Impurities in O2 during 2nd Covid wave led to deaths: Study

Chandigarh: Since oxygen was in high demand during the second Covid surge, there were chances of impurities in oxygen during refill. Increase in demand for medical oxygen resulted in impurity and contamination, leading to deaths.

This has been highlighted in a recent editorial published in ‘Environmental Science and Pollution Research’ journal by Drs Vivek Malik, Meenu Singh and Ravindra Khaiwal from the ICMR Advanced Center For Evidence-Based Child Health, department of paediatrics and department of community medicine and school for public health, PGIMER.

To avoid this, ICMR and PGI doctors have recommended oxygen audit and other regulations. “Impurity sources can arise due to production and delivery systems and from environmental pollution. There may be issues in refilling cylinders which can have helium, hydrogen, acetylene, argon gases,” said Dr Vivek.

During the second wave, there were allegations of deaths due to lack of medical oxygen. Oxygen cylinders, oxygen concentrators, liquid oxygen and membrane separator oxygen enrichers have been commonly used.

“In the current Covid pandemic, long-term oxygen therapy is required at both hospitals and in-home settings. The respiratory physician should supervise for optimal treatment. Unprecedented production of oxygen and refilling of cylinders can give rise to the risk of impurities, which could lead to an increase in hidden mortality,” the published article said.

Box: Study recommendations

Monitor gas testing facilities, laboratories and calibration facilities at the site

Ensure compliance and procedures of finished gas for quality

Purity and grade (ultra-pure, 99.999% minimum) should be maintained

Random check of tankers and especially cylinders for chemical analysis of oxygen gases

Impurity parameters certificate should be provided (i.e., carbon monoxide/carbon dioxide, moisture, arsenic, oil, halogen, oxidising substances, acidity or alkalinity, argon, hydrocarbons)

Test results can be cross-checked by the local authority for any foreign materials, moisture, and contaminants

Any misuse of other cylinders (i.e., helium, hydrogen, acetylene, argon) for refilling oxygen without proper cleaning and conditioning should be monitored

Monitoring for sanitisation of oxygen supply (pipeline and tubes) for unwanted fungal growth

Special attention should be given to test mucormycosis infection among recovered patients