All employers are responsible for ensuring safe working conditions for employees in their workplace.
It is necessary to accurately identify and eliminate all hazards that are possible to remove and to ensure proper collective and personal protective measures. Among occupational hazards, biological agents are one of the most important. They are considered as the most frequent cause of occupational diseases in Poland. They can affect human body and cause various adverse health outcomes such as allergies, irritations, infections, toxicoses or
even a cancer. Among them we can distinguish harmful microorganisms (bacteria, viruses, fungi),
human parasites and biologically active chemical compounds produced by microorganisms (e.g., fungal mycotoxins). Currently, the most frequent used laboratory procedures to identify biological hazards are culture-based, microscopic and biochemical methods. Despite their unquestionable advantages and widespread presence, these techniques have also important limitations. They only enable identification of microorganisms which are
viable and capable to grow in laboratory conditions.
As the studies have shown, such microorganisms constitute (in extreme cases) merely 1% of
their population present in the environment. This paper presents an overview of molecular biology methods (based on DNA analysis) which allow the qualitative and quantitative identification of microorganisms,
determining their biochemical features and enabling to obtain their environmental species profile without the need for their culturing in laboratory conditions. Application of these methods provides more accurate identification of microorganisms present in occupational environment, allowing more precise analysis of potential health
risks derived from exposure to harmful biological agents.

Wood is a raw material of the wood industry, which is used as a solid wood or in a processed form. Occupational exposure to wood dust occurs during processing and woodworking. The highest levels of wood dust concentrations in the working environment were recorded in the furniture and carpentry industries.
The number of workers exposed to wood dust in Poland estimated during WOODEX project (2000-2003) amounted to 310 000, of which 79 000 workers were exposed to wood dust at concentrations <0.5 mg/m3, 52 000 workers at concentrations 0.5–1 mg/m3, 63 000 workers at concentrations 1–2 mg/m3, 72 000 workers at concentrations 2–5 mg/m3 and 44 000 workers at concentrations According to data from selected sectors of the economy
in Poland in years 2001–2005 developed in collaboration with the Chief Sanitary Inspectorate at the Institute of Occupational Medicine in Łódź, the arithmetic mean value of inhaled wood dust concentration in the wood production and wood products sector (excluding furniture) was 2.08 mg/m3.
This concentration was calculated on the basis of 8602 measurements. In the case of hardwood dust,
exceeded values of NDS at worksites were reported in more than 20% of the measurements,
whereas in case of softwood – in less than 10% of measurements.
Exposure to dust from deciduous trees (hardwood, mainly oak and beech wood) or from a mixture with coniferous species (softwood) is correlated with nasopharyngeal adenocarcinomas, whereas non-neoplastic respiratory symptoms, excluding asthma, are not correlated with a specific type of wood. Occupational asthma is most often the result of action of the biologically active compounds present in some wood species (both hardwood and
softwood). One of the better-known species of wood and source of knowledge about occupational
asthma is the dust of red cedar wood.
Hardwood and softwood dusts may impair clear airway, resulting in chronic lung disease. The health effects of exposure to wood dust concern the upper or lower respiratory tract depending on the size of wood particles. Occupational exposure to wood dust causes: chronic bronchitis, rhinitis and conjunctivitis, skin irritation and allergic skin reactions.
Spirometry has shown the reduction of the lung function index as a result of mechanical or chemical irritation of lung tissue. It should be noted that changes in pulmonary function and the occurrence of occupational asthma
was found in the wood industry workers, mainly employed in furniture industry (with no history of atopy) at concentrations below 1 mg/m3 of wood dust.
A review of the studies in humans and in experimental animals shows that wood dust has mutagenic and genotoxic effects. Analysis of DNA taken from people with cancer of the paranasal sinuses and exposed to wood dust showed mutations, mainly in gene k-ras, which is one of the most frequently activated oncogenes in human cancers. Furthermore, h-ras mutations in adenocarcinoma patients, chromosomal aberrations in carpenter
peripheral blood lymphocytes, damage to DNA strands in rats hepatocytes, increase in micronuclear frequency in cells of mouse intestine and rats nasal epithelium have been found.
The relationship between the incidence of a nose and paranasal sinuses cancer and the exposure to wood dust was proved on the basis of results of epidemiological studies. The risk of adenocarcinoma was significantly higher as compared to the risk of squamous cell carcinoma.
