Children’s residential exposure to selected allergens and microbial indicators: endotoxins and (1→3)-β-D-glucans

Objectives: The study was aimed at assessment of exposure to endotoxins, (1→3)-β-D-glucans and mite, cockroach, cat, dog allergens present in settled dust in premises of children as agents which may be significantly correlated with the occurrence of allergic symptoms and diseases in children. Materials and Methods: The study covered 50 homes of one- or two-year-old children in Poland. Samples of settled dust were taken from the floor and the child's bed. The levels of (1→3)-β-D-glucans (floor), endotoxins (floor) and allergens of mite, cat, dog and cockroach (floor and bed) were analyzed. Results: Average geometric concentrations (geometric standard deviation) of endotoxins, (1→3)-β-D-glucans, Der p1, Fel d1, Can f1 and Bla g1 in children homes were on the floor 42 166.0 EU/g (3.2), 20 478.4 ng/g (2.38), 93.9 ng/g (6.58), 119.8 ng/g (13.0), 288.9 ng/g (3.4), 0.72 U/g (4.4) and in their beds (only allergens) 597.8 ng/g (14.2), 54.1 ng/g (4.4), 158.6 ng/g (3.1) 0.6 U/g (2.9), respectively. When the floor was covered with the carpet, higher concentrations of endotoxins, (1→3)-β-D-glucans and allergens (each type) were found in the settled dust (p < 0.05). The trend was opposite in case of allergens (except dog) analyzed from bed dust and significantly higher concentrations were found in the rooms with smooth floor (p < 0.05). Conclusions: Among the analyzed factors only the type of floor significantly modified both the level of biological indicators and allergens. The results of this study could be the base for verifying a hypothesis that carpeting may have a protective role against high levels of cockroach, dog and cat allergens

Visible fungi growth and dampness assessed using a questionnaire versus airborne fungi, (1→3)-β-d-glucan and fungal spore concentrations in flats

Introduction The study aimed at determination of the usefulness of the subjective assessment of selected signs of fungi growth in flats and microclimate parameters to indicate the actual air contamination with culturable fungi, (1→3)-β-D-glucans and fungal spores. Material and methods This analysis covered 22 flats, the inhabitants of which declared in a questionnaire interview the presence of the developed mycelium on solid surfaces in the flat. Air samples for determination of the culturable fungi, (1→3)-β-D-glucans and (viable and non-viable) fungal spores concentrations indoor and outdoor the flats during the heating period were collected. During bioaerosol sampling microclimate parameters were measured. Predictive models for concentrations of the tested biological agents with regard to various ways to assess fungal contamination of air in a flat (on the basis of a questionnaire or a questionnaire and microclimate measurements) were built. Results The arithmetic means of temperature, relative humidity, CO2 concentration and air flow velocity in the flats were respectively: 20.5°C, 53%, 1431.6 ppm and 0 m/s. The geometric mean concentrations of airborne fungi, (1→3)-β-D-glucans and fungal spores in these premises amounted to 2.9×102 cfu/m3, 1.6 ng/m3 and 5.7×103 spores/m3, respectively. The subjective assessment of fungi growth signs and microclimate characteristics were moderately useful for evaluation of the actual airborne fungi and (1→3)-β-D-glucan concentrations (maximum percent of explained variance (VE) = 61% and 67%, respectively), and less useful in evaluation of the actual fungal spore concentrations (VE < 29%). In the case of fungi, higher usefulness was indicated of the questionnaire evaluation supported by microclimate measurements (VE = 61.2%), as compared to the evaluation only by means of a questionnaire (VE = 46.9%). Conclusions Subjective evaluation of fungi growth signs in flats, separately or combined with microclimate measurements, appeared to be moderately useful for quantitative evaluation of the actual air contamination with fungi and their derivatives, but more extensive studies are needed to strengthen those findings

Assessment of exposure to fungi in the heavily contaminated work environment (a solid waste sorting plant) based on the ergosterol analysis

