Differences in genotoxicity between fine and ultra-fine air particulars in human peripheral blood lymphocytes

• Main Authors: Estonilo, Ma. Katrina Gale Z., Cazenas, Joedith Anne V., Villafuerte, Carlos Josef Q.
• Format: text
• Language: English
• Published: Animo Repository 2017
• Subjects: Atmospheric aerosols; Air > Pollution; Air quality management; Toxicology
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/5977
• Institution: De La Salle University

Particulate matter (PM) is a mixture of organic and inorganic compounds that can cause severe health problems. The present study aimed to investigate that PM size 1.0 µm and 2.5 µm have the ability to induce human genetic damage to blood lymphocytes using in-vitro micronucleus assay with the presence of binucleated cells and binucleated cells with micronucleus. PM samples were taken at the gate of Velasco building of De La Salle University using MetOne E-Sampler Instrument for PM1.0 and Thermo Scientific Instruments TEOM for PM2.5. The sampling periods were from December 2016 to March 2017 for PM2.5 and July 2015 to May 2016 for PM1.0 with gaps in between to change filters. A small amount of the samples were analyzed for their elemental composition using Atomic Absorption Spectroscopy (AAS). The PM was placed in a PB Max Karyotyping medium that was also used for the treatment to produce a stock solution of the PM. The stock solution was diluted to different PM treatment doses, namely 50 µg/mL, 100 µg/mL, 150 µg/mL. 0.5 ml of whole blood from a 21-year old female subject was exposed to 4.5 mL of each treatment solution. Two replicates were done for the assay. Visual microscopy was done to evaluate for the micronucleus frequency and CBPI. Test Guideline 487 (TG-487) were used as a guideline for the in-vitro micronucleus assay. All treatment conditions for both PM1.0 and PM2.5 revealed an increase in the frequency of micronucleus, however, only treatments from PM2.5 showed significant difference when treatments are compared with each other (p 0.01). The concentrates of PM1.0 only showed significant difference when each concentration is compared to the negative control (p 0.01). Using two-way ANOVA, it was shown that there is a significant difference between the genotoxicity of PM1.0 and PM2.5 (p 0.05), indicating that PM2.5 is highly genotoxic compared to PM1.0. Through the AAS, presence of Cd, Ca, Pb, K, Na, and Z were found in the studies however its numbers were considered inconclusive thus further elemental composition analysis is recommended for this study. Albeit inconclusive, the concentrations of the said metals are higher in PM2.5 compared to those in PM1.0 with Pb having the highest concentration in the samples as compared to the other hard metals that were analyzed. This may be the cause as to why PM2.5 is more genotoxic than PM1.0. It is concluded that in-vitro micronucleus assay is an effective biomarker for future health risk. In addition, it is also concluded that PM1.0 and PM2.5 are both genotoxic leading to increase health risk in humans. Lastly, the presence of metals in the PM samples contribute to the genotoxicity of PM.