Вот набрала в гугле про вред https://www.google.ru/search?newwindow=1&ei=vreLXLjuPJmIk74PnaqngAM&q=%D0%BF%D1%80%D0%BE%D0%B8%D0%B7%D0%B2%D0%BE%D0%B4%D1%81%D1%82%D0%B2%D0%BE+%D0%B2%D0%B8%D1%82%D0%B0%D0%BC%D0%B8%D0%BD%D0%BE%D0%B2+%D0%B2%D1%80%D0%B5%D0%B4&oq=%D0%BF%D1%80%D0%BE%D0%B8%D0%B7%D0%B2%D0%BE%D0%B4%D1%81%D1%82%D0%B2%D0%BE+%D0%B2%D0%B8%D1%82%D0%B0%D0%BC%D0%B8%D0%BD%D0%BE%D0%B2+%D0%B2%D1%80%D0%B5%D0%B4&gs_l=psy-ab.3...4062.5838..7240...0.0..0.229.861.0j4j1......0....1..gws-wiz.......0i203j0i22i30j33i160.5B0mUlWkLrcПока ничего страшного не нашла.