Tetraethoxysilane

H226: Flammable liquid and vapor [Warning Flammable liquids]

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

H332: Harmful if inhaled [Warning Acute toxicity, inhalation]

H335: May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

P210, P233, P240, P241, P242, P243, P261, P264+P265, P271, P280, P303+P361+P353, P304+P340, P305+P351+P338, P317, P319, P337+P317, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

This chemical does not meet GHS hazard criteria for < 0.1% (1 of 1197) of reports.

H226 (> 99.9%): Flammable liquid and vapor [Warning Flammable liquids]

H319 (> 99.9%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H332 (> 99.9%): Harmful if inhaled [Warning Acute toxicity, inhalation]

H335 (94%): May cause respiratory irritation [Warning Specific target organ toxicity, single exposure; Respiratory tract irritation]

Aggregated GHS information provided per 1197 reports by companies from 37 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 1 of 1197 reports by companies.

There are 36 notifications provided by 1196 of 1197 reports by companies with hazard statement code(s).

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website.

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

H336: May cause drowsiness or dizziness [Warning Specific target organ toxicity, single exposure; Narcotic effects]

H370: Causes damage to organs [Danger Specific target organ toxicity, single exposure]

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

H373: May causes damage to organs through prolonged or repeated exposure [Warning Specific target organ toxicity, repeated exposure]

P210, P233, P240, P241, P242, P243, P260, P261, P264, P264+P265, P270, P271, P280, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P308+P316, P319, P321, P332+P317, P337+P317, P362+P364, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

H320: Causes eye irritation [Warning Serious eye damage/eye irritation]

Fresh air, rest.

Remove contaminated clothes. 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.

Excerpt from NIOSH Pocket Guide for Ethyl silicate:

Eye: IRRIGATE IMMEDIATELY - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: SOAP WASH PROMPTLY - If this chemical contacts the skin, promptly wash the contaminated skin with soap and water. If this chemical penetrates the clothing, promptly remove the clothing and wash the skin with soap and water. Get medical attention promptly.

Breathing: RESPIRATORY SUPPORT - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible.

Swallow: MEDICAL ATTENTION IMMEDIATELY - If this chemical has been swallowed, get medical attention immediately. (NIOSH, 2024)

General First Aid:

· Call 911 or emergency medical service.

· Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination.

· Move victim to fresh air if it can be done safely.

· Administer oxygen if breathing is difficult.

· If victim is not breathing:

-- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance.

-- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).

-- If no pulse detected or no respiratory medical device available, provide continuous compressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.

· Remove and isolate contaminated clothing and shoes.

· For minor skin contact, avoid spreading material on unaffected skin.

· In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.

· For severe burns, immediate medical attention is required.

· Effects of exposure (inhalation, ingestion, or skin contact) to substance may be delayed.

· Keep victim calm and warm.

· Keep victim under observation.

· For further assistance, contact your local Poison Control Center.

· Note: Basic Life Support (BLS) and Advanced Life Support (ALS) should be done by trained professionals.

Specific First Aid:

· Wash skin with soap and water.

· In case of burns, immediately cool affected skin for as long as possible with cold water. Do not remove clothing if adhering to skin.

In Canada, an Emergency Response Assistance Plan (ERAP) may be required for this product. Please consult the shipping paper and/or the "ERAP" section.

(General first aid procedures)

Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: Soap wash promptly - If this chemical contacts the skin, promptly wash the contaminated skin with soap and water. If this chemical penetrates the clothing, promptly remove the clothing and wash the skin with soap and water. Get medical attention promptly.

Breathing: Respiratory support

Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately.

Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient.

SMALL FIRE: Dry chemical, CO2, water spray or alcohol-resistant foam. Do not use dry chemical extinguishers to control fires involving nitromethane (UN1261) or nitroethane (UN2842).

LARGE FIRE: Water spray, fog or alcohol-resistant foam. Avoid aiming straight or solid streams directly onto the product. If it can be done safely, move undamaged containers away from the area around the fire.

FIRE INVOLVING TANKS, RAIL TANK CARS OR HIGHWAY TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks in direct contact with flames. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2024)

Use water spray, foam, alcohol-resistant foam. In case of fire: keep drums, etc., cool by spraying with water.

