Methylparaben

  • Methyl 4-hydroxybenzoate
  • Methyl p-hydroxybenzoate
  • 4-Hydroxybenzoic acid methyl ester
  • Methyl Butex
  • Preserval
  • Maseptol
Formula
4-(OH)C6H4(COOCH3)
Structure
Description
Solid.
Uses
Inhibitor of growth of molds & to lesser extent bacteria, as vehicle for ophthalmic soln., preservative.

Registry Numbers and Inventories.
CAS
99-76-3
EC (EINECS/ELINCS)
202-785-7
R 36/37/38
RTECS
DH2450000
RTECS class
Drug; Mutagen
UN (DOT)
2769
Merck
12,6182
Beilstein/Gmelin
509801
Beilstein Reference
4-10-00-00360
EPA OPP
61201
Swiss Giftliste 1
G-2363
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C8H8O3
Formula mass
152.15
Melting point, °C
125 - 128
Boiling point, °C
270 - 280
Density
1.1208 g/cm3 (137 C)
Solubility in water
Slightly soluble
Refractive index
1.5204 (137 C)
pKa/pKb
8.30 (pKa)
Partition coefficient, pKow
1.96
Heat of fusion
25.6 kJ/mol
Heat of vaporization
77.10 kJ/mol
Heat of combustion
-3751 kJ/mol

Hazards and Protection.
Storage
Store in a cool, dry, well-ventilated area away from incompatible substances. Keep containers tightly closed.
Handling
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Minimize dust generation and accumulation. Avoid contact with skin and eyes. Keep container tightly closed. Avoid ingestion and inhalation.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Avoid runoff into storm sewers and ditches which lead to waterways. Clean up spills immediately, using the appropriate protective equipment. Wear a self contained breathing apparatus and appropriate Personal protection. (See Exposure Controls, Personal Protection section). Sweep up, then place into a suitable container for disposal. Avoid generating dusty conditions. Provide ventilation.
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Strong oxidizing agents, strong bases.
Decomposition
Carbon monoxide, carbon dioxide, acrid smoke and fumes.

Fire.
Autoignition, °C
> 600
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Dusts at sufficient concentrations can form explosive mixtures with air. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. Extinguishing media: Use water spray, dry chemical, or carbon dioxide.
Hazards
Dusts at sufficient concentrations can form explosive mixtures with air.
Health
2
 
Flammability
0
 
 
Reactivity
0
 

Health.
Poison_Class
5
Exposure effects
Repeated exposure may cause sensitization dermatitis.
   Ingestion
May cause irritation of the digestive tract.
   Inhalation
May cause respiratory tract irritation.
   Skin
May cause skin sensitization, an allergic reaction, which becomes evident upon re-exposure to this material.
   Eyes
May cause moderate eye irritation.

First aid
 
   Ingestion
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid if cough or other symptoms appear. DO NOT use mouth-to-mouth respiration.
   Skin
Get medical aid immediately. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
   Eyes
Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Transport.
UN number
2769
Response guide
HS Code
2918 29 30