Exposure to airborne microorganisms and endotoxin in a potato processing plant. (49/383)

Microbiological air sampling was performed in a big potato processing plant located in eastern Poland. Air samples for determination of concentrations of microorganisms, dust and endotoxin were collected at 6 sites in the division producing potato flakes and meal from dried potato pulp and at 2 sites in the division producing potato syrup from imported starch. The concentrations of total airborne microorganisms were within a range of 28.3-93.1 x 10(3) cfu/m(3). Mesophilic bacteria were dominant at all sampling sites, forming 73.1-98.8% of the total count. Among them, distinctly prevailed corynebacteria (irregular Gram-positive rods) that accounted for 54.3-81.1% of the total airborne microflora. The most common were strains of Corynebacterium spp., followed by strains of Arthrobacter spp., Microbacterium spp., and Agromyces ramosus. The latter species, so far not reported from the air of occupational environments, abundantly develops in the parenchyma of potato tubers. Its airborne concentration increased rapidly after peeling of potatoes, and attained maximal values at cutting and blanching (steaming and sulfuration) of potatoes, and at sacking of potato meal. The proportions of Gram-negative bacteria and endospore-forming bacilli were low, respectively 0.6-7.6% and 2.0-8.1% of total count. Fungi constituted 1.2-26.9% of total count. The dominant species was Aspergillus niger that formed 99.8% of total airborne fungi. The values of the respirable fraction of airborne microflora varied between 25.3-73.2%. The concentrations of airborne dust were 1.4-26.6 mg/m(3) in the division producing potato flakes and meal and 114.9-200.5 mg/m(3) at pouring of potato and corn starch for syrup. The concentrations of airborne endotoxin were in the range of 0.011-0.089 microg/m(3) during the initial stages of potato processing (unloading, washing, peeling) and drastically increased after blanching to the extraordinarily high levels of 45.9-1893.9 microg/m(3). At pouring of starch for syrup, the concentrations of airborne endotoxin were much lower, within a range of 0.029-0.156 microg/m(3). In conclusion, the workers of potato processing facilities could be exposed to large concentrations of microorganisms, dust and endotoxin posing a risk of work-related respiratory disease.  (+info)

Precipitin response of potato processing workers to work-related microbial allergens. (50/383)

Serum samples from 61 potato processing workers and 30 urban dwellers not exposed to organic dusts (as a reference group) were examined in agar-gel precipitation test performed by Ouchterlony double diffusion method with the antigens of 12 microorganisms associated with organic dusts. Each serum was tested twice: not concentrated, and three-fold concentrated, for the detection of low levels of precipitins. The antibody response of workers to the antigen of coryneform bacterium Agromyces ramosus was high, at both not concentrated and 3-fold concentrated sera (respectively 29.5% and 45.9%)--significantly greater than in reference group (p < 0.001). Workers' response to the antigens of Gram-negative bacterium Alcaligenes faecalis and thermophilic actinomycete Thermoactinomyces vulgaris was lower (respectively 13.1% and 13.1% at not concentrated sera, 24.6% and 29.5% at 3-fold concentrated sera) but in all cases significantly greater than in reference group (p < 0.05 at not concentrated sera, p < 0.01 and p < 0.001 at 3-fold concentrated sera). The frequency of positive precipitin reactions of potato workers to antigen of Penicillium citrinum was high only at 3-fold concentrated sera (55.7%)--significantly higher compared to reference group (p < 0.001). The antibody response of potato workers to other antigens was either unspecific or low, showing no significant difference compared to reference group. Twenty eight out of 61 examined potato processing workers (45.9%) reported the occurrence of the work-related pulmonary symptoms. The frequency of positive precipitin reactions to Agromyces ramosus, Alcaligenes faecalis, Thermoactinomyces vulgaris, Penicillium citrinum and Acinetobacter calcoaceticus was significantly greater in the subgroup of 28 workers reporting work-related pulmonary symptoms compared to 33 asymptomatic workers (p < 0.05). Study results suggest that antigens of Agromyces ramosus, Alcaligenes faecalis, Thermoactinomyces vulgaris and Penicillium citrinum should be considered as potential occupational allergens, probably stimulating an adverse immunopathological reaction in the exposed potato processing workers.  (+info)

The effects of exposure to organic dust on the respiratory system of potato processing workers. (51/383)

A cross-sectional study was carried out to evaluate lung function and the prevalence of work-related symptoms in workers of a potato processing plant located in Lublin region (eastern Poland). The study group comprised 61 workers employed in 2 departments. The examination included: physician-administrated questionnaire on occurrence of work-related symptoms, occupational history and smoking habits. Spirometry was performed before (7:00-8:00) and after (16:00-17:00) the morning shift. Altogether 41/61 (67.2%) subjects reported at least one symptom associated with their job. Pulmonary symptoms were recorded in 28/61 (45.9%) subjects. The most commonly recorded complaints were: cough (44.3%), hoarseness (19.7%), shortness of breath (18%), followed by headache and skin lesion (13.1% each), and eye and nose irritation (11.5%). The prevalence of work-related symptoms (except for eye and nose irritation) was higher in the group of subjects working longer than 4 years (the difference was statistically significant only for skin lesion). Among non-smoking workers a significantly higher prevalence of headache was seen compared to smokers (Fisher's test, p < 0.05). Smokers complained more frequently of respiratory symptoms such as cough, shortness of breath, hoarseness and chest pain. The difference was significant only for cough (p < 0.05). A statistically significant over-shift decline in all measured spirometric values: FVC, FEV(1) (p < 0.001), FEV(1)/VC (p < 0.05), PEF (p < 0.01) was observed.  (+info)

