Generation and composition of medical wastes from private medical microbiology laboratories

A study on the generation rate and the composition of solid medical wastes (MW) produced by private medical microbiology laboratories (PMML) was conducted in Greece. The novelty of the work is that no such information exists in the literature for this type of laboratories worldwide. Seven laboratories were selected with capacities that ranged from 8 to 88 examinees per day. The study lasted 6 months and daily recording of MW weights was done over 30 days during that period. The rates were correlated to the number of examinees, examinations and personnel. Results indicated that on average 35% of the total MW was hazardous (infectious) medical wastes (IFMW). The IFMW generation rates ranged from 11.5 to 32.5 g examinee−1 d−1 while an average value from all 7 labs was 19.6 ± 9.6 g examinee−1 d−1 or 2.27 ± 1.11 g examination−1 d−1. The average urban type medical waste generation rate was 44.2 ± 32.5 g examinee−1 d−1. Using basic regression modeling, it was shown that the number of examinees and examinations can be predictors of the IFMW generation, but not of the urban type MW generation. The number of examinations was a better predictor of the MW amounts than the number of examinees. Statistical comparison of the means of the 7 PMML was done with standard ANOVA techniques after checking the normality of the data and after doing the appropriate transformations. Based on the results of this work, it is approximated that 580 tonnes of infectious MW are generated annually by the PMML in Greece.