Dinoseb toxicity

There are at least 22 chemical families of organic herbicides. Even a cursory treatment of the chemistry of these materials would be extensive. Herbicides of limited toxicity (Treflan, Atrazine) as well as extremely toxic ones (Paraquat. Dinoseb) are in use in many parts of the world. They range from water soluble to insoluble. The detailed chemistry of each should be determined prior to handling. 

Considerations for the acceptability of the are similar to those for the uncertainty factor used to calculate the RfD, RfC or other reference values from the NOAEL or BMD. The has been calculated from reproductive toxicity data for several chemicals. Examples include dinoseb (US EPA, 1986), lithium (Moore, 1995) and boric acid and borax (Moore, 1997). In the case of dinoseb, the MOEs were very low, in some cases less than one, indicating toxicity in the animal studies at levels to which people are exposed. This information on dinoseb led to an emergency suspension of use of this pesticide in the USA in 1986 and ultimately led to its removal from the market (Kimmel Kimmel, 1994,1996). 

Dinoseb is a nitrophenolic compound, once widely used as an herbicide and plant desiccant, that is noted for its toxic effects. The chemical name of this compound is 4,6-dinitro-2-,v< o butylphenol, and its structure is... 

Metabolomics has made remarkable inroads into the environmental research community. Here, a major emphasis is to understand the impact that environmental stress, such as pollution and climate change, has on wildlife. Indeed, many government organizations monitor the prevalence of pollutants in certain species of wildlife as indicators of the exposure risk within the environment. Studies of Japanese medaka have been conducted to investigate the effects of trichloroethylene, a common environmental pollutant, and the pesticide dinoseb, on the development of fish embryos (44, 45). Similarly, cadmium toxicity has been examined in the bank vole and rat and has revealed changes in lipid metabolism that preceded classical nephrotoxicity (46, 47). Another study investigated the effects of environmental toxins on earthworms (48). In particular, the analysis of earthworm tissue extracts by NMR spectroscopy identified maltose as a potential biomarker for ecotoxicity within a metal-contaminated site. 

Viant MR, Pincetich CA, Hinton DE, Tjeerdema RS. Toxic actions of dinoseb in medaka (Oryzias latipes) embryos as determined by in vivo 31P NMR, HPLC-UV and IH NMR metabolomics. Aquat. Toxicol. 2006 76 329-342. 

Dinoseb is highly toxic to birds, with oral LD50 values less than lOmgkg and 5-8 day dietary LC50 values of around 500 ppm. Dinoseb is highly toxic to fish, with 96 h LC50 values of 44-118 pgl. Dinoseb use can lead to fish kills from runoff following rain. Dinoseb is not bioaccumulated. Dinoseb is also toxic to bees. 

Pesticides with this mode of action include such old products as the dinitrophenols (dinitroorthocreosol [DNOC], dinoterb, and dinoseb) and other phenols such as pentachlorophenol and ioxynil. DNOC is a biocide useful against mites, insects, weeds, and fungi. The mammalian toxicity is rather high, with a rat oral LD50 (lethal dose in 50% of the population) of 25 to 40 mg/kg of the sodium salt. The typical symptom is fever, which is... 

DNOC is strongly toxic to mammals. The acute oral ld is for rats 25-40 mg/kg. Dinoseb, 2-see-butyl-4,6-dinitrophenol (3) was first described as a herbicide by Crafts (1945). 

Dinoseb is strongly toxic to mammals. The acute oral for rats is 58 mg/kg the acute dermal lDjq for rabbits is 80-200 mg/kg. In 180-day feeding trials rats receiving 100 mg/kg diet suffered no ill effect. 

The acetylation of dinoseb yields dinoseb acetate (4). It is somewhat less toxic than the parent compound. Dinoseb acetate was introduced by the Hoechst AG in 1958 and its herbicidal properties were first reported by Haertel (1960). 

Environmental pollution by toxic chemicals has become one of the worlds most serious problems. Among the most widespread pesticides is photosynthesis inhibiting herbicides, such as atrazine, metribuzin, diuron, bromacil, ioxynil and dinoseb. They all beloi to different families but have a common mode of action binding specifically to the chloroplast D1 protein with subsequent intetmption of the electron and proton flow through Photosystem II. The goal of this chapter is to evaluate the possibility of application of the natural receptor properties of D1 protein in various biosensor systems for herbicide detection. 

Dinoseb is a highly toxic compound. The oral LD50 values in small laboratory animals were between 10 and 25 mg/kg. Acute toxicity tests on daphnids and fathead minnows showed high toxicity. The LC50 values in both these species are 0.24 and... 

The pesticides chIorpyrifos, ,4-D acid, 2,4-DP acid, dicamba, dinoseb, and propaniI were positive in the bacterial relative toxicity assays (propaniI in B. subtiI is only), but in all other assays, produced no activity (Table IV). Increased mitotic recombination was induced by azinphos-methyI, crotoxyphos, cacodylic acid, and parathion-methyl in cerevisiae D3 disulfoton enhanced UDS in WI-38 cells. As shown in Table V, however, these pesticides produced no other effects. Bromacil and simazine were positive only in the Drosophila sex-linked recessive lethal test (Table VI). 

Our early work with dinoseb, a nitrophenolic herbicide commonly found as a soil contaminant, showed that under microaerophilic conditions, it is transformed to persistent multimeric forms that remain toxic, while under well-aerated conditions, no degradation occurs (29). However, in studies pre-dating our munitions work, we enriched an anaerobic consortium that fermented dinoseb and other nitroaromatic compounds under methanogenic conditions (16, 17). These initial observations ultimately led to our treatment of soils containing complex mixtures of TNT, dinitrotoluenes, mononitrotoluenes, nitrobenzoates, and related compounds (33), which showed that all contaminants could be removed to below detection limits of gas chromatography/mass-spectrometry. Even though biological treatment of several of these compounds in well-aerated cultures has been described, many of them are subject to polymerization reactions under microaerophilic conditions, which are almost certain to occur in soil treatment systems that are not maintained absolutely anoxic (18). 

---