We have previously seen that PFAS can affect our immune system. Since the immune system plays a role in the development of asthma, we wanted to investigate how PFAS affects the risk of asthma.
Annelise Blomberg, researcher in occupational and environmental medicine at Lund University, says.
27 percent of children born to mothers exposed to very high levels of PFAS in drinking water during pregnancy developed asthma. Among children born to mothers with low exposure, the proportion was 16 percent.
We cannot definitely state that PFAS causes asthma; we can only say that we see a connection.
Annelise Blomberg says.
Can cross the placenta
In 2013 it was discovered that the drinking water in Kallinge in Ronneby municipality had high levels of PFAS. The contamination came from fire-fighting foam used during fire drills at Regiment F 17.
Since PFAS can cross the placenta, the fetus is also exposed if the mother drinks water containing PFAS. However, precise explanations of how the long-lived PFAS chemicals affect the body are lacking.
The effects of PFAS on our bodies are quite complex. We know that it can affect many things in the body, such as cholesterol levels, the immune system and birth weight. But it is difficult to say what it is that leads to all these effects.
Annelise Blomberg says.
Great interest
The study includes more than 11,000 children born in Blekinge from 2006 to 2013. The researchers used the mothers' residential addresses five years before giving birth. The women who had lived in Kallinge for all five years before giving birth are considered in the study to have had very high PFAS exposure. The children of these women were then compared with other children in Blekinge.
Annelise Blomberg believes there could be significant interest in the results.
It is of course important for those who have been exposed in Ronneby, but also for others who have been exposed, not only in Sweden but around the world.
Annelise Blomberg says.
The study is published in the scientific journal PLOS Medicine.
Facts: The study
The prevalence of asthma in 11,488 children born in Blekinge between 2006 and 2013 has been examined up to the age of twelve.
The children were divided based on how much their mothers were assessed to have been exposed to PFAS five years before birth:
Very high exposure: 194 children (whose mother had lived at an address with heavily PFAS-contaminated drinking water for all five years before giving birth).
High exposure: 479 children (whose mother had lived at such an address for at least one of the five years before giving birth).
Average: 1,591 children (whose mother had lived in Ronneby municipality, but not at an address with heavily PFAS-contaminated drinking water).
Background group: 9,224 children (whose mother lived in Blekinge, but not in Ronneby municipality).
During the follow-up period, 16 percent of the children in the background group with low exposure developed asthma, compared with 27 percent in the group with very high PFAS exposure.
No increased incidence of asthma was seen in children whose mothers had high PFAS exposure during pregnancy.
Source: Lund University
PFAS are man-made chemicals that break down very slowly. They are known as persistent chemicals and accumulate in nature and in our bodies.
PFAS are used, for example, in coolants, impregnation agents, fire-fighting foam, cosmetics, packaging and in plant protection products used in agriculture.
According to studies, PFAS substances can affect birth weight, blood cholesterol levels and liver enzymes, as well as cause a reduced antibody response after vaccination.
Source: Swedish Chemicals Agency, Swedish Food Agency