Water, foam, dry chemical, carbon dioxide

This chemical is a flammable liquid. Poisonous gases including carbon monoxide and silicon oxide are produced in fire. Use dry chemical, carbon dioxide, or foam extinguishers. Vapors are heavier than air and will collect in low areas. Vapors may travel long distances to ignition sources and flashback. Vapors in confined areas may explode when exposed to fire. Containers may explode in fire. Storage containers and parts of containers may rocket great distances, in many directions. If material or contaminated runoff enters waterways, notify downstream users of potentially contaminated waters. Notify local health and fire officials and pollution control agencies. From a secure, explosion-proof location, use water spray to cool exposed containers. If cooling streams are ineffective (venting sound increases in volume and pitch, tank discolors or shows any signs of deforming), withdraw immediately to a secure position ...

· CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.

· Keep unauthorized personnel away.

· Stay upwind, uphill and/or upstream.

· Ventilate closed spaces before entering, but only if properly trained and equipped.

· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area.

· All equipment used when handling the product must be grounded.

· Do not touch or walk through spilled material.

· Stop leak if you can do it without risk.

· Prevent entry into waterways, sewers, basements or confined areas.

· A vapor-suppressing foam may be used to reduce vapors.

· Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers.

· Use clean, non-sparking tools to collect absorbed material.

Large Spill

· Dike far ahead of liquid spill for later disposal.

· Water spray may reduce vapor, but may not prevent ignition in closed spaces.

Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:

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

LARGE SPILL: Consider initial downwind evacuation for at least 300 meters (1000 feet).

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)

Immediate precautionary measure

· Isolate spill or leak area for at least 50 meters (150 feet) in all directions.

· Consider initial downwind evacuation for at least 300 meters (1000 feet).

· 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.

Personal protection: complete protective clothing including self-contained breathing apparatus. Ventilation. Remove all ignition sources. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations. Note: Reacts with water to form an adhesive mass.

SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.

Remove all ignition sources. Ventilate area of spill or leak. For small quantities, absorb on paper towels. Evaporate in safe place (such as a fume hood). Allow sufficient time for evaporating vapors to completely clear hood ductwork. Burn paper in suitable location away from combustible materials ... Ethyl silicate should not be allowed to enter a confined space, such as a sewer, because of the possibility of an explosion. Sewers designed to preclude formation of explosive concn of ethyl silicate vapors are permitted.

Collect leaking liquid in sealable containers. Absorb remaining liquid in sand or inert absorbent and remove to safe place. Note: Reacts with water to form an adhesive mass.

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

Incineration in admixture with a more flammable solvent. /SRP: Process eqipped with afterburner and effluent gas scrubber./

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.

SRP: Local exhaust ventilation should be applied wherever there is an incidence of point source emissions or dispersion of regulated contaminants in the work area. Ventilation control of the contaminant as close to its point of generation is both the most economical and safest method to minimize personnel exposure to airborne contaminants.

Precautions should be taken in industrial handling to avoid repeated or prolonged contact with higher concn of the vapor and to avoid contact of the vapor or liquid with the eyes.

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.

For more Preventive Measures (Complete) data for Ethyl silicate (7 total), please visit the HSDB record page.

Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. All equipment used when handling the product must be grounded. Do not touch or walk through spilled material. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. A vapor-suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean, non-sparking tools to collect absorbed material.

LARGE SPILL: Dike far ahead of liquid spill for later disposal. Water spray may reduce vapor, but may not prevent ignition in closed spaces. (ERG, 2024)

Fireproof. Separated from acids and oxidants. Cool. Dry. Keep in a well-ventilated room.

Ethyl silicate must be stored to avoid contact with strong oxidizers (such as chlorine, bromine, and fluorine) since violent reactions occur. Before entering confined space where this chemical may be present, check to make sure that an explosive concentration does not exist. Store in tightly closed containers in a cool, well-ventilated area away from water. Sources of ignition, such as smoking and open flames, are prohibited where ethyl silicate is handled, used, or stored. Metal containers involving the transfer of five gallons or more of ethyl silicate should be grounded and bonded. Drums must be equipped with self-closing valves, pressure vacuum bungs, and flame arresters. Use only non-sparking tools and equipment, especially when opening and closing containers of ethyl silicate.

· Wear positive pressure self-contained breathing apparatus (SCBA).

