Methanotrophy, Methylotrophy, the Human Body and Disease

Methylotrophic Bacteria use one-carbon (C1) compounds as their carbon source. They have been known to be associated to the human body for almost 20 years as part of the normal flora and were identified as pathogens in the early 1990s in end-stage HIV patients and chemotherapy patients. In this chapter, I look at C1 compounds in the human body and exposure from the environment and then consider Methylobacterium spp. and Methylorubrum spp. in terms of infections, its role in breast and bowel cancers; Methylococcus capsulatus and its role in inflammatory bowel disease, and Brevibacterium casei and Hyphomicrobium sulfonivorans as part of the normal human flora. I also consider the abundance of methylotrophs from the Actinobacteria being identified in human studies and the potential bias of the ionic strength of culture media and the needs for future work. Within the scope of future work, I consider the need for the urgent assessment of the pathogenic, oncogenic, mutagenic and teratogenic potential of Methylobacterium spp. and Methylorubrum spp. and the need to handle them at higher containment levels until more data are available

Occupational exposure level of pig facility workers to chemical and biological pollutants

Objective. The aim of the study was to assess the impact of a fattening season on the level of airborne chemical and microbial pollutants in the pig fattening house. Materials and method. Evaluation of the air composition as well as the microbiological air quality were made during 2 series, i.e. in the summer and winter period of fattening. Airborne gaseous pollutants were analyzed by gas (organic compounds) and liquid (inorganic compounds) chromatography methods. Air microbial contamination was determined in compliance with the Polish Standard PN-EN 13098:2007. Results. The air/gas composition in the pig unit showed that irrespective of the fattening season, the level of determined pollutants – especially ammonia, volatile organic compounds (VOCs), including methanethiol and total dust – could have an adverse effect on the health of swine facility workers. The investigated pig building was found to be a source of chemical pollutants as well as biological agents. The total bacterial count in 1 m3 of air was 3.6×106 and 4.6×106 cfu, during the winter and summer periods of fattening, respectively. Gram-positive cocci predominated in both seasons. In the winter, fungi of the Trichoderma genus were represented equally often. In the summer period, up to 90% of the isolated fungus was Aspergillus spp. Conclusions. Workers engaged in swine rearing and production are occupationally exposed not only to a high concentration of microbial contamination, but also to irritating and odorogenous volatile compounds. Thus, activities directed at the promotion of health prevention strategies, as well as effective guidelines for safe and hygienic animal housing, should be implemented

Condition of mineralized tooth tissue in a population of 15-year-old adolescents living in a region of Ukraine with slightly exceeded fluorine concentration in the water

Introduction. Fluorine is a common element in nature; however, the difference between a beneficial dose and a toxic dose for the organisms is small. The main source of fluoride for humans is water in addition to food. Objective. The aim of this study was to estimate the degree of severity of pathological changes, namely, caries or fluorosis, in the mineralized tooth tissue of 15-year-old adolescents with respect to their hygienic and nutritional habits, and the content of fluorine in drinking water, soil and plant products. Materials and method. 100 adolescents aged 15 from schools in Sosniłka, L’viv region, were examined. The condition of mineralized tooth tissue was evaluated by the caries severity, expressed by the mean number D3MFT, caries frequency and value of the SIC index. Fluorine in plant material and soil were determined according to the PN-G-04543:1982 standard, and water according to the PN-EN ISO 10304 – 1: 2009+ AC: 2012 standard. Results. Severity of caries disease expressed by the D3MFT number in the examined group of 15-year-olds was 3.39; in the group of girls – 3.08, and in the group of boys – 3.76. In the examined group, the average number of teeth with fluorosis was 7.59. Value of the SIC index among the examined population of students (n-31) was 6.26: 5.89 (n-18) for girls and 7.31 (n-13) for boys. Fluorine concentration in the water was 0.78 – 1.25(mg·dm-3). In the soil, it also did not vary across the sampled areas and amounted, on average, to 176 mg·dm-3. The biggest fluorine content noted in the dry mass of beetroots was 3.50 (mg F· kg), and the lowest – 3.34 (mg F· kg). Conclusions. Close to optimal fluorine content lowers caries severity and frequency of fluorosis. Optimal fluorine content in drinking water and food does not require additional diet supplementatio