>Pur
   conc rate     state
1  0.02   76   treated
2  0.02   47   treated
3  0.06   97   treated
4  0.06  107   treated
5  0.11  123   treated
6  0.11  139   treated
7  0.22  159   treated
8  0.22  152   treated
9  0.56  191   treated
10 0.56  201   treated
11 1.10  207   treated
12 1.10  200   treated
13 0.02   67 untreated
14 0.02   51 untreated
15 0.06   84 untreated
16 0.06   86 untreated
17 0.11   98 untreated
18 0.11  115 untreated
19 0.22  131 untreated
20 0.22  124 untreated
21 0.56  144 untreated
22 0.56  158 untreated
23 1.10  160 untreated
> typeof(Pur$state)
[1] "integer"