Chemical contamination that increases the risk of COVID-19

Having high levels of certain chemical contaminants in the blood has been linked to an increased risk of SARS-CoV-2 infection and developing COVID-19.

This has been established in a study conducted by researchers from the Hospital del Mar Medical Research Institute in Barcelona (IMIM), the Barcelona Institute for Global Health (ISGlobal, a center promoted by the “la Caixa” Foundation), the University of Las Palmas, and the Network of Biomedical Research Centers CIBERESP (Epidemiology and Public Health), CIBEROBN (Obesity and Nutrition) and CIBERINFEC (Infectious Diseases), in Spain.

This is the first prospective study in the world to analyze data obtained before the pandemic on blood levels of pollutants in healthy people.

The results of this work provide a possible new explanation for the large differences in susceptibility to SARS-CoV-2 infection and to COVID-19. Why do some people get infected with the virus under similar exposure conditions and others don’t? Why do some develop the disease and others do not? Today, these observations and questions remain largely without sufficient scientific explanation. “What the study finds is that some of these contaminants increase the risk of being HIV positive and getting the disease,” said Miquel Porta, one of the study’s lead authors, a researcher at the Hospital del Mar Medical Research Institute. and head of the group of CIBERESP. Other factors that influence these differences between people are the illnesses a person already suffered from (the more comorbidities, the higher the risk of COVID-19), smoking, age, level of education, the density of people in a home or exposure to the environment. virus in public transport or at work.

In 2016, the researchers had frozen blood samples from 154 healthy people from the general population of Barcelona. They correlated the levels of contaminants in these people with the frequency of SARS-CoV-2 infection and the incidence of COVID-19 in 2020-2021 in the same people. And they found that in cases with higher blood levels of some contaminants, the risk of infection and developing the disease was higher. With regard to the risk of COVID-19, those responsible are DDD and DDE, derived from the insecticide DDT, as well as lead, thallium, ruthenium, tantalum, benzo(b)fluoranthene and manganese. The risk of infection was higher with higher blood levels of thallium, ruthenium, lead and gold, while it was lower with higher concentrations of iron and selenium. “Another highly relevant finding of the study is that it identifies mixtures of up to five substances from different chemical groups that increase the stated risks,” added Gemma Moncunill, a researcher at ISGlobal and CIBERINFEC; and co-author of the study.

From left to right: Miquel Porta, Laura Campi, José Pumarega and Magda Gasull, from the research team. (Photo: IMIM/CIBER)

The study authors believe these results have significant scientific and societal relevance and provide the first prospective, healthy general population-based evidence of a possible link between personal concentrations of some pollutants and COVID-19.

These contaminants reach our bodies through multiple routes, such as electronic devices and their use in feed in intensive livestock farming. If the associations found are confirmed to be causal, measures will therefore have to be taken in those areas to manage the associated risks.

The study is titled “Individual blood concentrations of persistent organic pollutants and chemical elements, and COVID-19: a prospective cohort study in Barcelona”. And it’s published in the scientific journal Environmental Research. (Source: IMIM/CIBER)