Which of the following additives is typically included in architectural paint to enhance its shelf life by preventing microbial growth, but presents environmental and bio-accumulation concerns?

The following statements (S1 and S2) pertain to paints. S1: With an increase in pigment volume concentration, the gloss increases until the paint becomes flat; blistering also increases. S2: Linseed oil is a widely used vehicle in paints. Identify the validity of the statements as true or false.