· Structural firefighters' protective clothing provides thermal protection but only limited chemical protection.

10.0 [ppm]

25 [ppm]

100 [ppm]

300 [ppm]

10 ppm (85 mg/m³)

TWA 10 ppm (85 mg/m3)

100.0 [ppm]

100 ppm (850 mg/m³)

TWA 100 ppm (850 mg/m3) See Appendix G

700 ppm (NIOSH, 2024)

700.0 [ppm]

Excerpts from Documentation for IDLHs: Human data: Exposure to a concentration of 1,200 ppm caused lacrimation and 250 ppm caused irritation of the eyes and nose [Smyth and Seaton 1940]. It has been stated that 700 ppm is probably intolerable for more than 30 minutes [Smyth and Seaton 1940].

See: 78104

8 hr Time Weighted Avg (TWA): 10 ppm.

Excursion Limit Recommendation: Excursions in worker exposure levels may exceed 3 times the TLV-TWA for no more than a total of 30 minutes during a work day, and under no circumstances should they exceed 5 times the TLV-TWA, provided that the TLV-TWA is not exceeded.

1 ppm as TWA.

CAUTION: The majority of these products have a very low flash point. Use of water spray when fighting fire may be inefficient.

Small Fire

· Dry chemical, CO2, water spray or alcohol-resistant foam.

· Do not use dry chemical extinguishers to control fires involving nitromethane (UN1261) or nitroethane (UN2842).

Large Fire

· Water spray, fog or alcohol-resistant foam.

· Avoid aiming straight or solid streams directly onto the product.

· If it can be done safely, move undamaged containers away from the area around the fire.

Fire Involving Tanks, Rail Tank Cars or Highway Tanks

· Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles.

· Cool containers with flooding quantities of water until well after fire is out.

· Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank.

· ALWAYS stay away from tanks in direct contact with flames.

· For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn.

ERPG-1: 25 ppm - one hour exposure limit: 1 = mild transient health effects or objectionable odor [AIHA]

ERPG-2: 100 ppm - one hour exposure limit: 2 = impaired ability to take protective action [AIHA]

ERPG-3: 300 ppm - one hour exposure limit: 3 = life threatening health effects [AIHA]

Emergency Response Planning Guidlines (ERPGs) for tetraethoxysilane: [Table#1531]

A harmful contamination of the air will be reached rather slowly on evaporation of this substance at 20 °C.

The substance is irritating to the eyes, skin and respiratory tract. Exposure could cause lowering of consciousness.

The substance defats the skin, which may cause dryness or cracking. The substance may have effects on the kidneys.

Excerpt from NIOSH Pocket Guide for Ethyl silicate:

Ethyl silicate appears as a clear colorless liquid with a faint odor. Flash point 125 °F. Less dense than water. Vapors are heavier than air.

Other Solid; CBI; Liquid; Liquid; Other Solid

Colorless liquid with a sharp, alcohol-like odor; [NIOSH]

COLOURLESS LIQUID WITH CHARACTERISTIC ODOUR.

Colorless liquid with a sharp, alcohol-like odor.

Colorless liquid

Water-white

SHARP, ESTER-LIKE ODOR

Faint odor

Sharp alcohol-like odor

336 °F at 760 mmHg (USCG, 1999)

168.8 °C

168.8 °C @760 [mm Hg]

-121.9 °F (USCG, 1999)

-82.5 °C

99 °F (USCG, 1999)

125 °F (52 °C) (Open cup)

99 °F (Closed cup)

37 °CC, closed-cup

37 °C c.c.

Reacts with water (NIOSH, 2024)

Soluble in ether

Slightly soluble in benzene

Miscible with alcohol

Decomposes in water

Solubility in water: slowly hydrolyzes

0.933 at 68 °F (USCG, 1999) - Less dense than water; will float

0.933 at 20 °C

Bulk density: 7.8 lbs/gal at 20 °C

Relative density (water = 1): 0.93

0.9320 @ 20°C

7.22 (Air = 1)

Relative vapor density (air = 1): 7.22

1 mmHg (NIOSH, 2024)

1.88 [mmHg]

VP: 1.0 MM HG AT 20 °C

1.88 mm Hg at 25 °C

Vapor pressure, Pa at 20 °C: 200

7.5 [mm Hg] @21.6 °C

When heated to decomposition it emits acrid smoke and fumes.

