Fundamentals of General and Pharmaceutical Hygiene - Dykyi I.L. 2003

Hygiene of the Air Environment
Air dust pollution. Determination of dust concentration and dispersity in the air of industrial premises

Atmospheric air and indoor air always contain a certain amount of dust. The air in the production areas of pharmacies and pharmaceutical plants can be contaminated with dust from medicinal substances released during weighing, sifting, tableting, transportation, and other technological operations. Dust is also generated during the packaging of medicinal plant Materials and the preparation of herbal mixtures.

Industrial dust is classified according to its origin, formation mechanism, chemical properties, dispersity, and biological activity.

Monitoring dust pollution in industrial indoor air is of major hygienic importance, as dust can exert general toxic, Skin-resorptive, irritant, and allergenic effects on the body, and may cause Pneumoconiosis, Bronchitis, skin and mucous membrane diseases, and tumors.

Hygienic assessment of dust pollution involves determining: 1) the quantity and 2) the dispersity of dust.

Objective: to learn how to determine the amount and dispersity of dust in the working zone air, provide a hygienic Assessment of the obtained data, and develop measures to reduce dust pollution levels in the air of pharmacy and pharmaceutical manufacturing facilities.

QUESTIONS FOR SELF-ASSESSMENT

1. Classification and properties of industrial dust.

2. What effects does dust have on The Human Body?

3. What factors influence the biological effect of dust?

4. Classification of pneumoconioses.

5. What is the specific nature of The Effect of medicinal dust on the body?

6. Prevention of dust-related occupational diseases.

7. Determination of dust concentration in the air.

8. Determination of dust dispersity.

Task 1. Determination of dust concentration in the air

The main METHOD FOR DETERMINING dust concentration in the air is the gravimetric (weight) method. It is based on drawing a test air sample through filters that trap dust particles, thereby increasing their weight. The amount of dust particles in the air is determined by the difference in the filter mass before and after sampling. Currently, aerosol analytical filters (AFA) made of FPP fabric (Petryanov perchlorovinyl filter) are used.

The analytical filter assembly is removed by its tab from the storage cassette. The pouch is opened, the protective rings are unfolded, and using tweezers, the filter is folded into quarters and placed in the center of the analytical balance pan, making sure it does not hang over the edges. The filter is weighed with an accuracy of 0,1 mg, after which it is placed back into the protective rings by carefully straightening its pressed edges, and then returned to the pouch and cassette. At the sampling site, the filters are removed from the cassette and pouch, and inserted into a holder connected to an electric aspirator. Using the air-flow rate regulator located on the aspirator's rotameter, the air movement speed is set within 15-20 L/min. The sampling duration depends on the dustiness level of the air (typically no more than 30 min).

After air sampling, the filter is removed from the holder by its tab, folded in half with the trapped deposit inward, and placed in the pouch. Re-weighing is performed as described above, after conditioning the filters at initial Temperature and humidity conditions for 10-15 min.

The dust concentration in the air is determined by the formula

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where X is the amount of dust per 1m³ of air, mg;

a is the mass of the filter after air sampling (mg);

b is the mass of the filter before air sampling (mg);

1000 is the conversion factor for air volume from liters to m³;

V_o is the volume of the test air sample reduced to normal conditions (Topic 2, see the formula for reducing air volume to normal conditions using the aspiration sampling method).

The obtained result is compared with the MPC for this substance or preparation (see Table 5 in the Appendix).

Task 2. Determination of dust dispersity

To determine dust dispersity, a microscopic examination of the dust sample is performed. For this purpose, the filter remaining after the quantitative dust determination is placed dust-side down on a Microscope slide, which is then placed in a Glass vessel with preheated acetone. The filter fabric quickly becomes transparent and is fixed as a thin transparent layer on the glass surface.

In cases where dust particles are soluble in organic Solvents, the dust sample is prepared by natural sedimentation of dust particles onto horizontally or vertically positioned glass coated with any adhesive substance (glycerin, petroleum jelly, a 2% solution of Canada balsam in xylene).

