Phthalic Anhydride TSCA Risk Evaluation Consortium
What Is Phthalic Anhydride?
Phthalic anhydride (PA) is a key chemical building block in American manufacturing. It is primarily used as an intermediate in producing plasticizers, resins, and coatings. Through these applications, PA supports major industries such as automotive, construction, electronics, and consumer goods.
Why It Matters. Phthalic anhydride is critical to producing materials that support modern life:
- Plasticizers: PA is used to make high-volume plasticizers such as DINP, DIDP, and DPHP. These soften PVC for use in medical tubing, automotive interiors, flooring, roofing membranes, and wire insulation.
- Alkyd Resins: PA is a key ingredient in alkyd-based paints, varnishes, inks, and coatings that protect and enhance homes, industrial buildings, vehicles, and furniture.
- Unsaturated Polyester Resins (UPRs): Phthalic anhydride is used to make UPRs, which are then incorporated into fiberglass-reinforced plastics found in boats, bathroom fixtures, construction panels, and consumer goods.
- Other Uses: PA is also used in the manufacture of polyester polyols, pigments and dyes, herbicides, and specialty polymers such as polyetherimides.
FAQs
Phthalic anhydride is primarily used in the production of plasticizers, alkyd resins, and unsaturated polyester resins. These materials are essential to make products like PVC plastics, paints and coatings, fiberglass, automotive parts, electronics, and construction materials.
When handled responsibly, yes. Phthalic anhydride is regulated by the U.S. Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA). Manufacturers follow strict protocols to protect workers and limit environmental releases. While these measures focus on workplace and environmental safety, phthalic anhydride itself is typically consumed in manufacturing processes and not present in finished consumer products.
Yes. EPA is currently conducting a risk evaluation for phthalic anhydride under the Toxic Substances Control Act (TSCA). OSHA enforces workplace exposure limits, while the National Institute for Occupational Safety and Health (NIOSH) and the American Conference of Governmental Industrial Hygienists (ACGIH) provide additional safety guidelines.
Pthalic anhydride is produced by oxidizing either ortho-xylene or naphthalene in the presence of a catalyst. The result is a white crystalline solid that serves as a ‘building block’ chemical (an intermediate) for many other products.
You’ll find phthalic anhydride-based materials in flooring, wall coverings, car interiors, home appliances, paints and varnishes, marine coatings, and more. It’s a behind-the-scenes contributor to many modern conveniences in our homes, vehicles, and workplaces.
Phthalic Anhydride TSCA Risk Evaluation Consortium Members
The Phthalic Anhydride Consortium is comprised of leading companies committed to advancing safety and innovation in PA manufacturing and use.