Flammable. Practically insoluble in water. Reacts slowly with water to form silica and ethyl alcohol [Merck].

Siloxanes

Highly Flammable

ETHYL SILICATE reacts exothermically with acids Strong oxidizing acids may cause a reaction that is sufficiently exothermic to ignite the reaction products. May generate with caustic solutions. May generate flammable hydrogen with alkali metals and hydrides.

Strong oxidizers, water [Note: Reacts with water to form a silicone adhesive (a milky-white mass)].

Causes swelling and hardening of some plastics.

Strong oxidizers, water [Note: Reacts with water to form a silicone adhesive (a milky-white mass).]

The substance can be absorbed into the body by inhalation of its vapour and by ingestion.

inhalation, ingestion, skin and/or eye contact

Cough. Dizziness. Headache. Sore throat.

Dry skin. Redness.

Redness. Pain.

Confusion. Vomiting. Further see Inhalation.

irritation eyes, nose; In Animals: lacrimation (discharge of tears); dyspnea (breathing difficulty), pulmonary edema; tremor, narcosis; liver, kidney damage; anemia

Eyes, respiratory system, liver, kidneys, blood, skin

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.

Nephrotoxin - The chemical is potentially toxic to the kidneys in the occupational setting.

LCLo (rat) = 1,000 ppm/4H

LD50 Rat oral 6270 mg/kg

LD50 Rabbit skin 5878 mg/kg

Three experiments were conducted to determine the effects of excess dietary calcium carbonate, phosphorus and urine acidifying and alkalizing salts on silica urolith formation in a model using rats fed dextrose-based diets containing 2% tetraethylorthosilicate (TES). Diets containing 2% TES lowered wt gains to 91-95% of gains made by rats fed non-TES diets. Urine silica concn of rats fed TES were generally in the range of 50-60 mg/dL. In expt 1, rats fed TES with no additional dietary calcium carbonate had a silica urolith incidence of 35%. With additions of 1 and 2% calcium carbonate to the basal-TES diet, respective urolith incidences were 45 and 60% (r = 0.99, P < 0.02). In expt 2, monobasic sodium phosphate (MP) providing 0.2% additional phosphorus resulted in a mean urine pH of 6.42 and no uroliths. Dibasic sodium phosphate (DP) without and with 0.5% sodium bicarbonate (SB) resulted in respective urine pH values of 6.78 and 7.14 and urolith incidences of 15 and 20% (MP less than DP and DP + SB, P < 0.05). However, the uroliths were small averaging less than 1 mg. In expt 3, substitution of autoclaved egg albumin for casein, the protein source in expt 1 and 2, resulted in urine pH of 7.45 and a silica urolith incidence of 46%. An equal-molar mixture of MP and DP providing an added 0.2% phosphorus resulted in a urine pH of 7.07 and reduced the urolith incidence to 4%, and 0.75% of dietary ammonium chloride either with or without the added 0.2% phosphorus gave urine acidification and complete protection from uroliths ...

Rats fed a dextrose-casein type of diet adequate for normal growth and containing 2% of tetraethylorthosilicate were used to study the effect of sodium chloride and sodium sulfate drinking waters & dietary additions of chloride, sulfate & phosphate on formation of silica urinary calculi. 50% of rats fed the basal-tetraethylorthosilicate diet (2%) developed silica urinary calculi. Addition of 0.2 eq/kg diet of chloride, sulfate or phosphate as sodium salts (phosphate was an equal molar mixture of mono- and dibasic sodium phosphates) resulted in a reduction in silica urinary calculi (P <0.05) by dietary chloride (15% incidence) and phosphate (5% incidence) but not by sulfate (35% incidence).

Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Silane, Chlorosilane, and Related Compounds/

Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Anticipate seizures and treat if necessary ... . Monitor for shock and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 ml/kg up to 200 ml of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal (refer to ingestion protocol in Section Three ... . Cover skin burns with sterile dressings after decontamination ... . /Silane, Chlorosilane, and Related Compounds/

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Early intubation at the first sign of upper airway obstruction may be necessary. Positive-pressure ventilation techniques with a bag-valve-mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's (LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors if patient is hypotensive with a normal fluid volume. Watch for signs of fluid overload ... . Treat seizures with diazepam or lorazepam ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Silane, Chlorosilane, and related compounds/

The following medical procedures should be made available to each employee who is exposed to ethyl silicate at potentially hazardous levels: Employees should be screened for history of certain medical conditions which might place the employees at increased risk from ethyl silicate exposure. /These are/ chronic respiratory disease ... liver disease ... kidney disease ... blood disease ... skin disease. ... Any employee developing the above-listed conditions should be referred for further medical examination.