The resulting dust sample is examined under a microscope at high magnification (or using immersion) with the help of a micrometer eyepiece inserted into the microscope eyepiece. The micrometer eyepiece is a scale engraved on a circular glass plate with divisions from 0 to 50. The value of one scale division is pre-calibrated using a stage micrometer, which has a division value of 10 µm. To do this, the lines of both scales—the micrometer eyepiece and the stage micrometer—are aligned, the number of eyepiece divisions that fit until they coincide with the stage micrometer lines is counted, and the value of a single division is determined.

Example. 20 Divisions of the micrometer eyepiece scale fit within 6 divisions of the stage micrometer. Therefore, the value of one division of the micrometer eyepiece is 3 µm (6 x 10/20).

After determining the division value of the micrometer eyepiece, the stage micrometer is removed from the microscope stage, and the studied dust sample is placed in its place. The diameter of a dust particle is measured by determining how many divisions of the micrometer eyepiece scale it occupies.

Example. The diameter of the dust particle is equal to 3 divisions of the micrometer eyepiece. Therefore, the size of the dust particle is 3 x 3 = 9 µm.

During the Cell/15.html">Microscopy of the dust sample, the size of at least 100 dust particles is determined by constantly changing the field of view. The data are entered into a table (see the protocol template).

PROTOCOL TEMPLATE

Topic of the practical session.

1. Determination of dust concentration in the air.

Air sampling Location ... .

Air sampling method ... .

Sampling conditions (temperature ... , air flow rate ... , volume of the sample taken ... .

Reduction of air volume to normal conditions using the formula ... .

Method for determining dust concentration in the air ... .

Mass of the filter before air sampling ... mg.

Mass of the filter after air sampling ... mg.

Calculation of dust concentration in 1 m³ of air using the formula ... .

2. Determination of dispersity.

Table 3 Dust Analysis

Conclusion. Based on Sanitary and hygienic studies conducted in the industrial premises ..., it was established that the dust concentration ... is (does not exceed) the MPC. The dust is mainly represented by particles of ... size, which poses (does not pose) a hazard regarding fibrogenic effects.

Assignments FOR INDEPENDENT WORK

1. Test control of knowledge.

2. Solving situational tasks.

TESTS

1. The most common method for assessing air pollution by industrial dust, including pharmaceutical drugs, is:

A. Biological.

Б. Colorimetric.

B. Nephelometric.

Г. Gravimetric.

2. Industrial dust is classified by:

A. Origin.

Б. Method of formation.

B. Dispersity.

Г. Specifics of harmful action.

Д. All of the above factors.

3. According to its origin, dust is distinguished into:

A. Organic.

Б. Inorganic.

B. Mixed.

Г. Visible.

4. Depending on the method of formation, dust is differentiated into:

A. Condensation aerosol.

Б. Mixed dust.

B. Disintegration aerosol.

Г. Organic dust.

5. Depending on dispersity, dust is differentiated into:

A. Visible.

Б. Microscopic.

B. Ultramicroscopic.

Г. Inorganic.

6. The harmful effect of dust on the body depends on its properties. Which ones?

A. Particle shape.

Б. Dispersity.

B. Electrical charge.

Г. Chemical composition.

Д. All of the above factors.

7. Dust can exert the following effects on the body:

A. Toxic.

Б. Carcinogenic.

B. Fibrogenic.

Г. Sensitizing.

Д. All of the above.

8. The most common form of occupational lung pathology caused by dust exposure is:

A. Pneumoconiosis.

Б. Bronchial Asthma.

B. Pneumonia.

Г. Asthmoid bronchitis.

9. Which dust particles have the most pronounced fibrogenic effect and can cause pulmonary fibrosis?

A. Visible.

Б. Microscopic.

B. Ultramicroscopic.

10. Indicate the most effective measures aimed at eliminating the causes of dust generation:

A. Legislative measures.

Б. Therapeutic and prophylactic measures.

B. Technological measures.

Г. Planning and architectural measures.

SITUATION PROBLEMS

Using an electric aspirator, take an air sample in the production area of a pharmacy or pharmaceutical enterprise to determine the concentration of drug dust, assess the degree of air dust pollution by comparing the obtained result with the MPC, write a general conclusion, and provide recommendations for improving working conditions.

Problem 1.

