SEDIMENTABLE ATMOSPHERIC DUST IN ADMINISTRATIVE OFFICES IN THE DISTRICTS OF THE PROVINCE OF LEONCIO PRADO

Objective: Evaluate the level of atmospheric settleable dust concentration in three administrative offices of six district municipalities in the province of Leoncio Prado, Huánuco; from May to October 2022. Method: The methodology of passive sampling with receptor plates was employed, and the atmospheric settleable dust sampling equipment was placed in the administrative offices of civil registry, reception, and human resources. Results: The civil registry administrative office of the Castillo Grande District Municipality recorded an average concentration of 1.121 mg/cm²/30 days. In the Pueblo Nuevo District Municipality, the civil registry office recorded 0.530 mg/cm²/30 days and the reception office recorded 0.539 mg/cm²/30 days. All of these exceed the maximum permissible limit established by the World Health Organization (WHO) (0.5 mg/cm²/30 days). Contribution: This study will contribute to improving air quality and safeguarding the health of workers in these administrative offices affected by pollution, thereby ensuring a healthier work environment.


INTRODUCTION
In recent years, population growth has led to a series of adverse effects on air quality, raising global concern.In Peru, the population reached 33 million 726 thousand inhabitants (INEI, 2023), which has had a considerable impact on air pollution.Specifically, human actions and emissions from anthropogenic activities are significant factors in air pollution.
The concentration of atmospheric settleable dust is generated during processes such as crushing, pulverizing, drilling, and transportation, which produce large fragments and release dust particles into the atmosphere (Reategui-Inga et al., 2024a).In this context, the settling dust presents a variety of particle morphologies and mineralogical compositions that vary according to their origin (Reategui-Inga et al., 2024b).This results in a complex composition influenced by the deposition of atmospheric aerosols from both natural and anthropogenic sources (Gómez et al., 2004).Additionally, atmospheric settleable dust poses a threat to human health, as its size allows it to enter the body through the respiratory system, causing damage to various organs (Zhang et al., 2009).
Organizations such as the Dirección General de Salud Ambiental (DIGESA) and the Servicio Nacional de Meteorología e Hidrología del Perú (SENAMHI) utilize WHO standards for monitoring studies (Marcos et al., 2008).According to WHO, the permissible concentration is 0.5 mg/cm 2 /30 days.The severity of risk is inversely related to particle size, which can penetrate deep into the lungs (Oyarzún, 2010).During summer, atmospheric dust levels increase due to higher dispersion caused by wind speed (Mahato & Singh, 2020).Furthermore, vehicular traffic and unpaved streets contribute to dust suspension, leading to higher levels of settleable atmospheric dust concentration (Dubey et al., 2024;Thatcher, 1995).
In this same context, there is a need to measure the amount of dust deposited in municipal administrative offices.For this purpose, the use of receptor plates method (BOE, 1976) was chosen due to its practicality and low cost, which facilitates the assessment of this concentration.This highlights the research objective to evaluate the level of settleable atmospheric dust  Macedo & Pérez (2023), conducted a study to determine the levels of settleable atmospheric dust on three avenues in Iquitos in 2022.The receptor plate method was employed, with twelve stations set up for PAS evaluation.
Carrasco & Rojas (2022), conducted research to determine the concentration of settleable atmospheric dust and its impact on the health of residents along Augusto B. Leguía Avenue in Chiclayo city.They employed the receptor plate method at ten evaluation points, identifying the highest concentration exceeding the maximum permissible limit at point six, with a value of 2.1692 mg/cm 2 /month.Additionally, surveys conducted among avenue residents revealed that 70% of them believe that road deterioration influences the presence of settleable atmospheric dust, and all residents reported that their health is affected by this pollutant.

METHODOLOGY
The procedure established in the regulation issued on August 10, 1976, which sets out technical guidelines for the analysis and evaluation of chemically based pollutants present in the atmosphere (BOE, 1976), was applied.The collection equipment was adapted according to the model by Marcos et al. (2008).Subsequently, installation was carried out, during which it remained stationary throughout the measurement period, with data collection occurring every 30 days.Afterward, the concentrations of settleable atmospheric dust retained in the samples from each month were analyzed for the three administrative offices.
The process involved evaporating a portion of the filtered liquid to obtain the quantity of soluble settleable material.This was conducted in a calibrated oven at a temperature of 105°C, where a crucible containing 50 ml of the filtered liquid was placed.Subsequently, the dry residue obtained was weighed, and this value was compared with the total volume of the liquid.The difference Using the weight, the area of the clock face, the volume of collected water (500 ml), and the collection period, the amount of soluble settleable material was calculated in mg/cm 2 /days.In this regard, the insoluble material, also known as total insoluble residue, was determined by comparing the weight of the filter before and after the filtration process.For this procedure, the receptor clock face plates were first washed in 500 ml of deionized water.
Then, the contents passed through a glass microfiber filter using a buncher funnel, thus obtaining the dust.Carefully removing the filter, it was placed in a Petri dish and then transferred to an oven at 105°C for 12 hours to achieve a constant weight.
Finally, after cooling in a desiccator, the filter was weighed using an analytical balance to record the data.Considering the area of the clock face and the exposure period, the amount of insoluble settleable material was also determined and expressed in mg/cm 2 /days.