/HUMAN EXPOSURE STUDIES/ ... Human experiments found: 3000 ppm is extremely irritating to the eyes and nose; 1200 ppm stings eyes and nose and produces tears; 700 ppm mildly stings eyes and nose; 250 ppm makes the eyes and nose tingle slightly; 85 ppm can be detected only by odor. It appeared that 700 ppm would be intolerable to human beings for more than half an hour.

/SIGNS AND SYMPTOMS/ Skin or eye contact can cause severe irritation or burns. The vapor can irritate the nose, eyes, throat, and bronchial tubes, causing cough and difficulty breathing. Higher exposures can cause pulmonary edema, a medical emergency that can be delayed for several hours. This can cause death. Repeated skin contact can cause dryness and cracking.

/SIGNS AND SYMPTOMS/ Orally, the ethyl silicate is moderately toxic, but may be /CNS depressant/ in high concentrations.

/SIGNS AND SYMPTOMS/ Potential symptoms of overexposure are irritation of eyes and nose.

For more Human Toxicity Excerpts (Complete) data for Ethyl silicate (6 total), please visit the HSDB record page.

/LABORATORY ANIMALS: Acute Exposure/ Acute stomach, kidney, and bladder toxicity was evaluated in F344 rats after gastric gavage of tetraethylorthosilicate (TES) at daily doses of 0, 0.111, 0.223, and 0.333 g. Five rats of each sex at each dose were sacrificed after 1, 2, and 4 days. In TES-treated groups, silicate accumulated in the stomach glands and the muscle layer of the forestomach and glandular stomach. Serum chemistries demonstrated acute onset of renal failure. In the kidneys, acute tubular necrosis, accumulation of silicates, and superficial necrotizing papillitis were observed. In the renal pelvis and bladder, there was urothelial simple hyperplasia, focal erosion of the mucosa, edema, and inflammation. These acute toxic changes were dose and time dependent, but significant sex differences were not observed. The microscopic changes in the urothelium were similar to those observed following administration of high doses of sodium saccharin to male rats in which urinary silicate precipitate and crystals form.

/LABORATORY ANIMALS: Acute Exposure/ The toxicities of silicon tetraalkoxides, including tetramethoxysilane [Si(OCH3)4, TMOS], tetraethoxysilane [Si(OC2H5)4, TEOS], tetrapropoxysilane [Si(OC3H7)4, TPOS] and tetrabuthoxysilane [Si(OC4H9)4, TBOS], were investigated with ip injection of 1,000 mg/kg of each compound. TMOS, as well as TEOS, caused acute tubular necrosis. Blood biochem exam revealed elevation of blood urea nitrogen and creatinine in mice treated with TEOS, TPOS and TBOS, though TMOS treated mice died and therefore could not be examined. The severity of nephrotoxicity differs among these silicon tetraalkoxides. The spleens of mice treated with TMOS exhibited cytolysis in the white and red pulp, suggesting direct injury to the spleen. The kidney seems to be a common target organ of silicon tetraalkoxides.

/LABORATORY ANIMALS: Acute Exposure/ To clarify the time course of toxicological effects of tetraethoxysaline [Si(OC2H5)4, TEOS] on the kidney and the relationship between blood silicon levels (Si-B) and the effects, 250 mg/kg or 500 mg/kg TEOS was ip administered to ten 5-wk-old male ICR mice (SPF grade) in each group, and morphological and functional changes of the kidney were assessed at 12 hr, 24 hr, 3 days and 2 wk after administration of TEOS. Injury to tubular epithelial cells was observed in mice killed 12 and 24 hr after administration, and its severity increased with increasing dosage. The mean values of blood urea nitrogen exhibited dose-related increase in mice sacrificed 24 hr after the administration. The concentrations of Si-B increased in order of the administered doses of TEOS, and then decreased steadily. The results of Si-B were consistent with the concept that renal toxicity of TEOS is mediated by siliceous compounds. The kidney was recovering from injury 3 days after administration, and had developed tubulointerstitial nephritis, which could be regarded as repaired lesion of acute injury, by 2 wk after administration.

