Also known as: Silicic acid (H4SiO4), tetraethyl ester, BRN 1422225, EINECS 201-083-8, Ethyl silicate,, Orthosilicic acid, tetraethyl ester (+7 more)
CAS 78-10-4
Tetraethyl orthosilicate (CAS 78-10-4) is a chemical substance with GHS signal word Warning; key hazard signal: H226; H332; H335; H319. Key regulatory status: REACH registered, cosmetic ingredient cross-reference; source data from ECHA CLP, EPA ToxValDB, EPA CPDat, ECHA REACH, ILO ICSC, OSHA.
CAS, identifiers, formula, and alternate names for the matched substance record.
EU harmonized hazard classification, hazard statements, pictograms, and signal word.
| Hazard Class | H-Statements | Pictograms | Signal |
|---|---|---|---|
| Flam. Liq. 3; Acute Tox. 4 *; STOT SE 3; Eye Irrit. 2 | H226; H332; H335; H319 | GHS02; GHS07 | Warning |
International Chemical Safety Card hazard and exposure summary.
| Field | Value |
|---|---|
| Short-term Effects | The substance is irritating to the eyes, skin and respiratory tract. Exposure could cause lowering of consciousness. |
| Long-term Effects | The substance defats the skin, which may cause dryness or cracking. The substance may have effects on the kidneys. |
| Routes of Exposure | The substance can be absorbed into the body by inhalation of its vapour and by ingestion. |
Occupational exposure limits from OSHA, NIOSH, and ACGIH rows.
| Agency | Metric | Value | ppm | mg/m3 | Skin |
|---|---|---|---|---|---|
| OSHA | TWA | 100 ppm (850 mg/m³) | 100 | 850 | N |
| NIOSH | TWA | 10 ppm (85 mg/m³) | 10 | 85 | N |
| ACGIH | TWA | 10 ppm (85 mg/m³) | 10 | 85 | N |
| AIHA | ERPG-1 | 25 ppm | 25 | - | - |
| AIHA | ERPG-2 | 100 ppm | 100 | - | - |
| AIHA | ERPG-3 | 300 ppm | 300 | - | - |
Industrial and product-use categories associated with this substance.
Toxicology endpoints rendered from public NOAEL study rows.
| Value | Unit | Endpoint | Route | Species | Source |
|---|---|---|---|---|---|
| =44 | mg/m3 | DNEL local | inhalation | Human | ToxValDB GESTIS DNEL |
| 42064KRE49 | UNII | FDA UNII substance identifier | - | - | openFDA substances |
| >5.03 | mg/L | LC50 | Inhalation | - | NTP ICE acute inhalation |
| 10 | mg/L | LC50 | Inhalation | - | NTP ICE acute inhalation |
| >16.8 | mg/L | LC50 | Inhalation | - | NTP ICE acute inhalation |
| >2500 | mg/kg bw | LD50 | oral | Rat | NTP ICE acute oral |
| =6270 | mg/kg bw | LD50 | oral | Rat | NTP ICE acute oral |
| =0.2 | mg/m3 | LEL | inhalation | Rat | ECHA |
| =1500 | mg/m3 | LEL | inhalation | Rat | ECHA |
| =1704 | mg/m3 | LEL | inhalation | Mouse | ECHA |
| =2130 | mg/m3 | LEL | inhalation | Human | ToxValDB NIOSH IDLH |
| =3200 | mg/m3 | LEL | inhalation | Rat | ECHA |
| =1.022e+4 | mg/m3 | LEL | inhalation | Human | ToxValDB NIOSH IDLH |
| =2.000e+4 | mg/m3 | LEL | inhalation | Mouse | ECHA |
| =1.108e+5 | mg/m3 | LEL | inhalation | Human | ToxValDB DOE Protective Action Criteria |
| =51.84 | mg/kg bw/day | LOEL | oral | Rat | ToxValDB ECOTOX |
| <426 | mg/m3 | NOAEC | inhalation | Mouse | ECHA |
| =10 | mg/kg bw/day | NOAEL | oral | Rat | ECHA |
| =50 | mg/kg bw/day | NOAEL | oral | Rat | ECHA |
| >=100 | mg/kg bw/day | NOAEL | oral | Rat | ECHA |
| =426 | mg/m3 | NOAEL | inhalation | Mouse | ToxValDB EU SCOEL |
Showing 21 of 21 studies
Registration status from the ECHA REACH registered substances database.
| Status | Name | EC Number | Link |
|---|---|---|---|
| Registered | Tetraethyl orthosilicate | 201-083-8 | ECHA overview → |
Same-CAS cosmetic ingredient record for cross-vertical context.
Same-CAS pharmaceutical records from drug and bioactivity sources.
Same-CAS cannabis compliance and lab records where available.
1 cannabis record found in efsa substances.
View full cannabis profile →Tetraethyl orthosilicate (CAS 78-10-4) is classified under EU CLP Annex VI as Flam. Liq. 3; Acute Tox. 4 *; STOT SE 3; Eye Irrit. 2 with signal word Warning. Hazard statements: H226; H332; H335; H319. Source: EU CLP Annex VI (ECHA).
Tetraethyl orthosilicate has 21 NOAEL studies in the database. The lowest reported value is 44 mg/m3 via inhalation in Human. Source: ToxValDB GESTIS DNEL.
Occupational exposure limits for Tetraethyl orthosilicate are set by OSHA, NIOSH, ACGIH. 6 limit values from official agencies are documented in the database. Source: OSHA, NIOSH, ACGIH.
Yes, Tetraethyl orthosilicate is also indexed as a cosmetic ingredient under the name Tetraethyl Orthosilicate. View the full cosmetic safety profile on the ingredient page for detailed safety data, SCCS opinions, and regulatory status.
Safety data is sourced from ECHA CLP Annex VI, EPA ToxValDB, EPA CPDat, EPA DSSTox, ECHA REACH, ILO/WHO ICSC, OSHA/NIOSH/ACGIH, CosIng / Ingredients DB, ChEMBL / DailyMed, cannabis regulatory/lab databases. All data traces to primary regulatory sources and is updated from official government databases.
Tetraethyl orthosilicate also appears in cosmetics, pharmaceutical, cannabis databases.