These cause serious allergies and health effects in some people. They do not break down into simple substances that are used as fertilizer by plants. Currently, scientists are investigating the possibility that degradation products from certain detergents are causing deformity in the sex organs of fish and aquatic life in some wetlands. As if this weren't enough, the environmental fate of many of the chemicals we use is utterly unknown. EPA and the National Toxicology Program suspect that many dyes and pigments have long term adverse effects on people and perhaps on the environment.
Studies are underway.
And it may not be safe for the environment in the long run either. Then I got the material safety data sheets from the manufacturers. I found many of the inks contained up to 20 percent glycol ether solvents. Glycol ethers are highly toxic solvents that are absorbed through your skin, can penetrate several types of heavy chemical gloves without changing the glove's appearance, can cause reproductive problems in humans, and cause birth defects and atrophy of the testicles in experimental animals. You need the Material Safety Data Sheet for further information.