/LABORATORY ANIMALS: Acute Exposure/ To clarify the acute inhalation toxicity of tetraethoxysilane [TEOS, Si(OC2H5)4], groups of ten male ICR mice (SPF grade) were exposed to 1000 ppm TEOS for 1, 2, 4, or 8 hr. The numbers of mice that died during 2 wk of observation were 0, 1, 1 and 6 in the 1, 2, 4, and 8 hr inhalation experiments. In the acute inhalation study, bw decreased after TEOS exposure and did not reach the level of control mice during 2 wk of observation except in the 1-hr inhalation study. Acute tubular necrosis (ATN) and acute splenic atrophy (ASA) were observed in all dead mice in the acute inhalation study, and tubulointerstitial nephritis (TIN) was frequently found in the surviving mice ... However, blood biochemical examinations revealed no evidence of renal dysfunction. The olfactory epithelium was necrotic in all dead mice ... The LCL0 /Lethal concentration lo/ for 1 hr exposure to TEOS and LC50 for 4 hr exposure are greater than 1000 ppm, and ... the kidney and nasal mucosa are the target organs for TEOS inhalation.

For more Non-Human Toxicity Excerpts (Complete) data for Ethyl silicate (17 total), please visit the HSDB record page.

In persons with impaired pulmonary function, especially those with obstructive airway diseases, the breathing of ethyl silicate might cause exacerbation of symptoms due to its irritant properties. ... Persons with pre-existing blood disorders may be more susceptible to the effects of this agent. ... Persons with pre-existing skin disorders may be more susceptible to the effects of this agent.

Tetraethyl silicate's production and use in the sol-gel, casting and glass frosting processes may result in its release to the environment through various waste streams; its use as a weatherproofing and protective coating agent may result in its direct release to the environment. If released to air, a vapor pressure of 1.88 mm Hg at 25 °C indicates tetraethyl silicate will exist solely in the vapor phase in the atmosphere. Vapor-phase tetraethyl silicate will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 16 hours. Tetraethyl silicate does not contain chromophores that absorb at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunlight. If released to soil, tetraethyl silicate is expected to have very high mobility based upon an estimated Koc of 1. Volatilization from moist soil surfaces may be an important fate process based upon an estimated Henry's Law constant of 2.0X10-5 atm-cu m/mole. Tetraethyl silicate may volatilize from dry soil surfaces based upon its vapor pressure. Biodegradation data were not available. If released into water, tetraethyl silicate is not expected to adsorb to suspended solids and sediment based upon the estimated Koc. Volatilization from water surfaces may be an important fate process based upon this compound's estimated Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 2.9 and 25 days respectively. An estimated BCF of 3 suggests bioconcentration in aquatic organisms is low. Tetraethyl silicate is expected to undergo hydrolysis in aqueous environmental conditions, or on contact with water; without special precautions, tetraethoxysilane hydrolyzes to a gel in about 10 days. Occupational exposure to tetraethyl silicate may occur through inhalation and dermal contact with this compound at workplaces where it is produced or used. It is unlikely that the general population would be exposed to tetraethyl silicate as it is primarily used in weatherproofing mortar and cements or in a manufacturing or research setting, and it hydrolyzes upon contact with water. (SRC)

Tetraethyl silicate's production and use as a chemical sol-gel(1,2), and in casting(3) and glass frosting(1) processes may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that tetraethyl silicate is expected have very high mobility in soil(SRC). Volatilization of tetraethyl silicate from moist soil surfaces may be an important fate process(SRC) given an estimated Henry's Law constant of 2.0X10-5 atm-cu m/mole(SRC), using a fragment constant estimation method(3). Tetraethyl silicate is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 1.88 mm Hg at 25 °C(4). Biodegradation data were not available(SRC, 2009). Without special precautions, tetraethoxysilane hydrolyzes to a gel in about 10 days(5).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that tetraethyl silicate is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces may occur(3) based upon an estimated Henry's Law constant of 2.0X10-5 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 2.9 and 25 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 3(SRC), from an estimated log Kow of 0.04(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Biodegradation data were not available(SRC, 2009). Without special precautions, tetraethoxysilane hydrolyzes to a gel in about 10 days(8).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), tetraethyl silicate, which has a vapor pressure of 1.88 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase tetraethyl silicate 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 16 hours(SRC), calculated from its rate constant of 2.5X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Tetraethyl silicate does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

