
%0 Journal Article
%A Ahmad, R. 
%A Kookana, R. S. 
%A Alston, A. M. 
%A Bromilow, R. H. 
%T Differences in sorption behaviour of carbaryl and phosalone in soils from Australia, Pakistan, and the United Kingdom
%J Soil Research
%D 2001/07/05
%V 39
%N 4
%P 893-908
%K Kd, Koc, particulate organic C, pesticides, SOC, sorption coefficient.
%R https://doi.org/10.1071/SR00021
%U https://www.publish.csiro.au/paper/SR00021 
%X Sorption of 2 nonionic pesticides, carbaryl (1-naphthyl methylcarbamate) and phosalone (S-6-chloro-2,3-dihydro-2-oxobenzoxazol-3-ylmethyl O,O-diethyl phosphorodithioate), was investigated for 48 soils from Australia, Pakistan, and the United Kingdom. A wide variation in sorption affinities of the soils to carbaryl and phosalone was observed. The sorption coefficient (K d) values for carbaryl ranged from 0.19 to 23.0 L/kg in Australian soils, from 0.99 to 59.7 L/kg in Pakistani soils, and from 1.09 to 23.0 L/kg in the UK soils. The K d values for phosalone ranged from 4.8 to 443 L/kg in Australian soils, from 15.5 to 1182 L/kg in Pakistani soils, and from 18.1 to 205 L/kg in the UK soils. To eliminate the effect of variation in organic carbon content among the soils, the K d values were normalised to the fraction of soil organic carbon (K oc ). However, K oc values for both pesticides varied by about an order of magnitude across the soils, decreasing in the following order: Pakistani &#62; Australian &#62; UK soils. Correlation between K d and organic carbon content of the soils was poor (r 2 = 0.44 and 0.46). The particulate organic C (53 &#181;m&#8211;2 mm) was only slightly better correlated with K d than the total organic C in the &#60;2 mm fraction of the soils. Thus soil organic C content alone is not a good predictor of sorption even for nonionic pesticides such as carbaryl and phosalone. Caution is needed during extrapolation of overseas data to predict sorption under local conditions. 