Objectives: This paper reports on the results of the study aimed at application of ergosterol as an quantitative indicator of fungal bioaerosol present in the indoor air in occupational environment heavily contaminated with organic dust as well as its comparison with the culturable method. Material and Methods: The study was conducted in the indoor solid waste sorting plant. Using Andersen impactor adapted to 1 plate at the flow rate of 30 l/min, indoor air was sampled in the workers’ breathing zone. Ergosterol was sampled using gelatinous filter (1000 l of air) and then analyzed by means of the spectrophotometric method. Fungi were sampled on malt extract agar (MEA) medium (3 replications: 2 l, 7.5 l, 15 l of air) and analyzed by means of the culturable method. Based on ergosterol analyzes, concentration of fungi was calculated. Results were given as the range assuming min. as 5.1 pg ergosterol/spore and max as 1.7 pg ergosterol/spore. Results: The average concentrations of ergosterol in a working room (arithmetic mean (AM), standard deviation (SD); minimum–maximum (min.–max)) were, respectively: 2.16, 0.72; 0.85–2.92 μg/m3; fungi calculated based on ergosterol – 424.1×103–1272.4×103, 140.1×103– 420.4×103, 167×103–1716.5×103 CFU/m3, and culturable fungi – 13×103, 9.7×103, 1.9×103–34×103 CFU/m3). It was revealed that concentrations of calculated fungi were even 2 orders of magnitude higher than culturable fungi. Conclusions: The quantitative assessment of moldiness by means of ergosterol measurement seems to be a reliable indicator for environments heavily contaminated with organic dust, where viable and non-viable fungi are present in high proportions. Based on that result, more restrictive (as compared to a similar assessment carried out by means of the culturable method) hygienic recommendations, especially those related to the use of preventive measures protecting the employees’ respiratory tract, should have been undertaken

The capability of fungi isolated from moldy dwellings to produce toxins

Objectives: The main objective was analysis and assessment of toxinogenic capabilities of fungi isolated from moldy surfaces in residential rooms in an urban agglomeration situated far from flooded areas in moderate climate zone. Material and Methods: The assessment of environmental exposure to mycotoxins was carried out in samples collected from moldy surfaces in form of scrapings and airborne dust from 22 moldy dwellings in winter season. In each sample 2 mycotoxins were analyzed: sterigmatocystin and roquefortine C produced by Aspergillus versicolor and Penicillium chrysogenum, respectively. Mycotoxins were analyzed by high-performance liquid chromatography (HPLC) in: scrapings from moldy surfaces, mixture of all species of fungi cultured from scrapings on microbiological medium (malt extract agar), pure cultures of Aspergillus versicolor and Penicillium chrysogenum cultured from scrapings on microbiological medium; mycotoxins in the indoor air dust were also analyzed. Results: The production of sterigmatocystin by individual strains of Aspergillus versicolor cultured on medium was confirmed for 8 of 13 isolated strains ranging 2.1–235.9 μg/g and production of roquefortine C by Penicillium chrysogenum for 4 of 10 strains ranging 12.9–27.6 μg/g. In 11 of 13 samples of the mixture of fungi cultured from scrapings, in which Aspergillus versicolor was found, sterigmatocystin production was at the level of 3.1–1683.2 μg/g, whereas in 3 of 10 samples in which Penicillium chrysogenum occurred, the production of roquefortine C was 0.9–618.9 μg/g. The analysis did not show in any of the tested air dust and scrapings samples the presence of analyzed mycotoxins in the amount exceeding the determination limit. Conclusions: The capability of synthesis of sterigmatocystin by Aspergillus versicolor and roquefortine C by Penicillium chrysogenum growing in mixtures of fungi from scrapings and pure cultures in laboratory conditions was confirmed. The absence of mycotoxins in scrapings and air dust samples indicates an insignificant inhalatory exposure to mycotoxins among inhabitants in moldy flats of urban agglomeration situated far from flooded territories. Int J Occup Med Environ Health 2016;29(5):823–83

Children’s residential exposure to selected allergens and microbial indicators: endotoxins and (1→3)-β-D-glucans

Objectives: The study was aimed at assessment of exposure to endotoxins, (1→3)-β-D-glucans and mite, cockroach, cat, dog allergens present in settled dust in premises of children as agents which may be significantly correlated with the occurrence of allergic symptoms and diseases in children. Materials and Methods: The study covered 50 homes of one- or two-year-old children in Poland. Samples of settled dust were taken from the floor and the child's bed. The levels of (1→3)-β-D-glucans (floor), endotoxins (floor) and allergens of mite, cat, dog and cockroach (floor and bed) were analyzed. Results: Average geometric concentrations (geometric standard deviation) of endotoxins, (1→3)-β-D-glucans, Der p1, Fel d1, Can f1 and Bla g1 in children homes were on the floor 42 166.0 EU/g (3.2), 20 478.4 ng/g (2.38), 93.9 ng/g (6.58), 119.8 ng/g (13.0), 288.9 ng/g (3.4), 0.72 U/g (4.4) and in their beds (only allergens) 597.8 ng/g (14.2), 54.1 ng/g (4.4), 158.6 ng/g (3.1) 0.6 U/g (2.9), respectively. When the floor was covered with the carpet, higher concentrations of endotoxins, (1→3)-β-D-glucans and allergens (each type) were found in the settled dust (p < 0.05). The trend was opposite in case of allergens (except dog) analyzed from bed dust and significantly higher concentrations were found in the rooms with smooth floor (p < 0.05). Conclusions: Among the analyzed factors only the type of floor significantly modified both the level of biological indicators and allergens. The results of this study could be the base for verifying a hypothesis that carpeting may have a protective role against high levels of cockroach, dog and cat allergens