The rate constant for the vapor-phase reaction of tetraethyl silicate with photochemically-produced hydroxyl radicals has been estimated as 2.5X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 16 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Tetraethyl silicate is expected to undergo hydrolysis in the environment similar to most alkoxysilanes(2). Tetraethyl silicate is reported to hydrolyze in aqueous conditions(3). Tetraethyl silicate does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

An estimated BCF of 3 was calculated for ethyl silicate(SRC), using an estimated log Kow of 0.04(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of tetraethyl silicate can be estimated to be 1(SRC). According to a classification scheme(2), this estimated Koc value suggests that tetraethyl silicate is expected to have very high mobility in soil.

The Henry's Law constant for tetraethyl silicate is estimated as 2.0X10-5 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that tetraethyl silicate may volatilize from water surfaces(2). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(2) is estimated as 2.9 days(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(2) is estimated as 25 days(SRC). Henry's Law constant of tetraethyl silicate indicates that volatilization from moist soil surfaces may occur(SRC). Tetraethyl silicate may volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 1.88 mm Hg(3).

Tetraethyl silicate's production and use in the sol-gel, casting and glass frosting processes may result in its release to the environment through various waste streams; its use as a weatherproofing and protective coating agent may result in its direct release to the environment. If released to air, a vapor pressure of 1.88 mm Hg at 25 °C indicates tetraethyl silicate will exist solely in the vapor phase in the atmosphere. Vapor-phase tetraethyl silicate will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 16 hours. Tetraethyl silicate does not contain chromophores that absorb at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunlight. If released to soil, tetraethyl silicate is expected to have very high mobility based upon an estimated Koc of 1. Volatilization from moist soil surfaces may be an important fate process based upon an estimated Henry's Law constant of 2.0X10-5 atm-cu m/mole. Tetraethyl silicate may volatilize from dry soil surfaces based upon its vapor pressure. Biodegradation data were not available. If released into water, tetraethyl silicate is not expected to adsorb to suspended solids and sediment based upon the estimated Koc. Volatilization from water surfaces may be an important fate process based upon this compound's estimated Henry's Law constant. Estimated volatilization half-lives for a model river and model lake are 2.9 and 25 days respectively. An estimated BCF of 3 suggests bioconcentration in aquatic organisms is low. Tetraethyl silicate is expected to undergo hydrolysis in aqueous environmental conditions, or on contact with water; without special precautions, tetraethoxysilane hydrolyzes to a gel in about 10 days. Occupational exposure to tetraethyl silicate may occur through inhalation and dermal contact with this compound at workplaces where it is produced or used. It is unlikely that the general population would be exposed to tetraethyl silicate as it is primarily used in weatherproofing mortar and cements or in a manufacturing or research setting, and it hydrolyzes upon contact with water. (SRC)

Tetraethyl silicate's production and use as a chemical sol-gel(1,2), and in casting(3) and glass frosting(1) processes may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that tetraethyl silicate is expected have very high mobility in soil(SRC). Volatilization of tetraethyl silicate from moist soil surfaces may be an important fate process(SRC) given an estimated Henry's Law constant of 2.0X10-5 atm-cu m/mole(SRC), using a fragment constant estimation method(3). Tetraethyl silicate is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 1.88 mm Hg at 25 °C(4). Biodegradation data were not available(SRC, 2009). Without special precautions, tetraethoxysilane hydrolyzes to a gel in about 10 days(5).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1(SRC), determined from a structure estimation method(2), indicates that tetraethyl silicate is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces may occur(3) based upon an estimated Henry's Law constant of 2.0X10-5 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 2.9 and 25 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 3(SRC), from an estimated log Kow of 0.04(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Biodegradation data were not available(SRC, 2009). Without special precautions, tetraethoxysilane hydrolyzes to a gel in about 10 days(8).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), tetraethyl silicate, which has a vapor pressure of 1.88 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase tetraethyl silicate 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 16 hours(SRC), calculated from its rate constant of 2.5X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Tetraethyl silicate does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