The International Agency for Research on Cancer concluded that there was sufficient evidence of carcinogenicity
of wood dust in humans and assigned it to Group 1 – a substances with proven carcinogenic effects in humans.
The Commission of the European Union included research on exposure to hard and mixed wood dust to technological processes classified as carcinogenic to humans (Directive 2004/37 / EC) and established
BOELV value for inhalable wood dust fraction on a level of 5 mg/m3 indicating that if there is a mixture of hardwood dust with other wood dust then NDS refers to the total wood dust present in the mixture.
SCOEL Scientific Committee resigned from the division into hardwood and softwood and proposed the exposure limit value for wood dust, taking into account not only its irritating effects on upper and lower respiratory tract but also carcinogenicity (inhalable fraction: 1 mg/m3, total dust 0.5 mg/m3). The health effects of exposure to wood dust and the socio-economic conditions have also been considered by the Committee on Safety and Health at Work
(ACSHW), which has proposed BOELV value for hardwood dusts of 3 mg/m3, taking into account that
the lower value would result in the closure of many companies, mostly small, employing from 1 to 9 employees.
Establishment of the hygienic standards of wood dust is complicated by the fact that we are never exposed to the wood itself. At the same time, we are exposed to naturally occurring chemicals in wood (most of them are irritating and sensitizing).
Moreover, biological fraction (bacteria, mold) found in wood dust, mainly fresh, as well as wood preservatives such as organic solvents or formaldehyde, increase the health risk.
Another variable considered when assessing risk associated with exposure to wood dust is the particle size emitted during wood processing, which varies according to the type of wood and its treatment.
Aerodynamic diameter of the particles is generally in the range of 10 to 30 m, which classifies them into an extra thoracic fraction (penetrating head area) or thoracic fraction (penetrating the trachea bronchial area). Percentage of respirable fraction is usually 15–20%.
When setting the NDS value for wood dusts, data from a cross-sectional survey of 161 people employed in wood dust exposure in 54 furniture companies were used. Nasal patency was examined after exposure to mixed wood dust at a low concentration (0.17–0.74 mg/m3), mean (0.74–1.42 mg/m3) and high (1.42 mg/m3). With regard
to nasal patency before commencement of the work, exposure to medium and high concentration of wood dust significantly increased nasal congestion, reduced nasal cavity capacity and reduced nasal cross-sectional area as a result of 4–7 hours of exposure. There was a statistically significant relationship between the concentration of wood dust and nasal obstruction grade determined by the method of acoustic rhinometry and subjective
assessment. These symptoms also occurred when dust concentrations were small, but these symptoms
were not statistically significant. Furthermore, patients in the control group had significant differences in nasal passivity before commencement of work compared to the post-work period, thus undermining the observed changes at low concentrations (0.17–0.74 mg/m3) of wood dust.
Taking into account the above data as well as socioeconomic factors discussed with wood industry representatives in Poland, the Interdepartmental Commission on NDS and NDN at its 84th meeting on November 4, 2016, adopted a concentration of 3 mg/m3 for the maximum permissible concentration (NDS) for the inhalable fraction of all wood
dust. Socioeconomic considerations were also taken into account in determining BOELV value for the inhalable wood dust fraction (3 mg/m3) in the European Union. The adoption of this value without distinction for hardwood and softwood is a compromise between current NDS values for wood dust with the exception of oak and beech
dusts (4 mg/m3) and beech and oak dust (2 mg/m3).
The proposed value of NDS is at the level proposed by the European Commission for BOELV for the hardwood dust inhalable fraction (3 mg/m3), which takes into account socio-economic conditions of companies. Due to the fact that wood dusts are carcinogenic, mutagenic and cause pneumoconiosis,
the determination of NDSCh values is unjustified.
It is proposed to mark the wood dust with notation "Carc. 1”– category 1 carcinogen, according to the classification of the International Agency for Research on Cancer, and with letter “A” because of possible sensitization.