A food-grade approach for functional analysis and modification of native plasmids in Lactococcus lactis. (52/383)

While plasmids from lactic acid bacteria possess many traits that are of industrial value, their exploitation is often frustrated by an inability to conduct food-grade engineering of native plasmids or to readily screen for their transfer. Here we describe a system that uses a RepA(+) temperature-sensitive helper plasmid and a RepA(-) cloning vector to overcome these problems while maintaining the food-grade status of the native plasmid. This strategy was used to precisely delete ltnA1 alone, or in conjunction with ltnA2 (encoding the structural proteins of the lantibiotic lacticin 3147), from the native 60.2-kb plasmid pMRC01 and to select for the transfer of pMRC01 between Lactococcus lactis strains.  (+info)

Salmonella and campylobacter contamination of raw retail chickens from different producers: a six year survey. (53/383)

Between 1995 and 2000, a prospective survey was undertaken to investigate the levels of contamination of raw retail chickens (n = 1,127) with salmonella and campylobacter. The levels of contamination over the 6-year period were 11 % (95 % CI +/- 6.5%) for salmonella, and 57% (95% CI +/- 95%) for campylobacter. S. Bredeney (20%) and S. Enteritidis (18%) were the dominant serovars. Although salmonella contamination was higher than in an earlier survey we conducted (7%), since 1998 it has declined to 6%. Many S. Enteritidis isolates (43%) were associated with one large integrated poultry organization that appears to have successfully managed the contamination, and the serovar has not been isolated since 1998. Contamination ranged from 0 to 44% between different producers. There was no significant difference between producers contributing large and small numbers of samples, although some small producers had much poorer contamination rates than others. S. Bareilly, S. Bredeney, S. Enteritidis and S. Virchow showed associations with particular producers. Campylobacter contamination remains high. Contamination ranged from 47 to 81% between different producers. This study did not show a temporal association between contamination of chickens and human campylobacter infections, indicating that many cases of human campylobacteriosis, particularly during seasonal peaks, do not originate from chickens. Control measures that have reduced salmonella contamination have been largely ineffective against campylobacter and new interventions are needed. Most raw chickens are contaminated with these pathogens, and communicating the importance of minimizing this risk to caterers and the public is vital in reducing human infections.  (+info)

A case study of sodium reduction in breakfast cereals and the impact of the Pick the Tick food information program in Australia. (54/383)

In 1997, one of Australia's largest food companies undertook a program of salt reduction in 12 breakfast cereals. The National Heart Foundation's Pick the Tick program criterion (<400 mg sodium per 100 g) was used as a target value where possible. Twelve products were reformulated, with reductions ranging from 85 to 479 mg sodium per 100 g and an average reduction of 40% (12-88%). As a result, 235 tonnes of salt were removed annually from the Australian food supply and five more products were able to carry the tick logo. The impact of the Pick the Tick program in changing the food supply extends beyond those products that are part of the food approval program.  (+info)

A global response to a global problem: the epidemic of overnutrition. (55/383)

It is estimated that by 2020 two-thirds of the global burden of disease will be attributable to chronic noncommunicable diseases, most of them strongly associated with diet. The nutrition transition towards refined foods, foods of animal origin, and increased fats plays a major role in the current global epidemics of obesity, diabetes and cardiovascular diseases, among other noncommunicable conditions. Sedentary lifestyles and the use of tobacco are also significant risk factors. The epidemics cannot be ended simply by encouraging people to reduce their risk factors and adopt healthier lifestyles, although such encouragement is undoubtedly beneficial if the targeted people can respond. Unfortunately, increasingly obesogenic environments, reinforced by many of the cultural changes associated with globalization, make even the adoption of healthy lifestyles, especially by children and adolescents, more and more difficult. The present paper examines some possible mechanisms for, and WHO's role in, the development of a coordinated global strategy on diet, physical activity and health. The situation presents many countries with unmanageable costs. At the same time there are often continuing problems of undernutrition. A concerted multisectoral approach, involving the use of policy, education and trade mechanisms, is necessary to address these matters.  (+info)

Heterologous expression of the Saccharomyces cerevisiae PGU1 gene in Schizosaccharomyces pombe yields an enzyme with more desirable properties for the food industry. (56/383)

The Saccharomyces cerevisiae PGU1 gene was successfully expressed in Schizosaccharomyces pombe. The optimum pH and temperature for the recombinant enzyme were 5 and 40 degrees C, respectively, these being around 0.5 U higher and 5 degrees C lower than those shown by the native enzyme. The K(m) value was about fourfold higher than that of the S. cerevisiae enzyme. The recombinant endopolygalacturonase was more efficient in reducing the viscosity of polygalacturonic acid and was also more stable at different pHs and temperatures than the native enzyme.  (+info)