摘要：Organic volatiles and particulate emissions from the combustion of tire are believed to contain eco-toxic substances including polycyclic aromatic hydrocarbons (PAHs) and various reactive radical species which may initiate serious respiratory ailments such as asthma and lung tumors. This study investigates the nature and toxicological effects of particulate soot from tire burning. To simulate environmental pollution, 12-week-old male albino mice were exposed to tire particulate emissions at a rate of ~250 μgm﹣3·day﹣1 and their lung tissues were extracted for bioassay analyses. Comparisons were made between the lung tissues of mice exposed to the particulate emissions, and the control mouse in order to determine the health impact of particulates on the functioning of the lung soft tissue. The thermal degradation profile of tire was also investigated in the temperature range 200℃ - 500℃ and found that the highest mass loss was between 300℃ and 450℃. Organic volatiles were determined using a Gas Chromatograph coupled to a mass selective detector (MSD). Size distribution of soot particles was determined using Scanning electron microscope (SEM). Evidently, there was swelling and shrinking of lung tissue cells as a result of exposure to tire particulate emissions which caused disconnection of tissues and damage to the blood capillaries within the lung alveoli and microphages. Organic volatiles detected from tire combustion include benzene, anthracene, fluorene and pyrene. Soot particulate average sizes were found to be 16.23 ± 3.36 μm. Tire particulates caused grave damage to the lung tissues of the mice. These effects may be attributed to toxic organic volatiles as well as particulate emissions which may contain reactive active radicals and toxic organic intermediates and thus cause grave damage to the lung tissues of the mice.
