Immunotoxicity of PFAS in highly exposed individuals from Ronneby- autoimmunity, hypersensitivity and immunosuppression.

The immune system is essential to protect us from diseases and when the immune system is impaired, we become ill.

Perfluoralkyl substanses (PFASs) are endocrine disrupting environmental pollutants that are suspected to have a negative impact on the immune system.

This study examines immunotoxicity in individuals highly exposed to PFAS.In 2013 it was discovered that 1/3 of the inhabitants in Ronneby had been exposed to extremely high levels of PFAS via drinking water going back since early 1980s.

Sampling in the population has revealed serum levels over 100 times higher than those found in the general population in Sweden.

PFAS pass from mother to child during both pregnancy and breast-feeding, hence children have been highly exposed during vulnerable developmental periods.

Likewise, those previous exposes will have high level long after the exposure stop due to long half-lives.In this study we analyse adverse effects of PFAS exposure on 1) immunosuppression via infectious diseases and antibody levels to COVID-19 2) hypersensitivity via asthma, allergy and eczema and 3) autoimmunity via celiac disease.

We create a cohort of the total population of Blekinge where some are highly, some mildly and some are unexposed to drinking water and link this to a number of healthcare registers and to the multi-generation register to identify our outcomes.

We analyse antibody levels among verified COVID-19 patients.This is a unique natural experiment with extremely exposed individuals, some already since fetus stage.

The topic is of great public importance, and the EU has highlighted the lack of data on PFAS, while the European Food Safety Authority has recently lowered the levels of tolerable daily intake considerably.

If an association between PFASs and immune function is found, it warrants targets for intervention, and we will collaborate with national and international authorities to reduce exposure to these chemicals.