dibutyltin dilaurate

H341: Suspected of causing genetic defects [Warning Germ cell mutagenicity]

H360FD: May damage fertility; May damage the unborn child [Danger Reproductive toxicity]

H372: Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure]

P203, P260, P264, P270, P280, P318, P319, P405, and P501 (click each P-code to see the statement)

P203, P280, P318, P405, and P501 (click each P-code to see the statement)

H301: Toxic if swallowed [Danger Acute toxicity, oral]

H315: Causes skin irritation [Warning Skin corrosion/irritation]

H319: Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H330: Fatal if inhaled [Danger Acute toxicity, inhalation]

H360: May damage fertility or the unborn child [Danger Reproductive toxicity]

H400: Very toxic to aquatic life [Warning Hazardous to the aquatic environment, acute hazard]

H410: Very toxic to aquatic life with long lasting effects [Warning Hazardous to the aquatic environment, long-term hazard]

P203, P260, P264, P264+P265, P270, P271, P273, P280, P284, P301+P316, P302+P352, P304+P340, P305+P351+P338, P316, P318, P319, P320, P321, P330, P332+P317, P337+P317, P362+P364, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

H314: Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]

P203, P260, P264, P270, P271, P280, P284, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P318, P319, P320, P321, P363, P403+P233, P405, and P501 (click each P-code to see the statement)

Fresh air, rest.

Wear protective gloves when administering first aid. Remove contaminated clothes. Rinse and then wash skin with water and soap.

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

Rinse mouth.

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.

INGESTION: Some heavy metals are VERY TOXIC POISONS, especially if their salts are very soluble in water (e.g., lead, chromium, mercury, bismuth, osmium, and arsenic). IMMEDIATELY call a hospital or poison control center and locate activated charcoal, egg whites, or milk in case the medical advisor recommends administering one of them. Also locate Ipecac syrup or a glass of salt water in case the medical advisor recommends inducing vomiting. Usually, this is NOT RECOMMENDED outside of a physician's care. If advice from a physician is not readily available and the victim is conscious and not convulsing, give the victim a glass of activated charcoal slurry in water or, if this is not available, a glass of milk, or beaten egg whites and IMMEDIATELY transport victim to a hospital. If the victim is convulsing or unconscious, do not give anything by mouth, assure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital. (NTP, 1992)

Fires involving this compound should be controlled using a dry chemical, carbon dioxide or Halon extinguisher. (NTP, 1992)

Use water spray, powder, alcohol-resistant foam, carbon dioxide.

Excerpt from ERG Guide 153 [Substances - Toxic and/or Corrosive (Combustible)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.

FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)

Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Collect leaking and spilled liquid in sealable containers as far as possible. Sweep spilled substance into covered containers. If appropriate, moisten first to prevent dusting. Carefully collect remainder. Then store and dispose of according to local regulations. Do NOT let this chemical enter the environment.

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.

Avoid the vapor produced by heating.

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

SMALL SPILLS AND LEAKAGE: If you spill this chemical, use absorbent paper to pick up all liquid spill material. Your contaminated clothing and absorbent paper should be sealed in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with alcohol followed by washing with a strong soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

STORAGE PRECAUTIONS: You should store this material in a refrigerator. (NTP, 1992)

Store in an area without drain or sewer access.

0.02 [mg/m3], inhalable fraction, as Sn[German Research Foundation (DFG)]

1.1 [mg/m3]

3.8 [mg/m3]

23 [mg/m3]

0.1 [mg/m3], as Sn

25.0 [mg/m3], as Sn

0.2 [mg/m3], as Sn

8 hr Time Weighted Avg (TWA): 0.1 mg/cu m; 15 min Short Term Exposure Limit (STEL): 0.2 mg/cu m, skin. /Tin, organic cmpd, as Sn/

A4; Not classifiable as a human carcinogen. /Tin, organic compounds, as Sn/

(as Sn): 0.1 mg/m

(as Sn): 0.02 mg/m

A harmful contamination of the air will not or will only very slowly be reached on evaporation of this substance at 20 °C.

The substance is irritating to the eyes and skin.

The substance may have effects on the liver, kidneys, gastrointestinal tract and immune system. May cause toxicity to human reproduction or development. May cause heritable genetic damage to human germ cells.

Dibutyltin dilaurate is exempted from the requirement of a tolerance when used as a component of plastic slow release tag in accordance with good agricultural practice as inert (or occasionally active) ingredients in pesticide formulations applied to animals.

RECOMMENDED RESPIRATOR: Where the neat test chemical is weighed and diluted, wear a NIOSH-approved half face respirator equipped with an organic vapor/acid gas cartridge (specific for organic vapors, HCl, acid gas and SO2) with a dust/mist filter. (NTP, 1992)

NO open flames.

