Cyanguanidin

Fresh air, rest.

Rinse skin with plenty of water or shower.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Rinse mouth. Give one or two glasses of water to drink.

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

120 [mg/m3]

1300 [mg/m3]

7900 [mg/m3]

TERRESTRIAL FATE: Based on a recommended classification scheme(1), an estimated Koc value of 6(SRC), determined from an experimental log Kow of -1.15(2) and a recommended regression-derived equation(3), indicates that cyanoguanidine may have very high mobility in soil(SRC). However, when leaching of cyanoguanidine was measured under simulated groundwater conditions (silty loam, pH 6.5) in lysimeters; only 0.6-0.9% of the applied cyanoguanidine was leached over a 5 year period(4); loss was most likely due to biodegradation(SRC). Biodegradation of this compound may be an important fate process in soil under both aerobic and anaerobic conditions(SRC). Mineralization under aerobic conditions was correlated with soil pH but not with organic matter content or total nitrogen(5). In near-neutral soil (pH = 6.8), 10.2 and 41.6% of the added cyanoguanidine-N was mineralized after 12 and 60 days, respectively(5). In other more acidic soils (pH = 4.0-4.3), mineralization after 60 days was only 10-25% that of the near neutral soil(5). Volatilization of cyanoguanidine is not expected to be important from moist soil surfaces(SRC) given an estimated Henry's Law constant of 2.3X10-10 atm-cu m/mole(SRC), using a fragment constant estimation method(6).

AQUATIC FATE: Based on a recommended classification scheme(1), an estimated Koc value of 6(SRC), determined from a measured log Kow of -1.15(2) and a recommended regression-derived equation(1), indicates that cyanoguanidine should not adsorb to suspended solids and sediment in water(SRC). Cyanoguanidine is not expected to volatilize from water surfaces(1,SRC) based on an estimated Henry's Law constant of 2.3X10-10 atm-cu m/mole(SRC), developed using a fragment constant estimation method(3). According to a classification scheme(4), BCF values of <0.3 and <3.1(5), measured in carp, suggest that bioconcentration in aquatic organisms is low(SRC). Biodegradation of this compound may occur in water under both aerobic and anaerobic conditions(SRC). Cyanoguanidine, added to flooded sediments, was completely degraded under aerobic conditions within 34-44 weeks, while under anaerobic conditions two-thirds of the initial concentration was degraded within 60 weeks(6).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), cyanoguanidine, which has an estimated vapor pressure of 1.7X10-3 mm Hg at 25 °C(2,SRC), will exist solely as a vapor in the ambient atmosphere. Vapor-phase cyanoguanidine 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 about 9 hours(3,SRC).

The Koc of cyanoguanidine is estimated as approximately 6(SRC), using a measured log Kow of -1.15(1) and a regression-derived equation(2,SRC). According to a recommended classification scheme(3), this estimated Koc value suggests that cyanoguanidine has very high mobility in soil(SRC). However, when leaching of cyanoguanidine following mineral fertilization, slurry manuring and decomposition under simulated ground water conditions (silty loam, pH 6.5) was measured in lysimeters(4). After mineral feeding, only 0.6-0.9% of the cyanoguanidine applied in 5 years was leached with the highest leaching rate occurring in October (with 5.6% leached of the added amount)(4).

British Industrial Biological Research Association; Toxicity Profile of Dicyandiamide (1988). Dicyandiamide did not ... induce sensitization when applied to skin of volunteers. ...

After 4 yr employment in a factory manufacturing flame retardants, a 29 yr old man developed eczematous reactions on both hands. Patch tests performed with different agents handled by the patient solely at his place of work were positive for the flame retardant and dicyanodiamide, even in high dilutions. Upon changing /positions/, the lesions healed completely. ...

Cyanoguanidine's production and use in the manufacture of fertilizers, pharmaceuticals, plastics, dye-stuffs, explosives, as a catalyst for epoxy resins, a fire-proofing compound, a stabilizer in detergent compositions, an inhibitor of rancidity in fats and oils, a thinner for oil-well drilling muds(1) and as a paint ingredient(2) may result in its release to the environment through various waste streams(SRC). Cyanoguanidine may be formed during the sewage treatment of nitroguanidine due to abiotic processes(3).

