title: Airborne emissions of carcinogens and respiratory sensitizers during thermal processing of plastics.
abstract: OBJECTIVE
  Thermoplastics may contain a wide range of additives and free monomers, which themselves may be hazardous substances. Laboratory studies have shown that the thermal decomposition products of common plastics can include a number of carcinogens and respiratory sensitizers, but very little information exists on the airborne contaminants generated during actual industrial processing. The aim of this work was to identify airborne emissions during thermal processing of plastics in real-life, practical applications.
  
  
  METHODS
  Static air sampling was conducted at 10 industrial premises carrying out compounding or a range of processes such as extrusion, blown film manufacture, vacuum thermoforming, injection moulding, blow moulding, and hot wire cutting. Plastics being processed included polyvinyl chloride, polythene, polypropylene, polyethylene terephthalate, and acrylonitrile-butadiene-styrene. At each site, static sampling for a wide range of contaminants was carried out at locations immediately adjacent to the prominent fume-generating processes.
  
  
  RESULTS
  The monitoring data indicated the presence of few carcinogens at extremely low concentrations, all less than 1% of their respective WEL (Workplace Exposure Limit). No respiratory sensitizers were detected at any sites.
  
  
  CONCLUSIONS
  The low levels of process-related fume detected show that the control strategies, which employed mainly forced mechanical general ventilation and good process temperature control, were adequate to control the risks associated with exposure to process-related fume. This substantiates the advice given in the Health and Safety Executive's information sheet No 13, 'Controlling Fume During Plastics Processing', and its broad applicability in plastics processing in general.
authors.affiliation: Health and Safety Laboratory, Harpur Hill, Buxton, Derbyshire, SK17 9JN, UK. john.unwin@hsl.gov.uk
authors.forename: John
authors.initials: J
authors.lastname: Unwin
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Coldwell
authors.forename: Chris
authors.initials: C
authors.lastname: Keen
authors.forename: John J
authors.initials: JJ
authors.lastname: McAlinden
mesh_terms: D000181:Acrylonitrile / Q000633:toxicity; D002070:Butadienes / Q000633:toxicity; D002273:Carcinogens / Q000032:analysis*; D006801:Humans; D007221:Industry; D019570:Inhalation Exposure / Q000032:analysis / Q000517:prevention & control; D016273:Occupational Exposure / Q000032:analysis; D052638:Particulate Matter / Q000032:analysis*; D010969:Plastics / Q000009:adverse effects / Q000737:chemistry* / Q000633:toxicity; D020959:Polyethylene / Q000633:toxicity; D011126:Polypropylenes / Q000633:toxicity; D020058:Styrene / Q000633:toxicity; D044366:Transition Temperature
chemical_list: D002070:Butadienes; D002273:Carcinogens; D052638:Particulate Matter; D010969:Plastics; D011126:Polypropylenes; D020058:Styrene; D020959:Polyethylene; D000181:Acrylonitrile