AVOID ALL CONTACT!

Use ventilation.

Protective gloves.

Wear safety spectacles.

Do not eat, drink, or smoke during work.

Dibutyltin dilaurate is a clear yellow viscous liquid. (NTP, 1992)

Liquid; CBI

Soft solid or yellow liquid; mp = 22-24 deg C; [Merck Index] Yellow oily liquid or waxy solid; [ICSC] Yellow viscous liquid; [MSDSonline]

YELLOW OILY LIQUID OR WAXY CRYSTALS.

Soft crystals or yellow liquid

Oily liquid

205 °C at 1.3 kPa (to convert kPa to mm Hg, multiply by 7.5)

at 1.3kPa: 205 °C

72 to 75 °F (NTP, 1992)

22-24 °C

446 °F (NTP, 1992)

455 °F (open cup)

less than 1 mg/mL at 68 °F (NTP, 1992)

Practically insol in methanol; sol in petroleum ether, benzene, acetone, ether, carbon tetrachloride, organic esters

In water, 3 ppm @ room temperature.

Solubility in water: none

1.066 at 68 °F (NTP, 1992) - Denser than water; will sink

1.05 g/cu cm @ 20 °C

Density (at 20 °C): 1.05 g/cm³

1.06 @ 20°C

21.8 (NTP, 1992) - Heavier than air; will sink (Relative to Air)

21.8 (Air = 1)

negligible

log Kow= 3.12

It lacks any great stability at high temperatures.

When heated to decomposition it emits acrid smoke and fumes.

42 cP at 25 °C

Index of refraction: 1.4683 at 20 °C/D (for product made under French patent 1,320,473)

Metals -> Tin Compounds, Organic

FCS -> FDA Inventory of Food Contact Substances Listed in 21 CFR

Plastics -> Polyolefin-I; PVC (soft); PVC (rigid)

Plastics -> Heat stabilisers

This compound may be sensitive to air or heat. (NTP, 1992). Insoluble in water.

Salts, Basic

Organometallics

DIBUTYLTIN DILAURATE is strongly reactive with many other groups. Incompatible with acids and bases. Organometallics are good reducing agents and therefore incompatible with oxidizing agents.

... Reacts with oxidizers.

Organotin compounds produce neurotoxic and immunotoxic effects. Organotins may directly activate glial cells contributing to neuronal cell degeneration by local release of pro-inflammatory cytokines, tumor necrosis factor-_, and/or interleukins. They may also induce apoptosis by direct action on neuronal cells. Organotin compounds stimulate the neuronal release of and/or decrease of neuronal cell uptake of neurotransmitters in brain tissue, including aspartate, GABA, glutamate, norepinephrine, and serotonin. This may be either a contributing factor to or result of the neuronal cell loss. The immunotoxic effects of organotins are characterized by thymic atrophy caused by the suppression of proliferation of immature thymocytes and apoptosis of mature thymocytes. Organotin compounds are believed to exert these effects by suppressing DNA and protein synthesis, inducing the expression of genes involved in apoptosis (such as nur77), and disrupting the regulation of intracellular calcium levels, giving rise to the uncontrolled production of reactive oxygen species, release of cytochrome c to the cytosol, and the proteolytic and nucleolytic cascade of apoptosis. The suppression of proliferation of immature thymocytes further results in the suppression of T-cell-mediated immune responses. Organotins are also endocrine disruptors and are believed to contribute to obesity by inappropriate receptor activation, leading to adipocyte differentiation. Inorganic tin triggers eryptosis, contributing to tin-induced anemia. (L308, A182, A184)

A4; Not classifiable as a human carcinogen. /Tin, organic compounds, as Sn/

No indication of carcinogenicity to humans (not listed by IARC).

Breathing or swallowing, or skin contact with organotins, can interfere with the way the brain and nervous system work, causing death in severe cases. Organic tin compounds may also damage the immune and reproductive system. (L307, L308)

The substance can be absorbed into the body by ingestion and through the skin.

Oral (L308) ; inhalation (L308) ; dermal (L308)

Redness. MAY BE ABSORBED!

Redness.

Inorganic or organic tin compounds placed on the skin or in the eyes can produce skin and eye irritation. (L308)

Neurotoxin - Other CNS neurotoxin

Occupational hepatotoxin - Secondary hepatotoxins: the potential for toxic effect in the occupational setting is based on cases of poisoning by human ingestion or animal experimentation.

ACGIH Carcinogen - Not Classifiable.

