Reported in EPA TSCA Inventory.

The systematic name of Methyl nadic anhydride is (3aR,4S,7aS)-8-methyl-3a,4,7,7a-tetrahydro-4,7-methano-2-benzofuran-1,3-dione. With the CAS registry number 25134-21-8, it is also named as 4,7-Methanoisobenzofuran-1,3-dione, 3a,4,7,7a-tetrahydromethyl-. The product's categories are norbornene derivatives and organics. It is clear light yellow oily liquid which is sensitive to moisture. It can be used as epoxy resin curing agent.

The Methyl nadic anhydride is harmful if swallowed. It is irritating to eyes, respiratory system and skin. And it also can cause burns. In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. If you want to contact this product, you must wear suitable protective clothing, gloves and eye/face protection. In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.)

The other characteristics of this product can be summarized as: (1)ACD/LogP: 0.45; (2)# of Rule of 5 Violations: 0; (3)ACD/LogD (pH 5.5): 0.45; (4)ACD/LogD (pH 7.4): 0.45; (5)ACD/BCF (pH 5.5): 1.29; (6)ACD/BCF (pH 7.4): 1.29; (7)ACD/KOC (pH 5.5): 41.75; (8)#H bond acceptors: 3; (9)#H bond donors: 0; (10)Index of Refraction: 1.553; (11)Molar Refractivity: 43.78 cm³; (12)Molar Volume: 136.7 cm³; (13)Polarizability: 17.35×10^-24 cm³; (14)Surface Tension: 42.9 dyne/cm; (15)Enthalpy of Vaporization: 56.83 kJ/mol; (16)Boiling Point: 326.1 °C at 760 mmHg; (17)Vapour Pressure: 0.00022 mmHg at 25°C; (18)Exact Mass: 178.062994; (19)MonoIsotopic Mass: 178.062994; (20)Topological Polar Surface Area: 43.4; (21)Heavy Atom Count: 13.

People can use the following data to convert to the molecule structure. 
1.SMILES: O=C1OC(=O)[C@@H]3[C@H]1[C@H]2/C=C\[C@H]3[C@H]2C;
2.InChI: InChI=1/C10H10O3/c1-4-5-2-3-6(4)8-7(5)9(11)13-10(8)12/h2-8H,1H3/t4-,5-,6-,7+,8-/m0/s1; 
3.InChIKey: SBKPSHZVULRXED-ZXVYDBTHBA.

The following is the toxicity data which has been tested.