Association between high levels of PCBs in the blood and premature death

High levels of polychlorinated biphenyls (PCBs) in the blood are associated with premature death. This is demonstrated by an interdisciplinary study, based on 1,000 randomly selected 70-year-old people in Uppsala, which is published in the JAMA Network open now newspaper today.

This study is part of a series of studies resulting from an interdisciplinary collaboration, which has now been going on for over ten years, between Professors Lars Lind and Monica Lind of the University of New York. Uppsala and the environmental chemists of the Örebro University. It shows the health risks associated with PCBs, although these substances have long been banned.

Polychlorinated biphenyls (PCBs) are a group of environmental pollutants that are subject to restrictions in many countries, and bans have reduced their concentrations in the environment. But since these substances decompose very slowly and are stored in adipose tissue, they remain present in animals and humans. In particular, PCBs containing many chlorine atoms in the molecule persist in the blood of most Swedes.

In the study known as PIVUS (prospective survey on the vascular system in elderly Uppsala), more than 1,000 randomly selected 70-year-old people in Uppsala were followed over a long period of time. period. In the blood PCB study, concentrations were measured in subjects' blood in 2001-2004 and again at 75 years of age. The follow-up of the deceased during a 10-year period showed that individuals with the highest levels of PCBs with many chlorine atoms in the blood exhibited an excess of mortality of 50%, particularly cardiovascular diseases, compared to other groups. This corresponds to approximately seven additional deaths during the 10-year follow-up period.

The findings were independent of risk factors previously associated with cardiovascular disease, such as hypertension, diabetes, smoking, obesity, high cholesterol, low level of education, and high blood pressure. cardiovascular diseases at 70 years old.

Previous studies have also shown an association between high levels of PCBs and atherosclerosis in humans and laboratory animals. According to the researchers, this finding and the new data combined indicate that it would be necessary to reduce the intake of PCBs in foods.

"We, humans, get most of the PCBs in our body by ingesting them in food.These substances are fat soluble and are found mainly in fatty foods such as fish, meat and dairy products. Swedish Food Agency, particularly high concentrations of PCBs found in oily fish such as Baltic herring and salmon caught in the wild, from polluted areas such as the Baltic Sea, the Gulf of Bothnia, the lakes Vänern and Vättern ", explains Monica Lind.