LC50 (rat) = 150 mg/m3/2h

LD50: 175 mg/kg (Oral, Rat) (T21)

LD50: 85 mg/kg (Intraperitoneal, Rat) (T21)

LD50 Rat male oral 175 mg/kg (oil solution)

LD50 Rat intraperitoneal 85 mg/kg

Irritant dose rabbit dermal 500 mg/24 hr; irritant effects: moderate skin irritation

Irritant dose rabbit ocular 100 mg/24 hr; irritant effects: moderate eye irritation

DIBUTYLTIN DILAURATE (DBDL) 15-40 MG/KG WAS ADMIN ORALLY TO RABBITS FOR 6 WK (6 DAYS/WK). SERUM GLUTAMATE-OXALACETATE TRANSAMINASE, GLUTAMATE-PYRUVATE TRANSAMINASE & LACTATE DEHYDROGENASE WERE INCR IN ANIMALS INDICATING LIVER DAMAGE. SERUM ALKALINE PHOSPHATASE REMAINED ALMOST UNCHANGED. SERUM TRIGLYCERIDES, PHOSPHOLIPIDS, FREE FATTY ACIDS, BETA-LIPOPROTEIN, TOTAL CHOLESTEROL, & FREE CHOLESTEROL WERE INCREASED.

POISONING CAUSED BY DIBUTYLTIN DILAURATE WAS DIAGNOSED IN CATTLE, MINK, & PALM DOVES (STREPTOPELIA SENEGALENSIS).

Dibutyltin laurate .. was inadvertently mixed with cattle food. This caused a large number of deaths. ... Calves died at the acute stage with tremors, convulsions, general weakness & diarrhea. The chronic signs were persistent diarrhea, severe wt loss, inappetence, polyuria & depression.

Dibutyltin dilaurate was evaluated for mutagenicity in the Salmonella/microsome preincubation assay using a standard protocol approved by the National Toxicology Program. Dibutyltin dilaurate was tested at doses of 0, 1, 3, 10, 33, 100, and 166 ug/plate in four Salmonella typhimurium strains (TA98, TA100, TA1535, and TA1537) in the presence and absence of Aroclor-induced rat or hamster liver S9. Dibutyltin dilaurate was negative in these tests and the highest ineffective dose level tested in any Salmonella tester strain was 166 ug/plate.

For more Non-Human Toxicity Excerpts (Complete) data for DIBUTYLTIN DILAURATE (7 total), please visit the HSDB record page.

Antifertility activity was evaluated in three pairs of one male and one female Cox-Swiss white mice ingesting 0.01% by weight of dibutyltin dilaurate in the basal diet. At the start of the test, male and female rats were exposed to the standard basal diet and allowed to mate (pre-treatment control). Male and female mice were separated and exposed to the test substance for 4 days, after which they were returned to their mates and maintained on the treatment for 14 days. Females showing signs of pregnancy during the 14 day period were separated and placed on the standard diet and allowed to proceed to term. One treated female mouse had a slightly longer parturition time, which was statistically significant compared to the pre-treatment data. No effect on fertility was observed for any of the treatment groups and none of the offspring had any morphological abnormalities.

The fate of dibutyltin dilurate was evaluated in male albino (strain not reported) rats (10/exposure) receiving the test material at 0.1, 0.024, 0.006, 0.0015 and 0% in the diet for 30 days. Urine, blood and organs were quantitatively analyzed for tin by spectrographic technique. The small quantities of tin in the organs and urine suggest that the majority of tin is eliminated without absorption through the digestive tract. The liver and kidneys of rats at the highest dose (0.1%) contain approximately two-thirds of the diet consumed in one day and urine contained about one-hundredth of the tin they ingested.

The substance is toxic to aquatic organisms. The substance may cause long-term effects in the aquatic environment. Avoid release to the environment in circumstances different to normal use.

Dibutyltin dilaurate's production and use as a stabilizer for vinyl resins, poly(vinyl chloride), lacquers, and elastomers, and as a catalyst for polyurethanes and silicones may result in its release to the environment through various waste streams. Also, dibutyltin is formed as a degradation product of tributyltin, an antifouling agent used in marine paint. If released to air, an estimated vapor pressure of 4.5X10-9 mm Hg at 25 °C indicates dibutyltin dilaurate will exist solely in the particulate phase in the ambient atmosphere. Particulate-phase dibutyltin dilaurate will be removed from the atmosphere by wet and dry deposition. In soil and water, dibutyltin dilaurate may dissociate forming the cation, dibutyltin. If released to soil, dibutyltin is expected to adsorb to organic carbon and clay. Volatilization from moist soil surfaces is not expected to be an important fate process because the cation will not volatilize. Dibutyltin dilaurate may also biodegrade in soil and water since tributyltins are converted to dibutyltin and monobutyltin. If released into water, dibutyltin is expected to adsorb to suspended solids and sediment. Volatilization from water surfaces will not be an important fate process because the cation will not volatilize. A BCF of 31 suggests the potential for bioconcentration in aquatic organisms is low. Occupational exposure to dibutyltin dilaurate may occur through dermal contact with this compound at workplaces where dibutyltin dilaurate is produced or used. Monitoring data indicate that the general population may be exposed to dibutyltin via ingestion of food and drinking water, but this may or may not be due to the dilaurate. (SRC)