Cyanoguanidine, at 30 mg/l, reached only 2.2% of the theoretical BOD in two weeks using a sludge inoculum(1). Biodegradation of cyanoguanidine was measured in six soils, five collected from Sri Lankan tea plantations and one grassland soil from Highfield, UK; in the near-neutral Highfield soil (pH = 6.8), 10.2 and 41.6% of the cyanoguanidine-N was mineralized after 12 and 60 days, respectively(2). In the other, more acidic soils (pH = 4.0-4.3), only a small percentage of the added cyanoguanidine-N was mineralized to ammonia and nitrate nitrogen; mineralization after 60 days was only 10-25% that of the Highland soil(2). Mineralization was correlated with soil pH but not with organic matter content or total nitrogen(2). Cyanoguanidine, at 20 mg/l was added to flooded sediments; complete degradation was reported within 34-44 weeks for aerobic conditions, while under anaerobic conditions two-thirds of the initial concentration was degraded within 60 weeks(3).

The Henry's Law constant for cyanoguanidine is estimated as 2.3X10-10 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This value indicates that cyanoguanidine will be essentially nonvolatile from water surfaces(2,SRC). Cyanoguanidine's Henry's Law constant(1,SRC) indicates that volatilization from moist soil surfaces should not occur(SRC).

RELATIVE TOXICITY OF DICYANDIAMIDE TO SOYBEAN SEEDLINGS. TOXICITY APPEARED AS CHLOROSIS OF OLDER LEAVES & NECROTIC PATCHES ON LEAF MARGINS. RESTRICTION IN ROOT GROWTH & SUPPRESSION OF FRESH & DRY WT WAS MOST CHARACTERISTIC OF DICYANDIAMIDE TOXICITIES.

... The oral LD50 in mice /was found/ to be greater than 4 g/kg when given with alcohol, and greater than 3 g/kg in rabbits.

A 13-week subchronic oral toxicity study of cyanoguanidine was performed in male and female F344 rats by feeding of CRFl powder diets containing 0, 1.25, 2.5, 5 and 10% cyanoguanidine to determine appropriate dose levels for a subsequent 2 year carcinogenicity study. The rats were randomly allocated to 5 groups, each consisting of 10 males and 10 females. No animals died during the administration period. Inhibition of body weight gain was more marked in both sexes of the 10% group and in females of the 5% group as compared with the control group. Mean food intake in males of the groups treated with 5% or 10% and in females of the 10% group was significantly higher than that in the control group. Serum biochemical investigation revealed a higher level of serum BUN in both sexes of the 10% group. On histopathological examination, toxic changes characterized by the occurrence of intranuclear eosinophilic inclusion bodies in the proximal tubular epithelium of the kidney were observed in both sexes of the 10% group. Similar inclusion bodies were also seen in 2 out of 10 females of the 5% group. From these results, it was concluded that a level of 10% of cyanoguanidine in the diet is unequivocally toxic. A dose level, 5% cyanoguanidine, in the diet might be appropriate as a high dose for a carcinogenicity study.

The mutagenic activity of ... /cyanoguanidine/ was tested in reversion mutagenicity assays with a set of histidine auxotrophic strains of Salmonella typhimurium by means of the preincubation method. A possible metabolic activation of the substances by cell free fractions from maize seedlings (S-14 fraction) and for comparison from mouse liver (S-9 mix) was examined. ... Cyanoguanine ... became mutagenic for Salmonella strain TA98 after metabolic activation by the S-14 plant mixture. /Cyanoguanine/ ... was not mutagenic in the presence of S-9 mix made from mouse liver. ...

The rate constant for the vapor-phase reaction of cyanoguanidine with photochemically-produced hydroxyl radicals has been estimated as 4.2X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1,SRC). This corresponds to an atmospheric half-life of about 9 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1,SRC).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 28,806 workers (5810 of these are female) are potentially exposed to cyanoguanidine in the US(1). Occupational exposure may be through inhalation and dermal contact with this compound at workplaces where cyanoguanidine is produced or used. The general population may be exposed to cyanoguanidine via dermal contact with products containing cyanoguanidine(SRC).