Carp molinate

In the presence of carp, molinate was rapidly transformed into more polar metabolites. Twenty-four hours after treatment, conversion of molinate to organosoluble metabolites was extensive (Table II). The proportion of molinate sulfoxide increased from 1.2% on day 1 to 10.2% by the 14th day. Molinate, hydroxylated at the 4 position, decreased from 10.8% to 4.6% in 14 days. However, 4-keto and 3-hydroxy molinate together gradually increased over the 14 days from 6.9% to 77.7%. Another metabolite, a keto HMI,... 

Metabolism of the Thiocarbamate Herbicide Molinate (Ordram) in Japanese Carp... 

Molinate (S-ethyl hexahydro-azepine-l-carbothioate) has been widely used for broadleaf and grass weed control in rice culture. The 96-hour LC50 of technical molinate in the common goldfish is 30 ppm (1) and the medium tolerance limits (LTm) for molinate in mosquito fish (Gambusia affinis) are 16.4 ppm for 96 hours (J2). Kawatsu (3) estimated the 20-day lethal concentration of molinate in Japanese carp (Cyprinus carpio) var. Yamato koi at 0.18 ppm. However, there was no toxic effect of molinate on American carp at concentrations of 10 ppm during a two-week observation (40. ... 

The purpose of this study was to investigate the extent of accumulation and the fate of molinate in the Japanese carp. 

Table II. Distribution of 14C in Chloroform Extracts of Water Treated with [Ring-14C]-Molinate and Containing Carp...

Figure 1 shows the rapid disappearance of molinate in water containing carp. The data indicate that the fish are largely responsible for molinate biotransformation and/or biodegradation. 

The flesh remaining after removal of the organs listed in Table III also contained very low 1I C residues. In general, accumulation of molinate in carp was extremely low as compared with DDT which has been reported to have a fish bioaccumulation factor of... 

Molinate Metabolism in Carp Hepatic Mixed-function Oxidase System. Incubation of molinate with carp liver microsomes produced four major organosoluble metabolites (molinate sulfoxide, 3- and 4-hydroxy molinate, and keto HMI). Parameters affecting... 

Figure 1. Molinate concentration in the chloroform extract of water with and without carp (A) expressed as percent 14C molinate in the chloroform extract at each interval (B) water contained fish 14 days prior to addition of molinate. The fish were removed at the time of addition of the molinate.

Figure 2. Percent water-soluble uC-labeled metabolites of molinate in the water with and without carp (water-soluble metabolites are defined as those which did not extract with chloroform under the conditions described in Materials and...

Table III. Residues of Radiocarbon in Tissue of Javanese Carp Exposed to Watef1 Containing 0.2 ppm [Ring-,4C]-Molinate...

Figure 3. Effect of temperature on conversion of molinate to its sulfoxide by carp liver microsomal mfo (liver microsomal protein 6 mg/mL, pH 7.4, NADPH 3 mg incubated for 15 min)...

Figure 6. Chromatographic pattern for carp liver microsomal 14C-labeled organo-soluble metabolites of [ring-14C]-molinate. Incubation was conducted under standard conditions for one hr m number represents metabolite code.

Figure 10. Chromatographic pattern for organosoluble uC-labeled metabolites from [ring-14C]-molinate-treated water which contained carp for 4 days. F number represents metabolite code.

Figure 14. Proposed metabolism of [ring-14C]-molinate by carp in vitro and in...

The fate of the herbicide, molinate, in Japanese carp, (Cyprinus carpio) var. Yamato koi, was investigated. [Ring-1 2 3 4 5 6 7 8 9 Cjmolinate was applied to the water at... 

Tjeerdema, R.S. and D.G. Crosby. Comparative biotransformation of molinate (Ordram) in the white sturgeon (Acipenser transmontanus) and common carp (Cyprinus carpio). Xenobiotica 18 831-838, 1988. 

Modification of the Toxicity of Pesticides with Formulation Additives. Potentially the use of additives to modulate the toxicity of pesticides could lead to a considerable increase in their safety to non-target species, man included. This concept has been well explored and exploited in adding safeners to certain herbicides such as the thiocarbamates. These compounds stimulate defensive metabolic reactions in the crop species but not in weeds This principle has also been applied to vertebrates, but only to a very limited degree. Under some circumstances the thiocarbamate rice herbicide, molinate, may show toxicity to carp in nearby ponds. Based on a knowledge of the safeners that are active in plants, a compound was discovered that, when applied with molinate, acted as an antidote/safener for the carp (20). Little effort, either theoretical or empirical, seems to have gone into developing other such examples. 

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