The research aims to understand oceans as crucial contributors to human health in coastal environments. Oceans produce marine spray aerosols that contain a mixture of microbiota and natural biological molecules (biogenics).

The primary outcome envisioned consists of 2 goals.

1. In this study, the first objective is to determine whether the microbiota and biogenic molecules found in sea air are also found in the nasal swabs of the participants. In this way, the investigators will gain an understanding of which sea air components are inhaled by humans and how this changes over time. Besides, the difference in microbiome between the inland and coastal population will be investigated.
2. Second, the investigators want to get an idea of whether these inhaled sea air components have an effect on certain pathways in the human body. In the in vitro study with cell lines, effects were already seen of sea air exposure on certain pathways in the body. Now the second goal of this study, is to see if changes in immunity biomarkers are seen in vivo in humans. The Investigators will do this by taking VAMS blood samples from the participants.

Inclusion Criteria:

• healthy participants between 18 and 50 years old

Exclusion Criteria:

• people with a medical condition
• people younger than 18 and older than 50