Progressives became concerned about long work hours and poor wages damaging the health of factory workers, especially women and children. Reformers like Florence Kelley lobbied for protective legislation. Jacob Riis documented poor living conditions in tenement housing. Muckraking journalists like Ida Tarbell exposed corruption and fraud in big business, such as Standard Oil. Theodore Roosevelt, as president, took steps to regulate industry and break up trusts in the interest of public welfare, while also establishing national parks and promoting conservation. Upton Sinclair's The Jungle drew attention to unsanitary conditions in the meatpacking industry and spurred passage of new food safety laws.