Detector for particulate polycyclic aromatic hydrocarbons in water

Abstract

It is estimated that most polycyclic aromatic hydrocarbons (PAHs) in environmental water are not dissolved but rather in particulate form. Nevertheless, the currently available optical detectors are not suited for proper sampling of solid PAHs. A new setup for direct sampling and quantification of suspended particulate PAHs in water is suggested. It is based on a polymeric film that has the capability of dissolving PAH particulates, coupled to a traditional laser-induced fluorescence probe. Kinetics and performance of two sampling modes have been studied: bulk sampling, by immersing the probe into the water, and surface sampling, by laying the film on the water surface. The latter method has proved to be more sensitive; however, it is diffusion-limited. Linear calibration plots have provided quantification over a wide concentration range with detection limits in the ppb range (these could be improved by using a modified probe). The effects due to other particulates in water have been studied and only little interferences have been observed. The possibility of analysis of PAH mixtures has been addressed and it has been concluded that multivariate analysis is needed.

Expansion dynamics of ultrafast laser produced plasmas in the presence of ambient argon

“…This could be attributed to differences in physical properties of Zn as compared to Cu and similar observations were made previously with ns LA. 42,43 The species expansion trends were the same for both Zn and Cu at various pressures. Since Zn always moves faster than Cu and is present in the plume front, Zn data was used as representative data for brass plume expansion for fitting drag or blast models.…”

Determination of polycyclic aromatic hydrocarbons by four-way parallel factor analysis in presence of humic acid

“…It is confirmed that the long-term exposure to these chemicals will induce health problems including cancer, transgenation and deformity. So far, sixteen kinds of PAHs have been identified as priority pollutants by the US EPA [1,2]. Meanwhile, a lot of analytical techniques have been developed to recognize and monitor these PAHs effectively.…”

Investigating the temporal trends in PAH, PCB and OCP concentrations in Hartbeespoort Dam, South Africa, using semipermeable membrane devices (SPMDs)

“…Due to their ubiquitous nature, hydrophobic organic compounds such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) have been identified as environmental contaminants in almost every compartment of the global system (ATSDR, 2009). As byproducts of incomplete combustion of organic compounds, pyrosynthesis or pyrolysis of hydrocarbons, PAHs are released to the environment by both natural and anthropogenic sources (Levinson et al, 2008). PAHs may also reach water systems through oil spills and direct industrial effluent discharges.…”