Plant toxicology

A. A. Seawright, M. P. Hegarty, L. F. James and R. F. Keeler, Plant Toxicology, Queensland Dept of Primary Industries, Yeerongpilly, Australia, 1985. 

Much of the early history of toxicology has been lost and in much that has survived toxicology is of almost incidental importance in manuscripts dealing primarily with medicine. Some, however, deal more specifically with toxic action or with the use of poisons for judicial execution, suicide or political assassination. Regardless of the paucity of the early record, and given the need for people to avoid toxic animals and plants, toxicology must rank as one of the oldest practical sciences. 

Since all this information is vital to developing an operational attack on the problem, Delbert C. McCune provides a summary and synthesis of plant toxicology to establish several possible schemes to organize our thinking and to provide a basis for future action. 

Hoeger, S.J., Hitzfeld, B.C., D.R. Dietrich, Occurrence and elimination of cyanobacterial toxins in drinking water treatment plants. Toxicology and Applied Pharmacology, 2005 203(3) 231-242. 

C. Fedtke, S. O. Duke in Plant Toxicology, B. Hock, E. E. Elstner... 

Sakihama, Y, Cohen, M.F., Grace, S.C., Yamasaki, H. (2002). Plant phenolic antioxidant and prooxidant activities phenofics-induced oxidative damage mediated by metals in plants. Toxicology, 177,67-80. 

Bell, E. A. 1985. The Biological Significance of Secondary Metabolites in Plants. In Plant Toxicology, Seawright, A. A., Hegarty, M. P. J. L. F., and Keeler, R. F., eds. Yeerongpilly. Queensland. Queensland Dept, of Primary Industries, Animal Research Institute, pp.50-56. 

Acrolein, acrylamide, hydroxyalkyl acrylates, and other functional derivatives can be more hazardous from a health standpoint than acryhc acid and its simple alkyl esters. Furthermore, some derivatives, such as the alkyl 2-chloroacrylates, are powerful vesicants and can cause serious eye injuries. Thus, although the hazards of acryhc acid and the normal alkyl acrylates are moderate and they can be handled safely with ordinary care to industrial hygiene, this should not be assumed to be the case for compounds with chemically different functional groups (see Industrial hygiene Plant safety Toxicology). 

The toxicological problems associated with asbestos have been widely pubHshed and asbestos has been banned from most uses by the EPA. However, modem diaphragm cell chlorine plants have not had difficulty meeting the required exposure limits for asbestos fibers, and, as of 1990, the chlorine industry had an exemption allowing the continued use of asbestos as a diaphragm material. 

The OSHA limits, regulations, and recommendations apply to in-plant air quaUty. Improperly filtered exhaust air may cause a plant to be in violation of the EPA standard, therefore these data should not be confused with the EPA limit for airborne lead, 1.5 fig lead/m, measured over a calendar quarter, which pertains to the exterior plant environment and emissions. The installation and proper maintenance of exhaust filtration systems enables most plants to comply with the EPA limits for airborne lead (see Lead compounds, industrial toxicology). 

See AnTI-ASPHMATIC AGENTS InDUSTRIAD HYGIENE AND PLANT SAFETY TOXICOLOGY. 

The first major objective for the inherent safety review is the development of a good understanding of the hazards involved in the process. Early understanding of these hazards provides time for the development team to implement recommendations of the inherent safety effort. Hazards associated with flammability, pressure, and temperature are relatively easy to identify. Reactive chemistry hazards are not. They are frequently difficult to identify and understand in the lab and pilot plant. Special calorimetry equipment and expertise are often necessary to fully characterize the hazards of runaway reactions and decompositions. Similarly, industrial hygiene and toxicology expertise is desirable to help define and understand health hazards associated with the chemicals employed. 

Typical events that are considered are fire, explosion, ship collision, and the failure of pressurized storage vessels for which historical data established the failure frequencies. Assessment of consequences was based partly on conservative treatment of past experience. For example ilic assessment of the number of casualties from the release of a toxic material was based on past histoiy conditioned by knowledge of the toxicology and the prevailing weather conditions. An altemati. e used fault trees to estimate probabilities and identify the consequences. Credit is taken in this process for preventative measures in design, operation, and maintenance procedures. Historical data provide reliability expected from plant components and humans. 

Since the OELs provide the basis for ventilation requirements, an astute designer tries to find out how secure the OELs of the chemicals which will be used in the plant he or she is planning. Some of the chemicals used may totally lack OELs. Therefore, it is advisable to become familiar with the relevant literature, preferably together with a specialist. It is clear that the ventilation engineer needs to be aware of the possible significance of toxicology for industrial ventilation construction. 

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... 

Gift-jasmin, m. Carolina jasmine (Gelsemium sempervirens). -kies, m. arsenopyrite. -kobalt, m. native arsenic, -kraut, n. poisonous plant, -kunde, /. toxicology, -lattich, m. strong-scented lettuce (Lactuea virosa). -lehre, /. toxicology. 

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