Dibutyltin dilaurate's production and use as a stabilizer for vinyl resins, poly(vinyl chloride), lacquers, and elastomers, and as a catalyst for polyurethanes and silicones(1) may result in its release to the environment through various waste streams(SRC). Dibutyltin is formed as a degradation product of tributyltin, an antifouling agent used in marine paint(2).

The final degradation products of organotins are believed to consist of inorganic salts. /Organotin compounds/

TERRESTRIAL FATE: Dibutyltin dilaurate is expected to dissociate in soil forming the cation, dibutyltin(SRC). Dibutyltin is expected to adsorb to organic carbon and clay(SRC). Volatilization from moist soil surfaces is not expected to be an important fate process because the cation is not expected to volatilize(SRC). Dibutyltin dilaurate may also biodegrade in soil, since tributyltins are converted to dibutyltin and monobutyltin(1).

AQUATIC FATE: Dibutyltin dilaurate is expected to dissociate in water forming the cation, dibutyltin(SRC). Cations generally adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected to be an important fate process because the cation is not expected to volatilize(SRC). Dibutyltin dilaurate may also biodegrade in soil(1). According to a classification scheme(2), a BCF value of 31(3) suggests the potential for bioconcentration in aquatic organisms is low(SRC). Tributyltin species in water are sequentially degraded to dibutyltin, monobutyltin, and finally to inorganic tin in water/sediment mixtures or water alone from Toronto Harbor, Canada(4). Small quantities of dimethyldibutyltin were occasionally detected in these experiments in water/sediment and water alone, but not in the sterile controls, which indicates the possibility of biomethylation of dibutyltin compounds(4).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), dibutyltin dilaurate, which has an estimated vapor pressure of 4.5X10-9 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely in the particulate phase in the ambient atmosphere. Particulate-phase dibutyltin dilaurate may be removed from the air by wet and dry deposition(SRC).

The tributytin species obtained by dissolution of tributyltin oxide in water are sequentially biodegraded to dibutyltin species, monobutyltin species, and finally to inorganic tin in water/sediment mixtures or water alone from Toronto Harbor(1). Small quantities of dimethyldibutyltin were occasionally detected in these experiments in water/sediment and water alone which indicates the possibility of biomethylation of dibutyltin compounds(1).

Dibutyltin compounds such as dibutyltin dilaurate in environmental waters probably either exist as or will rapidly be converted to dibutyltin oxides, hydroxides, carbonates, or hydrated cations(3). Dibutyltin cation may react with water and behave like a simple protic acid due to the resulting formation of hydronium ion and either dibutyltin dihydroxide or other dibutyltin-hydroxide species at concn above approx 1X10-5 M, based upon the behavior of dimethyltin dication(2). In seawater, the chloride ion may compete effectively with hydroxide ions and stabilize the presence of mono-n-butyltin trichloride in solution(2). Dissociation and speciation of dibutyltin dilaurate in the environment may affect its fate and transport processes(SRC). Dibutyltin compounds may react with sulfides present in sediment, leading to the formation of dibutyltin sulfide(3). Dibutyltins are degraded by UV radiation yielding inorganic tin as a final product(1). Dibutyltin dilaurate may be susceptible to photooxidation by photochemically produced hydroxyl radicals in the atmosphere(SRC).

The observed BCF for dibutyltin dilaurate in round crucian carp (Carassius carassius grandoculis) muscle, vertebra, liver, and kidney tissue were 31, 54, 813, and 138, respectively(1). According to a classification scheme(2), a BCF value of 31(1) suggests bioconcentration in aquatic organisms is low(SRC).

