[Table/Fig-7]:

Comparison of the results of our study with those of other studies in Iran [16-21].

Researcher	Reference number	Year	Sample type	Test	Milk contamination (%)	Compared with our study
Present	-	2009-2013	251 Samples of raw and pasteurized milk in Gonabad city	Copan	28.7% of schools, 21.4% of collection centers, 12.5% of factories	-
Mahmoudi	[16]	2012	200 samples of raw milk dairies in the outskirts of the Tabriz city	Delvo test	57.5%	Different method and results
Mahmoudi	[17]	2011	Samples of raw and pasteurized milk in Ilam Province	Copan	29.1% of milk in collection centers and 22.2% of pasteurized milk	Antibiotic residues of milk was higher in summer than that of the spring (similar to our study)
Manafi	[18]	2008	Raw and pasteurized milk East Azerbaijan Province	Delvo test	26% of industrial dairies, 16% of collection centers, and 30% of pasteurized milk	In our study, the percentage of contaminated milk samples was more than that of this study
Bahreinipur	[19]	2008	200 samples of raw and pasteurized milk collected in Mashhad city	Microbial inhibition test	30%	Different method and results
Ghanavi	[20]	2003	Milk samples collected in Iran	Different methods	27% of raw and 5% of pasteurized milk	Different method and results
Abedini	[21]	1973	800 samples of raw and pasteurized milk in Shiraz city	Disc method	2.7%	The samples were collected in 8 months (in our study during 12 months)