Passage VI
The pesticides propargyl bromide (PBr) and 1,3-dichloropropene (1,3-D) are removed from the soil by a variety of factors, including
uptake by plants, adsorption by soil, and breakdown by microorganisms, such as those found in manure. Also, PBr can degrade into propargyl
alcohol.
Three pairs of pesticide-free soil samples were collected for a study: heavily manure-amended (H1, H2), slightly manure-amended (S1, S2),
and unamended (U1, U2), as described in Table 1. On day 1, PBr was added to H1, S1, and U1 and 1,3-D was added to H2, S2, and U2 to
produce an initial pesticide concentration of 500 mg/L in each soil sample. PBr, propargyl alcohol, and 1,3-D concentrations in the soil were
measured at intervals over the next 12 weeks (see Figures 1– 3 ).