Exposure to flour dust in UK bakeries: current use of control measures

In May 2001, a maximum exposure limit (MEL) for flour dust was set in the UK at 10 mg/m(3) [8 h time-weighted average (TWA)] with a short-term exposure limit (STEL) of 30 mg/m(3) (15 min reference period). The purpose of this study was to produce a benchmarking baseline of current control measures and exposure levels, in addition to assessing the provision of training and the knowledge of the UK regulations amongst the bakeries.

A total of 208 long-term personal inhalable dust samples (8 h TWA) were collected from workers in 55 bakeries (covering a wide range of industry types and sizes) between October 2002 and December 2003 in England, Wales and Scotland. Standardized occupational hygiene reports were produced for each establishment to provide information about the site (such as the size of the bakery) and the control measures employed (including ventilation, good working practices, knowledge of UK regulations and the extent of training provided).

Median inhalable dust exposure (8 h TWA) for the bakery workers was 3.7 mg/m(3) (75th percentile at 7.7 mg/m(3)) and 17% of the dust results exceeded the MEL. Although information about the MEL has been available in the trade press and through recognised trade associations, only 27% of the bakeries were aware of the MEL and STEL. Mixed model regression analysis suggested that determinants of higher exposure included the job category (particularly weighing/sieving or mixing), medium to large bakery size (50 or more employees) and bakeries being located in Scotland. However, having an appointed safety representative was associated with lower exposure.

The conclusions derived here are based upon the use of a statistical model, but clearly, if bakeries and individuals employ good working practices, with correct use of local exhaust ventilation, they should be able to comply with the MEL.