Link between environmental pollutants and liver diseases found in Finland
A link has been found between Persistent Organic Pollutants (POPs) and liver diseases in Finland. Humans are exposed to these environmental pollutants mainly through food, such as fish, fruit, and meat and dairy products. POPs include dioxins, polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), perfluoroalkyl and polyfluoroalkyl substances (PFAS).
“While PCBs, which were previously used in various industrial products, and OCPs, used in agriculture, were mostly banned in the 1970s and 1980s, due to their very high stability, they continue to circulate in the environment as a result of old emissions. However, their concentrations are in decline”, says Panu Rantakokko, Research Manager at THL.
“Meanwhile, PFAS are a highly diverse group of chemicals that have been and continue to be widely used in various applications. The bans on the use of PFAS known to be the most harmful to environment and human health have progressed since the turn of the millennium, and their concentrations in the population have also decreased significantly”, Rantakokko continues.
The results were obtained in a joint study by physicians specialised in liver diseases, the Universities of Helsinki and Eastern Finland and the Finnish Institute for Health and Welfare. The study found that the concentrations of POPs measured in blood were linked to marker concentrations indicating the deteriorated condition of the liver. During a follow-up period of approximately eight years after POP concentration measurements, a link was observed between these environmental pollutants and an increased risk of hospitalisation caused by liver disease, development of liver cancer or death due to liver disease.
POPs have several known adverse effects on human health. Previous cell and animal testing has shown that high exposures to POPs cause various liver dysfunctions. However, relatively few studies have focused on the risks of low human exposure.
The research data included measurements of serum samples from 2,789 adults who participated in the Healthy Finland 2007 study, health surveys and the participants’ disease data obtained from the registers after 2007.
Liver disease risk increases particularly in combination with other risk factors
The link between high POP levels and later liver disease was clearest among the research subjects who also had other risk factors for liver disease, such as overweight, high alcohol consumption or whose liver condition had already deteriorated. However, the link between many POPs and liver damage also remained when the impact of health problems typical of liver diseases, such as overweight, diabetes and smoking were excluded.
Due to the nature of the study, it is difficult to establish a certain causal link between exposure to POPs and liver diseases. However, the results of the study provide grounds for implementing further, more detailed biochemical and toxicological studies on the observed links. They can be used to determine whether POPs activate similar liver damage mechanisms in humans as those observed in animal studies.
Reference:
Thl.fi: Environmental pollutants
Contact information:
Panu Rantakokko
Research Manager
Tel. +358 29 524 6395
email: [email protected]
