Conclusion: Higher PON1 activity is associated with decreased oxLDLlipids levels, but not with oxHDLlipids in a population of young Finnish adults. These findings support the suggestion that PON1 activity may have a role in the oxidation of LDL lipids. There is a strong association between PON1 rs662 polymorphism and PON1 activity, but PON1 rs662 polymorphism is not associated with oxidized lipoprotein lipids and oxLDLprot. (C) 2015 Elsevier Ireland Ltd. All rights reserved.