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Composition, Production Rate and Management of Dental Solid Waste in 2017 in Birjand, Iran
Habibe Momeni1, Seyyedeh Fatemeh Tabatabaei Fard2, Aliye Arefinejad2
1Environmental Health Department, School of Public Health, Social Determinants of Health Research Center, Birjand University of Medical Sciences, Birjand, Iran.
Background:
The presence of toxic and pathogenic agents in the dental waste products has made it to be classified as "hazardous waste."
Objective:
To assess dental waste production rate and composition and approaches used to manage these waste products in 2017 in Birjand, Iran.
Methods:
48 dental clinics were evaluated in two months of 2017. Sampling was performed from each clinic 3 times a week. Samples were manually divided into 5 categories of chemical-pharmaceutical, infectious, semi-household, sharp and cutting materials, and toxic waste products, and weighed. A checklist containing 25 questions was used to evaluate the aspects of waste management in dental clinics.
Results:
The total amount of waste products generated in dental clinics was 7848.02 kg/ year in which semi-household waste had the highest quantity (4263.411 kg/year) and toxic waste had the lowest quantity (9.275 kg/year). Components with the highest amounts in dentistry waste products were nylon gloves (16.7%), paper and cardboard (13.4%), latex gloves (10.8%), and pharmaceuticals (10.2%). Waste separation was restricted to sharp and cutting waste. More than half (57%) of dental units were equipped with amalgam filter. Fixing solutions were directly discharged to sewage in 48.6% of clinics. There was no program to reduce waste generation in 54% of the clinics. Autoclave was the main tool for sterilizing dental instruments.
Conclusion:
This study showed a remarkable share of recyclable materials in the composition of dental waste and lack of special approach to manage waste in dental clinics. It is necessary to plan for minimizing generation of, separating, and recycling waste at source.
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