SJWEH Supplements are open access, (mostly) non-peer-reviewed articles usually published in theme issues or as part of a series of papers from a conference or workshop. Scand J Work Environ Health stopped publishing SJWEH Supplements in 2009.

Discussion paper

SJWEH Supplements 2009;(no 7):36-40    pdf

Does endotoxin exposure affect lung function and induce systemic inflammation in workers handling bacterial single cell protein?

by Skogstad M, Sikkeland LIB, Øvstebø R, Foss Haug KB, Kierulf P, Kulvik Heldal K, Kongerud J, Eduard W

Objective Bioprotein or bacterial single-cell protein (SCP) consists of dry bacterial biomass mainly of a single gram-negative species, which contains endotoxins. Used as animal feed, bioprotein was produced in a biotechnology plant in Norway from 1999 until 2006, when the plant was closed down. This paper summarizes four previously published studies, where we aimed to explore the inflammatory effects of endotoxin exposure from bacterial SCP on the plant employees.

Methods Most of the 28 workers that were examined in 2003 and 2005, among them five women, worked full-time at the plant. We collected blood, measured lung function, and performed sputum analysis.

Results Our previous findings showed that exposure to endotoxins exceeded 200 endotoxin units/m3 in 80% of the measurements. During a work shift in 2003, significant decreases in forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were detected along with an increase in the white blood cell count and serum IL-6 (interleukin-6). In 2005, compared to a control group, an abundance of neutrophils was detected in the sputum of the workers handing bioprotein in addition to circulating lipopolysaccharides (LPS) and increased inflammatory markers in plasma.

Conclusion Prolonged exposure to bacterial SCP, resulting in inhalation of endotoxin into the blood, is probably the cause of inflammatory responses in the lung and blood.

The following article refers to this text: 2009;0 suppl 7:3-4