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Pigment violet 29 is a perylene-based derivative that has a wide range of coloring applications, including paints, inks, paper, carpets, solar cells, and even drugs. Its more formal name is 3,4,9,10-perylenetetracarboxylic acid diimide.
The color of pigment violet 29 has been variously described as dark red-violet, bordeaux, black, maroon, and purple. In its solid form, its color depends on its particle size, its crystallinity, and, in some cases, the angle at which the viewer observes it.
In recent years, the US Environmental Protection Agency reviewed pigment violet 29 under the 2016 update of the Toxic Substances Control Act. In 2018, the EPA reported that the pigment “does not present an unreasonable risk of injury to human health or the environment under the conditions of use.” The ruling was based on the compound’s low solubility, vapor pressure, and bioaccumulation potential; and, among other factors, its poor absorption across all routes of exposure.
These findings are disputed by Rep. Frank Pallone (D-NJ), who recently became chair of the House Committee on Energy and Commerce. Pallone contends that the EPA did not consider the environmental hazards of the pigment’s uses by individual companies, and he intends to hold hearings on this and other agency rulings.
Pigment violet 29 hazard information
GHS classification*: skin corrosion/irritation, category 2 | |
H315—Causes skin irritation | ![]() |
GHS classification: serious eye damage/eye irritation, category 2A | |
H319—Causes serious eye irritation | ![]() |
GHS classification: specific target organ toxicity, single exposure, respiratory tract irritation, category 3 | |
H335—May cause respiratory irritation | ![]() |
*Globally Harmonized System of Classification and Labeling of Chemicals. Explanation of pictograms.
Pigment violet 29 fast facts
CAS Reg. No. | 81-33-4 |
Empirical formula | C24H10N2O4 |
Molar mass | 390.35 g/mol |
Appearance | Maroon to purple solid |
Melting point | >300 ºC |
Water solubility | Insoluble |
MOTW update: November 16, 2020
Pigment violet (PV29) is a perylene-based compound that is used in a wide range of coloring applications, including paints, inks, paper, carpets, solar cells, and drugs. In 2018, the US Environmental Protection Agency reported that it was a low risk to human health and the environment, but this was disputed by a scientific advisory committee and environmental groups. In the past month, EPA revised its assessment, stating that PV29 exposure poses unreasonable risks to workers under certain conditions. The agency ordered manufacturer Sun Chemical and importer BASF to provide additional data concerning worker exposure.

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