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The aim of this study was to obtain a longitudinal evaluation of the exposure to chlorpyrifos (CP) and chlorpyrifos-methyl (CPM) in agricultural workers in South Tyrol and in a residential group living in the same area. CP and CPM are widely used pesticides in agriculture. Biological monitoring of CP and CPM exposure in humans can be achieved by analyzing urinary levels of 3,5,6-trichloro-2-pyridinol (TCPy). TCPy a metabolite of CP and CPM which is produced by a two-step metabolic transformation. Between May 14th, 2014 and March 16th, 2015 we conducted a longitudinal study on 28 farmers actively working in spray pesticide treatment and 43 non-farmers living in the same agricultural area of South Tyrol (Italy). Urine samples were collected at two time points: during the pesticide treatment period and in a temporally distant season that should guarantee metabolite clearance. We developed and validated a liquid chromatography-tandem mass spectrometry (LC–MS/MS) method for the determination of urinary TCPy levels. During the treatment season, both farmers and residents showed higher TCPy levels (median = 6.8 and 6.73 ug/g creatinine, respectively) than during the non-treatment season (median = 2.54 and 3.22 ug/g creatinine, respectively), suggesting a similar effect of the pesticide spraying on both groups. However, the observed TCPy levels resulted in a daily CP and CPM intake well below the limits recommended by FAO/WHO. During the non-treatment season, non-farmers showed higher TCPy levels values than farmers, suggesting the existence of TCPy of other unmeasured sources of exposure not considered in this study. This suggests that, for a comprehensive evaluation of the risks associated with TCPy exposure, additional sources should be identified in addition to CP and CPM pesticides.

A thermal extraction cone penetrometry gas chromatography/mass spectrometry system (TECP GC/MS) has been developed to detect subsurface contaminants in situ. The TECP can collect soil-bound organics up to depths of 30 m. In contrast to traditional cone penetrometer sample collectors, the TECP extracts organics from soil without bringing the soil to the surface or into a collection chamber. Results show that polychlorinated biphenyls, polycyclic aromatic hydrocarbons (PAHs), chlorinated pesticides, and explosives can be recovered (60--95%) from wet or dry soil, with extraction efficiency compound-specific. The data are in remarkable agreement with closed cell thermal desorption (TD) experiments, where no organics are lost to the environment during heating. ECP GC/MS results also compare favorably with solvent-extracted GC/MS analyses and can be used to delineate the presence and extent of contamination at hazardous waste sites. Data illustrating TECP dependence on probe temperature and soil moisture as well as carrier gas liner velocity and volume (modified Reynolds number) are shown along with sample analysis data from two hazardous waste sites. The total ion and reconstructed ion current chromatograms are shown for PAHs collected by TECP from a coal tar contaminated soil obtained at a manufactured gas plant in Massachusetts. TECP and TD resultsmore » are within 15% for nonvolatile PAHs and within 50% of the solvent-extracted data.« less

The design of an in situ sampling device capable of thermally desorbing organics bound to subsurface soils at depths of up to 20 meters is described. The system consists of a heated transfer line and sampling probe that is hydraulically pushed to depth by a cone penetrometer. Results are presented illustrating the thermal extraction efficiency for polycyclic aromatic hydrocarbons (PAHs). Field tests were conducted under real-world conditions at a vehicle maintenance facility where 50 gal drums of petroleum by-products had been buried. PAH data were collected demonstrating the depth profiling features of the tool.

A new data analysis software system (Ion Fin- gerprint DetectionTM) has been developed to provide fast mass spectral data analysis. Methods have been devel- oped that can provide screening to quantitative gas chro- matography/mass spectrometry (GC/MS) data in 30 s to minutes. Compound selectivity is provided through a unique set of algorithms rather than GC separation. The data quality produced for volatile and semivolatile or- ganic contaminants under fast GC/MS conditions during dynamic site investigations carried out at Hanscom Air Force Base (Bedford, MA) and Joliet Army Ammunition Plant (Joliet, IL) are discussed. More than 800 samples were analyzed in each project, with state and federal reg- ulators accepting the data to complete remedial investi- gation/feasibility (RI/FS) studies. Q 1999 John Wiley & Sons, Inc. Field Analyt Chem Technol 3:55-66, 1999

This article describes new field-based technologies that support the Dynamic Workplan/Adaptive Sampling and Analysis Program employed to better characterize hazardous waste sites at lower cost. A laser-induced fluorescence (LIF) probe was designed and field-tested with a cone penetrometer (CP) for investigating petroleum contaminants present at under-ground tank farms. The LIF produced real-time quantitative data for naphthalene and semiquantitative results for total petroleum hydrocarbons and diesel range organics. Two different projects are described employing fast gas chromatography/mass spectrometry (GC/MS) in the field. A 70-foot heated transfer line and probe were used in combination with a cone penetrometer to thermally extract (TE) subsurface soil-bound semivolatile organics. In the second project, soil samples were collected by a GeoprobeTM and brought to the surface for analysis. The direct measurement TECP data produced semiquantitative results while the more conventional means of collecting and analyzing samples produced risk analysis quality data in the field. A new set of mass spectrometry algorithms provided the technology breakthrough for identifying and quantifying a wide range of Environmental-Protection-Agency-listed target compounds in the presence of high levels of matrix (petroleum) interferents under fast, 7 min/sample, GC conditions.

Research has focused on the development of a new set of mathematical algorithms, encoded in C(++), when combined with a thermal desorption sample introduction system provides quantitative analysis of a wide mixture of organic compounds in under 10 min by gas chromatography/mass spectrometry. The overall goal is to condense the time of analysis, including both the times required for sample preparation and for chromatographic separation. In this paper, results are presented where compound identification has been made for polychlorinated biphenyls, chlorinated pesticides, and polycyclic aromatic hydrocarbons present in the same solution and where gas chromatography separation times have been reduced from 40 to 5 min. For the latter, all compounds elute within 3.5 min, with structural isomers identified as the same compound. The 5-min analysis provides the foundation for rapid screening and on-line chemical measurements of multicomponent mixtures. Results are also presented where these same compounds are quantitatively analyzed in 10 min, with structural isomers identified individually, in the presence of a (25% v/v) weathered gasoline/engine oil mixture. Time-condensed complex mixture detection is now feasible making possible quantitative, high-throughput sample analyses.