The pollutants known as PCBs (polychlorinated biphenols) may be linked to high blood pressure, a new study reports, adding fuel to the idea that our environments play an important role in our health. PCBs were banned in 1979 for their cancer-causing effects, but prior to this date, the chemicals were used in everything from electrical equipment and thermal insulation to paints and dyes. The chemicals do not break down readily and linger in the soil and water for long periods of time.
They found that people who had the highest PCB levels in their bodies were 3.5 times more likely to have high blood pressure. Even after adjusting for age (which is a significant predictor of high blood pressure), the connection between BCPs and high blood pressure was still there.
Researchers studied residents of Anniston, Alabama, home to a PCB plant years ago. Residents of the city have been found to have higher levels of PCBs in their bodies than the general population.
The researchers defined high blood pressure as being higher than 140/90 mmHg (either one or both of these numbers could be elevated), and included only those people who were not on blood pressure medication. They found that people who had the highest PCB levels in their bodies were 3.5 times more likely to have high blood pressure. Even after adjusting for age (which is a significant predictor of high blood pressure), the connection between BCPs and high blood pressure was still there.
It's still not exactly clear how PCBs affect blood pressure, but the researchers suggest that they may actually affect the genes involved in regulating blood pressure. They add that "[t]here is an urgent need for further study of the role of exposure to these compounds and chronic diseases such as hypertension, cardiovascular disease, and diabetes."
The study was published in the July 19, 2010 online issue of the Journal of Hypertension.