The term "flour dust" refers to particles derived from finely milled ground cereal grains and noncereal grains. Flour dust usually contains components which play an important role in dough improvement, such as enzymes, baker's yeast, flavors, spices and chemical ingredients such as preservatives. Flour is one of the basic raw materials used in the food industry and in animal feed production. Taking into account the nature of the production activities in mentioned industries, the highest occupational exposure to flour dust is usually observed in bakeries and grain mills. A significant exposure to flour dust occurs also in pasta factories, pizza and pastry bakeries, restaurant kitchens, malt factories, animal feed factories and in agriculture.
The main route of exposure to flour dust in occupational conditions is respiratory and skin.
The main effect of repeated or long-lasting hu-man exposure to flour dust is irritation and allergy.
Epidemiological reports have shown that asthma, conjunctivitis, rhinitis and skin reactions are the main adverse health effects of flour dust exposure.
In Poland, the maximum admissible value (MAC, NDS) for flour dust is the same as for organic dust (plant and animal origin). The MAC values are: for inhalable fraction 2 mg/m3 and for respirable fraction 1 mg/m3 when dust contains 10% or more crystalline silica and when dust contains less than 10% of crystalline silica, 4 mg/m3 for inhalable fraction and 2 mg/m3 for respirable fraction. The need to prepare documentation for flour dust resulted from the fact that existing documentation and MAC values mainly concern the effects of farmers' exposure to organic dust of plant and animal origin. It did not refer to flour dust for which the sensitization effect is critical.
The basic mechanism of action of the flour dust on the body is the reaction of hypersensitivity with stimulation of antibodies type E (IgE) developing shortly after exposure to an antigen.
The value of hygienic norms for flour dust in Poland has not been established yet.
There is no data regarding animal experiments and in vitro studies with flour dust. On the basis of epidemiological studies, the risk of nasal symptoms has been found to increase with dust concentrations of 1 mg/m3 and the risk of asthma at concentrations above 3 mg/m3.
The SCOEL assumes that exposure to the inhalable fraction of flour at a concentration of ≤1 mg/m3 protects most exposed workers from nasal mucositis and that the predicted symptoms, if present, are mild. However, the concentration of flour dust
<1 mg/m3 may cause symptoms in already sensitized workers. The results of the study show that the full protection against allergens present in the flour dust in the air at low concentrations is difficult to achieve. At the same time, ACGIH's recommended TLV value for the inhalable flour dust fraction at 0.5 mg/m3 (8 h TWA). The "dose-response" results suggest that the symptoms of exposure to flour, especially from the lower res-piratory tract, asthma, as well as the risk of sensi-tization, are rare in the inhalable fraction concen-tration in the range 0.5 – 1 mg/m3.
Considering the above, the Interdepartmental Commission for MAC and MAI at the 84th meet-ing (November 4, 2016) adopted the TLV value for the inhalable fraction of flour dust at the level of
2 mg/m3, that is, at the level of the current MAC value for inhalable fraction of dust containing >10% of the crystalline silica. No grounds for determining the short-term limit MAC (STEL) and the limit value in biological material. The standard is marked with "A" (sensitizing substance).

Cyclophosphamide (CP) at room temperature is a fine white crystalline odorless powder. It is used mainly as a cytostatic drug in anticancer therapy. Acute exposure to CP can cause bone marrow damage, hemorrhagic cystitis and cardiomyopathy.
Cyclophosphamide has a negative influence on reproducibility in humans. International Agency for Research on Cancer (IARC) has classified CP as carcinogenic to humans (Group 1). In the Eu-ropean Union, cyclophosphamide has been classified as carcinogenic category 1.A and mutagenic category 2.B. Occupational exposure to CP may occur during its production and during preparation and application of CP in oncology wards. Cyclophosphamide may be absorbed mainly by inhalation or skin contact.
The aim of this study was to develop and vali-date a sensitive method for determining cyclophosphamide concentrations in workplace air in the range from 1/10 to 2 MAC values, in accord-ance with the requirements of Standard No. PN-EN 482.
The study was performed using a liquid chro-matograph with a tandem mass detection (HPLC-MS/MS). All chromatographic analyses were performed with Supelcosil LC 18 150 × 3 mm analytical column, which was eluted with a mix-ture of methanol and water with 0.1% of formic acid.
