Comparison of using polyurethane foam passive samplers and tree bark samples from Western China to determine atmospheric organochlorine pesticide

Polyurethane foam（PUF）passive samplers were deployed and tree bark samples were collected at 15 sites across western China in 2013,and the organochlorine pesticide（OCP）concentrations in the samples were determined.Dichlorodiphenyltrichloroethane and its degradation products（collectively called DDTs）,hexachlorocyclohexanes（HCHs）,and hexachlorobenzene（HCB）were the dominant OCPs in the PUF samples and tree bark samples.The mean DDTs,HCHs and HCB concentrations were 33,22 and 18 ng/sample in the PUF samples,and 428,74,and 43 ng/（g lipid weight（lw））in the tree bark,respectively.The OCP concentrations in the air,calculated using PUF–air and tree-bark–air partitioning models,were of the same order of magnitude.Both sample types showed that relatively fresh inputs of DDT and HCHs to the environment have occurred in western China.Meanwhile,PUF passive samplers were compared with the use of tree bark samples as passive samplers.The OCP compositions in the PUF and tree bark samples were different.Only the relatively stable OCPs（such as HCB,β-HCH and p,p′-dichlorodiphenyldichloro-ethylene（DDE））were consistent in the PUF and tree bark samples.