The lecture purpose: To acquaint students with the hygienic characteristic of chemical production factors and measures of preventive maintenance of their harmful influence on the body of the working. Specific actions on the body of working production factors are considered (allergenic, cancerogenic, mutagen, teratogenic, embryotoxic), corresponding preventive maintenance measures are characterized. The concept of treatment-and-prophylactic food of harmful factors working under the conditions of influence, its appointment, types, and legal basis in the Republic of Uzbekistan are presented.