Behind the water pipelines near Mahim causeway, amid heaps of garbage and stagnant black sewage water, workers are busy preparing for Holi — crushing, drying and filtering colour powder. It is from this filthy place, nearly 1,000 kg of colour powder — red, yellow, blue, green, orange and purple — will make their way to several small shops and markets.

Small-time businessman Mohammed Hayat says he has been selling colours during Holi for the last 11 years. When Newsline visited the lanes behind the water mains, Hayat, his brother and a child labourer were busy making colours.

Hayat said the raw colour came in liquid form and is purchased from Sakinaka, Kurla among other places.

Explaining the process, he said the liquid is filled in plastic bags and allowed to dry. “Once the colour solidifies, we crush it into fine powder and then keep it for drying again. The powder is then filtered and sold in the market,’’ he said.

Hayat, a resident of Bonda district in Uttar Pradesh, comes to Mumbai months before Holi for business. “We sell different shades of colours ranging from Rs 3 per kg to Rs 15 per kg. In this season, we sell around 1,000 kg colours and earn Rs 7,000,’’ he said.

When asked about the legality of his business, Hayat said he had visited the Brihanmumbai Municipal Corporation office but was told there was no need to take permission. Assistant municipal commissioner, G North ward, N V Pai, under whose jurisdiction the area of Mahim causeway falls, said that there was no provision to check on the adulteration of colours. “If the stock is illegal then we can take action. We usually do not take such action but can consider it,’’ he said.

Director of medical education and research of BMC hospitals, Dr M E Yeolekar, said authorities should keep a check on where and how the colours are made. “But even people using colours should keep certain points in mind like applying it on the exterior and not on delicate parts like eyes, ears and the mouth and avoiding ingestion and inhalation as it can be risky,’’ he said, advising people to prefer natural colours or those that come well packed.

Bombay Hospital’s staff physician Dr Ashish Tiwari said the practice in which the colours are made is very harmful. “There should be strict laws to monitor where the colours for Holi are made. These days, colours are made on the footpath and in open places, if people are told in what condition and how they are made, no one will buy them,’’ he said.

Dr Tiwari added that the colours — both dry and the ones mixed with water — contain heavy metals. “Lead, mercury, oxide content in colours can hurt the skin. If it gets into the eye then it can damage the cornea and if it gets into the stomach then there is a possibility of damage to vital organs,’’ he said.