Exposure to culturable microorganisms in paper mills and presence of symptoms associated with infections

Mini-review: microbial problems in paper production

Paper mills are open systems, which provide favorable conditions for microbial growth. Microbial contamination can cause substantial economic losses, including the deterioration of raw materials, interference with production processes by breakdowns and lowering product quality, and eventually, problems in wastewater treatment. Damage is caused by acidification, attack on raw materials, the formation of odorous products, discoloration of pigments, and the formation of methane and hydrogen, thereby producing potentially explosive conditions. Population analyses have revealed that a wide variety of microorganisms are involved, but there appear to be no typical strains associated with paper mills. Current trends in process engineering, such as chlorine-free bleaching, processing at neutral pH, closed cycles, and the use of recycled paper also favor microbial growth and biofilm (slime) formation. A fundamental problem associated with slimes is the extensive matrix of extracellular polymeric substances, which is composed of a large variety of highly hydrated polysaccharides, proteins, nucleic acids, and lipids. No 'silver bullet' against biofouling can be expected, and effective countermeasures have to be based on holistic approaches.

Proximity to pulp and paper mills and wheezing symptoms among adolescents in North Carolina

Using data from the North Carolina School Asthma Survey about the respiratory health of 64,432 adolescents attending public schools in North Carolina and data provided by school employees about the environmental health conditions of the school buildings, we assessed the prevalence of daytime wheezing during the past year among students estimated to be exposed to air pollutants arising from pulp and paper mills located near the schools. Of the schools the students attended, 14% (37/266) were located within 30 miles of one or more pulp and paper mills and odor from the mills was identified by survey respondents for 9 of the 266 schools. The prevalences of daytime wheezing in smokers and nonsmokers with household cigarette smoke exposure were elevated among students attending schools located within 30 miles of a pulp and paper mill, compared to the prevalence among students attending schools located beyond 30 miles (10 miles, prevalence ratio (PR): 1.21, 95% confidence interval (95% CI): 0.99, 1.43; 10-30 miles, PR: 1.06, 95% CI: 0.96, 1.16) and among students attending schools with noticeable odor from a pulp and paper mill (PR: 1.12, 95% CI: 0.93, 1.31). These results indicate a possible association between paper mill location and wheezing symptoms among adolescents and suggest that community-based exposure to pulp and paper mill emissions may have a greater impact on smokers and individuals exposed to cigarette smoke in the home than on nonsmokers without such household exposure.