High-volume evacuation mitigates viral aerosol spread in dental procedures.

Dental healthcare personnel (DHCP) are subjected to microbe-containing aerosols and splatters in their everyday work. Safer work conditions must be developed to ensure the functioning of the healthcare system. By simulating dental procedures, we aimed to compare the virus-containing aerosol generation of four common dental instruments, and high-volume evacuation (HVE) in their mitigation.

Cryptosporidium parvum: an emerging occupational zoonosis in Finland.

Background: Cryptosporidiosis has increased in recent years in Finland. We aimed to identify risk factors for human cryptosporidiosis and to determine the significance of Cryptosporidium parvum as a causative agent. Based on notifications to the Finnish Infectious Disease Register (FIDR), we conducted a case-control study and genotyped Cryptosporidium species from patient samples from July to December 2019.

Safe use of PHI6 IN the experimental studies.

Surrogate viruses theoretically provide an opportunity to study the viral spread in an indoor environment, a highly needed understanding during the pandemic, in a safe manner to humans and the environment. However, the safety of surrogate viruses for humans as an aerosol at high concentrations has not been established. In this study, Phi6 surrogate was aerosolized at high concentration (Particulate matter: ∼1018 μg m) in the studied indoor space.

Exposure to bacterial and fungal bioaerosols in facilities processing biodegradable waste.

The aim of the study was to determine the exposure of workers within biodegradable waste processing facilities to bacteria and fungi to identify any exposures of potential concern to health. Occupational measurements were performed in six composting and three bioenergy (bioethanol or methane/biogas) producing facilities. Bioaerosols were measured from breathing zones with Button aerosol or open face cassette filter samplers, and swab specimens were taken from the nasal mucous membranes of the workers.

Combining Phi6 as a surrogate virus and computational large-eddy simulations to study airborne transmission of SARS-CoV-2 in a restaurant.

COVID-19 has highlighted the need for indoor risk-reduction strategies. Our aim is to provide information about the virus dispersion and attempts to reduce the infection risk. Indoor transmission was studied simulating a dining situation in a restaurant.

Large-scale decontamination of disposable FFP2 and FFP3 respirators by hydrogen peroxide vapour, Finland, April to June 2020.

BackgroundThe shortage of FFP2 and FFP3 respirators posed a serious threat to the operation of the healthcare system at the onset of the COVID-19 pandemic.AimOur aim was to develop and validate a large-scale facility that uses hydrogen peroxide vapour for the decontamination of used respirators.MethodsA multidisciplinary and multisectoral ad hoc group of experts representing various organisations was assembled to implement the collection and transport of used FFP2 and FFP3 respirators from hospitals covering 86% of the Finnish population.

Review of biological risks associated with the collection of municipal wastes.

In many countries, the management of household waste has recently changed with an increased focus upon waste sorting resulting in lower collection frequency for some waste fractions. A consequence of this is the potential for increased growth of microorganisms in the waste before collection, which can lead to an increased exposure via inhalation for waste collection workers. Through a review of the literature, we aimed to evaluate risks caused by waste collecting workers' exposure to bioaerosols and to illuminate potential measures to reduce the exposure.

Peak exposures to main components of ash and gaseous diesel exhausts in closed and open ash loading stations at biomass-fuelled power plants.

Fly and bottom ashes are collected at power plants to reduce the environmental effects of energy production. However, handling the ashes causes health problems for operators, maintenance workers and truck drivers at the power plants. Hence, we evaluated ash loaders' peak inhalation exposures to the chemical components of ash and diesel exhausts in open and closed ash loading stations at biomass-fuelled combined heat and power plants.

The occupant as a source of house dust bacteria.

Background: Markers for microbial groups are commonly measured in house dust samples to assess indoor exposure to microbes in studies on asthma and allergy. However, little is known about the sources of different microbes. A better understanding of the nature and origin of microbes present in the immediate environment of human beings is crucial if one wants to elucidate protective as well as adverse effects on human health.

Predominance of Gram-positive bacteria in house dust in the low-allergy risk Russian Karelia.

Simple living conditions and farming environment have been associated with reduced risk for allergic diseases such as atopy and asthma but the factors responsible for this effect remain unresolved. We examined the bacterial composition of house dusts obtained from Finnish and Russian Karelia, two adjacent areas with high and low occurrence of atopic diseases respectively. Two dust mixes, both composed of 10 randomly selected dust samples from 349 Finnish and 417 Russian Karelian households were studied for bacterial biomarkers (DNA, Limulus-active endotoxin, 3-OH fatty acids, muramic acid) and for 16S rRNA gene sequences.

Variety in dustiness and hygiene quality of peat bedding.

Respiratory exposure to organic dust induces chronic pulmonary diseases both in farmers and horses. The aim of this study was to examine the variation of dustiness and hygiene quality of peat moss bedding. Materials studied were weakly decomposed sphagnum peat (A), weakly decomposed sphagnum peat warmed up in storage (> 30 degrees C) (B) and two more decomposed few-flowered sedge peats (C and D).

Microbial exposure and mold-specific serum IgG levels among children with respiratory symptoms in 2 school buildings.

In this study, the authors determined the association between serum mold-specific immunoglobulin G (IgG) levels in primary school children (N = 181) with asthma, wheezing, or cough symptoms and exposure to indoor mold in 2 schools, with and without mold damage. Microbial exposure was determined with environmental sampling. Serum IgG antibody concentrations against 24 microbial strains were determined with enzyme-linked immunosorbent assay.

Mold-specific immunoglobulin G antibodies in a child population.

The determination of immunoglobulin G (IgG) antibodies to molds has been used as an objective evidence of significant mold exposure. Until present, no data have been published on antibody responses to molds in healthy children living in normal housing conditions. The microbe-specific IgG antibody concentrations of 21 molds and 3 actinobacteria were determined by enzyme-linked immunosorbent assay (ELISA) in 103 1- to 6-year-old children (12.

Control of workers' exposure to airborne endotoxins and formaldehyde during the use of metalworking fluids.

The study evaluated the effects of triazine use and machine enclosure on workers' exposure to bacteria, endotoxins, and formaldehyde in the use of metalworking fluids (MWF). Concentrations of triazine and bacterial contaminants were monitored in bulk samples of MWF from two machines in one workplace. One of the machines was used normally; triazine was added to the other when needed.

Mould-specific immunoglobulin G antibodies in students from moisture- and mould-damaged schools: a 3-year follow-up study.

Immunoglobulin G (IgG) antibodies to moulds have been used as biomarkers of mould exposure, though their role reflecting exposure is not confirmed. The purpose of the present study was to evaluate the changes in mould-specific IgG antibodies in children during a 3-year follow-up in relation to changes in exposure, and to allergic and respiratory morbidity. In 1996, 212 primary school students with asthma, wheezing or prolonged cough participated in a clinical study, including clinical examination, skin-prick tests to 12 moulds and mould-specific IgG determinations to 24 moulds.

Importance of sampling, extraction and preservation for the quantitation of biologically active endoto.

The influence of filter media, extraction solution and preservation method on detection of biologically active endotoxin in the LAL assay was studied with air samples collected from wastewater treatment plants. The four most common types of filters were used as collection media. The extraction solutions compared were nonpyrogenic water, KH2PO4-triethylamine and Trizma buffers.