Dibutyltin dilaurate is expected to hydrolyze in water forming the cation, dibutyltin(SRC). Cations generally adsorb to organic carbon and clay; therefore, dibutyltin may be expected to have limited mobility in soil(SRC). In a 278-day marine mesocosm experiment in which tributyltin was added to the system in summer, the distribution coefficient for dibutyltin between the dissolved state and particulate matter calculated from data between days 2-19 was 30,000 (standard deviation 20,000)(1). Other investigators obtained distribution constants for adsorption of dibutyltin to particulate matter and sediment of 600 l/kg and 700-26,000 l/kg, respectively; values were a function of sediment type and location(1). The Freundlich parameters, log k and 1/n, for dibutyl tin to sediment was 1.33 and 0.969, respectively(2). In a study of desorption from sediment, approximately 1% of the initial dibutyltin species was observed to desorb from the unshaken Toronto Harbor sediment/water mixtures in 10.6 months(3).

Dibutyltin dilaurate is expected to dissociate in water forming the cation, dibutyltin(SRC). Volatilization from moist soil and water surfaces is not expected to be an important fate process because the cation is not expected to volatilize(SRC). Dibutyltin dilaurate is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 4.5X10-9 mm Hg(SRC), determined from a fragment constant method(1).

SURFACE WATER: The only monitoring data located were for dibutyltin (Bu2Sn++) without regard for the identity of the accompanying anion(s) and concn is often reported in Sn equivalents(1). Dibutyltin was detected and quantified in 26 of 214 samples of unfiltered subsurface water from 209 locations in Canada sampled between 1982- 1985 at concentrations ranging from 0.01 to 1.36 ppb Sn (average concn of pos, quantified samples = 0.12 ppb Sn); dibutyltin also was detected, not quantified in another 21 of the samples (concn range from approx 3.3 parts/trillion Sn (limit of detection) to <0.01 ppb Sn (limit of quantitation))(1). Dibutyltin was detected at one of six sites in New York state at 0.01 ppb Sn, but was not detected in one sample from the Detroit River, MI(1).

SURFACE WATER: The concentration of dibutyltin species in unfiltered subsurface water from Toronto Harbor (7 sites) was trace-0.10 ug Sn/l(1). Dibutyl tin was found in unfiltered subsurface water and unfiltered surface microlayers of various lakes, rivers, and harbors in Ontario at levels ranging from 0.01-7.30 and 0.71-2600 ug/l, respectively, indicating that this species was concentrated by factors of up to 4 orders of magnitude in the microlayer(2). Water samples taken over several months in the Rhine River at Mainz in 1989 reported dibutyltin levels of 0.5-2 ng Sn/l in 13 of 14 samples taken(3). In 4 harbors at Mainz and Wiesbaden, they ranged from 1-16 ng Sn/l. In the Schwarzbach, a tributary of the Rhine near Mainz, dibutyltin levels were 2 ng Sn/l, only slightly lower than that in the effluent of sewage treatment plants(3). This is consistent with the very high input of sewage in this stream. Dibutyltin concns ranged from 13-30 ng Sn/l and 1.6 to 67 ng Sn/l on the Elizabeth River (10 locations) and Sarah Creek (8 locations), both rivers feeding into the lower Chesapeake Bay(3).

SURFACE WATER: The only monitoring data located were for dibutyltin (Bu2Sn++) without regard for the identity of the accompanying anion(s) and concn is often reported in Sn equivalents(1). Dibutyltin was detected and quantified in samples of unfiltered subsurface water from 5 of 6 sites in Toronto Harbor, Ontario at concn ranging from 0.01 to 0.10 ppb Sn (avg concn was 0.04 ppb Sn), and it was detected, not quantified, in the other site in the harbor; dibutyltin was detected, not quantified, in water from 1 of 2 sites outside the harbor(1).

The substance is toxic to aquatic organisms. The substance may cause long-term effects in the aquatic environment. Avoid release to the environment in circumstances different to normal use.

Dibutyltin dilaurate's production and use as a stabilizer for vinyl resins, poly(vinyl chloride), lacquers, and elastomers, and as a catalyst for polyurethanes and silicones may result in its release to the environment through various waste streams. Also, dibutyltin is formed as a degradation product of tributyltin, an antifouling agent used in marine paint. If released to air, an estimated vapor pressure of 4.5X10-9 mm Hg at 25 °C indicates dibutyltin dilaurate will exist solely in the particulate phase in the ambient atmosphere. Particulate-phase dibutyltin dilaurate will be removed from the atmosphere by wet and dry deposition. In soil and water, dibutyltin dilaurate may dissociate forming the cation, dibutyltin. If released to soil, dibutyltin is expected to adsorb to organic carbon and clay. Volatilization from moist soil surfaces is not expected to be an important fate process because the cation will not volatilize. Dibutyltin dilaurate may also biodegrade in soil and water since tributyltins are converted to dibutyltin and monobutyltin. If released into water, dibutyltin is expected to adsorb to suspended solids and sediment. Volatilization from water surfaces will not be an important fate process because the cation will not volatilize. A BCF of 31 suggests the potential for bioconcentration in aquatic organisms is low. Occupational exposure to dibutyltin dilaurate may occur through dermal contact with this compound at workplaces where dibutyltin dilaurate is produced or used. Monitoring data indicate that the general population may be exposed to dibutyltin via ingestion of food and drinking water, but this may or may not be due to the dilaurate. (SRC)