The method was based on collecting CP on glass fiber filter, extracting with a mixture of methanol: water with addition of formic acid (0.1%), and chromatographic determining of resulted solution with HPLC-MS/MS technique. The average extraction efficiency of CP from filters was 90%. The method was linear (r = 0.999) within the in-vestigated working range 0.01 – 0.5 μg/ml. The calculated limit of detection (LOD) and the limit of quantification (LOQ) were  0.00046 and 0.0015 μg/ml, respectively.
The analytical method described in this paper, thanks to HPLC-MS/MS technique, enables specific and selective determination of CP in work-place air in the presence of other compounds
at concentrations from 0.0004 mg/m3 (1/25 proposed MAC value). The method precise, accurate and it meets the criteria for measuring chemical agents listed in Standard No. PN-EN 482. The method can be used for assessing occupational exposure to CP and associated risk to workers’ health. The developed method of determining CP has been recorded as an analytical procedure (see appendix).

2,2-Bis(4-hydroxyphenyl)propane (bisphenol A BPA) is a substance in a form of a solid crystals or flakes with a mild phenolic odor. BPA is commonly used in the production of epoxide, poly-carbonate or polysulfone resins, glues, breaks fluids or as
a flame retardants and fungicides. Exposure to BPA can cause irritation of skin, BPA can also act as a nefro or hepatotoxic factor and upper respir-atory tract or mucous membranes of the eye. BPA has a negative effects on human fertility.
The aim of this study was to develop and validate a sensitive method for determining BPA concentrations in workplace air in the range from 1/10 to
2 MAC values, in accordance with the requirements of Standard No. PN-EN 482.
The study was performed using a liquid chromatograph with spectrophotometric (UV-VIS) and spectrofluorimetric (FLD) detection. All chromatographic analyses were performed with Supelcosil LC 18 (150 × 3 mm) analytical column, which was eluted with mixture of acetonitrile and water (1: 1).
This method was based on collecting BPA on glass fiber filter, extracting with acetonitrile, and chromatographic determining resulted solution with HPLC technique. The average extraction efficiency of BPA from filters was 90%. The meth-od was linear (r = 0.9996) within the investigated working range 0.125 – 5 mg/m3 for a 720-L air sample. The calculated limit of detection (LOD) and the limit of quantification (LOQ) was to 0.02 μg/ml (UV-VIS) and 0.013 μg/ml (FLD), and 0.068 μg/ml (UV-VIS) and 0.042 μg/ml (FLD), respectively.
The analytical method described in this paper enables specific and selective determination of BPA in workplace air in presence of other com-pounds. The method is precise, accurate and it meets the criteria for measuring chemical agents listed in Standard No. PN-EN 482+A1:2016-01. The method can be used for assessing occupational exposure to BPA and associated risk to workers’ health. The developed method of determining BPA has been recorded as an analytical procedure (see appendix).

Lithium hydride is a solid, unstable substance. It reacts violently with water to produce strong liquor (LiOH) and hydrogen. It may selfignite. It is used in metallurgical, pharmaceutical, ceramic and chemical industries.
Lithium hydride is strongly toxic. It is irritating and corrosive to skin, it can damage mucous membranes of the respiratory tract. May cause eye burns and loss of vision. Lithium hydride is harmful to the digestive tract, nervous system and kidneys. The exposure limit value for lithium hydride is NDS – 0.025 mg/m3.
The aim of this study was to amend the method for determining concentrations of lithium hy--dride in workplace air in the range from 1/10 to 2 NDS values, in accordance with the requirements of Standard No. EN 482.
The developed method is based on the collection of lithium hydride contained in the air on a membrane filter, mineralization of the filter using concentrated nitric acid, and determination of lithium in a solution prepared for analysis with atomic absorption spectrometry with lean flame atomization air-acetylene (F-AAS).
This method enables determination of lithium in
a concentration range of 0.05 - 3.50 g/ml. The
obtained lithium calibration curve is character-ized by a high correlation coefficient (R2 = 1.0000). The detection limit of lithium (LOD) is 1 ng/ ml, and the limit of quantification (LOQ) is 4 ng/ ml.
Determined coefficient of recovery is 1.00.
The developed method enables determination of lithium hydride in workplace air in the concen-tration range of 0.0008 - 0.056 mg/m3 (for a 720-L air sample) which represents 0.03 - 2.24 NDS.
The method of determining lithium hydride has been recorded as an analytical procedure (appendix).