SEDIMENTABLE ATMOSPHERIC DUST CONCENTRATION
To achieve this concentration, the sum of the insoluble and soluble settleable material was calculated using the following formula (Silva, 2021): where: C= Sedimentable atmospheric dust concentration WPAS= Weight of the dus (mg) EA= Exposed area (cm 2 ) ED= Exposure days A comparison was made of the settleable atmospheric dust concentrations in the three municipal administrative offices relative to the limit established by the World Health Organization, which is 0.5 mg/cm 2 /30 days.

OFFICES
In Figure 2, it is observed that the civil registry office in the District Municipality of Castillo Grande has 1.121 mg/cm 2 /30 days, followed by the District Municipality of Pueblo Nuevo with 0.539 mg/cm 2 /30 days.Additionally, the main office in the District Municipality of Pueblo Nuevo recorded 0.531 mg/cm 2 /30 days.All concentrations exceeded the WHO's MCL of 0.5 mg/cm 2 /30 days.(Pacsi, 2016), if this traffic is constant, the significant influence of motor vehicles on the accumulation of settleable particles is highlighted.Mazher et al. (2008) indicates that vehicular activity contributes to dust dispersion.
Furthermore, the lack of pavement on surrounding roads and the absence of green areas nearby contribute to indoor pollution.
Atmospheric Dust in Administrative Offices In the Districts of the Province of Leoncio Prado, Peru: A Diagnosis for the Fulfillment of the Objective of Sustainable Development-Health and Well-Being concentration in administrative offices of six district municipalities in the province of Leoncio Prado to determine if they exceed the maximum permissible limits set by the WHO.

Livia
et al. (2021), aimed to determine air pollution caused by settleable particulate matter in households within the urban area of Leoncio Prado province.Twelve sampling stations were installed, revealing that seven of these stations exceeded the maximum permissible limit.Areas with elevated concentrations included Electrocentro with 0.633 mg/cm 2 /month, Luyando with 0.955 mg/cm 2 /month, Brisas del Huallaga with 0.966 mg/cm 2 /month, Carbajal, G., S., Reategui-Inga, M., Durand, R., P., Coaguila-Rodriguez, P., Aguirre-Escalante, C., Alvarado, V., B. (2024) Sedimentable Atmospheric Dust in Administrative Offices In the Districts of the Province of Leoncio Prado, Peru: A Diagnosis for the Fulfillment of the Objective of Sustainable Development-Health and Well-BeingCastillo Grande entrance with 0.989 mg/cm 2 /month, and Supte San Jorge with 1.018 mg/cm 2 /month.Cevallos, (2018), conducted a study aimed at determining the level of particulate matter sedimentation pollution in the air of Ambato, Ecuador.Six strategic points were selected for assessment within the urban area.The collection method used Petri dishes for PM sedimentation and the Dust Trak TM II equipment for PM analysis.Results identified higher concentrations of settleable dust at the Redondel de Huachi Chico and the Mercado Modelo, primarily attributed to heavy vehicular traffic in this area, including both light and heavy-duty vehicles.These locations encompass residential, commercial, and institutional areas.In the other four sectors of the urban region, concentrations were lower.Passive sampling was conducted over 30 days (1 month) for the six samples, revealing that in the Redondel de Huachi Chico sector, the sedimentable dust concentration (0.57 mg/cm 2 /month) exceeded WHO standards.
Atmospheric Dust in Administrative Offices In the Districts of the Province of Leoncio Prado, Peru: A Diagnosis for the Fulfillment of the Objective of Sustainable Development-Health and Well-Being in weight of the crucible represented the quantity of soluble settleable material.
Figure 1.Collector equipment Figure 2.Average Concentration of Settleable Atmospheric Dust in Administrative

4. 2
SETTLEABLE ATMOSPHERIC DUST CONCENTRATION IN THE DISTRICTMUNICIPALITIESIn Figure3, the highest concentration of settleable atmospheric dust is observed in the District Municipality of Castillo Grande with 0.494 mg/cm²/30 days, and the lowest in the District Municipality of Mariano Damaso Beraun with 0.075 mg/cm²/30 days.None of the district municipalities exceed the WHO's maximum permissible limit of 0.5 mg/cm²/30 days.

Figure 3 .
Figure 3. Average concentration of settleable atmospheric dust in the district municipalities