On Sunday India heralds the arrival of spring with the festival of Holi. While Holi is a Hindu ritual, it is celebrated with bonfires and parties by Indians of all religions. But one aspect of Holi is prompting health concerns. VOA's Steve Herman reports from New Delhi.

The ancient Hindu festival of Holi, celebrating the triumph of good over bad, is certainly one of India's most colorful holidays. People paint each other's faces by hand, or spray dyes from a pump, with a cheer of:

"Bura na maano Holi hai!"

Loosely translated, the chant means, "Don't let this bother you, because today is Holi."

But some environmentalists, physicians and even the police are expressing concern over Holi. It turns out that the colors people splash on each other can be dangerous.

While the vivid mixtures were once derived solely from plants, the colors sold nowadays at roadside stalls are frequently industrial dyes.

At the Delhi Skin Clinic, dermatologist Vijendra Kaushik says he sees a surge in patients complaining of skin problems immediately after Holi.

"They can cause contact dermatitis, as well as irritant dermatitis," he said.  "Many times, some miscreants, they mix some acids or toxic things in that, so that can cause burns also."

Dangerous chemicals and metals found in Holi paints include chromium, nickel, and cadmium.  The red sometimes contains highly toxic mercuric sulfate.  And ophthalmologists warn revelers to keep an eye out for green, which frequently is made of copper sulfate, which is capable of causing puffiness and even temporary blindness.

Delhi dermatologist Kaushik says an ounce of prevention and patience can reduce the side effects of Holi.

"Before you play Holi you must apply liberal oil on your skin - plain coconut oil, good emollient, so that when you take a bath it will come off easily," he added.  "Do not use detergents or strong caustics to remove your colors. It may take two days, three days, four days, [but] it will come off."

The hazards have prompted officials and private organizations to launch campaigns warning of the dangers of chemical dyes, and promoting the use of safe ingredients.

Supporters of the all-natural Holi movement say they hope the effort will help the holiday return to its more holistic roots.