Isolation of rapid growing mycobacteria from soil and water in Iran

A total of 350 soil samples were collected from different part of Uremia city and suburbs. We used 3%
sodium lauryl sulfate and 1% NaOH for decontamination of soil samples. Of 350 samples, mycobacteria
were isolated from 65 (18.3%) specimens. Mycobacterium fortuitum with 18(5.14) strains yielded the
highest frequency of isolation. The other isolates were: Mycobacterium peregrinum 11(3.14%),
Mycobacterium flvescens 10 (2.85%), Mycobacterium chelonae 6 (1.71%), Mycobacterium mucogenicum
6(1.71%), Mycobacterium thermoresistable 4(1.14%), Mycobacterium abscessus 3 (0.85%),
Mycobacterium neoaurum 2(0.57%), Mycobacterium smegmatis 2 (0.57%) and M. fortuitum third
biovalant complex 3 (0.85%). The mean pH of soil was 7.89 ± 0.379 (max 8.5, min 7.5). Our data showed
an abundant occurrence of mycobacteria in low pH (P value = 0001). We also collected 120 water
samples from rivers, brooks and drinking water. Water samples decontaminated were by adding cetyl
pyridinium chloride (CPC) to give final concentration of 0.05%. Mycobacteria isolated from 12 water
samples. The predominant isolated species were M. fortuitum and Mycobacterium cheloni. The majority
isolates were from brooks and surface waters.