Dibutyltin dilaurate's production and use as a stabilizer for vinyl resins, poly(vinyl chloride), lacquers, and elastomers, and as a catalyst for polyurethanes and silicones(1) may result in its release to the environment through various waste streams(SRC). Dibutyltin is formed as a degradation product of tributyltin, an antifouling agent used in marine paint(2).

The final degradation products of organotins are believed to consist of inorganic salts. /Organotin compounds/

TERRESTRIAL FATE: Dibutyltin dilaurate is expected to dissociate in soil forming the cation, dibutyltin(SRC). Dibutyltin is expected to adsorb to organic carbon and clay(SRC). Volatilization from moist soil surfaces is not expected to be an important fate process because the cation is not expected to volatilize(SRC). Dibutyltin dilaurate may also biodegrade in soil, since tributyltins are converted to dibutyltin and monobutyltin(1).

AQUATIC FATE: Dibutyltin dilaurate is expected to dissociate in water forming the cation, dibutyltin(SRC). Cations generally adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected to be an important fate process because the cation is not expected to volatilize(SRC). Dibutyltin dilaurate may also biodegrade in soil(1). According to a classification scheme(2), a BCF value of 31(3) suggests the potential for bioconcentration in aquatic organisms is low(SRC). Tributyltin species in water are sequentially degraded to dibutyltin, monobutyltin, and finally to inorganic tin in water/sediment mixtures or water alone from Toronto Harbor, Canada(4). Small quantities of dimethyldibutyltin were occasionally detected in these experiments in water/sediment and water alone, but not in the sterile controls, which indicates the possibility of biomethylation of dibutyltin compounds(4).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), dibutyltin dilaurate, which has an estimated vapor pressure of 4.5X10-9 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely in the particulate phase in the ambient atmosphere. Particulate-phase dibutyltin dilaurate may be removed from the air by wet and dry deposition(SRC).

The tributytin species obtained by dissolution of tributyltin oxide in water are sequentially biodegraded to dibutyltin species, monobutyltin species, and finally to inorganic tin in water/sediment mixtures or water alone from Toronto Harbor(1). Small quantities of dimethyldibutyltin were occasionally detected in these experiments in water/sediment and water alone which indicates the possibility of biomethylation of dibutyltin compounds(1).

Dibutyltin compounds such as dibutyltin dilaurate in environmental waters probably either exist as or will rapidly be converted to dibutyltin oxides, hydroxides, carbonates, or hydrated cations(3). Dibutyltin cation may react with water and behave like a simple protic acid due to the resulting formation of hydronium ion and either dibutyltin dihydroxide or other dibutyltin-hydroxide species at concn above approx 1X10-5 M, based upon the behavior of dimethyltin dication(2). In seawater, the chloride ion may compete effectively with hydroxide ions and stabilize the presence of mono-n-butyltin trichloride in solution(2). Dissociation and speciation of dibutyltin dilaurate in the environment may affect its fate and transport processes(SRC). Dibutyltin compounds may react with sulfides present in sediment, leading to the formation of dibutyltin sulfide(3). Dibutyltins are degraded by UV radiation yielding inorganic tin as a final product(1). Dibutyltin dilaurate may be susceptible to photooxidation by photochemically produced hydroxyl radicals in the atmosphere(SRC).

The observed BCF for dibutyltin dilaurate in round crucian carp (Carassius carassius grandoculis) muscle, vertebra, liver, and kidney tissue were 31, 54, 813, and 138, respectively(1). According to a classification scheme(2), a BCF value of 31(1) suggests bioconcentration in aquatic organisms is low(SRC).

Dibutyltin dilaurate is expected to hydrolyze in water forming the cation, dibutyltin(SRC). Cations generally adsorb to organic carbon and clay; therefore, dibutyltin may be expected to have limited mobility in soil(SRC). In a 278-day marine mesocosm experiment in which tributyltin was added to the system in summer, the distribution coefficient for dibutyltin between the dissolved state and particulate matter calculated from data between days 2-19 was 30,000 (standard deviation 20,000)(1). Other investigators obtained distribution constants for adsorption of dibutyltin to particulate matter and sediment of 600 l/kg and 700-26,000 l/kg, respectively; values were a function of sediment type and location(1). The Freundlich parameters, log k and 1/n, for dibutyl tin to sediment was 1.33 and 0.969, respectively(2). In a study of desorption from sediment, approximately 1% of the initial dibutyltin species was observed to desorb from the unshaken Toronto Harbor sediment/water mixtures in 10.6 months(3).

