Trifenmorph

LC50; Species: /Oncorhynchus mykiss/ (Rainbow trout) yearling; Concentration: 0.1 mg/L for 96 hr, pH 6.9-7.0 /Conditions of bioassay not specified in source examined/ /16.5% emulsifiable concentrate/

LC50; Species: /Oncorhynchus mykiss/ (Rainbow trout) yearling; Concentration: 0.52 mg/L for 96 hr, pH 6.9-7.0, hard water /Conditions of bioassay not specified in source examined/ /16.5% Emulsifiable concentrate/

LC50; Species: /Oncorhynchus mykiss/ (Rainbow trout) yearling; Concentration: 1.5 mg/L for 96 hr, pH 6.9-7.0, hard water /Conditions of bioassay not specified in source examined/ /50% paste/

LC50; Species: /Oncorhynchus mykiss/ (Rainbow trout) yearling; Concentration: 0.08 mg/L for 96 hr, pH 6.9-7.0 /Conditions of bioassay not specified in source examined/ /50% paste/

For more Ecotoxicity Values (Complete) data for Trifenmorph (17 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 3.7X10+5(SRC), determined from a structure estimation method(2), indicates that trifenmorph is expected to be immobile in soil(SRC). Volatilization of trifenmorph from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 1.3X10-10 atm-cu m/mole(SRC), using a fragment constant estimation method(3). Trifenmorph is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 2.8X10-8 mm Hg at 25 °C(SRC), determined from a fragment constant method(4). In soil within a few weeks, trifenmorph is aerobically converted to triphenyl methanol which undergoes slow hydroxylation(5).

TERRESTRIAL FATE: Half of N-tritylmorpholine applied to soil was lost in 1 to 4 weeks.

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 3.7X10+5(SRC), determined from a structure estimation method(2), indicates that trifenmorph is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 1.3X10-10 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). According to a classification scheme(5), an estimated BCF of 280(SRC), from an estimated log Kow of 4.21(2) and a regression-derived equation(6), suggests the potential for bioconcentration in aquatic organisms is high(SRC). Under mild acid conditions, trifenmorph is hydrolyzed to morpholine and triphenylmethanol(3). Biodegradation is not an important environmental fate process in water(SRC) based on the slow rate reported for soil(7).

AQUATIC FATE: The fate of the molluscicide trifenmorph (N-tritylmorpholine) following its use in irrigation systems to control the intermediate hosts of schistosomes was studied by laboratory and field experiments. Laboratory studies with 14C-trifenmorph indicated that bean plants did not take up detectable residues when the soil in which they were grown was irrigated with water containing trifenmorph in concentrations likely to occur in the field. These laboratory studies have been complemented by field irrigation studies of growing crops in southern Africa and the Sudan. Residues of trifenmorph and its breakdown product triphenylmethanol could not be detected in the crops and the limit of detectability was 0.01-0.02 ppm. These results indicate that residues are not likely to be present in irrigated crops following the treatment of the irrigation water systems with trifenmorph(1).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), trifenmorph, which has an estimated vapor pressure of 2.8X10-8 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase trifenmorph is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 2.5 hours(SRC), calculated from its rate constant of 1.5X10-10 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase trifenmorph may be removed from the air by wet or dry deposition(SRC). Slight decomposition occurs in UV light(4).

/AQUATIC SPECIES/ Fish were killed in canals treated for 6 hr with frescon to yield concentration of 0.1 ppm.

/AQUATIC SPECIES/ ... Aquatic micro-flora and -fauna were uneffected at 0.2 ppm.

/AQUATIC SPECIES/ /Trifenmorph/ above 0.03 ppm /may be/ harmful to fish.

/OTHER TOXICITY INFORMATION/ /N-tritylmorpholine/ is highly specific, being harmless to plants, insects, and most vertebrates, though it is moderately toxic to some species of fish.

Using a structure estimation method based on molecular connectivity indices(1), the Koc of trifenmorph can be estimated to be 3.7X10+5(SRC). According to a classification scheme(2), this estimated Koc value suggests that trifenmorph is expected to be immobile in soil.

KOC = 37,500 (calculated from water solubility by regression equations). /From table/

An estimated BCF of 280 was calculated in fish for trifenmorph(SRC), using an estimated log Kow of 4.21(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is high(SRC).

Sarotherodon mossambicus /Mozambique talapia/, juvenile, exhibited a bioconcentration factor of 1,300 after 55 hr.

Bioconcentration factor = 5,600 (calculated from water solubility by regression equations). /From table/

The Henry's Law constant for trifenmorph is estimated as 1.3X10-10 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that trifenmorph is expected to be essentially nonvolatile from water and moist soil surfaces(2). Trifenmorph is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 2.8X10-8 mm Hg(SRC), determined from a fragment constant method(3).

/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ The mammalian and avian toxicities of N-tritylmorpholine (Frescon, WL 8008), a compound active against the snails that are the intermediate hosts of schistosomes, are reported. ... Administered percutaneously to rats, N-tritylmorpholine produced no ill-effects at 1000 mg/kg. N-Tritylmorpholine fed in the diets of rats at 100 ppm for 90 days produced no significant effect. ...

/GENOTOXICITY/ Trifenmorph was not mutagenically active in a microbial Ames test.

The rate constant for the vapor-phase reaction of trifenmorph with photochemically-produced hydroxyl radicals has been estimated as 1.5X10-10 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 2.5 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The rate of hydrolysis of 14C-trifenmorph is dependent on the pH of the water (relatively high at low pH values of <7.0) and concentration of the compound(2). Under mild acidic conditions, trifenmorph is hydrolyzed to morpholine and triphenylmethanol(4). Mud and sediment gradually adsorb trifenmorph and carbinol(3). Slight decomposition occurs in UV light(3).

The rate of hydrolysis of 14C-trifenmorph is dependent on the pH of the water (relatively high at low pH values of <7.0) and concentration of the compound(1).