Plants, toxicological hazard

Data on human poisoning by plants are collected in a manner that is fundamentally different from that collected on animals. Whereas identification of a potential toxicological hazard to humans or animals may begin with reports of intoxication, toxicity of plants suspected of injuring animals may be confirmed in controlled feeding studies. Experiments designed solely to establish toxicity to humans are... 

Benzoxazolone (83) and its 6-methoxy derivative (84) are present in plants and are said to act as fungicides, bactericides and insecticides. Plants also possess the enzyme system which is responsible for the degradation of benzoxazolones. It was to be expected therefore that also synthetic insecticides containing a benzoxazolone moiety will prove to be biodegradable, thus decreasing toxicological hazards. 

Uncontrolled chemical reactions are not the only sources of hazard in a process plant. This chapter briefly considers the risks of fire and explosion, and toxicological hazards. All types of hazard should be fully assessed by competent personnel using specialist advice where necessary. (See also case histories Al 70-78, pages 186-188.)... 

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 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. 

Mancuso TF. 1951. Occupational cancer and other health hazards in a chromate plant A medical appraisal II. Clinical and toxicologic aspects. Ind Med Surg 20 393-407. 

Reports about the fate and behavior of any pesticide applied In different kinds of formulations to plants are rather limited. This Is true even more so for the other constituents of formulations Including surfactants. McWhorter (j ) has estimated that considerable quantities of surfactants are applied to plants with pesticides. The general assumption Is that these constituents present lesser environmental hazards than the pesticides. Parr ( ) has discussed some aspects of surfactant toxicology. 

Eason, C. (2002). Sodium monofluoroacetate (1080) risk assessment and risk communication. Toxicology 181-2 523-30. Eisler, R., Wiemeyer, S.N. (2004). Cyanide hazards to plants and animals from gold mining and related water issues. Rev. Environ. Contam. Toxicol. 183 21-54. 

Since clinical trials and toxicology studies require increasing amounts of product, an intermediate scale-up is often necessary. Scale-up may be performed in a pilot plant or in intermediate-sized laboratory equipment on-site or at a contract facility. As the scale increases, evaluation of the hazardousness of the operation sequence becomes necessary. Hazardous operation analysis may be done during this intermediate scale-up or during the detailed design. It is useful to take the results of the gap analysis and collect the appropriate data during intermediate scale-up. 

Toxicological properties of intermediates and impurities often dictate safe handling considerations on scale, as routine laboratory safety techniques may not transfer easily to the pilot plant and larger scales. Information on the safety of purchased chemicals may be found in the relevant MSDS. Intermediates prepared during processing may be hazardous to operators, and special handling may be... 

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