C sharp - Perdida de memoria c#

for (int documents = 0; documents <= doc.Count - 1; documents++)

{

    object i = doc[documents][0];

    int ide = Convert.ToInt32(i);

    object nombreA = doc[documents][1];

    string nombreArchivo = (string)nombreA;

    object icono = doc[documents][6];

    byte[] icon = (byte[])icono;

    MemoryStream memStream = new MemoryStream();

    memStream.Write(icon, 0, icon.Length);

    image = System.Drawing.Image.FromStream(memStream);

    object titulo = doc[documents][3];

    string title = (string)titulo;

    object subtitulo = doc[documents][4];

    string subtitle = (string)subtitulo;

    PictureBox pb = new PictureBox();

    pb.Size = new System.Drawing.Size(150, 150);

    pb.SizeMode = PictureBoxSizeMode.StretchImage;

    pb.Image = image;

    pb.Name = ide.ToString();

    contenedor.Controls.Add(pb); /////////////////////////////fuera de memoria   

    int tmp = contenedor.Controls.Count;

    memStream.Close();

    memStream.Dispose();

    image = null;

    Dispose(true);

}