Dibutyltin dilaurate is expected to dissociate in water forming the cation, dibutyltin(SRC). Volatilization from moist soil and water surfaces is not expected to be an important fate process because the cation is not expected to volatilize(SRC). Dibutyltin dilaurate is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 4.5X10-9 mm Hg(SRC), determined from a fragment constant method(1).

SURFACE WATER: The only monitoring data located were for dibutyltin (Bu2Sn++) without regard for the identity of the accompanying anion(s) and concn is often reported in Sn equivalents(1). Dibutyltin was detected and quantified in 26 of 214 samples of unfiltered subsurface water from 209 locations in Canada sampled between 1982- 1985 at concentrations ranging from 0.01 to 1.36 ppb Sn (average concn of pos, quantified samples = 0.12 ppb Sn); dibutyltin also was detected, not quantified in another 21 of the samples (concn range from approx 3.3 parts/trillion Sn (limit of detection) to <0.01 ppb Sn (limit of quantitation))(1). Dibutyltin was detected at one of six sites in New York state at 0.01 ppb Sn, but was not detected in one sample from the Detroit River, MI(1).

SURFACE WATER: The concentration of dibutyltin species in unfiltered subsurface water from Toronto Harbor (7 sites) was trace-0.10 ug Sn/l(1). Dibutyl tin was found in unfiltered subsurface water and unfiltered surface microlayers of various lakes, rivers, and harbors in Ontario at levels ranging from 0.01-7.30 and 0.71-2600 ug/l, respectively, indicating that this species was concentrated by factors of up to 4 orders of magnitude in the microlayer(2). Water samples taken over several months in the Rhine River at Mainz in 1989 reported dibutyltin levels of 0.5-2 ng Sn/l in 13 of 14 samples taken(3). In 4 harbors at Mainz and Wiesbaden, they ranged from 1-16 ng Sn/l. In the Schwarzbach, a tributary of the Rhine near Mainz, dibutyltin levels were 2 ng Sn/l, only slightly lower than that in the effluent of sewage treatment plants(3). This is consistent with the very high input of sewage in this stream. Dibutyltin concns ranged from 13-30 ng Sn/l and 1.6 to 67 ng Sn/l on the Elizabeth River (10 locations) and Sarah Creek (8 locations), both rivers feeding into the lower Chesapeake Bay(3).

SURFACE WATER: The only monitoring data located were for dibutyltin (Bu2Sn++) without regard for the identity of the accompanying anion(s) and concn is often reported in Sn equivalents(1). Dibutyltin was detected and quantified in samples of unfiltered subsurface water from 5 of 6 sites in Toronto Harbor, Ontario at concn ranging from 0.01 to 0.10 ppb Sn (avg concn was 0.04 ppb Sn), and it was detected, not quantified, in the other site in the harbor; dibutyltin was detected, not quantified, in water from 1 of 2 sites outside the harbor(1).

SURFACE WATER: The only monitoring data located were for dibutyltin (Bu2Sn++) without regard for the identity of the accompanying anion(s)(1). Analysis for dibutyltin in samples of unfiltered surface microlayer and subsurface water from Maryland waters of Chesapeake Bay sampled approx monthly between July 1985 to June 1986, gave the following results: four marinas, microlayer, 32 of 44 samples pos, 0.033 to 1.156 ppb, 0.25 ppb avg; subsurface 36 of 48 samples pos, 0.010 to 0.298 ppb, 0.080 ppb avg; Baltimore Harbor, microlayer, 3 of 6 samples pos, 0.017 to 0.035 ppb, 0.026 ppb avg; subsurface, 5 of 12 pos, 0.016 to 0.035 ppb, 0.026 ppb avg; Chesapeake and Delaware Canal (a major shipping canal), microlayer, 3 of 6 samples pos, 0.022 to 1.1 ppb, 0.40 ppb avg; subsurface, 3 of 12 pos, 0.012 to 0.016 ppb; Potomac and Choptank Rivers, microlayer, 1 of 11 pos, 0.029 ppb; subsurface, 3 of 24 pos, 0.020 to 0.022 ppb(1).

SURFACE WATER: The only monitoring data located were for dibutyltin (Bu2Sn++) without regard for the identity of the accompanying anion(s)(1). Dibutyltin was detected in unfiltered surface and bottom water from San Diego Harbor in 28 of 32 samples taken in 1983 through 1985 from 5 stations at concn ranging from 0.01 to 0.46 ppb (0.12 avg concn)(1).

