori.

pollution

    Comprising over 70% of the Earth’s surface, water is undoubtedly the most precious natural resource that exists on our planet.  Without the seemingly invaluable compound comprised of hydrogen and oxygen, life on Earth would be non-existent: it is essential for everything on our planet to grow and prosper.  Although we as humans recognize this fact, we disregard it by polluting our rivers, lakes, and oceans. Subsequently, we are slowly but surely harming our planet to the point where organisms 

are dying at a very alarming rate. In addition to innocent organisms dying off, our drinking water has become greatly affected as is our ability to use water for recreational purposes. In order to combat water pollution, we must understand the problems and become part of the solution.

biological amplification

carcinogen

environmental stressor

Stressors CCMA's research addresses five major environmental stressors. These are: Pollution, Land and Resource Use, Invasive Species, Climate Change, and Extreme Events.

red tides

RED TIDE: Not every plant poisoning is caused by a large, terrestrial plant. Several microscopic marine algae are notoriously poisonous to hapless humans who consume them in shellfish. These Algae are tiny, single-celled plants that, like plants on land, capture and use the sun's energy to grow. The growth of algae is an essential life process, as it is the first step in transferring solar energy into aquatic food webs. The huge variety of marine algae are typically subject to annual cycles of growth & decay. These organisms thrive and multiply principally during the spring and summer, in response to increased light intensity and favourable levels of salinity & nutrients in ocean water. During the growth period, or bloom, each single algae cell may replicate itself one million times in two to three weeks.

During the reproductive riot of the bloom, warm, shallow seawater tends to become discoloured by the sheer concentration of algae seeking the sunlight. This discolouration is a result of the various pigments the plants use to trap sunlight; depending on the species of algae present, the water may reflect pink, violet, orange, yellow, blue, green, brown, or red. Since red is the most common pigment, the phenomenon has come to be called Red Tide.

Most species contributing to algal blooms are harmless, BUT (another big but!) some species are poisonous to animals which feed upon them directly or indirectly. Some of the toxins these species produce are seriously toxic. Often, the algae themselves are unaffected, as are the filter feeders, especially shellfish, for whom micro-algae are the principal diet. However, to carnivores further up the food chain, including humans, these toxins are potentially FATAL.