Disinfectant tunnels installed in more places, but are they safe? Experts raise doubts

As cases of coronavirus continue to rise in Tamil Nadu, taking its toll on the state’s healthcare system, the local administration is looking for new ideas to halt the spread of the virus. Following in the path of the Tiruppur Corporation, the Greater Chennai Corporation (GCC) has now set up a disinfection tunnel at a market in the city.

The tunnel, which opened to the public on Wednesday morning in Thiruvanmiyur market, sprays water mixed with Lysol at those who pass through it. The tunnel is 20-feet-long and five-feet wide.

Speaking to TNM, a senior officer at the GCC says, “We are planning to set up one more tunnel in the market itself since we realised many people visit to buy essentials,” he said.

When asked about the efficacy of the disinfectant mix, the officer said it was only an added precaution and not the only precautionary measure that should be taken. “Nothing can substitute handwashing. We have a handwash point at the entrance of the tunnel, which people are supposed to use before entering the tunnel,” he explained.

The GCC will primarily use the watered-down version of Lysol in its disinfectant tunnels as feedback from users has been positive and no side effects have been reported, according to the corporation’s team of health officials.

Criticism around use of Sodium Hypochlorite

Aside from Chennai, other cities in Tamil Nadu like Tiruppur and Thrissur in Kerala, have also installed disinfection tunnels in markets, where a solution of Sodium Hypochlorite is sprayed in a mist on people who pass through it. However, the concentration levels are not uniform and vary from anywhere between 0.2% and 1%.

The Tiruppur Corporation had inaugurated its disinfection tunnels last week in a busy market area in the city as a precautionary measure. As per a report in The Hindu, the tunnel will spray 1% Sodium Hypochlorite solution per 1ppm (parts per million) on those who pass through.

Meanwhile, the tunnel in Sakthan market in Thrissur has 0.20% Sodium Hypochlorite solution in it, according to Thrissur Mayor Ajitha Jayarajan.

However, a professor of community medicine at a private medical college in Chennai explained that though Sodium Hypochlorite is a known disinfectant used in surgical equipment, its effect on human skin is not known.

Anant Bhan, a global health researcher, also noted that the effects of using Sodium Hypochlorite or Lysol on people is not yet known. “It is not clear if the mixture that is being used in the tunnel has any negative effect on the health of the people walking through the tunnel. What happens when they inhale those?” he questioned.

Adding that tunnels like these might end up providing a false sense of protection to people, he said, “If I have COVID-19 infection, it is in my lungs. How is a surface disinfection going to stop the virus from spreading from me to others?”

He also added that there are a lot of questions to be answered before relying on these initiatives. “How long should we be exposed for the disinfectant to work? What concentration of Sodium Hypochlorite do we need to use? These are open-ended questions for which we need studies to rely on,” he added. 

With inputs from Neethu Joseph