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The effects of methyl methacrylate on nasal cavity, lung, and antioxidant system (an experimental inhalation study)
Ozlem Aydin1, Gulen Attila, Arife Dogan
1Department of Pathology, Mersin University Medical School, Mersin-Icel, Turkey. ozlemaydin66@hotmail.com
Abstract:
Methyl methacrylate (MMA) is a monomer, commonly used in neurosurgery, orthopedic surgery, and in dental clinics. The adverse effects of this monomer are well described in the literature. This study was designed to evaluate the effects of MMA on nasal cavity, lung, and antioxidant status. For this purpose, two experimental groups of rats were exposed to MMA (at 1,000 ppm, 6 h/day, 5 days/week for 4 weeks) by inhalation under poor (group A, n = 12) and normal ventilation (group B, n = 11) conditions. A control group (group C, n = 10) received normal air. Degeneration of olfactory epithelium, bronchopneumonia, interstitial pneumonia, hemorrhage, atelectasis, edema, emphysema, and bronchial epithelial hyperplasia were observed in groups A and B. Emphysema was the most common lesion. Bronchopneumonia with abscesses was only observed in group A. Glutathione levels were significantly decreased and malondialdehyde levels were significantly increased in group A. No significant difference was observed in superoxide dismutase levels between the groups. The data presented indicate that before using MMA, adequate protection systems should be in place to prevent occupationally related MMA respiratory-tract injuries.
Insights
Exposure to methyl methacrylate (MMA) caused significant respiratory damage in rats, particularly under poor ventilation. Implementing adequate protection is crucial to prevent occupational MMA-related injuries.
Area of Science:
- Toxicology
- Occupational Health
Background:
- Methyl methacrylate (MMA) is widely used in medical procedures, including neurosurgery, orthopedics, and dentistry.
- Adverse effects of MMA are documented, necessitating further investigation into its impact on respiratory health.
Purpose of the Study:
- To evaluate the toxicological effects of methyl methacrylate (MMA) inhalation on the nasal cavity, lungs, and antioxidant status in rats.
- To compare the impact of MMA exposure under poor versus normal ventilation conditions.
Main Methods:
- Rats were exposed to MMA (1,000 ppm, 6 h/day, 5 days/week for 4 weeks) via inhalation.
- Two experimental groups experienced MMA exposure under poor (Group A) and normal (Group B) ventilation.
- A control group (Group C) was exposed to normal air.
Main Results:
- Both MMA-exposed groups (A and B) exhibited nasal and lung pathologies, including olfactory epithelium degeneration, bronchopneumonia, interstitial pneumonia, hemorrhage, atelectasis, edema, and emphysema.
- Emphysema was the most prevalent lesion observed.
- Bronchopneumonia with abscesses was exclusively found in the poor ventilation group (Group A).
- Group A showed significantly decreased glutathione and increased malondialdehyde levels, indicating oxidative stress.
Conclusions:
- Methyl methacrylate (MMA) inhalation causes significant respiratory tract injuries.
- Poor ventilation exacerbates MMA toxicity, leading to more severe lung damage and oxidative stress.
- Adequate protective measures are essential to prevent occupationally related respiratory injuries from MMA exposure.
