Bright lights being used at a coastal road construction site in Worli is one of the major sources of light pollution in the city, according to a study by environment advocacy group, Awaaz Foundation.

The study records light levels across five locations and highlights the effect of street or high-mast lights, which can especially harm motorists.

Light pollution (measured in lumens or lux) is the collective term for excessively altered, misdirected or obtrusive man-made light. Although there are no global standards for light pollution, doctors said direct exposure to light should not exceed 50-60 lux.

Light levels recorded at the coastal road construction site in Worli was 273 lux; 223 lux at a Haji Ali billboard; 139 lux at a Metro construction site in Churchgate; 65 lux at Bandra station; and 26 lux at the Gateway of India, read the report. The readings were verified independently by optometric experts.

“Blue or white lights at construction sites and billboards are most disturbing as they are high-intensity and direct exposure can cause vision disorders,” said Sumaira Abdulali, convener, Awaaz Foundation. “The lights are placed in a way the glare can lead to fatal accidents at night. This calls for a detailed policy to tackle light pollution.”

While Mumbai Metro Rail Corporation (MMRC) refused to comment, the civic body said lights at Worli were facing the construction site. “Strict guidelines have been issued to our engineers to ensure the lights don’t affect traffic. From 9pm, only a few lights are kept on to ensure safety of our workers,” a civic official said.

A planned lighting installation at the Gateway of India, with even distribution of light sources, does not make it bright, said Abdulali, adding, “It’s an example for the rest of the city.”

Dr Arjun Ahuja, head of ophthalmology department, KEM hospital, Parel, said the impact of light pollution is not easily understood. “People only realise after blurry vision, especially at night. Those living close to work sites must ensure bright lights don’t enter their homes.” he said.

Nilesh Desai, a Kalbadevi resident, who had complained to the civic body about obtrusive lights from gymkhanas and billboards in Marine Drive, said in the absence of a lighting policy, the police and civic officials refuse to register complaints.

First Published: May 11, 2019 02:21 IST