The rate constant for the vapor-phase reaction of tetraethyl silicate with photochemically-produced hydroxyl radicals has been estimated as 2.5X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 16 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Tetraethyl silicate is expected to undergo hydrolysis in the environment similar to most alkoxysilanes(2). Tetraethyl silicate is reported to hydrolyze in aqueous conditions(3). Tetraethyl silicate does not contain chromophores that absorb at wavelengths >290 nm(4) and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

An estimated BCF of 3 was calculated for ethyl silicate(SRC), using an estimated log Kow of 0.04(1) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of tetraethyl silicate can be estimated to be 1(SRC). According to a classification scheme(2), this estimated Koc value suggests that tetraethyl silicate is expected to have very high mobility in soil.

The Henry's Law constant for tetraethyl silicate is estimated as 2.0X10-5 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that tetraethyl silicate may volatilize from water surfaces(2). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(2) is estimated as 2.9 days(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(2) is estimated as 25 days(SRC). Henry's Law constant of tetraethyl silicate indicates that volatilization from moist soil surfaces may occur(SRC). Tetraethyl silicate may volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 1.88 mm Hg(3).

NIOSH (NOES Survey 1981-1983) has statistically estimated that 10,422 workers (2,566 of these were female) were potentially exposed to tetraethyl silicate in the US(1). Occupational exposure to tetraethyl silicate may occur through inhalation and dermal contact with this compound at workplaces where it is produced or used. It is unlikely that the general population would be exposed to tetraethyl silicate as it is primarily used in weatherproofing mortar and cements or in a manufacturing or research setting, and it hydrolyzes upon contact with water(SRC).

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in soil or water; effects on animal and plant life; and conformance with environmental and public health regulations.

Incineration in admixture with a more flammable solvent. /SRP: Process eqipped with afterburner and effluent gas scrubber./

/GUIDE 129: FLAMMABLE LIQUIDS (Polar/Water-Miscible/Noxious)/ Fire or Explosion: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers. Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. Runoff to sewer may create fire or explosion hazard. Containers may explode when heated. Many liquids are lighter than water.

/GUIDE 129: FLAMMABLE LIQUIDS (Polar/Water-Miscible/Noxious)/ Health: May cause toxic effects if inhaled or absorbed through skin. Inhalation or contact with material may irritate or burn skin and eyes. Fire will produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution.

/GUIDE 129: FLAMMABLE LIQUIDS (Polar/Water-Miscible/Noxious)/ Public Safety: CALL Emergency Response Telephone Number on Shipping Paper first. If Shipping Paper not available or no answer, refer to appropriate telephone number listed on the inside back cover. As an immediate precautionary measure, isolate spill or leak area for at least 50 meters (150 feet) in all directions. Keep unauthorized personnel away. Stay upwind. Keep out of low areas. Ventilate closed spaces before entering.

/GUIDE 129: FLAMMABLE LIQUIDS (Polar/Water-Miscible/Noxious)/ Protective Clothing: Wear positive pressure self-contained breathing apparatus (SCBA). Structural firefighters' protective clothing will only provide limited protection.

For more DOT Emergency Guidelines (Complete) data for Ethyl silicate (8 total), please visit the HSDB record page.

UN 1292; Tetraethyl silicate

IMO 3.3; Tetraethyl silicate

No person may /transport,/ offer or accept a hazardous material for transportation in commerce unless that person is registered in conformance ... and the hazardous material is properly classed, described, packaged, marked, labeled, and in condition for shipment as required or authorized by ... /the hazardous materials regulations (49 CFR 171-177)./

The International Air Transport Association (IATA) Dangerous Goods Regulations are published by the IATA Dangerous Goods Board pursuant to IATA Resolutions 618 and 619 and constitute a manual of industry carrier regulations to be followed by all IATA Member airlines when transporting hazardous materials.

The International Maritime Dangerous Goods Code lays down basic principles for transporting hazardous chemicals. Detailed recommendations for individual substances and a number of recommendations for good practice are included in the classes dealing with such substances. A general index of technical names has also been compiled. This index should always be consulted when attempting to locate the appropriate procedures to be used when shipping any substance or article.

Flammable Liquid

Symbol: Xn; R: 10-20-36/37; S: (2)

UN Hazard Class: 3; UN Pack Group: III