An air sample was taken in the pharmacy dispensing room using an electric aspirator to determine the concentration of talc dust. The mass of the filter before sampling was 4.0003 g, and after sampling it was 4.0015 g. Sampling time was 10 min, sampling rate was 10 L/min, air temperature was 24 °C, and atmospheric pressure was 758 mm Hg. The MPC for talc dust is 4.0 mg/m³.

Problem 2.

An air sample was taken in the pharmacy dispensing room using an electric aspirator to determine the concentration of caffeine-sodium benzoate dust. The mass of the filter before sampling was 2.0016 g, and after sampling it was 2.0029 g. Sampling time was 25 min, sampling rate was 20 L/min, air temperature was 20 °C, and atmospheric pressure was 757 mm Hg. The MPC for caffeine-sodium benzoate dust is 0.5 mg/m³.

Problem 3.

An air sample was taken in the pharmacy dispensing room using an electric aspirator to determine the concentration of vegetable dust. The mass of the filter before sampling was 3.0033 g, and after sampling it was 3.0046 g. Sampling time was 28 min, sampling rate was 20 L/min, air temperature was 18 °C, and atmospheric pressure was 748 mm Hg. The MPC for vegetable dust is 10 mg/m³.

Problem 4.

An air sample was taken in the tablet manufacturing department of a pharmaceutical enterprise using an electric aspirator to determine the concentration of chlorpromazine dust. The mass of the filter before sampling was 2.0006 g, and after sampling it was 2.0012 g. Sampling time was 10 min, sampling rate was 20 L/min, air temperature was 24 °C, and atmospheric pressure was 754 mm Hg. The MPC for chlorpromazine dust is 0.3 mg/m³.

Problem 5.

An air sample was taken in the tablet manufacturing department of a pharmaceutical enterprise using an electric aspirator to determine the concentration of sulfadimethoxine dust. The mass of the filter before sampling was 1.0022 g, and after sampling it was 1.0026 g. Sampling time was 10 min, sampling rate was 15 L/min, air temperature was 22 °C, and atmospheric pressure was 755 mm Hg. The MPC for sulfadimethoxine dust is 0.1 mg/m³.

Problem 6.

An air sample was taken in the packaging department of a pharmaceutical enterprise using an electric aspirator to determine the concentration of theobromine dust. The mass of the filter before sampling was 1.0004 g, and after sampling it was 1.0024 g. Sampling time was 10 min, sampling rate was 20 L/min, air temperature was 19 °C, and atmospheric pressure was 748 mm Hg. The MPC for theobromine is 1.0 mg/m³.

Problem 7.

An air sample was taken in the tablet manufacturing department of a pharmaceutical enterprise using an electric aspirator to determine the concentration of tetracycline dust. The mass of the filter before sampling was 2.0028 g, and after sampling it was 2.0035 g. Sampling time was 25 min, sampling rate was 20 L/min, air temperature was 25 °C, and atmospheric pressure was 755 mm Hg. The MPC for tetracycline dust is 0.1 mg/m³.

Problem 8.

An air sample was taken in the packaging department of a pharmaceutical enterprise using an electric aspirator to determine the concentration of acetylsalicylic acid dust. The mass of the filter before sampling was 4.0006 g, and after sampling it was 4.0023 g. Sampling time was 10 min, sampling rate was 15 L/min, air temperature was 20 °C, and atmospheric pressure was 749 mm Hg.

The MPC for acetylsalicylic acid dust is 0.5 mg/m³.

Problem 9.

An air sample was taken in the packaging department of a pharmaceutical enterprise using an electric aspirator to determine the concentration of chloramphenicol dust. The mass of the filter before air sampling was 2.0001 g, and after sampling it was 2.0024 g. The sampling time was 15 min, the sampling rate was 10 L/min, the air temperature was 18 °C, and the atmospheric pressure was 752 mm Hg. The maximum allowable concentration (MAC) of chloramphenicol dust is 1.0 mg/m³.

Problem 10.

An air sample was taken in the pharmacy assistant room using an electric aspirator to determine the concentration of theobromine dust. The mass of the filter before air sampling was 4.0014 g, and after sampling it was 4.0019 g. The sampling time was 10 min, the sampling rate was 10 L/min, the air temperature was 18 °C, and the atmospheric pressure was 755 mm Hg. The maximum allowable concentration (MAC) of theobromine dust is 1 mg/m³.