title: Risk of multiple sclerosis is not associated with exposure to crude oil, but increases with a low level of education.
authors.forename: Hongliang
authors.initials: H
authors.lastname: Zhang
mesh_terms: D004522:Educational Status; D019652:Extraction and Processing Industry; D005260:Female; D006801:Humans; D008297:Male; D009103:Multiple Sclerosis / Q000209:etiology*; D009784:Occupational Diseases / Q000209:etiology*; D016273:Occupational Exposure; D010578:Petroleum / Q000009:adverse effects*
chemical_list: D010578:Petroleum