Method for quantitative and qualitative evaluation of hazardous waste in laboratories of Isfahan University of Medical Sciences, Iran

Graphical abstract


Specifications table Subject area Environmental Health Engineering
More specific subject area Hazardous waste management, Methods name The applied method in this study is determination of quantitative and qualitative of hazardous waste in medical laboratories. The required information collected by using interview with laboratory staffs, completion of questionnaire, and refer to the available documents. The 33 laboratories (including 18 and 15 chemical and biological laboratories, respectively) and 1 clinic were selected for performance of this data research.

Sampling area
Isfahan University of Medical Sciences (IUMS) is a university specializing in basic medical sciences, clinical sciences, and health services that located in Isfahan, Iran. IUMS has located in same place by an area of 100 ha and has 10 faculties and 8720 students, approximately. Major activities on campus focused on teaching, research, and community services. Fig. 1 shows the location of IUMS.

Data collection
At first, in this data research, four out of ten faculties of IUMS that produce the highest amount of hazardous wastes (HWs) were selected for collection of required data. The required information collected by using interview with laboratory staffs, completion of questionnaire, and refer to the available documents. The 33 laboratories (including 18 and 15 chemical and biological laboratories, respectively) and 1 clinic were selected. To determine the total amount of HWs at IUMS, liquids, semisolid, and solid HWs were considered; finally, assuming that 1 L of HWs is almost equivalent to 1 kg, the total amount of HWs was expressed in mass unit.

Hazardous solid classification
In this data research, hazardous solid wastes classified according to United States of America (USA) Environmental Protection Agency that defined in below [5][6][7][8][9][10][11][12][13][14].The HWs that classified in several groups, we select one of character and has been shown in Table 1.
Ignitability: Ignitable wastes can create fires under certain conditions. Examples include liquids that readily catch fire, substances which are friction-sensitive or cause fire through absorption of moisture and ignitable compressed gases. Corrosively: Corrosive wastes include those that are strongly acidic or basic and those that are capable of corroding metal (such as containers, drums and barrels). Reactivity: Reactive wastes are unstable under normal conditions. They can create explosions, toxic fumes, gases, and vapors when mixed with water or heated in confinement. Toxicity: Toxic wastes are harmful or fatal when ingested or absorbed. The toxicity can be chronic or acute. Toxic wastes can cause carcinogenic, mutagenic and teratogenicity effects on human or other life forms.

Result
The characteristics of the investigated clinic and laboratories was showed in Table 2. Table 3 illustrates the generation rate of hazardous wastes (HWs) at the Isfahan University of Medical Sciences (IUMS). It shows that annually 2609.9 kg HWs generating in IUMS except for HWs that discharges to wastewater. The dentistry, public health, medical, and pharmacy faculties produced 104, 266.6, 793.9, and 1445.4 kg HWs per year, respectively that they are include 4%, 10%, 31%, and 55% in the total     amount of generated HWs at IUMS (Fig. 2). Fig. 3 shows the HWs production rate and population of the investigated faculties of IUMS. The dentistry, public health, medical, and pharmacy faculties produce 0.17, 0.5, 0.25, and 2.29 kg HWs/Capital. Year, respectively. Based on provided data in Fig. 4, in all faculties (except pharmacy), the highest share of HWs is related to the infectious type, while about pharmacy faculty, the amount of carcinogenic type is highest, although its difference was insignificant with infectious type. In term of HWs management, in all of the faculties, HWs including liquid or solid types, culture media, bloody waste, and needles is stored in containers temporarily. Usually, all HWs is collected weekly, but according to the type of HWs and its generation rate, sometimes daily and monthly. Some of the generated waste like culture media has the highest amount in faculties that autoclaved in situ and was collected with household wastes. But other HWs after autoclaving, is transferred to landfilling location by truck. Unfortunately, liquid HWs discharges into the municipal wastewater system and only the few laboratories is stored this waste type and have a specific plan.