The concn of dibutyltin in the effluent of five municipal sewage treatment plants in Germany ranged from 3-48 ng Sn/l while that of a producer of organotin compounds was 8570 ng Sn/l(1).

SEDIMENT: The only monitoring data located were for dibutyltin (Bu2Sn++) without regard for the identity of the accompanying anion(s) and concn was reported in Sn equivalents(1). Dibutyltin was detected and quantified in 61 of 235 samples of the top 2 cm of sediment from bodies of surface water in Canada sampled between 1982-1985 at concentrations ranging from 0.01 to 8.51 ppm Sn (dry wt) (average concn of pos, quantified samples = 0.49 ppm Sn (dry wt); dibutyltin also was detected, not quantified in another 27 of the samples (concn range from approx >3.3 ppb Sn (dry wt) (limit of detection) to <0.01 ppm Sn (dry wt) (limit of quantitation))(1). Dibutyltin was not detected in sediment from one site in Michigan and six sites in New York state(1).

SEDIMENT: The concentration of dibutyltin species in sediment (upper 2 cm) from Toronto Harbor (5 sites) was 0.01-0.26 mg Sn/kg dry weight(1). The concn of dibutyltin in sediment from two harbors along the Rhine River in Germany were 44 and 15 ng Sn/g dry wt; the high level is from a small harbor that is crowded with pleasure crafts that are believed to be responsible for large releases of tributyltin(2). Sediment from a tributary of the Rhine with a high input of sewage contained 477 ng Sn/g dry wt(2). Intertidal sediments at a restricted site downstream from the shipyards in the Sado estuary, Portugal reached levels of 9600 ng/g dry wt for dibutyltin in July samples, over an order of a magnitude higher than samples taken in March(3). This has been ascribed to the cleaning of ships in spring and points up the large seasonal variability in organotin levels. Fluvial, intertidal, and marine levels of dibutyltin at other sites in the Sado Estuary were 7.5-85, 5.0-57, and 10-50 ng/g, respectively.

In a survey of Canadian wines from 3 provinces, dibutyltin was the predominant butyltin present, with 23.2% of samples tested containing 1.1-138.1 ng/ml. The source of butyltin was not reported(1).

The only monitoring data located were for dibutyltin (Bu2Sn++) without regard for the identity of the accompanying anion(s) and concn was reported in Sn equivalents(1). Dibutyltin was detected and quantified in 1 of 14 samples of whole fish collected from Canadian surface waters during 1982 and 1984 at the following concn (species; location): 0.05 ppm Sn (wet wt), herring (C. harengus pallasi; Vancouver Harbor); dibutyltin also was detected, not quantified in another 4 of the samples (concn <0.01 ppm Sn (wet wt) (limit of quantitation))(1). The levels of dibutyltin in mussel tissue (n=14) in the Sado Estuary, Portugal were 5-82 ng/g dry wt(2).

POISONING CAUSED BY DIBUTYLTIN DILAURATE WAS DIAGNOSED IN CATTLE, MINK, & PALM DOVES (STREPTOPELIA SENEGALENSIS). ACCIDENTAL ADDITION OF DIBUTYLTIN DILAURATE PREMIX TO CALF-REARING CONCN AT LEVELS UP TO 25000 PPM ON 18 FARMS CAUSED POISONING IN 1000 CATTLE. HIGH CONCN OF TIN WERE FOUND IN CATTLE TISSUES & PRECLUDED THEIR CONSUMPTION BY HUMANS. PALM DOVES INGESTING CONCN CONTAINING 12500 PPM ON ONE FARM ALSO HAD HIGH CONCN OF TIN IN TISSUES. MINK APPEARED THE MOST SUSCEPTIBLE OF THE 3 SPECIES TO THIS COMPOUND.

NIOSH (NOES Survey 1981-1983) has statistically estimated that 89,107 are potentially exposed to dibutyltin dilaurate in the USA(1). Occupational exposure to dibutyltin dilaurate may occur through dermal contact with this compound at workplaces where dibutyltin dilaurate is produced or used(SRC). Monitoring data indicate that the general population may be exposed to dibutyltin via ingestion of food and drinking water, but this may or may not be due to the dilaurate(SRC).

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.

UN 3146; Organotin cmpd, solid, not otherwise specified

UN 2788; Organotin cmpd, liquid, not otherwise specified

IMO 6.1; Organotin cmpd, liquid or solid, not otherwise specified

Do not transport with food and feedstuffs.

UN Hazard Class: 6.1; UN Pack Group: III