Air pollution exposure is a major environmental and public health concern. The findings from controlled exposure studies have given biological plausibility to the epidemiological associations, and have defined important pathways that may be amenable to intervention. Ultimately, there is a need to address how one may protect the public from these detrimental effects. Two studies have been performed assessing the cardiovascular effects of wearing a face mask in a highly polluted urban area in China in healthy volunteers and patients with coronary heart disease. These demonstrated lower blood pressure and increased heart rate variability when wearing a face mask as compared to not. The investigators aim to test if wearing a highly efficient face mask during exposure to dilute diesel exhaust abrogates the well-known adverse cardiovascular effects.

Inclusion Criteria:

• Healthy males
• Non-smoking
• All subjects undergo a general health examination and are required to have normal clinical examination, ECG, blood tests and lung function

Exclusion Criteria:

• Metabolic or cardiovascular disease
• Asthma or other respiratory disease
• Respiratory infection within 2 weeks of the study
• Antioxidant- and/or vitamin supplementation within 1 week prior to, as well as during the course of the study. (incl vitamin C, Acetylcysteine)
• Smokers or regular snus usage